this experiment was conducted to evaluate the effects of different levels of calcium (ca) and phosphorus (p) on performance native hens of khorasan province. a total of 400 native hens from khorasan station were used in a completely randomized design (factorial experiment) with 8 treatments, 5 replicates and 10 hens in each replicate of  age 26 to 50 weeks. eight experimental diets based on cor...

The present research was designed to examine the genetic analysis of egg weight, egg yolk weight and egg albumen weight of Bovan Neva Black laying hens at 25, 51 and 72 weeks. For this purpose, thirty birds were selected from the layer flock in the Babcock University Teaching and Research Farm. They were individually housed in separate labeled battery cage. A total of thirty eggs were collected...

the aim of current study was to determine the effects of vitamin c on bone mineral density (in terms of osteoporosis), eggshell quality and investigation of correlation between these factors in laying hens reared under normal condition. one hundred and ninety two 24 - weeks - old laying hens diet was supplemented with 4 levels of vitamin c (0, 250, 500 and 750 mg/kg diet). the experimental desi...

The objectives of our study were to propose a new definition for persistency of egg production and to develop a mathematical model to describe the egg production curve, one that includes a new measure for persistency, based on the proposed definition, for use as a selection criterion to improve total egg production. Persistency of egg production is an important determining factor for total egg ...

Egg production curves describe the laying patterns of hen populations over time. The objectives of this study were to fit the weekly egg production rate of selected and nonselected lines of a White Leghorn hen population, using nonlinear and segmented polynomial models, and to study how the selection process changed the egg-laying patterns between these 2 lines. Weekly egg production rates over...

this study was conducted to evaluate the effects of different levels of butyric acid triglyceride and prebiotics on performance, egg quality traits and blood lipids of laying hens.  a 2 × 4 factorial experiment with 4 levels of butyric acid triglyceride (0%, 0.15%, 0.30%, 0.45%) and 2 levels of prebiotic (0 and 0.15%) based a completely randomized design were conducted. one hundred and ninety-t...

effects of mating sex ratios on production performance in indian peafowl were investigated at punjabwildlife research institute, gatwala faisalabad. research was conducted from may through august 2007 toexplore the most productive mating sex ratio. the sex ratios have a significant effect on egg production.maximum mean eggs (1.63) were produced by the sex ratio 1:2 while maximum egg fertility (...

An experiment was conducted to evaluate the effects of different levels of mineral and vitamin premix on performance and egg traits of laying hens from 37 to 49 weeks of age. Two hundred and forty laying hens (Hy-Line W-36 strain) were randomly assigned to 5 dietary treatments of four replicates each with 12 hens per replicate). The levels of mineral and vitamin premixes in the experiment were ...

Growth hormone (GH) has diverse functions in animals, together with other hormones from the somatotropic axis. Here, chicken GH (cGH) was investigated in recessive white chickens and Qingyuan partridge chickens as a candidate gene affecting egg production traits. Chicken egg production traits were studied in association with 4 selected single nucleotide polymorphisms (T185G, G662A, T3094C, and ...