Immunocompetence of livestock plays an important role in farm profitability because it directly affects health maintenance. Genetics significantly influences the immune system, and the genotypic structure of modern fast-growing chickens has been changed, particularly after decades of breeding for higher production. Therefore, this study was designed to help determine if intensive breeding progr...

The effect of genetic strain (Ross 308; Cobb 500) and parent flock age (Ross at 32 and 36 weeks; Cobb at 26 and 44 weeks of age) on hatchability, fertile hatchability, Egg Weight Loss (EWL) and egg break out analysis were examined. At each flock age, 300 eggs from each treatment group were incubated. Thirty eggs from each treatment group were labeled individually for the measurements of Egg Wei...

An investigation was carried out to evaluate the growth performance of six commercial broiler hybridsavailable in Iran (Arbor Acres, Arian, Cobb 500, Hubbard, Lohmann and Ross 508). Two hundred and fiftyfertile eggs of each hybrid were taken from different breeder farms, all over the country. The similarity offlocks ages and their health conditions were considered. After hatching, the sexed chi...

BACKGROUND Chickens are animals that are sensitive to thermal stress, which may decrease their production level in terms that it affects feed intake and thus, decreasing body weight gain. The Heat Shock Factors (HSF) and Heat Shock Proteins (HSP) genes are involved in the key cellular defense mechanisms during exposure in hot environments. Aimed with this study to analyze the expression of HSF1...

In a novel approach, monochromatic blue light was used to investigate its modulatory effect on heat stress biomarkers in two commercial broiler strains (Ross 308 and Cobb 500). At 21 days old, birds were divided into four groups including one group housed in white light, a second group exposed to blue light, a 3rd group exposed to white light + heat stress, and a 4th group exposed to blue light...

The aim of the study was to effect biological preparations: phytobiotics (pine needles), probiotics ("Sporobacterin"), immunostimulator "Dorogov Antiseptic stimulator, fraction 2" (ASD-2F) on morphological blood parameters, safety and productivity broiler chickens Cobb-500 cross. studies were conducted 4 groups "Cobb-500" cross, which one is a control three are experimental. During first week l...

A total of 300 one-day old male broilers (Cobb 500) were randomly divided into four treatment groups. The groups comprised of 15 birds each, and were defined by diet and the birds in each group were fed 0 (control), 3, 5, or 7 kGy electron-beam irradiated diets. A total of 5 replicates were performed. The chemical composition of the diet was not affected by irradiation.Irradiation doses of 5 an...