Studies performed in vitro suggest that a novel 12 amino acid RF amide peptide, isolated from the quail hypothalamus, is a gonadotrophin inhibitory hormone (GnIH). The aim of the present study was to investigate this hypothesis in the domestic chicken. Injections of GnIH into nest-deprived incubating hens failed to depress the concentration of plasma luteinizing hormone (LH). Addition of GnIH t...

Changes in blood concentrations of ionized calcium and total calcium were measured in broiler breeder hens (42 wk old) relative to egg cycle and environmental temperatures. Two environmental temperature treatments were used: 1) temperature cycled daily from a low of 10 C at 0300 h to a high of 25 C at 1600 h; and 2) temperature cycled from a low of 21 C at 0300 h to a high of to a high of 39 C ...

Ornithobacterium rhinotracheale (ORT) is a recently identified bacterial pathogen of poultry, linked to the respiratory disease complex of broilers and the economic losses associated with that disease complex. Present control measures applied for the disease include the continuous use of in-feed antibiotics. A recently developed bacterin vaccine that is applied to broiler-breeder hens to pass o...

The current studies were undertaken to assess the ability of humoral immune response in breeding hens and the protective immunity provided by administration of purified Salmonella gallinarum (SG) porins to the progeny. Two hundred and ten broiler breeder hens, 53 weeks old, were divided into three groups and subcutaneously immunized via multiple sites at 0 and 10 days with either: a) 10 μg SG p...

in this experiment 180 azerbaijan province native laying hens from 28 to 40 weeks were separated in 6 treatments and 3 replicates (10 birds per replicate) as a (2 × 3) factorial arrangement of treatments in a completely randomized design. treatments included two levels of dried tomato pomace (dtp) (8 and 16%) and 3 types of using methods (unprocessed, alkali and acid processed). the results sho...

Broiler breeder hens were used to determine the effect of drinking water containing a low concentration of a chemical mixture (arsenic, 0.8 ppm; benzene, 1.3 ppm; cadmium, 5.1 ppm; lead, 6.7 ppm; and trichloroethylene, 0.65 ppm) and a high (10 times greater than the low concentration of the chemical mixture) levels of the chemical mixture. These chemicals are present in ground water near hazard...

An experiment was conducted to evaluate the effects of either a low-fat (8% of total calories) or high-fat (47% of total calories) diet on Large White breeder females maintained at a constant (21 C) or a cyclic temperature regimen (12 to 27 C). Each diet was fed to 32 hens individually caged in the cyclic condition and 46 in the constant condition. Energy consumption, reproductive performance, ...

Three experiments were conducted to compare the effects of feeding blends of grains naturally contaminated with Fusarium mycotoxins on brain regional neurochemistry of laying hens, turkey poults, and broiler breeder hens. In Experiment 1, thirty-six 45-wk-old laying hens were fed diets including the following for 4 wk: 1) control, 2) contaminated grains, and 3) contaminated grains + 0.2% polyme...