Effects of Different PUFAs Supplementation on Uterine Gene Expression During the Postpartum Periods of Early Lactating Dairy Cows.

Dairy and Meat Production, Sari, Iran The objectives were to determine if a diet enriched in a-linolenic acid (omega-3), or linolenic acid (omega-6) would influence Prostaglandin Cascade in lactating dairy cows. Twenty four high-yielding multiparous Holstein dairy cows with no over clinical illnesses were blocked according to calving date and parity. Cows were assigned randomly to be fed: 1) soybean whole roast (S, n=8), or 2) linseed (L, n=8), or 3) palm oil as a source of saturated fatty acid (C, n=8) from calving until first day 60 postpartum (dpp). At 30 dpp, cows (n= 30) received 2 injections of PGF2a 14 d apart for estrous synchronization. On d 15 of the synchronized estrous cycle (59.3±2.6 DIM), Uterine endometrial biopsies were collected immediately after completion of the oxytocin challenge. We applied real time PCR for measurement genes mRNA abundance of PPARs, COX-2 and PGFS. Real time PCR was executed in triplicate. Initial step contained 10 min at 95°C, and followed by 50 cycles of a two-phase PCR (denaturation at 95°C for 20s; annealing and extension at 60°C for 30 s). Reaction mixtures for real-time PCR included 1 μL cDNA as template, 7.5 SYBRR Green PCR Master Mix (ABI, USA), 1 μL of forward, 1 μL of reverse primers and 4.5 μL double distilled water. We used of 2– ΔΔCt method in this model. Data were analyzed using the MIXED procedure of SAS. Result showed uterine endometrial PPARa and PPAR d genes were found to be differentially (P < 0.05) expressed in the L compared with other group. Mean gene expression for PPAR d increased (P < 0.05) by 3.1-fold in animals fed the high n-3 PUFA diet than the control and omega-6, while expression of mRNA for PPAR a was also nearly 1.3-fold higher (P < 0.05) in animals fed the high PUFA diet versus other groups. Expression of mRNA for COX-2, PGFS, PPAR γ was not differentially expressed between animals fed the omega-3, omega-6 or control diets.