A crossbreeding experiment was carried out between two Egyptian strains of chickens namely Mandarah (MM) and ElSalam (SS). The two purebred strains and their reciprocal crosses (MS and SM) were used to estimate the effect of crossing on egg laying and egg quality parameters, direct additive and maternal additive effects as well as heterosis and direct heterosis percentages for studied traits. R...

A study was conducted to examine the effect of yeast culture residue (YCR) on the suppression of aflatoxicosis in broiler breeder hens. One hundred twenty, 35-wk-old, Cobb broiler breeder hens of the same cross were fed diets supplemented with aflatoxin (AF) (0 or 3 mg/kg) and YCR (0 or 2 lb/ton) singly and combined in a 2 × 2 factorial designed experiment. The birds were randomly assigned to p...

Studies were conducted to determine the effect of chronic v.s. intermittent exposure to T-2 toxin on reproductive performance in adult bobwhite quail. In Experiment 1, 180 hens were orally dosed with 0% (LD ), 20% (LD ), 40% (LD ) or 60% (LD ) of the acute 100% lethal dose of T-2 toxin as determined in a 0 20 40 60 previous experiment. One quarter of the dosage was administered each week for 3 ...

This study was undertaken to determine if pre-storage heating of broiler breeder eggs, stored for long periods, would improve the hatchability and chick quality. A total of 2400 broiler breeder eggs were obtained from a 46 weeks old commercial flock. Eggs were distributed in a 3 x 4 factorial design, with three pre-storage heating durations (0, 6, and 9 hours at 37.5° C and 56% RH) and four sto...

Medaka/Chronic ƒÁ-irradiation/Fecundity /Fertility Eggs of the medaka, Oryzias latipes, were irradiated continuously with 137Cs ƒÁ-rays at exposure-rates of 10, 100 and 1000 R/day from the morula stage to hatching. Newly hatched fry were transferred to non-irradiation field. At one year after hatching medaka were tested for their fecundity and fertility. When irradiated females were mated with ...

Several feeding regimens are applied to improve performance of fertile egg production during times of heat stress. During a period of heat stress (34 to 36 degrees C), two feeding periods were used to measure the impact of feeding time on reproductive performance of Japanese quail (Coturnix cotunix japonica) between 44 and 60 wk of age. Each feeding time treatment had 25 individually caged male...