Abstract

Consumers are becoming more aware of the effect of the food they eat on their health. One of the ways they hope to reduce their risk of cardiovascular disease is by consuming more foods enriched with n-3 polyunsaturated fatty acids (PUFA). Due to the high content of α-linolenic acid (LNA), dietary flaxseed is a good source for increasing n-3 PUFA in poultry meat. A study was conducted with 2 primary objectives: to establish the distribution of n-3 PUFA between tria-cylglycerol (TAG) and phospholipid of broiler chicken breast and thigh meat and to determine the duration of dietary flaxseed supplementation required to ensure a level of n-3 PUFA of 300 mg per 100 g of meat necessary to label meat as a source of n-3 PUFA. This experiment was conducted as a 2 × 8 factorial, with 2 dietary levels of ground flaxseed (10 and 17%) and 8 durations of dietary flaxseed before processing [0 (control), 4, 8, 12, 16, 20, 24, and 35 d]. A total of 128 Ross × Ross 308 mixed-sex broilers were evaluated to 35 d of age. Breast and thigh meat fatty acid composition was analyzed on duplicate samples of ground meat pooled from 8 birds per treatment. Broken-stick analysis was used to estimate the duration required to achieve 300 mg of n-3 PUFA per 100 g of breast meat. Results clearly indicated that LNA was mainly deposited in the TAG fraction of both breast and thigh meat. Enriching the chicken breast meat with 300 mg of n-3 PUFA per 100 g of meat was achieved in 11.3 and 26.2 d with a 17 and 10% level of flaxseed in diet, respectively. Although a significant increase of n-3 long-chain PUFA (20:5n-3, 22:5n-3, and 22:6n-3) was found in the phospholipid and TAG fraction of both tissues, the concentration of these functional components was low. More than 95% of n-3 PUFA enrichment was due to LNA.

INTRODUCTION

Cardiovascular disease (CVD) is one of the leading causes of death in men and women of all ethnic groups. Consuming saturated dietary fats and n-6 polyunsaturated fatty acids (PUFA) increases the risk of CVD, whereas consumption of n-3 PUFA may reduce CVD incidence (Simopoulos, 1997). Humans historically consumed a diet with an n-6:n-3 ratio of 1:1 to 4:1 (Eaton et al., 1996; Simopoulos, 2006). However, the typical ratio in developed countries is now greater than 10:1 (Azain, 2004). Major sources of n-6 PUFA are vegetable oils such as corn, safflower, and soybean oil, whereas n-3 PUFA sources include fish such as salmon, trout, and tuna and plant sources such as flaxseed (Schmitz and Ecker, 2008).

Among the PUFA, fatty acids essential for humans are α-linolenic acid (18:3n-3; LNA), and linoleic acid (18:2n-6; LA; Bezard et al., 1994; Schmitz and Ecker, 2008). Because humans cannot synthesize LNA and LA, they must be included in the diet. In mammalian cells, LA and LNA are further metabolized to long-chain PUFA (LC-PUFA). The n-6 fatty acid LA is converted to γ-LNA (C18:3n-6), and diomo-γ-LNA (20:3n-6) to form the key intermediate arachidonic acid (C20:4n-6; AA) by various desaturase and elongase enzymes. Arachidonic acid is further metabolized to do-cosapentaenoic acid (C22:5n-6) or eicosanoids (Schmitz and Ecker, 2008). The n-3 fatty acid LNA is converted to stearidonic acid (18:4n-3) and eicosatetraenoic acid (20:4n-3) to form eicosapentaenoic acid (20:5n-3; EPA) using the same series of enzymes as those used to synthesize AA. Eicosapentaenoic acid is further metabolized to docosahexaenoic acid (22:6n-3; DHA) or eicosanoids (Bezard et al., 1994; Schmitz and Ecker, 2008). Eicosanoid production from LA has been associated with CVD, inflammatory disorder, and cancer (Emken et al., 1994; Siddiqui et al., 2005). To substantially depress the production of eicosanoids from AA requires a dietary intake of LNA of approximately 1% of the total energy requirement. This is because LNA competes very effectively with LA for common fatty acid desaturases and elongates that convert C18 PUFA to their C20 and C22 homologs (Emken et al., 1994).

The US Food and Drug Administration (2004) gave qualified health claim status to n-3 PUFA. It was stated that “supportive but not conclusive research shows that consumption of EPA and DHA may reduce the risk of coronary heart disease.” Omega-3 PUFA-enriched poultry meat has the potential to help meat consumers increase their n-3 PUFA intake. A minimum level of 300 mg of n-3 PUFA per 100 g of meat is needed to label the product n-3 PUFA-enriched (CFIA, 2003).

The LNA in the broiler diet is transferred to muscle (Rymer and Givens, 2005). Flaxseed oil contains 50 to 60% LNA, which is the precursor of the n-3 LC-PUFA family. For these reasons, it is used widely in n-3 PUFA muscle enrichment (Gonzalez-Esquerra and Leeson, 2000; Lopez-Ferrer et al., 2001a; Cortinas et al., 2004; Dublecz et al., 2004; Villaverde et al., 2006).

Dietary fatty acids are distributed between neutral lipid and phospholipid (PL) in animal muscle (Gandemer, 2002). Phospholipid is an essential component of cell membranes and its amount remains fairly constant, or increases a little, as the animal increases in fatness (Wood et al., 2008). Neutral lipids (triacylglycerol, TAG), mainly rich in saturated and monounsaturated fatty acids, are found in the i.m. adipocytes (adipose tissue) located in the perimysium (Sanosaka et al., 2008). Adipocyte number and size increases with the total lipid content of the muscle (Mourot and Hermier, 2001; Wood et al., 2008). Breast meat contains more lipid as PL, whereas in thigh meat, the predominant lipids are TAG (Gonzalez-Esquerra and Leeson, 2001). Enrichment of breast meat with n-3 PUFA may therefore be more difficult to achieve because the potential depot is smaller.

To increase n-3 PUFA concentration in the tissues, we used different levels of flaxseed fed for different durations of time before processing. The present study characterizes the fatty acid composition of breast and thigh meat and its distribution in the TAG and PL fractions. Additionally, the feeding period necessary to achieve 300 mg of LNA/100 g of meat was tested. This study builds on the results of a previous trial (Zuidhof et al., 2009) to further understand the dynamic of n-3 PUFA enrichment in breast meat tissues.

MATERIALS AND METHODS

Study Design

An Institutional Animal Policy and Welfare Committee approved all experimental protocols. High and low levels of ground whole flaxseed (Omegaflax, Archer Daniels Midland, Alberta, Canada; 10 and 17%, respectively) were fed for 8 lengths of time before processing at 35 d of age. A control diet containing no flaxseed was provided up to the time that birds were moved to the flaxseed diets. Three nutritional phases (starter, grower, and finisher) were implemented (Table 1). To avoid performance issues from feeding high flax diets from a young age, only 2 diets (control and 10%) were provided to low and high enrichment × 35 d birds during the 0 to 11-d starter phase. From 11 d, birds in the high enrichment treatment received 17% ground flax-seed. Thus, birds received diets enriched with flaxseed meal for 0 (control), 4, 8, 12, 16, 20, 24, or 35 d before processing.

Stocks, Management, and Sampling

One hundred twenty-eight Ross × Ross 308 mixed-sex broilers were evaluated in this study. At day of hatch, 22 chicks were placed randomly into 6 pens. Two pens of each diet were used. Beginning in the grower phase (11 d of age), birds were moved from the control diet to either a 10 or 17% flaxseed diet at 4-d intervals. Once moved, birds received the enriched diet until processing at 35 d. The birds were provided ad libitum access to experimental diets and to water. A lighting program of 23L:1D was used for the entire 35-d growing period.

On d 35, eight birds per treatment were processed after a 12-h feed withdrawal period. The birds were electrically stunned and then bled for 2 min. After scalding (63°C) for 45 s, carcasses were mechanically defeathered, manually eviscerated, and cut up after reaching an internal carcass temperature of 4°C. Uptake of fatty acids into the broiler meat was determined. Thigh and breast tissues were analyzed skinless. Eight carcasses per each dietary treatment were used for the analysis. Meat samples from each dietary treatment were pooled and passed through a meat grinder twice. For both thigh and breast tissue, 2 replicates per treatment were analyzed.

Fatty Acid Analysis

Extraction of Muscle Lipids and Separation of Lipid Classes.

The tissue samples (2 g) were pulverized at dry ice temperature (−78.5°C) according to the procedure described by Kramer and Hulan (1978). The total lipids were extracted using the method of Folch et al. (1957). Total lipid samples were separated into PL and TAG fractions by using the thin layer chromatography procedure described by Christie and Breckenridge (1989), with hexane:ether:formic acid 80:20:2 vol/vol used as a developing agent (Fisher Scientific Ltd., Nepean, Ontario, Canada). Silica Gel G plates of 20 × 20 cm (250 μm) were used as the thin layer chromatography plates (Analtech Inc., Newark, DE).

Derivatization and Gas Chromatography Analysis.

Total fatty acid profile and composition of the PL and TAG lipid classes for breast and thigh meat were analyzed by gas chromatography (GC) on replicate samples. The transmethylation method was conducted according to Christie and Breckenridge (1989). Extracted fat was diluted with chloroform; 2 mL of methanolic HCl (HCl in methanol; Supelco, Bellefonte, PA) was added to 50 μL of the mixture (extracted fat and chloroform). To stimulate the reaction, samples were put into a 50°C water bath for 60 min. The fatty acid composition was determined with a GC Varian 3400 gas chromatograph (Varian, Walnut Creek, CA) equipped with a flame ionization detector and a Supelco SP-2560 capillary column (100 m × 0.25 mm × 0.2 μm film thickness). Operating conditions for the GC were as follows: initial temperature of 45°C was held for 4 min; increased 13°C/min to 175°C, which was maintained for 27 min. At a rate of 4°C/min, a temperature of 215°C was reached, which was maintained for 29 min. A cool-on-column injection method was used, with an initial and final injector temperature of 50°C (0.2 min) and 230°C (78 min), respectively, increasing at a rate of 150°C/min. The temperature of the detector remained at 230°C and the column head pressure of the carrier gas (helium) was 2.7 atm. The fatty acid peak integration was performed using the Galaxie Chromatography Data System (Varian). Fatty acids were quantified using heptadecanoic acid (17:0) as an internal standard (Varian) and were identified by comparison of authentic standards (GLC-463, Nu-Chek Prep Inc., Elysian, MN). Total n-3 fatty acid levels were calculated as LNA + EPA + 22:5n-3 + DHA. Total n-6 fatty acid levels were calculated as LA + 18:3 + 20:2 + 20:3 + AA + 22:4. Saturated fatty acid levels were calculated as 14:0 + 16:0 + 18:0 + 20:0. Monounsaturated fatty acid levels were calculated as 16:1n-7 + 18:1n-7 + 18:1n-9 + 22:1n-9. Polyunsaturated fatty acid levels were calculated as LA + LNA + 18:3n-6 + 20:2n-6 + 20:3n-6 + AA + EPA + 22:4n-6 + 22:5n-3 + 22:6n-3.

Statistical Analysis

The data were analyzed as a 2 × 8 factorial ANOVA, with 2 dietary levels of ground flaxseed (low, 10% and high, 17%) and 8 feeding period durations before processing: 0 (control), 4, 8, 12, 16, 20, 24, and 35 d. The MIXED procedure of SAS (SAS 9.1, SAS Institute Inc., Cary, NC) was used. Pooled estimates of variance were used. Differences between least squares means were determined using Tukey’s honestly significant difference test and were reported as significant at the P < 0.05 level.

To estimate the duration of the dietary flaxseed required to reach the maximum concentration of n-3 enrichment of meat, the simplest piecewise regression or broken-stick analysis was conducted (Toms and Lesperance, 2003) for each dietary flaxseed level using the NLIN procedure of SAS (SAS 9.1, SAS Institute Inc.). In this model, breakpoints are used to estimate the thresholds at which the response variables change differently in relation to independent variables. The model was established as follows:

graphic

where Y is the n-3 PUFA concentration in breast meat (mg/100 g); x is the duration for which dietary flax-seed was provided (d); C is the plateau, or maximum level of n-3 PUFA enrichment achieved within a dietary flaxseed level [mg/100 g, where C = β 0 + β 1(χ)];χ is the breakpoint, or the threshold duration (d) of dietary flaxseed at which the plateau was reached [χ = (C − β 0)/β 1]; β 0 is the intercept (n-3 level in breast meat on the control diet; mg/100 g); and β 1 is a linear coefficient describing the rate of increase of n-3 PUFA in breast meat (mg/100 g per day).

Regression analysis was conducted using the NLIN procedure of SAS (SAS 9.1, SAS Institute Inc.) to estimate changes in Δ5-desaturase activity (20:4n-6/20:3n-6) and elongase + desaturase activity (20:4n-6/18:2n-6) with duration of feeding flaxseed. The models were established as follow:

 

\[\mathit{Y}\ =\ {\beta}_{0}\ +\ {\beta}_{1}\mathit{x}\]

 

\[\mathit{Y}\ =\ {\beta}_{0}\ +\ {\beta}_{1}\mathit{x}\ +\ {\beta}_{2}\mathit{x}^{2},\]

where Y is the enzymatic activity, x is the duration of feeding flaxseed, β 0 is the intercept (desaturase and elongase activity on the control diet), and β 1 and β 2 are the regression coefficients.

RESULTS AND DISCUSSION

Fatty Acid Content of the Diets

Control diet LNA levels ranged from approximately 5 to 7 mg/g of diet (Table 2). Adding 10% flaxseed to the starter diet resulted in a 4.4-fold increase in dietary LNA, from 5.3 to 23.5 mg/g of diet. Adding 10% flaxseed meal to the grower and finisher diets resulted in approximately a 3-fold increase in LNA. Addition of 17% flaxseed meal in the grower and finisher diets resulted in a 4- and 5-fold increase in dietary LNA, respectively.

Fatty Acid Composition of the Lipid Classes in Broiler Meat

Results for PL and TAG fatty acid composition of both breast and thigh meat for main effects and treatment interactions (level of flaxseed and duration) are presented in Table 3. Means and SE of both breast and thigh meat PL and TAG fatty acids are reported inTables 4567 and 8. Results for total lipid tissue n-3 fatty acids are reported in Table 9.

PL Fraction.

Thirteen and 15 fatty acids were identified in breast and thigh meat PL, respectively (Tables 4 and5). Linoleic acid, oleic acid (18:1), and palmitic acid (16:0) were the most predominant fatty acids in PL, each occurring at a level of 22% in breast meat and 25, 19, and 18%, respectively, in thigh meat. Muscle type influenced the fatty acid profile of PL membranes; the long-chain n-6 PUFA 20:3 and 22:4 were identified only in thigh meat PL. On average, n-6 PUFA and n-3 PUFA were higher in thigh PL than breast PL (113.8 vs. 86.90 mg/100 g of meat and 31.6 vs. 25.8 mg/100 g of meat, respectively). These results might be related to the different muscle fiber composition of leg muscle (musculus biceps femoris) compared with breast muscle (pectoralis major). Kriketos et al. (1995) reported a higher concentration of n-6 and n-3 PUFA in type I (slow-twitch oxidative) and type IIa fibers (fast-twitch oxidative-glycolytic) than type IIb fibers (fast-twitch glycolytic). The higher PUFA content of thigh PL could be explained as a result of a higher proportion of type I and type IIa fibers in musculus biceps femoris (Papinaho et al., 1996) compared with pectoralis major.

