A review on yolk sac utilization in poultry

Abstract

During incubation, embryonic growth and development are dependent on nutrients deposited in the egg. The content of the yolk can be transferred to the embryo in 2 ways: directly into the intestine via the yolk stalk or through the highly vascularized yolk sac membrane. It has been suggested that, as a result of genetic selection and improved management, the increase in posthatch growth rate and concurrently the increase in metabolic rate of broiler chickens during the last 50 yr has also increased embryonic metabolism. A higher metabolic rate during incubation would imply a lower residual yolk weight and possibly lower energy reserve for the hatchling. This might affect posthatch development and performance. This review examined scientific publications published between 1930 and 2018 to compare residual yolk weight at hatch, metabolic heat production, and yolk utilization throughout incubation. This review aimed to investigate 1) whether or not residual yolk weight and composition has been changed during the 88-yr period considered and 2) which abiotic and biotic factors affect yolk utilization in poultry during incubation and the early posthatch period. It can be concluded that 1) residual yolk weight and the total solid amount of the residual yolk at hatch seem to be decreased in the recent decades. It cannot be concluded whether the (lack of) differences between old and modern strains are due to genetic selection, changed management and incubation conditions, or moment of sampling (immediately after hatch or at pulling). It is remarkable that with the genetic progress and improved management and incubation conditions over the last 88 yr, effects on yolk utilization efficiency and embryonic metabolic heat production are limited; 2) factors specially affecting residual yolk weight at hatch include egg size and incubation temperature, whereas breeder age has more influence on nutrient composition of the residual yolk.

Centennial Review: The chicken yolk sac is a multifunctional organ

“…Breeder age and egg size affect egg composition (see review by van der Wagt et al., 2020 ). Larger eggs from hens of the same age flock have a greater percentage of albumen than yolk compared with smaller eggs ( Vieira and Moran, 1998 ).…”

“…In addition to this natural degradation of the YS tissue, any disruption in absorption of the YS content may lead to deficiency of necessary nutrients and maternal antibodies that can result in early chick mortality and poor chick quality. For a comprehensive analysis of the effects of broiler breeder, egg size, egg storage, and incubation temperature on yolk utilization, see the recent review by van der Wagt et al. (2020) .…”

Effect of Dietary L-Methionine Supplementation on Growth Performance, Carcass Traits, and Plasma Parameters of Starter Pekin Ducks at Different Dietary Energy Levels

“…The results were in line with our previous studies, which showed that an increase in ADG and a decrease in ADFI and F/G as dietary increased ME levels in the diet of starter [ 21 ] and growing [ 13 , 22 ] Pekin ducks. In addition, as the dietary ME level decreased from 12.52 to 11.54 MJ/kg, we observed that the BW and ADG were significantly decreased starting at the second week ( Figure 1 ), which might be due to the yolk sac in the body of the duckling that provided the nutrients for the first week [ 23 , 24 ]. However, Met deficiency led to poor growth performance starting in the first week ( Figure 2 ), which suggested that the growth response to dietary Met concentration for ducklings of one week of age might be greater than that to dietary ME concentration.…”

Prediction and Effect of Maternal Marginal Zinc Deficiency on Development, Redox Status, and Gene Expression Related to Oxidation and Apoptosis of Embryos

“…Development and growth of poultry embryos are dependent upon the nutrient deposits in the eggs [19]. The yolk sac provides the chicken embryo with essential minerals nutrients for embryonic growth [20,21].…”