The thin sow—observations on digestive efficiency, nitrogen balance and carcass composition

Abstract

SUMMARYMeasurements were made of apparent digestibility of dry matter, nitrogen and lipid, nitrogen balance, pancreatic lipase activity and carcass composition in eight non-pregnant sows during three 10-day balance trials during which the feed intake was 1·1, 0·8 and 2·6 kg/day of a diet containing 14·69% crude protein and 3·0 Meal gross energy/kg DM.All the sows had similar breeding histories and had completed their fourth lactation. Four were in standard condition (mean body weight, 160 kg) and four in thin condition (mean body weight, 134 kg). All the animals lost weight and were in negative nitrogen balance while on the two lower levels of feed intake; the thin sows lost significantly more N than the standard animals (P< 0·05) and on the lowest level of feeding digestibility of DM by the thin sows was significantly less (P< 0·001).In both groups there was a rapid recovery in nitrogen retention and in body weight when the food intake was increased.