In avians, yolk synthesis is regulated by incorporation of portomicrons from the diet, transport of lipoproteins from the liver, and release of lipids from adipose tissue; however, the extent to which lipolysis in adipose tissue contributes to yolk synthesis and egg production has yet to be elucidated. G0/G1 switch gene 2 (G0S2) is known to bind and inhibit adipose triglyceride lipase (ATGL), t...

The relationship of albumen height (AH) to the compositions of yolks and embryos in hatching eggs from a young (30 wk of age) broiler breeder flock was evaluated during incubation. On Day 2 of incubation, egg weight, yolk weight, and yolk moisture, lipid, and fatty acid contents were determined in eggs from broiler breeders previously identified as laying eggs of either low or high AH. In addit...

Twenty 35-wk-old chickens, including 10 Single Comb White Leghorn (SCWL) and 10 Rhode Island Red (RIR) hens, were used to examine the effects of egg and yolk weights on egg yolk antibody (IgY) production in the two strains of chickens immunized with BSA. The SCWL chickens had a greater (P < 0.01) percentage hen-day production and greater egg and yolk weights than did the RIR chickens. However, ...

Animal origin egg yolk extender has been associated with microbial contamination and interference with microscopic examination. Therefore, replacement of such extender with plant origin compound is inevitable without compromising the desired qualities of an ideal extender. In the current experiment, we compared the effect of soy-based extender (25% and 50%) of five adult Holstein-Friesian bulls...

The aim of this study was to identify the optimal storage duration of incubated eggs of Dandarawi hens on embryonic mortality, hatchability, one-day chick weight and viability of chicks at 14 days of age. Eggs were collected 4 times daily for 15 consecutive days and stored at 16°C and 70% RH until sorted into treatments and then were incubated for 21 d under standard incubation conditions. The ...

Marigold flower extract (MFE), a natural source of xanthophylls, was added to the diets of hens at different concentrations (0, 150, 250, and 350 mg/kg of diet) to determine the effects of MFE on hen performance, physical characteristics of egg quality, and carotenoid content of the egg yolk of hens housed in enriched cages. Additionally, the highest dose of MFE (350 mg/kg) was tested under com...

The amniote egg was a key innovation in vertebrate evolution because it supports an independent existence in terrestrial environments. The egg is provisioned with yolk, and development depends on the yolk sac for the mobilization of nutrients. We have examined the yolk sac of the corn snake Pantherophis guttatus by the dissection of living eggs. In contrast to the familiar fluid-filled sac of b...

Chicken egg yolk was found to contain a unique glycosphingolipid pattern not seen in other types of tissue or cell. These glycosphingolipids were isolated in pure form and their structures established by sequential enzymic hydrolysis and permethylation analysis. The major gangliosides in chicken egg yolk are N-acetylneuraminosylgalactosylceramide, N-acetylneuraminosyl-lactosylceramide and di-N-...

The experiment was designed to evaluate the optimal concentration of egg yolk in extender for diluting Barbari buck semen during short-term storage at 4oC. A total of four Barbari bucks were used as semen donors during the experiment. The observed mean (±SE) valuesrecorded for percent live spermatozoa ranged from 63.5 ± 1.08 to 75.33 ± 0.99, percent progressive motile spermatozoa ranged from 54...

Carbonic anhydrase is an enzyme that plays important roles in the conversion of carbon dioxide to bicarbonate, acid-base balance, and in subembryonic fluid formation in the early Japanese quail embryo. While turkey egg storage longer than 10 d is known to increase the rate of embryo mortality, little is known of the biological mechanisms that contribute to this phenomenon. In this study, we exa...