Body Characteristics, Performances and Protein Metabolism in Hy-Line Brown Hens Subject of Natural Moult

Abstract

The paper aimed to present the evolution of food intake, body weight, laying performance, mortality, ovary and oviduct weight and protein metabolism in 63-week-old natural moulted Hy-Line var. Brown hens housed in industrial system. Ingested crude protein, serum protein, albumin, globulins, uric acid, and total manure nitrogen were monitored for eight weeks of moult to characterize the protein metabolism of the hens. Spontaneous moult of the Hy-Line Brown hybrid is characterized by a decrease in food intake by up to 35.0%, a decrease in body weight by up to 31.6%, a significant increase in mortality (1.45% vs. 0.66% in non moulting hens), by stopping of the laying process, a 67.2% decrease of the ovary weight and 54.3% decrease of the oviduct weight versus non-moulted gens. The serum level of uric acid was increased during the period of massive moult revealing a high protein catabolism. Total nitrogen manure was decreased during the period of massive moult, a fact attributed to the decrease in food intake. Eight weeks after the onset of the spontaneous moult process, the reported changes of moulted hens were no longer significantly different from those of non-moulted hens.