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 study was conducted to evaluate the effects of different dietary oil sources supplementation on laying hens’ performance and fatty acids profile of egg yolks. Seventy-two 23-week-old laying hens (Tetra-SL) divided into six experimental diets (four replicates and three birds per replication) in a completely randomized design for nine weeks. Experimental diets were included: 1) control (no oi...

A (3 x 3) factorial arrangement was used in a completely randomized design to study the effect of early nutrition of pullet on subsequent egg production and quality. Three levels of protein and three levels of energy during stages of pullet growth (starter 0-6 wk, grower 7-12 wk and developer 13-18 wk of age) and their effect on laying performance (22-36 wk of age) were evaluated. In all phases...

Abstract—Gastric content’s mass and pH commonly assessed invasively using endoscopic biopsy, or semi-invasively using swallowable transducer. EGG (electrogastrography) is a technique for observing gastric myoelectrical activity noninvasively, that could be designed as mobile device. In this research, 72 EGG recordings were obtained from 13 local white rabbit (Oryctolagus cuniculus). Recorded EG...

1. In a study spanning two breeding seasons, we assessed the effect of different dietary energy and protein levels on body mass, body condition, and egg production of female ostriches. 2. During the first breeding season, groups were given diets with energy concentrations of 8.5, 9.5 and 10.5 MJ/kg dry mass (DM) metabolisable energy (ME) and protein concentrations of 135, 150 and 165 g/kg. In t...

The effect of supplementing two commercial multienzyme to diets included two barley cultivars (Sararood [71.99%] and Valfajr [66.39%]) on performance, egg quality, and blood parameters of laying hens was investigated in an 8-wk (65 to 73 wk of age) experiment.  The commercial multienzymes were Grindazym™ (with mainly β-glucanase and xylanase activity) and Hemicell® (with mainly β-mannanase acti...

Previously, we have measured daily changes (developmental patterns) in embryonic heart rate (fh) in altricial and semi-altricial (ASA) birds (range of mean fresh egg mass approximately 1-20 g), semi-precocial seabirds (egg mass approximately 38-288 g) and precocial birds (egg mass approximately 6-1400 g). An allometric relationship between embryonic fh at 80 % of incubation duration (ID) and fr...

Data of four layers flocks (#31-34) from North Carolina Layer Performance and Management Test of the Department of Agriculture and Consumer Services were used in the meta-analysis to find if an increase in space allowance can affect egg production traits in white and brown layers. Effects of space allowance of 310 and 413 cm2/bird on layers performance were compared in this study. The increase ...

Variations in egg size and composition can have important consequences for the quality of offspring. We investigated the effect of temperature, in the 5 days preceding laying, on yolk, albumen, shell and total egg mass. Moreover, we examined the influence of temperature on three important egg components, i.e. the yolk carotenoids and the albumen lysozyme and avidin. In our experimental conditio...

AIM An experiment was conducted to evaluate the effect of supplementing different levels of salts of organic acid in the laying hen's diet on their production performance and egg quality parameters during a period of 16-week. MATERIALS AND METHODS A total of 140 white leghorn laying hens at 24 weeks of age were randomly distributed to seven dietary treatment groups, i.e. T1 (control), T2 (0.5...