Yolk sac fatty acid composition, yolk absorption, embryo development, and chick quality during incubation in eggs from young and old broiler breeders

Abstract

The objective of the present study was to examine the changes in yolk and yolk sac fatty acid composition and also to investigate egg content, yolk absorption, embryo development during incubation, and chick quality at hatch in eggs from 36- and 52-wk-old broiler breeders. The fatty acid profiles of the yolk, the yolk sac of embryos, and the residual yolk sac of chicks were analyzed before incubation, on d 18, and at hatch, respectively. Yolk sac weight, and embryo weight and length were measured on d 18, and chick weight and length were measured at hatch. Egg weight, yolk and albumen weight, yolk percentage, and yolk:albumen ratio increased as breeder age increased, but the albumen percentage decreased. Yolk absorption in absolute value (g) was higher in embryos from the old flock on d 18 and at hatch. Relative yolk absorption was similar between age groups on d 18, whereas it was higher in the young flock at hatch. Breeder age affected the yolk sac weight and was higher in the old flock during incubation. Embryo or chick weight and length, and yolk-free BW were affected by breeder age during incubation. These parameters were higher in the old flock with a difference of 3.7 g, 0.8 cm, and 2.6 g, respectively, on d 18 and 7.4 g, 1.4 cm, and 6.3 g, respectively, at hatch compared with the young flock. The effect of breeder age on fatty acid composition differed significantly by sampling day. Palmitic, stearic, oleic, and linoleic acids were major fatty acids in the fresh yolk, ranging from 13.02 to 29.24%. These were followed by palmitoleic and arachidonic acids ranging from 1.24 to 7.04%, with the remaining fatty acids below 1%. Higher concentrations of myristic, palmitoleic, and oleic acids and lower concentrations of heptadeconoic, stearic, linoleic, and arachidonic acids were found in the residual yolk sac of the young flock than the old flock. The results showed preferentially selective absorption of some fatty acids by the embryo during incubation.

Egg storage and breeder age impact on egg quality and embryo development

“…At day 18 of incubation, Wilson (1991) and Şahan, Ipek, and Sozcu (2014) noted a higher embryo weight (Δ = 3.7 g), length (Δ = 0.8 cm) and yolk-free body weight (YFBM; Δ = 2.6 g) in older flocks (52 weeks) compared to younger flocks (36 weeks). Nangsuay et al (2016) used breeders of 29 and 53 weeks of age.…”

Review on docosahexaenoic acid in poultry and swine nutrition: Consequence of enriched animal products on performance and health characteristics

“…Egg yolk comprises around 30% lipid, the composition of which varies depending on the hen's age, strain and diet ( Grobas et al., 2001 , Şahan et al., 2014 ). Reports indicate that including a source of n-3 PUFA in laying hen diets is an effective way of increasing content of these essential FA in egg yolk ( Hargis and Van Elswyk, 1993 ).…”

Embryonic cholesterol esterification is regulated by a cyclic AMP-dependent pathway in yolk sac membrane-derived endodermal epithelial cells

“…Palmitic acid (PA) and oleic acids (OA) are the two most abundant fatty acids in egg yolk both in Japanese quail and chicken egg yolk. In quail eggs, there is approximately 17% of PA (C16:0) and 27% of OA (C18:1n9c); in chicken eggs, there is approximately 27% of PA and 30% of OA [ 20 , 21 ]. To determine the effects of fatty acids on SOAT1 transcriptions, we treated cells with two long-chain fatty acids which had the greatest concentration in avian yolk.…”