Physiological Stress in Laying Hens

摘要: Stress responses in laying hens were mediated by continuous infusion of adrenocorticotropin (ACTH) via osmotic pumps. The ACTH was dissolved saline solution (0.85%), and each pump delivered 8 IU per kilogram BW day at the rate 1 microL/h for 7 d. Control received pumps loaded with saline. Measurements made 6 d postpump implantation, unless otherwise indicated. ACTH-treatment increased total carcass, rear half intestinal, liver weights. Proximate analyses showed increases dry weight, moisture, protein, fat, carbohydrate, ash content. Weights front as well weights abdominal fat pad, heart, head, feet, skin unaffected ACTH-treatment. Plasma corticosterone, glucose, cholesterol, high-density lipoproteins ACTH, whereas triglycerides decreased. Feed water intake, excreta, excretory DM all ACTH-treated hens. decreased carbohydrate ash, fiber, gross energy excreta unaffected. did not affect digestibility matter, proteins, carbohydrates, fats, or energy; however, absorption ACTH. Antibody levels to sheep red blood cells, cell-mediated immunity (wattle index phytohemagglutinin-phosphate), relative spleen weight reduced heterophil:lymphocyte ratio increased. Reproduction negatively affected treatment, measured cessation on third atretic follicles, oviduct weight.