T. S. Nelson

Digestion of Feed by Chicks with Pale Bird Syndrome

Unaffected chicks (normal) and chicks with pale bird syndrome (pale) were fed a control diet or a test diet obtained from the broiler house containing the pale chicks. Pale birds digested less (P less than 0.05) dry matter and ether extract than normal chicks, and the nitrogen content in their feces was greater. The chicks from both sources digested more (P less than 0.05) dry matter from the test feed but also excreted more (P less than 0.05) nitrogen than those fed the control diet. Neither diet resulted in differences in the digestion of ether extract. The cause of pale bird syndrome was related more to source of chicks rather than source of feed. Depigmentation may have resulted from decreased pigment absorption because of reduced absorption of dietary components, including ether extract.

Effect of age of maternal flock and strain on the incidence of tibial dyschondroplasia in growing chicks.

Two experiments were conducted to study the effects of age of the maternal flock (27 vs. 57 weeks of age at time the eggs were set) and strain of broiler chicks (Cobb 500, Ross, Arbor Acres, and Avian) on the incidence of tibial dyschondroplasia (TD) in broiler cockerels grown to 3 weeks of age. The chicks were fed a corn/soybean meal-based diet containing 3145 kcal metabolizable energy corrected for nitrogen retention (MEn)/kg, 24% protein, and 0.50% available phosphorus. Each treatment was replicated four times with eight chicks per pen. In Expt. 1, chicks from the old parent flock had significantly higher body weights (P < or = 0.05) than those from the young parent flock. There were no significant differences in feed efficiency or incidence of TD. In Expt. 2, body weights, feed efficiency, and TD were unaffected by strain.

Effect of minerals on the incidence of leg abnormalities in growing broliler chicks

Abstract Experiments were conducted to determine the effect of the mineral content of the diet on the incidence of varus deformation and dyschondroplasia in broiler chicks grown to 3 weeks of age. Blood samples were analyzed for pH, pCO 2 , bicarbonate and base excess. Experiment 1 had a 2×3 factoral arrangement of treatments with. 25 or .50% available phosphorus and .60, .90 or 1.20% calcium. Experiment 2 employed a 2×2×2 factoral treatment arrangement with .40 or .80% available phosphorus, .60 or 1.20% calcium and 0 or .36% added magnesium. In Experiment 1, increasing the phosphorus content of the diet decreased (P