In both dietary treatments, the different periods of flaxseed supplementation did not change LNA content in the breast tissue (Table 4) and thigh tissue (Table 5) in relation to control groups. By d 35, the amount of LNA in the PL fraction of the breast was 3.074 and 3.211 mg/100 g of meat for the low and high supplementation, respectively. The amount of PL LNA in the thigh was higher compared with the breast by d 35. Linolenic acid enrichment did not occur in the PL membranes. Our results are in agreement with Gonzalez-Esquerra and Leeson (2001), who reported that LNA is not stored in PL membranes of chicken breast muscle. Similar results were obtained by Warnants et al. (1999) in extracted fat from pig longissimus muscle. In contrast, a study conducted in pigs fed 15% ground flaxseed demonstrated an 11.7-fold increase in PL LNA content after 42 d (Specht-Overholt et al., 1997).

Muscles contain significant amounts of LC-PUFA, which are mainly formed in the liver from LA and LNA by the action of Δ5- and Δ6-desaturase and elongase enzymes (Schmitz and Ecker, 2008; Wood et al., 2008). The main long-chain n-3 PUFA in the PL fraction of breast and thigh meat was docosapentaenoic acid (22:5n-3; DPA; Tables 4 and5). High dietary flaxseed significantly increased DPA content of breast meat PL after 16 d compared with birds not receiving dietary flaxseed supplementation. After 35 d, an overall increment of 39% in DPA content was obtained in this tissue. When low flaxseed was included in the diet, DPA content significantly increased after 24 d. By contrast, in thigh meat, DPA concentration did not significantly change over time with the low dietary treatment. However, the high dietary treatment significantly increased the DPA content at 35 d. In breast meat, EPA increased significantly only after 35 d with low flaxseed, but only 8 d was necessary to produce a significant change with high flaxseed. In thigh meat, the level of EPA significantly increased after 12 d with high flaxseed and after 16 d in the low flaxseed treatment. Docosahexaenoic acid did not significantly increase in breast meat. Although some statistical differences were found, the patterns were not related to duration.

These results are consistent with the theory that broilers convert dietary LNA to LC-PUFA, although the muscle deposition is low (Fritsche et al., 1991; An et al., 1997; Lopez-Ferrer et al., 2001a, 1999). Results also concur with Warnants et al. (1999), Gonzalez-Esquera and Leeson (2001), and Wood et al. (2008), who reported that n-3 and n-6 LC-PUFA are preferentially stored in the PL fraction compared to LNA. Lopez-Ferrer et al. (2001b) affirmed that all vegetable fat sources seem to be less effective than marine oils for enrichment of meat with long-chain n-3 PUFA–an issue stemming from differences in the fatty acid composition of these source materials. However, meat producers should be cautious in the use of fish oil because at concentrations higher than 1 to 2% in poultry diet, it can create organoleptic problems in meat (Hargis and Van Elswyk, 1993).

The 1.5-fold increase in total n-3 PUFA in the PL fraction of breast meat after 35 d was due to an increase of long-chain n-3 PUFA. Significant increases in total n-3 PUFA breast meat content occurred after 24 and 20 d depending on flax level (Table 4). In thigh meat, total n-3 PUFA PL content did not change significantly in any of the feeding periods, except in the high flaxseed treatment, in which n-3 PUFA content increased after 20 d (Table 5). No pattern of total n-6 PUFA in breast meat PL was observed in relation to duration. In thigh meat, a significant decrease of n-6 PUFA began from d 12 in the low flaxseed treatment.

The most important metabolite of LA is AA. Therefore, AA in PL membranes normally decreases when LC n-3 PUFA increases (Komprda et al., 2005). In the current study, this was also observed. Arachidonic acid significantly decreased in breast and thigh meat PL when long-chain n-3 PUFA increased due to dietary flaxseed (Tables 4 and5). The AA reduction in thigh meat PL explains why a reduction in total PUFA n-6 was observed. These results are consistent with the theory that LA and LNA compete for the same series of enzymes (desaturase and elongase). Long-chain PUFA, synthesized from LA and LNA mainly in the hepatocytes, and to a lesser extent in intestinal cells (Bezard et al., 1994), are normally assembled into PL that subsequently will form the shell enclosing the neutral core (TAG, cholesteryl ester, and lipid-soluble vitamins) of lipoproteins (Jonas, 2002). From liver and intestine, lipoproteins transport lipids to the peripheral tissue (e.g., muscles). Although fatty acids of the neutral core are mainly stored in the adipocytes located in the perimysium and used as a source of energy through β-lipid oxidation, LC-PUFA from PL are preferentially incorporated in muscle cell membranes (Bezard et al., 1994). Thus, the fatty acid profile of cell membranes tends to be similar to the membrane fatty acid composition found in lipoproteins (Jonas, 2002). For these reasons, the ratio 20:4n-6:20:3n-6 in muscle PL can be used to estimate Δ5-desaturase activity on the n-6 PUFA series in the liver (Storlein et al., 1995; Monteiro et al., 2006). In our study, a strong decrease in Δ5-desaturase activity was observed within 4 d of feeding flaxseed (Figure 1). However, after 10 d, a slight reduction in the enzymatic activity was observed. Because in breast meat PL the fatty acid 20:3n-6 was not detected, the ratio 20:4n-6:18:2n-6 was used to estimate the overall de-saturase and elongase activity on the n-6 PUFA series. Results (Figure 2) showed a constant linear decrease in enzymatic activity with duration of flaxseed feeding. The reduced Δ5-desaturase activity indicates that LNA suppressed bioconversion of AA from LA (Garg et al., 1988).

In breast and thigh PL, the n-6:n-3 ratio decreased with duration of dietary flaxseed (Table 4 and5). This reduction is a consequence of the significant increases in long-chain n-3 PUFA with duration of feeding flax-seed. In thigh meat, the reduction depends on both LC n-3 PUFA enrichment and total n-6 PUFA reduction.

TAG Fraction.

Seventeen and 16 fatty acids were detected in breast and thigh meat TAG, respectively. The primary fatty acid of this lipid fraction was oleic acid (18:1n-9) in both tissues (Tables 6,7 and 8). This fatty acid is more predominant in neutral lipids than in polar lipids (Wood et al., 2008). Erucic acid (22:1n-9) was detected only in breast TAG.

The SFA and monounsaturated fatty acid levels in the TAG fraction of the breast meat did not change in response to dietary flaxseed level or duration (Tables 6,7 and 8). Thigh meat had a significant increase in total PUFA content by d 12 (high flaxseed) or d 35 (low flax-seed) compared with birds that did not receive dietary flaxseed. This was not observed in breast meat TAG.

With the high level of flaxseed, LNA content was significantly increased with 8 d of supplementation in both breast and thigh meat compared with birds on the nonenriched control diet (Tables 6,7 and 8). With the low flaxseed ration, 16 d of feeding was necessary for a significant increase in breast meat LNA, but only 8 d for thigh meat. In both tissues, LNA represented 96 to 98% of the total n-3 PUFA content with both dietary flaxseed treatments. The greater LNA content of thigh compared with breast meat was presumably due to the higher amount of TAG in the thigh (Gonzalez-Esquerra and Leeson, 2001) and fits with the observation that LNA is mainly deposited in the TAG rather than in the PL lipid fraction (Gonzalez-Esquerra and Leeson, 2001). Results are also in agreement with the theory that the fatty acid profile of membrane PL is less affected by dietary fat composition than TAG fatty acids. This could be because changes in the PL fraction could seriously affect the fluidity of cell membranes, whereas changes in TAG are primarily related to energy storage rather than to cell membranes (Villaverde et al., 2006; Wood et al., 2008).

In both tissues, long-chain n-3 PUFA (EPA, DPA, and DHA) represented 2 to 4% of the total TAG n-3 PUFA content with both dietary flaxseed treatments. This percentage was lower than those found in the PL fraction of breast and thigh meat, in which long-chain n-3 PUFA accounted for 71 to 89% of total n-3 PUFA content. The high flaxseed diet triggered significant increases in EPA levels after 8 d in breast meat (Table 6) and after 4 d in thigh meat (Table 8). After 35 d, a 6-fold increase in breast meat EPA was observed for both high and low flaxseed supplementation. Similar results were found in the TAG fraction of thigh meat with a high and low level of flaxseed. Low and high dietary flaxseed increased DPA concentration in breast meat at 24 and 8 d, respectively, and in thigh meat at 8 and 4 d, respectively. Docosahexaenoic acid was not detected in the TAG fraction of breast meat until 35 or 20 d in the low and high flaxseed treatment, respectively. In thigh meat, DHA levels were continuously detected after 8 and 12 d, respectively.

During enrichment, total long-chain n-3 PUFA were deposited in both TAG and PL fatty acid fractions. Increments above 400% were found in breast and thigh meat TAG after 35 d of flaxseed supplementation, respectively. These values were higher than those found in the PL fraction (~50%). However, due to the baseline levels of long-chain n-3 PUFA being so low in the TAG fraction to begin with, even after enrichment the final level of long-chain n-3 PUFA was still lower than in the PL fraction. A high flaxseed supplementation for 24 d generated a deposition of 19.1 mg/100 g of thigh meat of long-chain n-3 PUFA; this amount was similar to those determined in the PL fraction of nonenriched breast and thigh meat (Tables 4 and5).

Total n-3 PUFA content in the TAG fraction was much higher than in PL fraction due to LNA deposition in both thigh and breast tissues. In breast muscle, total n-3 PUFA significantly increased by d 35 (low) or d 16 (high) (Table 6). In thigh muscle, total n-3 PUFA significantly increased by d 8 or d 4, with low or high dietary flaxseed diets, respectively (Tables 78). Our findings concur with Leskanich et al. (1993), who reported significant dietary n-3 PUFA effects on the corresponding fatty acid composition in the TAG fraction of pig muscle, and this occurred proportionally with the duration of the treatment.

Total n-6 PUFA in the TAG were not changed by dietary flaxseed in both tissues and remained higher then the n-3 PUFA content in spite of the dietary treatments. This could be explained by looking at the fatty acid profile of the diets (Table 2); LA and total n-6 PUFA content remained almost constant in relation to canola oil substitution with flaxseed.

In both tissues, the n-6:n-3 ratio in the TAG fraction decreased due to n-3 PUFA deposition with duration of feeding flaxseed (Tables 6,78). Simopoulos (2004) reported that an n-6:n-3 ratio below 4.0 promotes cardiovascular health in humans. In our experiment, only 4 d of duration was necessary to achieve values below 4 in both breast and thigh meat with high and low flax-seed supplementation, respectively.

Results clearly indicated that LNA was mainly concentrated in neutral lipids (TAG) compared with polar PL, found in cell membranes, and also suggested that this fatty acid was mainly used as a source of energy in muscle metabolism rather than structural fatty acids in PL membranes (Plourde and Cunnane, 2007). The major source of long-chain n-3 PUFA was in the PL fraction, leaving a limited amount of long-chain n-3 PUFA in the neutral lipid fraction, where significant increments were found. These findings coincide also with studies conducted in pig and bovine muscle enrichment (Warnants et al., 1999; Kronberg et al., 2006).

Duration Required in Labeling a Product “n-3 Enriched”

The n-3 PUFA content from total lipid tissue fatty acids analysis was used to determine the duration required to label a product “n-3 enriched” and is reported in Table 9. The broken-stick analysis yielded the following equations for breast meat n-3 enrichment:

graphic

graphic

This indicates that total n-3 PUFA concentrations in the breast meat increased at 7.91 mg/100 g per day that the birds received the low flaxseed diet, compared with 13.60 mg/100 g per day that the birds received the high flaxseed diet. Maximum concentrations of total n-3 PUFA reached the plateau of 399 mg/100 g in birds on the high flaxseed diets after 18.5 d, whereas in the low treatment, a plateau was not reached.

Broken-stick analysis indicated that the threshold level of 300 mg of total n-3 fatty acid per 100 g of meat required for labeling the meat as a source of n-3 fatty acids (CFIA, 2003) was reached in breast meat at 11.3 or 26.2 d in the high and low flaxseed treatments, respectively (Figure 3). These results are consistent with our previous trial (Zuidhof et al., 2009).

Another important aspect of this study is the confirmation that DPA was the most predominant long-chain n-3 PUFA of the entire lipid classes (Tables 456789). This result concurs with most of the studies conducted in pig and ruminant lipids (Specht-Overholt et al., 1997; Warnants et al., 1999; Riley et al., 2000; Kronberg et al., 2006; Scollan et al., 2006). By contrast, in poultry lipids, Crespo and Esteve-Garcia (2002), Shen et al. (2005), and Zelenka et al. (2008) found the same results, whereas other researchers (An et al., 1997; Lopez-Ferrer et al., 1999, 2001a) found DHA to be the main long-chain n-3 PUFA.

Flaxseed is a good source to enrich poultry meat with n-3 PUFA mainly due to LNA. Tissue structure influences the location of fatty acid deposition. Modifying the fatty acid profile of the diet primarily stimulates LNA enrichment in the TAG fraction of the meat, and a much smaller enrichment is observed in PL membranes. In broiler dark meat in which TAG is much more predominant than in breast meat, LNA enrichment was higher. Although long-chain n-3 PUFA content was increased in both lipid classes by flaxseed feeding, the levels of EPA, DPA, and DHA were of limited nutritional value.

To achieve adequate levels (300 mg/100 g of meat) to label breast meat as a source of n-3 fatty acids, birds need to be fed low and high flaxseed for 26.2 or 11.3 d, respectively. However, an important issue when considering n-3 PUFA claim for muscle foods is the lack of distinction among which n-3 PUFA fatty acids are the most effective in relation to human health. The US Food and Drug Administration (2004) gave qualified health claim status specifically to DHA and EPA and not to LNA. However, the Canadian Food Inspection Agency (2003) seems not to take into consideration the different bioactivity among these fatty acids.

Overall, this research project, from live performance (Zuidhof et al., 2009) to meat quality traits (Betti et al., 2009), may represent an important step in providing information about feeding strategies to enrich chicken meat products with n-3 PUFA. However, producers should understand that the rate of n-3 enrichment of dark meat is much faster, enabling enrichment without compromising live performance and meat functional properties due to longer periods of feeding ground flax-seed diets.

