Effect of progressive fasting on physiological criteria of adult Warren SSL hens.

: The present study examined the effects of 3 days and 7 days of feed deprivation-as used in artificial moulting programs -on several metabolic criteria in adult Warren SSL hens. Body weight decreased gradually during the fasting period. Abdominal fat pad content decreased only during the first 3 days of fasting and no further during the following 4 days of feed deprivation. The fasting-induced changes in plasma glycerol and uric acid levels confirmed these proportional changes in body composition. In both fed and prolonged fasting (7 days) conditions, glucagon stimulated the in vitro lipolytic activity of abdominal adipose tissue explants. Chicken growth hormone stimulated the in vitro lipolytic activity of adipose tissue from fed but not from hens fasted for 7 days. The relationship between these physiological changes during progressive fasting in the adult hen and energetic and amino acid requirements is discussed.