K. Damaziak, J. Riedel, D. Gozdowski, J. Niemiec, A. Siennicka, D. Róg; Productive performance and egg quality of laying hens fed diets supplemented with garlic and onion extracts. J Appl Poult Res 2017 pfx001. doi: 10.3382/japr/pfx001
The study was aimed at evaluating the effect of supplementing a diet for laying hens with onion and garlic extracts on their productive performance and egg quality. Two-hundred-sixteen laying hens were divided into 3 groups: standard diet, diet with a 0.0032% addition of onion extract, and diet with a 0.0032% addition of garlic extract. The egg production rate, egg weight, and feed conversion ratio were monitored within the first 17 wk of the laying period. In wk 6, 8, 10, 12, 14, and 16 of the laying period, eggs were analyzed for: weight, weight to yolk ratio, yolk color, albumen quality, and eggshell quality. In wk 7 and 15 of the laying period, analyses were conducted for: yolk color, consistency, aroma, and taste of boiled eggs. The addition of a garlic extract had a positive effect on the production rate in the initial and peak egg-laying period, and significantly determined the aroma and, in the further stage of the production process, also taste of boiled eggs. Administration of the diet with onion extract to hens caused them to begin the egg-laying period later but laying heavier eggs, with a higher content of egg yolk and better quality of albumen. The analysis of the productive performance of hens and quality of eggs indicates the advisability of applying the extract from garlic in commercial flocks of laying hens. In the future, it seems substantiated to analyze the effect of extract supplementation at the end of the laying period.