Genetic correlation coefficients between egg quality traits were studied using fiftysix harco pullets raised under standard management practices. The estimates were carried out at 22-week, 26-week, 30-week and 32-week of age. Egg quality traits studied include egg weight (EW), shell thickness (ST), haugh unit (HU), yolk index (YI) and shape index (SI). Zero to slight negative correlation coeffi...

The seed beetle Stator limbatus adjusts egg size in response to the quality of the oviposition host, laying small eggs on the high quality host, Acacia greggii seeds, and larger eggs on the poor quality host, Cercidium floridum seeds. We examined various proximate mechanisms of this egg-size plasticity. Once exposed to a new host, it takes 24 to 48 h for females to change the size eggs they lay...

this present study was conducted to evaluate the effects of dietary inclusion of 4, 8 and 12 g kg-1 phytogenic feed additives mixture on performance, egg quality, ovary parameters, serum biochemical parameters and yolk trimethylamine level in laying hens. the results of experiment have shown that egg weight was increased by supplementation of 12 g kg-1 feed additive whereas egg production, feed...

A total number of 225 Fayoumi hens 34 weeks old , were used in this experiment to study the effect of supplementing layer diet with 0.2% casein (c) with or without 0.015% iodine as 0.02% potassium iodide (KI) in drinking water on the performance and egg quality. The experiment continued for 90 days. Birds were randomly divided into three groups , each group contained 3 replicates of 25 each . B...

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...