Table 1

Diet composition and nutrient content of diets containing control, low, and high levels of dietary enrichment with 0, 10, and 17% dietary ground flaxseed, respectively

 Starter (0 to 11 d) Grower (11 to 21 d) Finisher (21 to 35 d) 
Item Control Low Control Low High Control Low High 
1Omegaflax ground whole flaxseed meal (ADM Animal Health & Nutrition, Lethbridge, Alberta, Canada). 
2The microingredient mix contained (per kg of diet): iron, 100 mg; zinc, 80 mg; manganese, 70 mg; copper, 8.5 mg; iodine, 0.5 mg; selenium, 0.1 mg; vitamin A, 10,000 IU; vitamin D3, 2,500 IU; vitamin E, 50 IU; vitamin K (menadione), 2 mg; niacin, 65 mg; d-pantothenic acid, 14 mg; riboflavin, 5 mg; pyridoxine, 4 mg; thiamine, 2 mg; folic acid, 0.8 mg; biotin, 0.18 mg; vitamin B12, 0.015 mg; choline, 0 mg; Avizyme 1300 (Danisco Animal Nutrition, Marlborough, Wiltshire, UK), 500 mg; bacitracin methylene disalicylate (BMD 110 G, Alpharma, Mississauga, Ontario, Canada), 500 mg; choline chloride, 400 mg; Sacox 120 (Intervet Canada, Whitby, Ontario, Canada), 500 mg. 
Ingredient, % 
    Corn 5.000 5.000 30.42 5.00 — 39.75 25.00 25.00 
    Corn gluten meal 1.00 5.00  5.00 7.27 — — — 
    Soybean meal 26.80 15.61 22.67 4.83  21.77 17.09 15.55 
    Wheat bran 10.69 — 21.37 6.14 4.51 18.00 5.87 — 
    Calcium carbonate 1.43 1.38 1.36 1.30 1.27 1.30 1.21 1.16 
    Dicalcium phosphate 1.82 1.95 1.50 1.67 1.68 1.41 1.52 1.59 
    NaCl 0.47 0.42 0.49 0.45 0.39 0.50 0.47 0.42 
    l-Lysine 0.33 0.30 0.32 0.36 0.24 0.26 — — 
    dl-Methionine 0.29 0.01 0.37 0.01 — 0.32 0.05 — 
    l-Threonine 0.08 — 0.08 — — 0.06 — — 
    Wheat 43.67 55.39 10.32 59.50 61.80 5.62 30.19 31.51 
    Ground flaxseed meal1 — 10.00 — 10.00 17.00 — 10.00 17.00 
    Canola oil 6.97 3.48 9.66 4.30 4.39 9.56 7.15 6.33 
    Microingredients2 1.45 1.45 1.45 1.45 1.45 1.45 1.45 1.45 
Calculated analysis 
    ME, kcal/kg 3,086 3,086 3,110 3,110 3,110 3,196 3,196 3,196 
    CP, % 23.0 22.0 19.0 18.0 18.0 18.0 18.0 18.0 
    Crude fat, % 8.69 8.47 12.00 10.00 12.69 12.00 13.00 14.75 
    Crude fiber, % 3.30 3.15 3.70 5.46 7.08 3.38 5.18 6.48 
    Ca, % 1.00 1.00 0.90 0.90 0.90 0.85 0.85 0.85 
    Available P, % 0.50 0.50 0.45 0.45 0.45 0.42 0.42 0.42 
    Met + Cys, % 0.97 1.00 0.85 0.85 1.00 0.80 0.80 0.91 
    Met, % 0.64 0.53 0.64 0.47 0.56 0.59 0.45 0.48 
    Lys, % 1.35 1.42 1.18 1.18 1.22 1.09 1.13 1.33 
    Try, % 0.31 0.42 0.26 0.36 0.45 0.25 0.38 0.48 
    Thr, % 0.87 1.00 0.76 0.82 1.00 0.72 0.91 1.10 
    Arg, % 1.46 1.99 1.28 1.65 2.11 1.22 1.90 2.41 
 Starter (0 to 11 d) Grower (11 to 21 d) Finisher (21 to 35 d) 
Item Control Low Control Low High Control Low High 
1Omegaflax ground whole flaxseed meal (ADM Animal Health & Nutrition, Lethbridge, Alberta, Canada). 
2The microingredient mix contained (per kg of diet): iron, 100 mg; zinc, 80 mg; manganese, 70 mg; copper, 8.5 mg; iodine, 0.5 mg; selenium, 0.1 mg; vitamin A, 10,000 IU; vitamin D3, 2,500 IU; vitamin E, 50 IU; vitamin K (menadione), 2 mg; niacin, 65 mg; d-pantothenic acid, 14 mg; riboflavin, 5 mg; pyridoxine, 4 mg; thiamine, 2 mg; folic acid, 0.8 mg; biotin, 0.18 mg; vitamin B12, 0.015 mg; choline, 0 mg; Avizyme 1300 (Danisco Animal Nutrition, Marlborough, Wiltshire, UK), 500 mg; bacitracin methylene disalicylate (BMD 110 G, Alpharma, Mississauga, Ontario, Canada), 500 mg; choline chloride, 400 mg; Sacox 120 (Intervet Canada, Whitby, Ontario, Canada), 500 mg. 
Ingredient, % 
    Corn 5.000 5.000 30.42 5.00 — 39.75 25.00 25.00 
    Corn gluten meal 1.00 5.00  5.00 7.27 — — — 
    Soybean meal 26.80 15.61 22.67 4.83  21.77 17.09 15.55 
    Wheat bran 10.69 — 21.37 6.14 4.51 18.00 5.87 — 
    Calcium carbonate 1.43 1.38 1.36 1.30 1.27 1.30 1.21 1.16 
    Dicalcium phosphate 1.82 1.95 1.50 1.67 1.68 1.41 1.52 1.59 
    NaCl 0.47 0.42 0.49 0.45 0.39 0.50 0.47 0.42 
    l-Lysine 0.33 0.30 0.32 0.36 0.24 0.26 — — 
    dl-Methionine 0.29 0.01 0.37 0.01 — 0.32 0.05 — 
    l-Threonine 0.08 — 0.08 — — 0.06 — — 
    Wheat 43.67 55.39 10.32 59.50 61.80 5.62 30.19 31.51 
    Ground flaxseed meal1 — 10.00 — 10.00 17.00 — 10.00 17.00 
    Canola oil 6.97 3.48 9.66 4.30 4.39 9.56 7.15 6.33 
    Microingredients2 1.45 1.45 1.45 1.45 1.45 1.45 1.45 1.45 
Calculated analysis 
    ME, kcal/kg 3,086 3,086 3,110 3,110 3,110 3,196 3,196 3,196 
    CP, % 23.0 22.0 19.0 18.0 18.0 18.0 18.0 18.0 
    Crude fat, % 8.69 8.47 12.00 10.00 12.69 12.00 13.00 14.75 
    Crude fiber, % 3.30 3.15 3.70 5.46 7.08 3.38 5.18 6.48 
    Ca, % 1.00 1.00 0.90 0.90 0.90 0.85 0.85 0.85 
    Available P, % 0.50 0.50 0.45 0.45 0.45 0.42 0.42 0.42 
    Met + Cys, % 0.97 1.00 0.85 0.85 1.00 0.80 0.80 0.91 
    Met, % 0.64 0.53 0.64 0.47 0.56 0.59 0.45 0.48 
    Lys, % 1.35 1.42 1.18 1.18 1.22 1.09 1.13 1.33 
    Try, % 0.31 0.42 0.26 0.36 0.45 0.25 0.38 0.48 
    Thr, % 0.87 1.00 0.76 0.82 1.00 0.72 0.91 1.10 
    Arg, % 1.46 1.99 1.28 1.65 2.11 1.22 1.90 2.41 
Table 2

Fatty acid profile (mg/g of diet) of experimental diets

 Starter Grower Finisher  
Item 0% Flax 10% Flax 0% Flax 10% Flax 17% Flax 0% Flax 10% Flax 17% Flax SE 
a–cMeans within fatty acids and within dietary phase with no common superscript are significantly different (P < 0.05). 
1The following fatty acids were not detected: 20:0, 20:2n-6, 20:3n-6, 20:4n-6, 20:5n-3, 22:0, 22:5n-3, 22:6 n-3. 
2ND = not detected. 
3SFA = saturated fatty acids; SFA levels were calculated as 14:0 + 16:0 + 18:0 + 20:0 + 22:0. 
4MUFA = monounsaturated fatty acids; MUFA levels were calculated as 16:1n-7 + 18:1n-7 + 18:1n-9 + 22:1n-9. 
5PUFA = polyunsaturated fatty acids; PUFA levels were calculated as 18:2n-6 + 18:3n-3 + 18:3n-6 + arachidonic acid + 22:4n-6. 
6Total n-3 equal to a-linolenic acid. 
7Total n-6 was calculated as linoleic acid +18:3n-6 + arachidonic acid + 22:4. 
Fatty acid1 ——— mg/g of diet ——— 
    14:0 0.0538a 0.0480a 0.0591a 0.0491a 0.0475a 0.0614a 0.0513a 0.0565a 0.0050 
    15:0 0.0302a 0.0257a 0.0318a 0.0288a 0.0271a 0.0226a 0.0230a 0.0267a 0.0030 
    16:0 5.47a 5.68a 5.49a 5.87a 5.55a 5.18ab 5.20b 5.81a 0.22 
    16:1n-7 0.181a 0.117b 0.189a 0.159ab 0.126b 0.240a 0.159b 0.180b 0.014 
    18:0 1.45b 2.09a 1.28b 1.84a 1.90a 1.19b 1.57a 1.83a 0.12 
    18:1n-7 1.311a 0.733b 1.540a 0.755b ND2 ND 0.976a ND 0.050 
    18:1n-9 33.1a 23.9b 38.0a 26.1b 23.3b 36.2a 26.5c 30.8b 1.8 
    18:2n-6 20.0 19.9 22.5 21.3 19.4 21.9ab 19.9b 22.2a 0.1 
    18:3n-3 5.30b 23.5a 6.80c 22.7b 27.4a 5.90c 18.8b 30.9a 0.80 
    18:3n-6 0.0290a 0.129a 0.162a 0.020b 0.089ab 0.189ab 0.092b 0.189a 0.036 
    22:1n-9 0.186a 0.162a 0.166a 0.145a 0.136a 0.114a 0.126a 0.132a 0.012 
    22:4n-6 0.1099a 0.1086a 0.0849a 0.0903a 0.0864a 0.0448b 0.0741ab 0.0843a 0.0112 
SFA3 7.19 7.95 7.04 7.95 7.65 6.69b 7.00b 7.90a 0.31 
MUFA4 36.8a 26.2b 42.2a 28.5b 24.7b 38.5a 29.4b 32.5b 1.9 
PUFA5 25.5b 43.7a 29.6b 44.2a 47.0a 28.1c 38.9b 53.4a 1.6 
Total n-36 5.30b 23.5a 6.80c 22.7b 27.4a 5.90c 18.8b 30.9a 0.8 
Total n-67 20.1 20.2 22.8a 21.4ab 19.5b 22.1ab 20.0b 22.5a 0.1 
 Starter Grower Finisher  
Item 0% Flax 10% Flax 0% Flax 10% Flax 17% Flax 0% Flax 10% Flax 17% Flax SE 
a–cMeans within fatty acids and within dietary phase with no common superscript are significantly different (P < 0.05). 
1The following fatty acids were not detected: 20:0, 20:2n-6, 20:3n-6, 20:4n-6, 20:5n-3, 22:0, 22:5n-3, 22:6 n-3. 
2ND = not detected. 
3SFA = saturated fatty acids; SFA levels were calculated as 14:0 + 16:0 + 18:0 + 20:0 + 22:0. 
4MUFA = monounsaturated fatty acids; MUFA levels were calculated as 16:1n-7 + 18:1n-7 + 18:1n-9 + 22:1n-9. 
5PUFA = polyunsaturated fatty acids; PUFA levels were calculated as 18:2n-6 + 18:3n-3 + 18:3n-6 + arachidonic acid + 22:4n-6. 
6Total n-3 equal to a-linolenic acid. 
7Total n-6 was calculated as linoleic acid +18:3n-6 + arachidonic acid + 22:4. 
Fatty acid1 ——— mg/g of diet ——— 
    14:0 0.0538a 0.0480a 0.0591a 0.0491a 0.0475a 0.0614a 0.0513a 0.0565a 0.0050 
    15:0 0.0302a 0.0257a 0.0318a 0.0288a 0.0271a 0.0226a 0.0230a 0.0267a 0.0030 
    16:0 5.47a 5.68a 5.49a 5.87a 5.55a 5.18ab 5.20b 5.81a 0.22 
    16:1n-7 0.181a 0.117b 0.189a 0.159ab 0.126b 0.240a 0.159b 0.180b 0.014 
    18:0 1.45b 2.09a 1.28b 1.84a 1.90a 1.19b 1.57a 1.83a 0.12 
    18:1n-7 1.311a 0.733b 1.540a 0.755b ND2 ND 0.976a ND 0.050 
    18:1n-9 33.1a 23.9b 38.0a 26.1b 23.3b 36.2a 26.5c 30.8b 1.8 
    18:2n-6 20.0 19.9 22.5 21.3 19.4 21.9ab 19.9b 22.2a 0.1 
    18:3n-3 5.30b 23.5a 6.80c 22.7b 27.4a 5.90c 18.8b 30.9a 0.80 
    18:3n-6 0.0290a 0.129a 0.162a 0.020b 0.089ab 0.189ab 0.092b 0.189a 0.036 
    22:1n-9 0.186a 0.162a 0.166a 0.145a 0.136a 0.114a 0.126a 0.132a 0.012 
    22:4n-6 0.1099a 0.1086a 0.0849a 0.0903a 0.0864a 0.0448b 0.0741ab 0.0843a 0.0112 
SFA3 7.19 7.95 7.04 7.95 7.65 6.69b 7.00b 7.90a 0.31 
MUFA4 36.8a 26.2b 42.2a 28.5b 24.7b 38.5a 29.4b 32.5b 1.9 
PUFA5 25.5b 43.7a 29.6b 44.2a 47.0a 28.1c 38.9b 53.4a 1.6 
Total n-36 5.30b 23.5a 6.80c 22.7b 27.4a 5.90c 18.8b 30.9a 0.8 
Total n-67 20.1 20.2 22.8a 21.4ab 19.5b 22.1ab 20.0b 22.5a 0.1 
Table 3

