CTSD (Cathepsin D) is a key enzyme in yolk formation, and it primarily affects egg yolk weight and egg weight. However, recent research has mostly focused on the genomic structure of the CTSD gene and the enzyme's role in pathology, and less is known about the enzyme's functions in chickens. In this paper, the correlations between CTSD polymorphisms and egg quality traits were analyzed in local...

The influence of dietary oxidized oil was studied on laying hen performance, egg quality and blood metabolites.  Experiment was conducted on 160 laying hens (Hy-Line W-36, 54-61 wk of age) in a completely randomized design with five treatments and four replicated cages containing eight birds per cage. Dietary treatments replaced fresh soybean oil in the control diet (3% fresh soybean oil, 15.25...

A mapping population segregating for egg quality traits was created by a line cross between two egg layer lines and screened by a genome scan. The F2 generation consisted of 307 hens, which were scored for egg quality and production traits. The mapping population was genotyped for 99 microsatellite loci, spanning nine macrochromosomes and five small linkage groups. The linkage maps were used in...

This experiment was designed to evaluate the effects of different sources of calcium at different rates and cholecalciferol(Vitamin D3) on the performance and egg quality of Hy-line W-36 Laying hens. In this study a total of 648 hens were managed in a completely randomized design using a factorial arrangement of 3 × 3 × 2 treatments, with three calcium sources (oyster shell, OS; ground limeston...

This experiment was conducted to evaluation the effects of different levels of untreated and treated green grape leaf with urea on performance, egg quality traits and blood parameters of laying hens. In this experiment 192 Hy-Line (w-36) laying hens, 35 to 46 wk of age were divided in to 4 treatments with 4 replicates (12 birds per replicate) in a completely randomized design experiment. The tr...

this experiment was designed to evaluate the effects of different sources of calcium at different rates and cholecalciferol(vitamin d3) on the performance and egg quality of hy-line w-36 laying hens. in this study a total of 648 hens were managed in a completely randomized design using a factorial arrangement of 3 × 3 × 2 treatments, with three calcium sources (oyster shell, os; ground limeston...

an experiment was conducted to investigate the effects of using different levels of red pepper powder (rp) and marigold flower powder (mf) on egg production, egg yolk color andsome blood metabolites in laying hens. ninety, 103-weeks old laying hens were divided into 5 treatments groups of 6 birds in each cage with 3 replicates in a completely randomized design. the birds were fed a corn-soybean...

Three White Leghorn strains, their two-way crosses, and two commercial lines were used to evaluate the effects of aging on heterosis (H), reciprocal effects, and additive (A), Z-chromosome (Z), and heterotic effects and their variances on egg quality traits during the first laying cycle. Egg weight (EW), specific gravity (SG), Haugh unit (HU), and albumen height (AH) were measured at 240, 350, ...

this experiment was conducted to evaluate and compare antibiotic, organic acid, probiotic and prebiotic effects on performance, egg quality and blood metabolites in commercial laying hens. the experiment was a completely randomized design with 160 laying hens strain hy line (w-36) from 32 to 42 weeks of age with 5 treatments and 4 replicates of 8 hens each. the experimental treatments consisted...