Improving feed efficiency remains crucial for poultry production. Birds have previously been selected on their ability to digest their diet, as assessed by AMEn (Apparent ME corrected for 0 nitrogen). Such selection, for either a high (D+) or a low AMEn (D-), affects energy, nitrogen, lipid, and starch digestibility. The aim of this study was to establish whether selection on the digestive abil...

An experiment was conducted to determine the differences in body weight (BW), feed intake (FI) and some egg production traits of two strains of layer chickens (Isa Brown and Nera Black) and correlate the relationships between the tested traits. The study commenced when the layers were 26 weeks old and a total of 200 (100 of each strain) were used. Sixty fresh eggs (30 from each strain) were col...

Mouse populations differing in metabolic rate have been developed through selection for high (MH) and low (ML) heat loss, along with the unselected controls (MC). Objectives of the study were to compare the MH, ML, and MC lines for feed intake, growth, body fatness, and organ weights when reared at 12, 22, and 31 degrees C, and investigate potential line x environment interactions. Feed intake ...

this experiment was conducted in international researchery institute of sturgeon fishes shahid  dadman. the basal diet contained fish meal as protein source (cp=40%). five diets were supplemented with 5 graded levels of methionine, (0, 0.5,1 ,1.5, 2% met per kg diet) . each diet was randomly assigned to triplicate groups of 195 juvenile huso huso (initial weight 31.9± 2.8) in fiftin 500-l circu...

a semi-field study was carried out to evaluate the effect of two medicinal herbs, individually and in combination, on growth performance, carcass traits, nutrient digestibility and immune response of broiler chickens.  a total of 384 one-day-old straight-run arbor acres broiler chickens were allocated into 24 floor pens prepared in a commercial broiler house. pen-groups were fed one of the foll...

A QTL that explained a large proportion of the phenotypic difference between broiler and layer chickens in an experimental cross was evaluated in a commercial broiler line. A three-generation design, consisting of 15 grandsires, 608 half-sib hens, and more than 50,000 third-generation offspring, was implemented within the existing breeding scheme of a broiler breeding company. Four markers from...

The relationships between conformation and longevity traits were analysed in 58 493 Czech Fleckvieh cows first calved from 1994 to 2003. All cows were scored for conformation during the first lactation. Genetic correlations between longevity and conformation traits were estimated by bivariate runs using the VCE 4.0 program for variance component estimation. The values of heritability for confor...

an experiment was conducted to determine the differences in body weight (bw), feed intake (fi) and some egg production traits of two strains of layer chickens (isa brown and nera black) and correlate the relationships between the tested traits. the study commenced when the layers were 26 weeks old and a total of 200 (100 of each strain) were used. sixty fresh eggs (30 from each strain) were col...