Statistical significance of treatment effects for the fatty acid profile

 Breast meat Thigh meat 
 Phospholipids Triacylglycerols Phospholipids Triacylglycerols 
Item Duration Level Duration × level Duration Level Duration × level Duration Level Duration × level Duration Level Duration × level 
1ND = not detected. 
2SFA = saturated fatty acids. 
3MUFA = monounsaturated fatty acids. 
4PUFA = polyunsaturated fatty acids. 
Fatty acid 
    14:0 0.1842 0.6264 0.2290 0.0742 0.1658 0.0422 0.1447 <0.0001 0.0032 0.0001 <0.0001 <0.0001 
    16:0 0.0010 0.0017 0.0449 0.0295 0.0917 0.0148 0.4044 0.2305 0.0557 <0.0001 <0.0001 0.0001 
    16:1n-7 0.0002 0.0001 <0.0001 0.0021 0.0011 0.0013 0.1741 0.0122 0.0398 <0.0001 <0.0001 <0.0001 
    18:0 <0.0001 <0.0001 0.0003 0.0515 0.8313 0.0350 0.0008 <0.0001 <0.0001 0.0007 0.0078 0.0084 
    18:1n-7 <0.0001 0.3291 0.0368 0.0751 0.5135 0.0285 <0.0001 0.1049 0.0198 0.0310 0.0014 0.0030 
    18:1n-9 0.0017 0.0006 0.0066 0.0545 0.7782 0.0295 0.5550 0.1872 0.2188 0.0107 0.0081 0.0071 
    18:2n-6 <0.0001 <0.0001 0.0002 0.0731 0.2317 0.0593 0.0172 0.0086 0.0030 0.0777 0.3887 0.0503 
    18:3n-3 0.0111 0.0046 0.0060 <0.0001 <0.0001 0.0573 0.0561 0.0103 0.1717 <0.0001 <0.0001 0.0783 
    18:3n-6 ND1 ND ND ND ND ND ND ND ND 0.4670 0.2791 0.0194 
    20:0 ND ND ND ND ND ND ND ND ND <0.0001 <0.0001 0.0008 
    20:2n-6 <0.0001 0.0014 0.0002 0.2315 0.7532 0.0577 <0.0001 0.0085 <0.0001 0.0091 0.0003 0.0047 
    20:3n-6 ND ND ND ND ND ND 0.3505 0.244 0.0184 <0.0001 0.7144 0.0619 
    20:4n-6 <0.0001 <0.0001 <0.0001 0.0029 0.0002 0.0011 <0.0001 0.0577 0.0013 0.0342 0.0001 <0.0001 
    20:5n-3 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 0.2037 <0.0001 <0.0001 0.0078 <0.0001 <0.0001 <0.0001 
    22:1 ND ND ND <0.0001 0.0042 0.0802 ND ND ND ND ND ND 
    22:4n-6 ND ND ND ND ND ND <0.0001 <0.0001 0.0029 ND ND ND 
    22:5n-3 <0.0001 <0.0001 0.0006 <0.0001 <0.0001 0.0609 0.0008 0.0142 0.1324 <0.0001 0.0001 0.0003 
    22:6n-3 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 0.0108 <0.0001 <0.0001 <0.0001 0.0117 0.0002 
SFA2 0.0004 <0.0001 0.0062 0.0344 0.1924 0.0189 0.0417 0.0390 0.0034 <0.0001 <0.0001 0.0003 
MUFA3 0.0027 0.0041 0.0106 0.0489 0.5737 0.0250 0.2948 0.2295 0.2237 0.0046 0.0015 0.0029 
PUFA4 <0.0001 <0.0001 0.0009 0.0054 0.0170 0.0893 0.0803 0.0026 0.0029 <0.0001 0.0006 0.2162 
Total n-3 <0.0001 <0.0001 0.0003 <0.0001 <0.0001 0.0615 0.0006 0.0001 0.0154 <0.0001 <0.0001 0.0289 
Total n-6 <0.0001 <0.0001 0.0012 0.0720 0.2219 0.0584 0.0005 0.0146 0.0012 0.0803 0.3901 0.0512 
n-6:n-3 <0.0001 <0.0001 0.0024 <0.0001 <0.0001 0.0002 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 
 Breast meat Thigh meat 
 Phospholipids Triacylglycerols Phospholipids Triacylglycerols 
Item Duration Level Duration × level Duration Level Duration × level Duration Level Duration × level Duration Level Duration × level 
1ND = not detected. 
2SFA = saturated fatty acids. 
3MUFA = monounsaturated fatty acids. 
4PUFA = polyunsaturated fatty acids. 
Fatty acid 
    14:0 0.1842 0.6264 0.2290 0.0742 0.1658 0.0422 0.1447 <0.0001 0.0032 0.0001 <0.0001 <0.0001 
    16:0 0.0010 0.0017 0.0449 0.0295 0.0917 0.0148 0.4044 0.2305 0.0557 <0.0001 <0.0001 0.0001 
    16:1n-7 0.0002 0.0001 <0.0001 0.0021 0.0011 0.0013 0.1741 0.0122 0.0398 <0.0001 <0.0001 <0.0001 
    18:0 <0.0001 <0.0001 0.0003 0.0515 0.8313 0.0350 0.0008 <0.0001 <0.0001 0.0007 0.0078 0.0084 
    18:1n-7 <0.0001 0.3291 0.0368 0.0751 0.5135 0.0285 <0.0001 0.1049 0.0198 0.0310 0.0014 0.0030 
    18:1n-9 0.0017 0.0006 0.0066 0.0545 0.7782 0.0295 0.5550 0.1872 0.2188 0.0107 0.0081 0.0071 
    18:2n-6 <0.0001 <0.0001 0.0002 0.0731 0.2317 0.0593 0.0172 0.0086 0.0030 0.0777 0.3887 0.0503 
    18:3n-3 0.0111 0.0046 0.0060 <0.0001 <0.0001 0.0573 0.0561 0.0103 0.1717 <0.0001 <0.0001 0.0783 
    18:3n-6 ND1 ND ND ND ND ND ND ND ND 0.4670 0.2791 0.0194 
    20:0 ND ND ND ND ND ND ND ND ND <0.0001 <0.0001 0.0008 
    20:2n-6 <0.0001 0.0014 0.0002 0.2315 0.7532 0.0577 <0.0001 0.0085 <0.0001 0.0091 0.0003 0.0047 
    20:3n-6 ND ND ND ND ND ND 0.3505 0.244 0.0184 <0.0001 0.7144 0.0619 
    20:4n-6 <0.0001 <0.0001 <0.0001 0.0029 0.0002 0.0011 <0.0001 0.0577 0.0013 0.0342 0.0001 <0.0001 
    20:5n-3 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 0.2037 <0.0001 <0.0001 0.0078 <0.0001 <0.0001 <0.0001 
    22:1 ND ND ND <0.0001 0.0042 0.0802 ND ND ND ND ND ND 
    22:4n-6 ND ND ND ND ND ND <0.0001 <0.0001 0.0029 ND ND ND 
    22:5n-3 <0.0001 <0.0001 0.0006 <0.0001 <0.0001 0.0609 0.0008 0.0142 0.1324 <0.0001 0.0001 0.0003 
    22:6n-3 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 0.0108 <0.0001 <0.0001 <0.0001 0.0117 0.0002 
SFA2 0.0004 <0.0001 0.0062 0.0344 0.1924 0.0189 0.0417 0.0390 0.0034 <0.0001 <0.0001 0.0003 
MUFA3 0.0027 0.0041 0.0106 0.0489 0.5737 0.0250 0.2948 0.2295 0.2237 0.0046 0.0015 0.0029 
PUFA4 <0.0001 <0.0001 0.0009 0.0054 0.0170 0.0893 0.0803 0.0026 0.0029 <0.0001 0.0006 0.2162 
Total n-3 <0.0001 <0.0001 0.0003 <0.0001 <0.0001 0.0615 0.0006 0.0001 0.0154 <0.0001 <0.0001 0.0289 
Total n-6 <0.0001 <0.0001 0.0012 0.0720 0.2219 0.0584 0.0005 0.0146 0.0012 0.0803 0.3901 0.0512 
n-6:n-3 <0.0001 <0.0001 0.0024 <0.0001 <0.0001 0.0002 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 
Table 4

Fatty acid profile (mg of fatty acids/100 g of meat) in breast meat phospholipids

 Low (10% flaxseed) High (17% flaxseed)  
Item 0 d 4 d 8 d 12 d 16 d 20 d 24 d 35 d 0 d 4 d 8 d 12 d 16 d 20 d 24 d 35 d SE 
a–hMeans within a row with no common superscript are significantly different (P < 0.05). 
1SFA = saturated fatty acids. 
2MUFA = monounsaturated fatty acids. 
3PUFA = polyunsaturated fatty acids. 
Fatty acid 
    14:0 1.03 1.16 1.02 1.05 1.18 1.25 1.16 1.15 1.15 0.97 1.09 1.08 1.17 1.11 1.19 1.14 0.06 
    16:0 66.60abc 62.62bc 60.90bc 56.52c 67.04abc 62.29bc 63.31bc 73.24ab 67.93abc 65.86abc 65.36bc 60.75bc 66.58abc 80.02a 71.00ab 72.93ab 2.52 
    16:1n-7 1.85bcde 1.59e 1.15e 1.59e 2.46abc 2.68a 1.69de 2.52ab 1.41e 1.12e 1.86bcde 2.36abcd 1.30e 1.48e 1.58e 1.70cde 0.14 
    18:0 33.10cde 31.04def 31.96cdef 27.11ef 31.19def 25.25f 36.85abcd 36.66abcd 37.30abcd 37.17abcd 33.24cde 32.11cdef 35.64bcd 43.84a 43.05ab 39.11abc 1.34 
    18:1n-7 17.25ab 14.06abcd 16.23abc 12.50d 13.83bcd 13.50cd 12.50d 16.25abc 17.59a 13.74bcd 15.71abcd 13.77bcd 14.77abcd 15.73abcd 13.77bcd 13.56cd 0.63 
    18:1n-9 68.27abcd 63.23bcd 62.56bcd 58.77d 74.02ab 66.66abcd 60.60cd 78.01a 69.10abcd 67.39abcd 72.72abc 72.54abc 68.82abcd 74.66ab 70.31abcd 75.11ab 2.27 
    18:2n-6 68.61bc 59.77cdef 54.88def 51.88f 63.93bcdef 54.28ef 64.44bcde 74.57ab 67.18bcd 63.70bcdef 63.70bcdef 62.37bcdef 74.39ab 82.49a 83.93a 84.84a 2.19 
    18:3n-3 2.76abc 2.74abc 2.35bc 2.09c 2.51abc 2.34bc 3.02ab 3.07ab 2.45abc 2.43abc 2.87abc 2.88abc 2.87abc 3.33a 2.97abc 3.21ab 0.16 
    20:2n-6 1.19h 1.69defgh 1.53efgh 1.36fgh 1.96cdefgh 3.01a 1.99bcdefg 2.49abc 1.34fgh 1.24gh 2.29abcde 2.47abcd 2.06bcdef 2.46abcd 2.75abc 2.78ab 0.14 
    20:4n-6 20.64b 17.83bcde 19.56bcd 14.04e 15.24e 9.64f 17.40bcde 14.04e 24.89a 25.75a 20.27bc 15.82de 17.06bcde 19.09bcd 15.17e 16.54cde 0.67 
    20:5n-3 3.14fg 3.18fg 2.41g 3.58efg 4.10def 4.36def 4.41def 6.02abc 2.30g 3.46fg 4.91cde 6.89a 5.39bcd 6.48ab 6.4ab 6.41ab 0.24 
    22:5n-3 8.72f 8.66f 9.688def 9.31ef 10.68cdef 9.76def 12.40bcde 14.37ab 9.95def 12.37bcde 13.74bc 12.46bcd 13.72bc 17.46a 14.77ab 15.44ab 0.55 
    22:6n-3 5.01cdef 4.76cdef 6.18bcde 4.44def 4.13f 4.29ef 6.55bc 6.26bcd 7.65b 10.29a 6.18bcde 5.93bcdef 6.09bcde 9.61a 7.465b 7.22b 0.34 
SFA1 100.7bcde 94.83bcde 93.88cde 84.68e 99.42bcde 88.78de 101.3bcde 111.1abc 106.4abcd 104.0bcde 99.70bcde 93.93cde 103.4bcde 125.0a 115.2ab 113.2abc 3.6 
MUFA2 87.36abcd 78.89bcd 79.94bcd 72.85d 90.30abc 82.83abcd 74.79cd 96.78a 88.09abcd 82.26abcd 90.28abc 88.67abcd 84.90abcd 91.87ab 85.66abcd 90.37abc 2.86 
PUFA3 110.1def 98.63efgh 96.60fgh 86.71h 102.5defgh 87.68gh 110.2def 120.8abcd 115.8bcdef 119.2bcde 114.0cdef 108.8defg 121.6abcd 140.9a 133.5abc 136.4ab 3.7 
Total n-3 19.63e 19.34e 20.63de 19.42e 21.42de 20.75de 26.38bcd 29.73b 22.35cde 28.56b 27.70bc 28.17bc 28.06bc 36.87a 31.61ab 32.28ab 2.81 
Total n-6 90.43abcd 79.29cde 75.97de 67.29e 81.13cde 66.93e 83.83cd 91.10abcd 93.40abc 90.68abcd 86.26bcd 80.66cde 93.50abc 104.0a 101.8ab 104.2a 1.1 
n-6:n-3 4.61a 4.13ab 3.68bcd 3.46cde 3.79bc 3.22cdef 3.18def 3.06ef 4.19ab 3.18def 3.11def 2.86ef 3.33cdef 2.82f 3.22cdef 3.23cdef 0.10 
 Low (10% flaxseed) High (17% flaxseed)  
Item 0 d 4 d 8 d 12 d 16 d 20 d 24 d 35 d 0 d 4 d 8 d 12 d 16 d 20 d 24 d 35 d SE 
a–hMeans within a row with no common superscript are significantly different (P < 0.05). 
1SFA = saturated fatty acids. 
2MUFA = monounsaturated fatty acids. 
3PUFA = polyunsaturated fatty acids. 
Fatty acid 
    14:0 1.03 1.16 1.02 1.05 1.18 1.25 1.16 1.15 1.15 0.97 1.09 1.08 1.17 1.11 1.19 1.14 0.06 
    16:0 66.60abc 62.62bc 60.90bc 56.52c 67.04abc 62.29bc 63.31bc 73.24ab 67.93abc 65.86abc 65.36bc 60.75bc 66.58abc 80.02a 71.00ab 72.93ab 2.52 
    16:1n-7 1.85bcde 1.59e 1.15e 1.59e 2.46abc 2.68a 1.69de 2.52ab 1.41e 1.12e 1.86bcde 2.36abcd 1.30e 1.48e 1.58e 1.70cde 0.14 
    18:0 33.10cde 31.04def 31.96cdef 27.11ef 31.19def 25.25f 36.85abcd 36.66abcd 37.30abcd 37.17abcd 33.24cde 32.11cdef 35.64bcd 43.84a 43.05ab 39.11abc 1.34 
    18:1n-7 17.25ab 14.06abcd 16.23abc 12.50d 13.83bcd 13.50cd 12.50d 16.25abc 17.59a 13.74bcd 15.71abcd 13.77bcd 14.77abcd 15.73abcd 13.77bcd 13.56cd 0.63 
    18:1n-9 68.27abcd 63.23bcd 62.56bcd 58.77d 74.02ab 66.66abcd 60.60cd 78.01a 69.10abcd 67.39abcd 72.72abc 72.54abc 68.82abcd 74.66ab 70.31abcd 75.11ab 2.27 
    18:2n-6 68.61bc 59.77cdef 54.88def 51.88f 63.93bcdef 54.28ef 64.44bcde 74.57ab 67.18bcd 63.70bcdef 63.70bcdef 62.37bcdef 74.39ab 82.49a 83.93a 84.84a 2.19 
    18:3n-3 2.76abc 2.74abc 2.35bc 2.09c 2.51abc 2.34bc 3.02ab 3.07ab 2.45abc 2.43abc 2.87abc 2.88abc 2.87abc 3.33a 2.97abc 3.21ab 0.16 
    20:2n-6 1.19h 1.69defgh 1.53efgh 1.36fgh 1.96cdefgh 3.01a 1.99bcdefg 2.49abc 1.34fgh 1.24gh 2.29abcde 2.47abcd 2.06bcdef 2.46abcd 2.75abc 2.78ab 0.14 
    20:4n-6 20.64b 17.83bcde 19.56bcd 14.04e 15.24e 9.64f 17.40bcde 14.04e 24.89a 25.75a 20.27bc 15.82de 17.06bcde 19.09bcd 15.17e 16.54cde 0.67 
    20:5n-3 3.14fg 3.18fg 2.41g 3.58efg 4.10def 4.36def 4.41def 6.02abc 2.30g 3.46fg 4.91cde 6.89a 5.39bcd 6.48ab 6.4ab 6.41ab 0.24 
    22:5n-3 8.72f 8.66f 9.688def 9.31ef 10.68cdef 9.76def 12.40bcde 14.37ab 9.95def 12.37bcde 13.74bc 12.46bcd 13.72bc 17.46a 14.77ab 15.44ab 0.55 
    22:6n-3 5.01cdef 4.76cdef 6.18bcde 4.44def 4.13f 4.29ef 6.55bc 6.26bcd 7.65b 10.29a 6.18bcde 5.93bcdef 6.09bcde 9.61a 7.465b 7.22b 0.34 
SFA1 100.7bcde 94.83bcde 93.88cde 84.68e 99.42bcde 88.78de 101.3bcde 111.1abc 106.4abcd 104.0bcde 99.70bcde 93.93cde 103.4bcde 125.0a 115.2ab 113.2abc 3.6 
MUFA2 87.36abcd 78.89bcd 79.94bcd 72.85d 90.30abc 82.83abcd 74.79cd 96.78a 88.09abcd 82.26abcd 90.28abc 88.67abcd 84.90abcd 91.87ab 85.66abcd 90.37abc 2.86 
PUFA3 110.1def 98.63efgh 96.60fgh 86.71h 102.5defgh 87.68gh 110.2def 120.8abcd 115.8bcdef 119.2bcde 114.0cdef 108.8defg 121.6abcd 140.9a 133.5abc 136.4ab 3.7 
Total n-3 19.63e 19.34e 20.63de 19.42e 21.42de 20.75de 26.38bcd 29.73b 22.35cde 28.56b 27.70bc 28.17bc 28.06bc 36.87a 31.61ab 32.28ab 2.81 
Total n-6 90.43abcd 79.29cde 75.97de 67.29e 81.13cde 66.93e 83.83cd 91.10abcd 93.40abc 90.68abcd 86.26bcd 80.66cde 93.50abc 104.0a 101.8ab 104.2a 1.1 
n-6:n-3 4.61a 4.13ab 3.68bcd 3.46cde 3.79bc 3.22cdef 3.18def 3.06ef 4.19ab 3.18def 3.11def 2.86ef 3.33cdef 2.82f 3.22cdef 3.23cdef 0.10 
Table 5

