This study was conducted to determine the effect of hen production cycle (HPC) and the effect of egg weight (EW) at the same egg production level on egg quality, egg composition, hatchability, duckling quality, and first-week BW in Pekin ducks. For HPC, hatching eggs were obtained from different Pekin-duck breeder flocks, aged 31 wk for the first production cycle (HPC1) and 78 wk for the second...

In this work the cholesterol content of chicken eggs produced by two lines (high and low weight) representing the 31st generation of selection for divergent growth was studied. Divergent selection for body weight at 8 weeks of age resulted in changes in egg size and consequently in the weight of egg components. Higher values (P≤0.001) were observed in eggs from the high weight (D+) line for egg...

1. Despite considerable recent interest in plasma and yolk testosterone (T) in female birds, relatively little is known about environmental regulation of female T, individual variation in female T or the relationship between plasma and yolk T. 2. In breeding females of a wild population of dark-eyed junco ( Junco hyemalis ), we assessed variation in the responsiveness of the hypothalamo-pituita...

Twenty-four, 79-wk-old White Leghorn hens were assigned randomly to three diets containing 0, 2.5, or 5.0% conjugated linoleic acid (CLA). The diets were fed for 4 wk to determine the effect of dietary CLA on quality characteristics of eggs. Eggs were collected daily and stored at 4 C for 1, 7, 21, or 49 d. At the designated times, the eggs were processed to evaluate water content, fatty acid c...

This study examines the influence of ascorbic acid pretreatment on ethanol clearance, toxicity, and behavioral impairment after an acute dose of ethanol in humans. Ascorbic acid or a placebo was given to 20 healthy male subjects for 2 weeks before ethanol consumption. The dose of ethanol was 0.95 gm/kg body weight and was consumed during a 2 1/2-hour period. Thirty minutes after ethanol consump...

Low level intake of drugs from the ingestion of contaminated feed may lead to residue problems in food animals. Sulfadimidine (SDD) was used as a model to determine the residue risk at various doses in laying hens. The drug was administered as a single intravenous injection (100 mg kg(-1) body weight, BW), as a single oral dose (100, 30, 10, 3, 1 mg kg(-1) BW) and via medicated feed for 7 conse...

Different animal models have been used to study the effects of prenatal protein undernutrition and the mechanisms by which these occur. In mammals, the maternal diet is manipulated, exerting both direct nutritional and indirect hormonal effects. Chicken embryos develop independent from the hen in the egg. Therefore, in the chicken, the direct effects of protein deficiency by albumen removal ear...

The social environment can have profound effects on an individual's physiology and behaviour and on the transfer of resources to the next generation, with potential consequences for fecundity and reproduction. However, few studies investigate all of these aspects at once. The present study housed female Japanese quail (Coturnix japonica) in pairs or groups to examine the effects on hormone conc...

background   lipoprotein lipase activity can be increased by clofibrate. clofibrate is used to reduce serum triglyceride level in adults. the aim of this study was to determine the effect of clofibrate on serum triglyceride and cholesterol level after administration of intravenous lipid in very low birth weight neonates. method in a randomized double blind placebo – controlled study, 60 very lo...

A study was conducted to test the inclusion rates of corn dried distillers grains with solubles (DDGS) in laying hen diets on egg production (EP) parameters for a full production cycle. Two hundred eighty-eight Bovan Single Comb White Leghorn laying hens were fed diets containing 0, 5, 10, 15, 20, or 25% DDGS from 24 to 46 wk and 47 to 76 wk of age for Phase I and Phase II, respectively. The di...