Fatty acid profile (mg of fatty acids/100 g of meat) in thigh meat phospholipids

 Low (10% flaxseed) High (17% flaxseed) 
Item 0 d 4 d 8 d 12 d 16 d 20 d 24 d 35 d 0 d 4 d 8 d 12 d 16 d 20 d 24 d 35 d SE 
a–hMeans within a row with no common superscript are significantly different (P < 0.05). 
1ND = not detected. 
2SFA = saturated fatty acids. 
3MUFA = monounsaturated fatty acids. 
4PUFA = polyunsaturated fatty acids. 
Fatty acids 
    14:0 ND1 ND ND ND ND 0.51bc 0.35bc 0.20bc 1.08ab 1.13ab 1.13ab 1.05abc 2.09a 1.13ab 1.01bc 0.92bc 0.19 
    16:0 69.25 59.12 66.65 61.13 64.19 60.55 57.97 53.75 63.65 61.91 51.13 57.31 52.49 62.73 63.05 61.98 3.68 
    16:1n-7 2.81 2.89 2.08 2.11 2.68 2.32 2.80 2.08 2.68 1.44 2.29 2.21 1.17 3.05 1.30 1.46 0.37 
    18:0 67.87ab 47.44cd 55.52abcd 44.29d 45.86d 47.57cd 45.61d 43.54d 60.33abcd 53.54bcd 44.62d 53.34bcd 65.93ab 48.86cd 63.83abc 71.84a 2.97 
    18:1n-7 16.19ab 12.44bcd 13.47abc 10.94cd 10.86cd 10.24cd 9.53d 10.33cd 16.48a 13.49abc 10.03cd 12.09cd 12.25cd 10.62cd 12.02cd 11.67cd 0.67 
    18:1n-9 69.44 61.98 75.00 60.96 64.20 61.64 59.12 55.75 76.80 67.40 58.62 65.63 58.06 70.72 79.42 66.12 6.29 
    18:2n-6 99.47ab 77.34abc 95.97abc 74.65abc 78.87abc 81.54abc 69.26c 71.47bc 101.20a 81.76abc 71.03bc 82.24abc 97.49abc 84.05abc 99.68ab 93.11abc 5.18 
    18:3n-3 4.68b 5.49ab 11.11ab 7.67ab 8.25ab 8.30ab 7.21ab 7.20ab 5.56ab 6.08ab 8.60ab 12.12ab 9.19ab 15.35ab 18.67a 11.92ab 2.37 
    20:2n-6 2.35a ND 2.09ab 1.50abc 1.53abc 1.12bc 0.45cd ND 1.63ab 1.79ab 1.36abc 1.15bc 1.37abc 1.29abc 1.40abc 1.41abc 0.20 
    20:3n-6 2.74a 2.42ab 2.59ab 2.35ab 2.56ab 2.01ab 2.27ab 1.73b 2.02 2.05 2.14 2.37 2.24 2.49 2.29 2.26 0.17 
    20:4n-6 33.78a 24.00bcd 26.48bc 20.55cde 20.07cde 19.15de 18.38de 15.48e 30.58ab 26.59abc 20.35cde 22.88cd 24.58bcd 18.73de 20.85cde 23.79bcd 1.28 
    20:5n-3 2.35gh 2.89fgh 3.66efgh 3.86defgh 4.95cdef 4.45cdefg 5.24bcde 4.89cdef 2.20h 2.33gh 4.01cdefgh 5.59abcde 6.14abc 5.88abcd 7.37ab 7.62a 0.39 
    22:4n-6 5.51a 3.72b 3.41bc 2.96bcd 2.51cde 1.47ef 1.98def 1.38ef 3.59bc 3.26bc 1.97def 2.11def 1.47ef 1.34f 1.29f 1.38ef 0.20 
    22:5n-3 10.56abcd 8.52d 10.44abcd 10.72abcd 12.51abcd 10.91abcd 11.09abcd 11.59abcd 9.02cd 9.53bcd 10.10abcd 12.52abcd 12.68abcd 13.69ab 13.33abc 14.05a 0.78 
    22:6n-3 7.82abcd 4.61f 6.03cdef 5.76def 4.41f 5.63def 5.00ef 5.85cdef 6.31bcdef 7.48abcde 4.75f 6.43bcdef 9.31a 6.50bcdef 8.71ab 8.33abc 0.44 
SFA2 137.1a 106.6ab 122.2ab 105.4ab 110.1ab 108.6ab 103.9ab 97.49b 125.1ab 116.6ab 96.87b 111.7ab 120.5ab 112.7ab 127.9ab 134.7a 6.1 
MUFA3 88.44 77.31 90.55 74.00 77.74 74.21 71.44 68.16 95.95 82.33 70.94 79.93 71.48 84.39 92.74 79.25 7.03 
PUFA4 169.3ab 129.0ab 161.8ab 130.0ab 135.7ab 134.6ab 120.9b 119.6b 162.1ab 140.9ab 124.3ab 147.4ab 164.5ab 149.3ab 173.6a 163.9ab 8.81 
Total n-3 25.41cd 21.51d 31.23bcd 28.00bcd 30.13bcd 29.30bcd 28.55bcd 29.53bcd 23.09d 25.42cd 27.47bcd 36.65abcd 37.32abcd 41.43abc 48.08a 41.92ab 2.90 
Total n-6 143.8a 107.5bcde 130.5abc 102.0cde 105.5bcde 105.3bcde 92.34de 90.06e 139.1ab 115.4abcde 96.86cde 110.8abcde 127.2abcd 107.9bcde 125.5abcd 122.0abcde 6.2 
n-6:n-3 5.66a 4.99b 4.18c 3.65d 3.50de 3.60d 3.24def 3.05efg 6.02a 4.54bc 3.53de 3.02efg 3.40def 2.64g 2.64g 2.91fg 0.09 
 Low (10% flaxseed) High (17% flaxseed) 
Item 0 d 4 d 8 d 12 d 16 d 20 d 24 d 35 d 0 d 4 d 8 d 12 d 16 d 20 d 24 d 35 d SE 
a–hMeans within a row with no common superscript are significantly different (P < 0.05). 
1ND = not detected. 
2SFA = saturated fatty acids. 
3MUFA = monounsaturated fatty acids. 
4PUFA = polyunsaturated fatty acids. 
Fatty acids 
    14:0 ND1 ND ND ND ND 0.51bc 0.35bc 0.20bc 1.08ab 1.13ab 1.13ab 1.05abc 2.09a 1.13ab 1.01bc 0.92bc 0.19 
    16:0 69.25 59.12 66.65 61.13 64.19 60.55 57.97 53.75 63.65 61.91 51.13 57.31 52.49 62.73 63.05 61.98 3.68 
    16:1n-7 2.81 2.89 2.08 2.11 2.68 2.32 2.80 2.08 2.68 1.44 2.29 2.21 1.17 3.05 1.30 1.46 0.37 
    18:0 67.87ab 47.44cd 55.52abcd 44.29d 45.86d 47.57cd 45.61d 43.54d 60.33abcd 53.54bcd 44.62d 53.34bcd 65.93ab 48.86cd 63.83abc 71.84a 2.97 
    18:1n-7 16.19ab 12.44bcd 13.47abc 10.94cd 10.86cd 10.24cd 9.53d 10.33cd 16.48a 13.49abc 10.03cd 12.09cd 12.25cd 10.62cd 12.02cd 11.67cd 0.67 
    18:1n-9 69.44 61.98 75.00 60.96 64.20 61.64 59.12 55.75 76.80 67.40 58.62 65.63 58.06 70.72 79.42 66.12 6.29 
    18:2n-6 99.47ab 77.34abc 95.97abc 74.65abc 78.87abc 81.54abc 69.26c 71.47bc 101.20a 81.76abc 71.03bc 82.24abc 97.49abc 84.05abc 99.68ab 93.11abc 5.18 
    18:3n-3 4.68b 5.49ab 11.11ab 7.67ab 8.25ab 8.30ab 7.21ab 7.20ab 5.56ab 6.08ab 8.60ab 12.12ab 9.19ab 15.35ab 18.67a 11.92ab 2.37 
    20:2n-6 2.35a ND 2.09ab 1.50abc 1.53abc 1.12bc 0.45cd ND 1.63ab 1.79ab 1.36abc 1.15bc 1.37abc 1.29abc 1.40abc 1.41abc 0.20 
    20:3n-6 2.74a 2.42ab 2.59ab 2.35ab 2.56ab 2.01ab 2.27ab 1.73b 2.02 2.05 2.14 2.37 2.24 2.49 2.29 2.26 0.17 
    20:4n-6 33.78a 24.00bcd 26.48bc 20.55cde 20.07cde 19.15de 18.38de 15.48e 30.58ab 26.59abc 20.35cde 22.88cd 24.58bcd 18.73de 20.85cde 23.79bcd 1.28 
    20:5n-3 2.35gh 2.89fgh 3.66efgh 3.86defgh 4.95cdef 4.45cdefg 5.24bcde 4.89cdef 2.20h 2.33gh 4.01cdefgh 5.59abcde 6.14abc 5.88abcd 7.37ab 7.62a 0.39 
    22:4n-6 5.51a 3.72b 3.41bc 2.96bcd 2.51cde 1.47ef 1.98def 1.38ef 3.59bc 3.26bc 1.97def 2.11def 1.47ef 1.34f 1.29f 1.38ef 0.20 
    22:5n-3 10.56abcd 8.52d 10.44abcd 10.72abcd 12.51abcd 10.91abcd 11.09abcd 11.59abcd 9.02cd 9.53bcd 10.10abcd 12.52abcd 12.68abcd 13.69ab 13.33abc 14.05a 0.78 
    22:6n-3 7.82abcd 4.61f 6.03cdef 5.76def 4.41f 5.63def 5.00ef 5.85cdef 6.31bcdef 7.48abcde 4.75f 6.43bcdef 9.31a 6.50bcdef 8.71ab 8.33abc 0.44 
SFA2 137.1a 106.6ab 122.2ab 105.4ab 110.1ab 108.6ab 103.9ab 97.49b 125.1ab 116.6ab 96.87b 111.7ab 120.5ab 112.7ab 127.9ab 134.7a 6.1 
MUFA3 88.44 77.31 90.55 74.00 77.74 74.21 71.44 68.16 95.95 82.33 70.94 79.93 71.48 84.39 92.74 79.25 7.03 
PUFA4 169.3ab 129.0ab 161.8ab 130.0ab 135.7ab 134.6ab 120.9b 119.6b 162.1ab 140.9ab 124.3ab 147.4ab 164.5ab 149.3ab 173.6a 163.9ab 8.81 
Total n-3 25.41cd 21.51d 31.23bcd 28.00bcd 30.13bcd 29.30bcd 28.55bcd 29.53bcd 23.09d 25.42cd 27.47bcd 36.65abcd 37.32abcd 41.43abc 48.08a 41.92ab 2.90 
Total n-6 143.8a 107.5bcde 130.5abc 102.0cde 105.5bcde 105.3bcde 92.34de 90.06e 139.1ab 115.4abcde 96.86cde 110.8abcde 127.2abcd 107.9bcde 125.5abcd 122.0abcde 6.2 
n-6:n-3 5.66a 4.99b 4.18c 3.65d 3.50de 3.60d 3.24def 3.05efg 6.02a 4.54bc 3.53de 3.02efg 3.40def 2.64g 2.64g 2.91fg 0.09 
Table 6

Fatty acid profile (mg of fatty acids/100 g of meat) in breast meat triacylglycerols

 Low (10% flaxseed) High (17% flaxseed)  
Item 0 d 4 d 8 d 12 d 16 d 20 d 24 d 35 d 0 d 4 d 8 d 12 d 16 d 20 d 24 d 35 d SE 
a–iMeans within a row with no common superscript are significantly different (P < 0.05). 
1ND = not detected. 
2SFA = saturated fatty acids. 
3MUFA = monounsaturated fatty acids. 
4PUFA = polyunsaturated fatty acids. 
Fatty acids 
    14:0 5.47ab 4.93ab 3.70b 4.12b 7.42ab 5.61ab 6.16ab 9.17a 4.69ab 5.72ab 6.23ab 5.12ab 5.11ab 4.83ab 4.39b 5.68ab 0.83 
    16:0 239.4ab 183.8b 148.4b 167.8b 296.4ab 218.3ab 239.1ab 403.5a 184.3b 250.3ab 259.5ab 192.0b 185.5b 181.9b 161.9b 233.6ab 34.5 
    16:1n-7 45.27b 30.41b 26.54b 30.61b 59.28b 58.54b 47.64b 101.0a 28.74 41.92 46.47 34.92 28.65 32.02 27.93 41.76 7.37 
    18:0 62.12ab 51.51ab 41.32b 45.51ab 80.71ab 56.59ab 70.71ab 93.92a 56.67 81.54 73.95 56.77 60.47 56.19 50.38 74.19 8.99 
    18:1n-7 44.59 37.26 30.67 32.54 57.28 36.81 39.29 63.78 41.59 53.50 49.82 32.57 36.7 40.15 30.18 41.37 6.11 
    18:1n-9 617.5ab 495.5ab 419.0b 437.4ab 797.5ab 526.3ab 566.5ab 920.5a 551.8 757.6 707.0 477.8 531.9 575.1 446.3 632.9 87.0 
    18:2n-6 361.8 337.5 268.2 273.0 499.5 270.9 354.5 508.0 374.2 478.9 449.7 306.6 378.1 418.6 316.8 407.2 51.6 
    18:3n-3 70.68f 97.07ef 91.93ef 119.4def 242.8abcd 148.5cdef 175.1bcdef 295.4ab 76.86f 140.6cdef 216.4abcde 199.7abcdef 241.6abcd 302.2ab 258.0abc 334.4a 24.2 
    18:3n-6 1.85 1.50 1.13 1.32 2.24 1.40 1.72 2.28 1.78 2.55 2.12 1.52 1.66 1.69 1.43 1.84 0.26 
    20:0 1.29abcd 1.12bcd 0.97d 1.05bcd ND1 ND 1.42abcd 1.68ab 1.37abcd 1.86a 1.60abc 0.98cd 1.33abcd 1.26abcd 1.12bcd 1.46abcd 0.11 
    20:2n-6 2.40 2.37 1.82 1.86 2.65 2.01 2.37 3.11 2.46 2.74 2.75 1.99 2.06 2.37 1.71 2.16 0.28 
    20:3n-6 1.27 ND ND ND 1.67 1.30 1.40 1.92 1.28 1.62 1.66 1.29 1.47 1.37 1.22 1.90 0.15 
    20:4n-6 2.18 2.01 2.19 2.01 2.94 2.10 2.79 2.91 3.34abc 4.49a 3.33abc 2.03c 2.80bc 2.57bc 2.22bc 3.71ab 0.27 
    20:5n-3 0.44f 0.68ef 1.04def 1.27cdef 2.17bcd 1.90bcde 2.02bcde 3.01b 0.75ef 1.40cdef 2.51bc 2.15bcd 2.78b 2.88b 2.91b 4.61a 0.24 
    22:1 0.99d 1.02d 1.00d 1.21cd 2.12abc 1.63cd 1.97abcd 2.74a 1.16ef 1.47def 1.93cd 1.75cd 1.96cd 2.05c 2.05c 2.61ab 0.17 
    22:5n-3 1.12e 1.14e 1.27de 1.65cde 2.74bcde 2.52bcde 2.89bcd 3.79ab 1.40de 2.29bcde 3.30bc 2.59bcde 3.38b 3.22bc 2.86bcd 5.37a 0.30 
    22:6n-3 ND ND ND ND ND ND ND 1.05b ND 1.05b ND ND ND 1.00b 0.96b 2.07a 0.05 
SFA2 308.3ab 241.4b 194.4b 218.5b 384.5ab 280.5ab 317.4ab 508.3a 247.1 339.4 341.3 254.9 252.4 244.2 217.8 314.9 44.3 
MUFA3 708.3ab 564.2ab 477.2b 501.8b 916.2ab 623.3ab 655.4ab 1,088a 623.3 854.5 805.3 547.1 599.2 649.3 506.4 718.7 100.4 
PUFA4 441.7ab 442.3ab 367.5b 400.6ab 756.7ab 430.6ab 542.8ab 821.5a 462.0 635.7 681.7 517.9 633.8 735.9 588.0 763.2 76.4 
Total n-3 72.24f 98.89ef 94.24ef 122.3def 247.7abcd 153.0cdef 180.0bcdef 303.3ab 79.00d 145.4cd 222.2abc 204.5bcd 247.8abc 309.3ab 264.7abc 346.4a 24.7 
Total n-6 369.5 343.4 273.3 278.3 509.0 277.7 362.7 518.3 383.0 490.3 459.5 313.4 386.1 426.6 323.3 416.8 52.5 
n-6:n-3 5.12a 3.48b 2.92c 2.28d 2.06def 1.81efg 2.02def 1.71fgh 4.83a 3.37b 2.07de 1.53ghi 1.56ghi 1.38hi 1.22i 1.20i 0.06 
 Low (10% flaxseed) High (17% flaxseed)  
Item 0 d 4 d 8 d 12 d 16 d 20 d 24 d 35 d 0 d 4 d 8 d 12 d 16 d 20 d 24 d 35 d SE 
a–iMeans within a row with no common superscript are significantly different (P < 0.05). 
1ND = not detected. 
2SFA = saturated fatty acids. 
3MUFA = monounsaturated fatty acids. 
4PUFA = polyunsaturated fatty acids. 
Fatty acids 
    14:0 5.47ab 4.93ab 3.70b 4.12b 7.42ab 5.61ab 6.16ab 9.17a 4.69ab 5.72ab 6.23ab 5.12ab 5.11ab 4.83ab 4.39b 5.68ab 0.83 
    16:0 239.4ab 183.8b 148.4b 167.8b 296.4ab 218.3ab 239.1ab 403.5a 184.3b 250.3ab 259.5ab 192.0b 185.5b 181.9b 161.9b 233.6ab 34.5 
    16:1n-7 45.27b 30.41b 26.54b 30.61b 59.28b 58.54b 47.64b 101.0a 28.74 41.92 46.47 34.92 28.65 32.02 27.93 41.76 7.37 
    18:0 62.12ab 51.51ab 41.32b 45.51ab 80.71ab 56.59ab 70.71ab 93.92a 56.67 81.54 73.95 56.77 60.47 56.19 50.38 74.19 8.99 
    18:1n-7 44.59 37.26 30.67 32.54 57.28 36.81 39.29 63.78 41.59 53.50 49.82 32.57 36.7 40.15 30.18 41.37 6.11 
    18:1n-9 617.5ab 495.5ab 419.0b 437.4ab 797.5ab 526.3ab 566.5ab 920.5a 551.8 757.6 707.0 477.8 531.9 575.1 446.3 632.9 87.0 
    18:2n-6 361.8 337.5 268.2 273.0 499.5 270.9 354.5 508.0 374.2 478.9 449.7 306.6 378.1 418.6 316.8 407.2 51.6 
    18:3n-3 70.68f 97.07ef 91.93ef 119.4def 242.8abcd 148.5cdef 175.1bcdef 295.4ab 76.86f 140.6cdef 216.4abcde 199.7abcdef 241.6abcd 302.2ab 258.0abc 334.4a 24.2 
    18:3n-6 1.85 1.50 1.13 1.32 2.24 1.40 1.72 2.28 1.78 2.55 2.12 1.52 1.66 1.69 1.43 1.84 0.26 
    20:0 1.29abcd 1.12bcd 0.97d 1.05bcd ND1 ND 1.42abcd 1.68ab 1.37abcd 1.86a 1.60abc 0.98cd 1.33abcd 1.26abcd 1.12bcd 1.46abcd 0.11 
    20:2n-6 2.40 2.37 1.82 1.86 2.65 2.01 2.37 3.11 2.46 2.74 2.75 1.99 2.06 2.37 1.71 2.16 0.28 
    20:3n-6 1.27 ND ND ND 1.67 1.30 1.40 1.92 1.28 1.62 1.66 1.29 1.47 1.37 1.22 1.90 0.15 
    20:4n-6 2.18 2.01 2.19 2.01 2.94 2.10 2.79 2.91 3.34abc 4.49a 3.33abc 2.03c 2.80bc 2.57bc 2.22bc 3.71ab 0.27 
    20:5n-3 0.44f 0.68ef 1.04def 1.27cdef 2.17bcd 1.90bcde 2.02bcde 3.01b 0.75ef 1.40cdef 2.51bc 2.15bcd 2.78b 2.88b 2.91b 4.61a 0.24 
    22:1 0.99d 1.02d 1.00d 1.21cd 2.12abc 1.63cd 1.97abcd 2.74a 1.16ef 1.47def 1.93cd 1.75cd 1.96cd 2.05c 2.05c 2.61ab 0.17 
    22:5n-3 1.12e 1.14e 1.27de 1.65cde 2.74bcde 2.52bcde 2.89bcd 3.79ab 1.40de 2.29bcde 3.30bc 2.59bcde 3.38b 3.22bc 2.86bcd 5.37a 0.30 
    22:6n-3 ND ND ND ND ND ND ND 1.05b ND 1.05b ND ND ND 1.00b 0.96b 2.07a 0.05 
SFA2 308.3ab 241.4b 194.4b 218.5b 384.5ab 280.5ab 317.4ab 508.3a 247.1 339.4 341.3 254.9 252.4 244.2 217.8 314.9 44.3 
MUFA3 708.3ab 564.2ab 477.2b 501.8b 916.2ab 623.3ab 655.4ab 1,088a 623.3 854.5 805.3 547.1 599.2 649.3 506.4 718.7 100.4 
PUFA4 441.7ab 442.3ab 367.5b 400.6ab 756.7ab 430.6ab 542.8ab 821.5a 462.0 635.7 681.7 517.9 633.8 735.9 588.0 763.2 76.4 
Total n-3 72.24f 98.89ef 94.24ef 122.3def 247.7abcd 153.0cdef 180.0bcdef 303.3ab 79.00d 145.4cd 222.2abc 204.5bcd 247.8abc 309.3ab 264.7abc 346.4a 24.7 
Total n-6 369.5 343.4 273.3 278.3 509.0 277.7 362.7 518.3 383.0 490.3 459.5 313.4 386.1 426.6 323.3 416.8 52.5 
n-6:n-3 5.12a 3.48b 2.92c 2.28d 2.06def 1.81efg 2.02def 1.71fgh 4.83a 3.37b 2.07de 1.53ghi 1.56ghi 1.38hi 1.22i 1.20i 0.06 
Table 7

Fatty acid profile (mg of fatty acids/100 g of meat) in thigh meat triacylglycerols (low supplementation)1

 Low (10% flaxseed)  
Item 0 d 4 d 8 d 12 d 16 d 20 d 24 d 35 d SE 
a–iMeans within a row with no common superscript are significantly different (P < 0.05). 
1Because of space limitations, data on thigh meat triacylglycerols were divided into 2 tables: Table 7 for low supplementation and Table 8 for high supplementation with flaxseed. 
2ND = not detected. 
3SFA = saturated fatty acids. 
4MUFA = monounsaturated fatty acids. 
5PUFA = polyunsaturated fatty acids. 
Fatty acids 
    14:0 14.49bcde 15.49bc 11.72cde 13.52bcde 15.06bcd 17.92ab 20.56a 21.66a 0.86 
    16:0 588.7cd 604.7bcd 441.2d 531.8cd 594.5cd 749.2abc 818.2ab 932.9a 39.1 
    16:1n-7 165.3bc 149.2bcd 75.37fg 105.3cdefg 129.9bcdef 176.9b 237.8a 260.9a 10.6 
    18:0 91.30d 110.3cd 123.4abcd 130.7abcd 137.8abcd 174.0ab 166.1abc 180.6a 10.7 
    18:1n-7 111.7abc 105.7bc 99.94bc 108.3bc 99.33bc 123.8ab 117.1abc 145.7a 6.56 
    18:1n-9 1,548ab 1,440b 1,394b 1,498b 1,405b 1,778ab 1,748ab 2,078a 94 
    18:2n-6 977.5 956.6 1,027 1,083 995.3 1,129 947.8 1,198 58.3 
    18:3n-3 195.0h 274.1gh 384.9fg 480.7ef 533.8ef 631.1cde 552.7def 776.6abc 33.1 
    18:3n-6 5.01ab 4.56ab 4.38ab 4.49ab 4.10ab 5.43a 5.04ab 4.92ab 0.28 
    20:0 2.54abc 2.21abc 2.47abc 2.48abc 2.23abc 3.08a 2.38abc 2.89ab 0.21 
    20:2n-6 5.39abc 4.98abc 5.63ab 5.25abc 4.94abc 6.42a 4.23abc 5.46abc 0.40 
    20:3n-6 2.44c 2.47c 2.95abc 3.14abc 3.48abc 3.32abc 3.15abc 3.70ab 0.21 
    20:4n-6 4.81de 4.50e 7.01abcde 7.16abcde 5.76cde 6.89abcde 5.66cde 5.50cde 0.50 
    20:5n-3 1.17h 2.11gh 3.66fg 4.77ef 5.31ef 5.34ef 5.84de 6.17cde 0.33 
    22:5n-3 2.11ef 2.23ef 4.38cd 5.12bcd 6.24bc 5.92bcd 5.35bcd 6.12bc 0.35 
    22:6n-3 ND2 ND 1.50cde 1.65bcd 1.10cde 2.34abcd 1.65bcd 2.08abcd 0.26 
SFA3 697.0cd 732.6bcd 578.8d 678.4cd 749.6bcd 944.1abc 1,007ab 1,138a 49.6 
MUFA4 1,825bc 1,695bc 1,569bc 1,711bc 1,634bc 2,078ab 2,103ab 2,485a 109 
PUFA5 1,193e 1,252de 1,442bcde 1,595abcde 1,561abcde 1,796abc 1,531abcde 2,008a 92 
Total n-3 198.3i 278.4ghi 394.5fgh 492.2ef 546.4ef 644.7cde 565.5def 791.0abc 34.0 
Total n-6 990.1 968.6 1,043 1,098 1,009 1,146 960.8 1,212 59.3 
n-6:n-3 4.99a 3.48b 2.64c 2.23d 1.85e 1.78ef 1.70fg 1.53g 0.02 
 Low (10% flaxseed)  
Item 0 d 4 d 8 d 12 d 16 d 20 d 24 d 35 d SE 
a–iMeans within a row with no common superscript are significantly different (P < 0.05). 
1Because of space limitations, data on thigh meat triacylglycerols were divided into 2 tables: Table 7 for low supplementation and Table 8 for high supplementation with flaxseed. 
2ND = not detected. 
3SFA = saturated fatty acids. 
4MUFA = monounsaturated fatty acids. 
5PUFA = polyunsaturated fatty acids. 
Fatty acids 
    14:0 14.49bcde 15.49bc 11.72cde 13.52bcde 15.06bcd 17.92ab 20.56a 21.66a 0.86 
    16:0 588.7cd 604.7bcd 441.2d 531.8cd 594.5cd 749.2abc 818.2ab 932.9a 39.1 
    16:1n-7 165.3bc 149.2bcd 75.37fg 105.3cdefg 129.9bcdef 176.9b 237.8a 260.9a 10.6 
    18:0 91.30d 110.3cd 123.4abcd 130.7abcd 137.8abcd 174.0ab 166.1abc 180.6a 10.7 
    18:1n-7 111.7abc 105.7bc 99.94bc 108.3bc 99.33bc 123.8ab 117.1abc 145.7a 6.56 
    18:1n-9 1,548ab 1,440b 1,394b 1,498b 1,405b 1,778ab 1,748ab 2,078a 94 
    18:2n-6 977.5 956.6 1,027 1,083 995.3 1,129 947.8 1,198 58.3 
    18:3n-3 195.0h 274.1gh 384.9fg 480.7ef 533.8ef 631.1cde 552.7def 776.6abc 33.1 
    18:3n-6 5.01ab 4.56ab 4.38ab 4.49ab 4.10ab 5.43a 5.04ab 4.92ab 0.28 
    20:0 2.54abc 2.21abc 2.47abc 2.48abc 2.23abc 3.08a 2.38abc 2.89ab 0.21 
    20:2n-6 5.39abc 4.98abc 5.63ab 5.25abc 4.94abc 6.42a 4.23abc 5.46abc 0.40 
    20:3n-6 2.44c 2.47c 2.95abc 3.14abc 3.48abc 3.32abc 3.15abc 3.70ab 0.21 
    20:4n-6 4.81de 4.50e 7.01abcde 7.16abcde 5.76cde 6.89abcde 5.66cde 5.50cde 0.50 
    20:5n-3 1.17h 2.11gh 3.66fg 4.77ef 5.31ef 5.34ef 5.84de 6.17cde 0.33 
    22:5n-3 2.11ef 2.23ef 4.38cd 5.12bcd 6.24bc 5.92bcd 5.35bcd 6.12bc 0.35 
    22:6n-3 ND2 ND 1.50cde 1.65bcd 1.10cde 2.34abcd 1.65bcd 2.08abcd 0.26 
SFA3 697.0cd 732.6bcd 578.8d 678.4cd 749.6bcd 944.1abc 1,007ab 1,138a 49.6 
MUFA4 1,825bc 1,695bc 1,569bc 1,711bc 1,634bc 2,078ab 2,103ab 2,485a 109 
PUFA5 1,193e 1,252de 1,442bcde 1,595abcde 1,561abcde 1,796abc 1,531abcde 2,008a 92 
Total n-3 198.3i 278.4ghi 394.5fgh 492.2ef 546.4ef 644.7cde 565.5def 791.0abc 34.0 
Total n-6 990.1 968.6 1,043 1,098 1,009 1,146 960.8 1,212 59.3 
n-6:n-3 4.99a 3.48b 2.64c 2.23d 1.85e 1.78ef 1.70fg 1.53g 0.02 
Table 8

Fatty acid profile (mg of fatty acids/100 g of meat) in thigh meat triacylglycerols (high supplementation)1

 High (17% flaxseed)  
Item 0 d 4 d 8 d 12 d 16 d 20 d 24 d 35 d SE 
a–nMeans within a row with no common superscript are significantly different (P < 0.05). 
1Because of space limitations, data on thigh meat triacylglycerols were divided into 2 tables: Table 7 for low supplementation and Table 8 for high supplementation with flaxseed. 
2ND = not detected. 
3SFA = saturated fatty acids. 
4MUFA = monounsaturated fatty acids. 
5PUFA = polyunsaturated fatty acids. 
Fatty acids 
    14:0 13.50bcde 11.21cde 15.61bc 13.25bcde 9.678e 10.31de 13.18bcde 14.00bcde 0.86 
    16:0 518.8d 428.6d 601.7bcd 501.8d 387.3d 459.0d 535.5cd 567.4cd 39.1 
    16:1n-7 114.4cdefg 67.05g 137.1bcde 109.4cdefg 79.83efg 103.2defg 131.7bcdef 117.9bcdefg 10.6 
    18:0 119.1bcd 117.2bcd 136.1abcd 121.2abcd 101.0d 110.0cd 128.4abcd 151.2abcd 10.7 
    18:1n-7 112.6abc 109.5abc 113.9abc 108.1bc 85.81c 89.80bc 92.78bc 98.02bc 6.56 
    18:1n-9 1,486b 1,463b 1,666ab 1,566ab 1,258b 1,331b 1,461b 1,518b 94 
    18:2n-6 1,064 1,153 1,154 1,194 990.0 938.5 973.6 1,054 58.3 
    18:3n-3 255.0gh 402.8fg 561.7def 733.7bcd 725.5bcd 730.9bcd 819.6ab 935.0a 33.1 
    18:3n-6 4.72ab 4.92ab 5.084ab 5.35ab 4.27ab 4.77ab 3.82b 4.63ab 0.28 
    20:0 ND2 ND ND ND ND 1.46c 1.10abc 1.86bc 0.21 
    20:2n-6 5.50ab 5.87ab 4.39abc 5.08abc 3.89bc 3.20c 3.18c 3.76bc 0.40 
    20:3n-6 2.47c 2.64bc 2.81abc 3.99a 2.95abc 2.71bc 3.44abc 3.95a 0.21 
    20:4n-6 6.33bcde 9.52a 5.23cde 7.43abcd 7.87abc 5.02de 7.33abcde 8.62ab 0.50 
    20:5n-3 1.67h 3.57fg 4.52ef 7.64bcd 8.02bc 6.08de 9.27b 11.16a 0.33 
    22:5n-3 1.91f 3.99de 4.06de 6.64b 6.47b 5.07bcd 6.85b 9.47a 0.35 
    22:6n-3 ND 1.29cde ND 0.93de 2.48abc 2.34abcd 3.01ab 3.29a 0.26 
SFA3 651.4d 557.0d 753.4bcd 636.3d 498.0d 580.8d 679.1cd 734.4bcd 49.6 
MUFA4 1,714bc 1,640bc 1,917abc 1,783bc 1,424c 1,524bc 1,685bc 1,734bc 109 
PUFA5 1,341cde 1,587abcde 1,742abcd 1,965ab 1,752abcd 1,699abcde 1,830abc 2,034a 92 
Total n-3 258.6hi 411.6fg 570.3def 748.9bcd 742.5bcd 744.4bcd 838.7ab 959.0a 34.0 
Total n-6 1,078 1,171 1,166 1,210 1,005 949.4 987.5 1,071 59.3 
n-6:n-3 4.17b 2.84d 2.05g 1.62jk 1.35l 1.28lm 1.18mn 1.12n 0.02 
 High (17% flaxseed)  
Item 0 d 4 d 8 d 12 d 16 d 20 d 24 d 35 d SE 
a–nMeans within a row with no common superscript are significantly different (P < 0.05). 
1Because of space limitations, data on thigh meat triacylglycerols were divided into 2 tables: Table 7 for low supplementation and Table 8 for high supplementation with flaxseed. 
2ND = not detected. 
3SFA = saturated fatty acids. 
4MUFA = monounsaturated fatty acids. 
5PUFA = polyunsaturated fatty acids. 
Fatty acids 
    14:0 13.50bcde 11.21cde 15.61bc 13.25bcde 9.678e 10.31de 13.18bcde 14.00bcde 0.86 
    16:0 518.8d 428.6d 601.7bcd 501.8d 387.3d 459.0d 535.5cd 567.4cd 39.1 
    16:1n-7 114.4cdefg 67.05g 137.1bcde 109.4cdefg 79.83efg 103.2defg 131.7bcdef 117.9bcdefg 10.6 
    18:0 119.1bcd 117.2bcd 136.1abcd 121.2abcd 101.0d 110.0cd 128.4abcd 151.2abcd 10.7 
    18:1n-7 112.6abc 109.5abc 113.9abc 108.1bc 85.81c 89.80bc 92.78bc 98.02bc 6.56 
    18:1n-9 1,486b 1,463b 1,666ab 1,566ab 1,258b 1,331b 1,461b 1,518b 94 
    18:2n-6 1,064 1,153 1,154 1,194 990.0 938.5 973.6 1,054 58.3 
    18:3n-3 255.0gh 402.8fg 561.7def 733.7bcd 725.5bcd 730.9bcd 819.6ab 935.0a 33.1 
    18:3n-6 4.72ab 4.92ab 5.084ab 5.35ab 4.27ab 4.77ab 3.82b 4.63ab 0.28 
    20:0 ND2 ND ND ND ND 1.46c 1.10abc 1.86bc 0.21 
    20:2n-6 5.50ab 5.87ab 4.39abc 5.08abc 3.89bc 3.20c 3.18c 3.76bc 0.40 
    20:3n-6 2.47c 2.64bc 2.81abc 3.99a 2.95abc 2.71bc 3.44abc 3.95a 0.21 
    20:4n-6 6.33bcde 9.52a 5.23cde 7.43abcd 7.87abc 5.02de 7.33abcde 8.62ab 0.50 
    20:5n-3 1.67h 3.57fg 4.52ef 7.64bcd 8.02bc 6.08de 9.27b 11.16a 0.33 
    22:5n-3 1.91f 3.99de 4.06de 6.64b 6.47b 5.07bcd 6.85b 9.47a 0.35 
    22:6n-3 ND 1.29cde ND 0.93de 2.48abc 2.34abcd 3.01ab 3.29a 0.26 
SFA3 651.4d 557.0d 753.4bcd 636.3d 498.0d 580.8d 679.1cd 734.4bcd 49.6 
MUFA4 1,714bc 1,640bc 1,917abc 1,783bc 1,424c 1,524bc 1,685bc 1,734bc 109 
PUFA5 1,341cde 1,587abcde 1,742abcd 1,965ab 1,752abcd 1,699abcde 1,830abc 2,034a 92 
Total n-3 258.6hi 411.6fg 570.3def 748.9bcd 742.5bcd 744.4bcd 838.7ab 959.0a 34.0 
Total n-6 1,078 1,171 1,166 1,210 1,005 949.4 987.5 1,071 59.3 
n-6:n-3 4.17b 2.84d 2.05g 1.62jk 1.35l 1.28lm 1.18mn 1.12n 0.02 
Table 9

Omega-3 polyunsaturated fatty acids (PUFA) detected (mg of fatty acids/100 g of meat) in total lipid tissue of breast meat

Level Duration, d LNA1 (18:3n-3) EPA2 (20:5n-3) DPA3 (22:5n-3) DHA4 (22:6n-3) Total n-3 
a–hMeans within a row with no common superscript are significantly different (P < 0.05). 
1LNA = linolenic acid. 
2EPA = eicosapentaenoic acid. 
3DPA = docosapentaenoic acid. 
4DHA = docosahexaenoic acid. 
Low (10% flaxseed)  178.9b 7.37b 16.31b 8.12b 210.7b 
High (17% flaxseed)  268.5a 9.83a 19.90a 10.68a 308.9a 
    SE  5.157 0.157 0.348 0.253 5.196 
 96.23f 5.00e 14.21d 9.13abc 124.6f 
 141.8ef 5.82de 15.24d 10.49ab 173.3ef 
 175.1de 6.78d 16.74cd 8.82abc 207.4de 
 12 208.2cd 9.54bc 17.11cd 8.27bc 243.2cd 
 16 253.2bc 8.56c 17.24bcd 7.57c 286.6bc 
 20 262.0b 9.80bc 19.49bc 9.35abc 300.7b 
 24 256.9bc 10.16b 20.62b 10.52ab 298.2b 
 35 395.9a 13.14a 24.19a 11.05a 444.3a 
    SE  10.3 0.31 0.70 0.51 10.4 
Low (10% flaxseed) 95.76h 5.52g 14.03ef 7.58de 122.9g 
 111.6gh 5.35g 13.17f 6.92de 137.1fg 
 109.2gh 4.75g 14.80def 9.56bcd 138.3fg 
 12 138.3fgh 6.56efg 14.31def 6.82de 166.0efg 
 16 205.1def 6.25fg 13.24f 5.39e 230.0de 
 20 181.7efg 8.74def 16.19cdef 6.95de 213.6def 
 24 232.6cde 9.70cd 22.31ab 11.86abc 276.4cd 
 35 356.9ab 12.15abc 22.42ab 9.90bcd 401.4b 
High (17% flaxseed) 96.70h 4.50g 14.39def 10.69abcd 126.3g 
 171.9efgh 6.29fg 17.31bcdef 14.05a 209.6def 
 241.0cde 8.81de 18.69bcdef 8.09cde 276.6cd 
 12 278.2bcd 12.53ab 19.90bcd 9.71bcd 320.4bc 
 16 301.2bc 10.86bcd 21.24abc 9.76bcd 343.1bc 
 20 342.4b 10.86bcd 22.80ab 11.74abc 387.8b 
 24 281.3bcd 10.63bcd 18.92bcde 9.18bcde 320.0bc 
 35 434.9a 14.13a 25.95a 12.20ab 487.2a 
    SE  14.6 0.44 0.99 0.72 14.7 
Source of variation  ——— P > F ——— 
    Level  <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 
    Duration  <0.0001 <0.0001 <0.0001 0.0020 <0.0001 
    Level × duration  0.0008 <0.0001 0.0008 <0.0001 0.0004 
Level Duration, d LNA1 (18:3n-3) EPA2 (20:5n-3) DPA3 (22:5n-3) DHA4 (22:6n-3) Total n-3 
a–hMeans within a row with no common superscript are significantly different (P < 0.05). 
1LNA = linolenic acid. 
2EPA = eicosapentaenoic acid. 
3DPA = docosapentaenoic acid. 
4DHA = docosahexaenoic acid. 
Low (10% flaxseed)  178.9b 7.37b 16.31b 8.12b 210.7b 
High (17% flaxseed)  268.5a 9.83a 19.90a 10.68a 308.9a 
    SE  5.157 0.157 0.348 0.253 5.196 
 96.23f 5.00e 14.21d 9.13abc 124.6f 
 141.8ef 5.82de 15.24d 10.49ab 173.3ef 
 175.1de 6.78d 16.74cd 8.82abc 207.4de 
 12 208.2cd 9.54bc 17.11cd 8.27bc 243.2cd 
 16 253.2bc 8.56c 17.24bcd 7.57c 286.6bc 
 20 262.0b 9.80bc 19.49bc 9.35abc 300.7b 
 24 256.9bc 10.16b 20.62b 10.52ab 298.2b 
 35 395.9a 13.14a 24.19a 11.05a 444.3a 
    SE  10.3 0.31 0.70 0.51 10.4 
Low (10% flaxseed) 95.76h 5.52g 14.03ef 7.58de 122.9g 
 111.6gh 5.35g 13.17f 6.92de 137.1fg 
 109.2gh 4.75g 14.80def 9.56bcd 138.3fg 
 12 138.3fgh 6.56efg 14.31def 6.82de 166.0efg 
 16 205.1def 6.25fg 13.24f 5.39e 230.0de 
 20 181.7efg 8.74def 16.19cdef 6.95de 213.6def 
 24 232.6cde 9.70cd 22.31ab 11.86abc 276.4cd 
 35 356.9ab 12.15abc 22.42ab 9.90bcd 401.4b 
High (17% flaxseed) 96.70h 4.50g 14.39def 10.69abcd 126.3g 
 171.9efgh 6.29fg 17.31bcdef 14.05a 209.6def 
 241.0cde 8.81de 18.69bcdef 8.09cde 276.6cd 
 12 278.2bcd 12.53ab 19.90bcd 9.71bcd 320.4bc 
 16 301.2bc 10.86bcd 21.24abc 9.76bcd 343.1bc 
 20 342.4b 10.86bcd 22.80ab 11.74abc 387.8b 
 24 281.3bcd 10.63bcd 18.92bcde 9.18bcde 320.0bc 
 35 434.9a 14.13a 25.95a 12.20ab 487.2a 
    SE  14.6 0.44 0.99 0.72 14.7 
Source of variation  ——— P > F ——— 
    Level  <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 
    Duration  <0.0001 <0.0001 <0.0001 0.0020 <0.0001 
    Level × duration  0.0008 <0.0001 0.0008 <0.0001 0.0004 
Figure 1

Estimation of Δ5-desaturase activity measured as 20:4n-6/20:3n-6 in thigh meat phospholipid with duration of feeding flax-seed.

Figure 1

Estimation of Δ5-desaturase activity measured as 20:4n-6/20:3n-6 in thigh meat phospholipid with duration of feeding flax-seed.

Figure 2

Estimation of desaturase + elongase activity measured as 20:4n-6/18:2n-6 in breast meat phospholipid with duration of feeding flaxseed.

Figure 2

Estimation of desaturase + elongase activity measured as 20:4n-6/18:2n-6 in breast meat phospholipid with duration of feeding flaxseed.

Figure 3

Optimization of duration of feeding a low (10%) or high (17%) level of dietary flaxseed for n-3 enrichment of broiler meat to a level of 300 mg/100 g of broiler chicken breast meat.

Figure 3

Optimization of duration of feeding a low (10%) or high (17%) level of dietary flaxseed for n-3 enrichment of broiler meat to a level of 300 mg/100 g of broiler chicken breast meat.

Funding for this project was provided by the Alberta Livestock Industry Development Fund (Edmonton, Alberta, Canada), Agriculture and Food Council (Nisku, Alberta, Canada), Poultry Industry Council (Guelph, Ontario, Canada), Alberta Agriculture and Rural Development (Edmonton, Alberta, Canada), and Alberta Chicken Producers (Edmonton, Alberta, Canada). Lilydale (Edmonton, Alberta, Canada) provided chicks, and Archer Daniels Midland provided the ground flaxseed (Omegaflax). We thank Graham Plastow (University of Alberta) for the helpful suggestions for the manuscript.

REFERENCES

An
,
B. K.
, C. Banno, Z. S. Xia, K. Tanaka, and S. Ohtani.
1997
. Effects of dietary fat sources on lipid metabolism in growing chicks (Gallus domesticus).
Comp. Biochem. Physiol.
 
116
:
119
–125.
Azain
,
M. J.
2004
. Role of fatty acids in adipocyte growth and development.
J. Anim. Sci.
 
82
:
916
–924.
Betti
,
M.
, B. L. Schneider, W. Wismer, M. J. Zuidhof, V. L. Carney, and R. A. Renema.
2008
. Omega-3 enriched broiler meat: 2. Functional properties, oxidative stability and consumer acceptance.
Poult. Sci.
 
88
:
1085
–1095.
Bezard
,
J.
, J. P. Blond, A. Bernard, and P. Clouet.
1994
. The metabolism and availability of essential fatty acids in animal and human tissues.
Reprod. Nutr. Dev.
 
34
:
539
–568.
Canadian Food Inspection Agency.
2003
. Guide to Food Labelling and Advertising. http://www.inspection.gc.ca/english/fssa/la-beti/guide/ch7be.shtml#7.19 Accessed Apr. 2008.
Christie
,
W. W.
, and G. H. M. Breckenridge.
1989
. Separation of cis-isomers and trans-isomers of unsaturated fatty-acids by high-performance liquid-chromatography in the silver ion mode.
J. Chromatogr. A
 
469
:
261
–269.
Cortinas
,
L.
, A. Barroeta, J. Galobart, and S. K. Jensen.
2004
. Distribution of α-tocopherol stereoisomers in liver and thigh of chickens.
Br. J. Nutr.
 
92
:
295
–301.
Crespo
,
N.
, and E. Esteve-Garcia.
2002
. Nutrient fatty acid deposition in broilers fed different fatty acids profile.
Poult. Sci.
 
81
:
1533
–1542.
Dublecz
,
K.
, A. Bartos, A. Banyai, L. Wagner, L. Pal, and G. Toth.
2004
. The effect of metabolizable energy content of grower and finisher diets on the performance and carcass composition of male and female broiler chicks.
Zootec. Int.
 
2
:
44
–47.
Eaton
,
S. B.
, S. B. Eaton, M. J. Konner, and M. Shostak.
1996
. An evolutionary perspective enhances understanding of human nutritional requirements.
J. Nutr.
 
126
:
1732
–1740.
Emken
,
E. A.
, R. O. Adolf, and R. M. Gulley.
1994
. Dietary linoleic acid influences desaturation and acylation of deuterium-labeled linoleic and linolenic acids in young adult males.
Biochim. Biophys. Acta
 
1213
:
277
–288.
Folch
,
J.
, M. Lees, and G. H. S. Stanley.
1957
. A simple method for the isolation and purification of total lipids from animal tissues.
J. Biol. Chem.
 
226
:
497
–509.
Fritsche
,
K. L.
, N. A. Cassity, and S. C. Huang.
1991
. Effect of dietary fats on the fatty acid composition of serum and immune system in chicken.
Poult. Sci.
 
70
:
1213
–1222.
Gandemer
,
G
.
2002
. Lipids in muscle and adipose tissue, changes during processing and sensory properties of meat products.
Meat Sci.
 
62
:
309
–321.
Garg
,
M. L.
, E. Sebokoba, A. A. Wierzbicki, A. B. R. Thomson, and M. T. Clandin.
1988
. Differential effects of dietary linoleic acid and α-linolenic acid in rat tissue.
Lipids
 
23
:
847
–852.
Gonzalez-Esquerra
,
R.
, and S. Leeson.
2000
. Effects of menhaden oil and flaxseed in broilers on sensory quality and lipid composition of poultry meat.
Br. Poult. Sci.
 
41
:
481
–488.
Gonzalez-Esquerra
,
R.
, and S. Leeson.
2001
. Alternatives for enrichment of eggs and chicken meat with n-3 fatty acids.
Can. J. Anim. Sci.
 
81
:
295
–305.
Hargis
,
P. S.
, and M. E. Van Elswyk.
1993
. Manipulating the fatty acid composition of poultry meat and eggs for the health conscious consumer.
Worlds Poult. Sci. J.
 
49
:
251
–264.
Jonas
,
A.
2002
. Liporotein structure. Pages 483–504 in Biochemistry of Lipids, Lipoproteins and Membranes. 4th ed. D. E. Vance and J. E. Vance, ed. Elsevier, Paris, France.
Komprda
,
T.
, J. Zelenka, E. Fajmonova, M. Fialova, and D. Kladroba.
2005
. Arachidionic acid and long-chain n-3 polyunsaturated fatty acid contents in meat of selected poultry and fish species in relation to dietary fat sources.
J. Agric. Food Chem.
 
53
:
6804
–6812.
Kramer
,
J. M.
, and H. W. Hulan.
1978
. Comparison of procedures to determine free fatty acids in rat heart.
J. Lipid Res.
 
19
:
103
–106.
Kriketos
,
A. D.
, D. A. Pan, J. R. Sutton, J. F. Y. Baur, L. A. Cooney, G. J. Jenkins, and L. H. Storlein.
1995
. Relationships between muscle membrane lipids, fiber type, and enzyme activities in sedentary and exercised rats.
Am. J. Physiol.
 
269
:
1154
–1162.
Kronberg
,
S. L.
, G. Barcelo-Coblijn, J. Shin, K. Lee, and E. J. Murphy.
2006
. Bovine muscle n-3 fatty acid content is increased with flaxseed feeding.
Lipids
 
41
:
1059
–1068.
Leskanich
,
C. O.
, R. C. Noble, and C. A. Morgan.
1993
. Manipulation of the polyunsaturated fatty acid content of pig meat in conformity with dietary guidelines.
Proc. Nutr. Soc.
 
53
:
14A
. (Abstr.)
Lopez-Ferrer
,
S.
, M. D. Baucells, A. C. Barroeta, J. Galobart, and M. A. Grashorn.
2001a
. n-3 enrichment of chicken meat. 2. Use of precursors of long-chain polyunsaturated fatty acids: Linseed oil.
Poult. Sci.
 
80
:
753
–761.
Lopez-Ferrer
,
S.
, M. D. Baucells, A. C. Barroeta, and M. A. Grashorn.
1999
. n-3 enrichment of chicken meat using fish oil: Alternative substitution with rapeseed and linseed oils.
Poult. Sci.
 
78
:
356
–365.
Lopez-Ferrer
,
S.
, M. D. Baucells, A. C. Barroeta, and M. A. Grashorn.
2001b
. n-3 enrichment of chicken meat. 1. Use of very long-chain fatty acids in chicken diets and their influence on meat quality: Fish oil.
Poult. Sci.
 
80
:
741
–752.
Monteiro
,
A. C. G.
, J. Santos-Silva, R. J. B. Bessa, D. R. Navas, and J. P. C. Lemos.
2006
. Fatty acid composition of intramuscular fat of bulls and steers.
Livest. Sci.
 
99
:
13
–19.
Mourot
,
J.
, and D. Hermier.
2001
. Lipids in monogastric animal meat.
Reprod. Nutr. Dev.
 
41
:
109
–118.
Papinaho
,
P. A.
, M. H. Ruusunen, and T. Suuronen.
1996
. Relationship between muscle biochemical and meat quality of early deboned breast meat.
J. Appl. Poult. Res.
 
5
:
126
–133.
Plourde
,
M.
, and S. C. Cunnane.
2007
. Extremely limited synthesis of long chain polyunsaturates in adults: Implication for their dietary essentiality and use as supplement.
Appl. Physiol. Nutr. Metab.
 
32
:
619
–634.
Riley
,
P. A.
, M. Enser, G. R. Nute, and J. D. Wood.
2000
. Effect of dietary linseed on nutritional value and other quality aspects of pig muscle and adipose tissue.
Anim. Sci.
 
71
:
483
–500.
Rymer
,
C.
, and D. I. Givens.
2005
. n-3 fatty acid enrichment of edible tissue of poultry: A review.
Lipids
 
40
:
121
–130.
Sanosaka
,
M.
, T. Minashima, K. Suzuki, K. Watanabe, S. Ohwada, A. Hagino, M. T. Rose, T. Yamaguchi, and H. Aso.
2008
. A combination of octanoate and oleate promotes in vitro differentiation of porcine intramuscular adipocytes.
Comp. Biochem. Physiol.
 
149
:
285
–292.
Schmitz
,
G.
, and J. Ecker.
2008
. The opposing effects of n-3 and n-6 fatty acids.
Prog. Lipid Res.
 
47
:
147
–155.
Scollan
,
N. D.
, J. F. Hocquette, K. Nuernberg, D. Dannenberger, R. I. Richardson, and A. Maloney.
2006
. Innovations in beef production systems that enhance the nutritional and health value of beef lipids and their relationship with meat quality.
Meat Sci.
 
74
:
17
–33.
Shen
,
Y.
, F. Dingyuan, M. Z. Fan, and E. R. Chavez.
2005
. Performance, carcass cut-up and fatty acids deposition in broilers fed different levels of pellet-processed flaxseed.
J. Sci. Food Agric.
 
85
:
2005
–2014.
Siddiqui
,
R. A.
, M. Zerouga, M. Wu, A. Castillo, K. Harvey, G. P. Zaloga, and W. Stillwell.
2005
. Anticancer properties of propofol-docosahexaenoate and propofol-eicosapentaenoate on breast cancer cells.
Breast Cancer Res.
 
7
:
R645
–R654.
Simopoulos
,
A. P.
1997
. Omega-3 fatty acids in the prevention-mangement of cardiovascular disease.
Can. J. Physiol. Pharmacol.
 
75
:
234
–239.
Simopoulos
,
A. P.
2004
. Omega-6/omega essential fatty acid ratio and chronic disease.
Food Rev. Int.
 
20
:
77
–90.
Simopoulos
,
A. P.
2006
. Evolutionary aspects of diet, the omega-6/omega-3 ratio and genetic variation: Nutritional implications for chronic diseases.
Biomed. Pharmacother.
 
60
:
502
–507.
Specht-Overholt
,
S.
, J. R. Romans, M. J. Marchello, R. S. Izard, M. G. Crews, D. M. Simon, W. J. Costello, and P. D. Evenson.
1997
. Fatty acid composition of commercially manufactured omega-3 enriched pork products.
J. Anim. Sci.
 
75
:
2335
–2343.
Storlein
,
T. H.
, D. A. Pan, A. D. Kriketos, J. O’Connor, I. D. Caterson, G. J. Cooney, A. B. Jenkins, and L. A. Baur.
1995
. Skeletal muscle membrane and storage lipids, muscle fibre type and insulin resistance.
Lipids
 
31
:
261S
–265S.
Toms
,
J. D.
, and M. L. Lesperance.
2003
. Piecewise regression: A tool for identifying ecological threshold.
Ecology
 
84
:
2034
–2041.
US Food and Drug Administration.
2004
. FDA Announces Qualified Health Claims for Omega-3 Fatty Acids. http://www.fda.gov/bbs/topics/news/2004/NEW01115.html Accessed Nov. 15, 2007.
Villaverde
,
C.
, M. D. Baucells, L. Cortinas, and A. C. Barroeta.
2006
. Effects of dietary concentration and degree of polyunsaturation of dietary fat on endogenous synthesis and deposition of fatty acids in chickens.
Br. Poult. Sci.
 
47
:
173
–179.
Warnants
,
N.
, M. J. Van Oeckel, and C. V. Boucque.
1999
. Incoporation of dietary fatty acids into pork fat tissues.
J. Anim. Sci.
 
77
:
2478
–2490.
Wood
,
J. V.
, M. Enser, A. V. Fisher, G. R. Nute, P. R. Sheard, R. I. Richardson, S. I. Hughes, and F. M. Whittington.
2008
. Fat deposition, fatty acid composition and meat quality: A review.
Meat Sci.
 
78
:
343
–358.
Zelenka
,
J.
, D. Scheneiderpva, E. Mrkvicova, and P. Dolezal.
2008
. The effect of dietary linseed oil with different fatty acid pattern on the content of fatty acids in chicken meat.
Vet. Med.
 
53
:
77
–85.
Zuidhof
,
M. J.
, M. Betti, D. R. Korver, F. I. L. Hernandez, B. L. Schneider, V. L. Carney, and R. A. Renema.
2009
. Omega-3 enriched broiler meat: 1. Optimization of a production system.
Poult. Sci.
 
88
:
1108
–1120.