High-fibre diets for ad libitum feeding of sows during lactation

Abstract

ABSTRACT1. Two diets, containing either 400 g oat husks (OH) or 300 g straw (ST) per kg, given ad libitum during a 7-week lactation, were compared with a conventional control diet (C) given in restricted amounts. Eight sows per treatment were used in a randomized-block experiment.2. Mean daily intakes of dry matter during lactation were 4·87, 7·79 and 5·80 kg for the C, OH and ST diets respectively (P>0·001).3. There were no significant differences between diets in number or weights of piglets per litter either at 21 days of age or at weaning.4. Mean changes in live weight during lactation were –9·8, +5 1 and –16·8kg for sows on the C, OH and ST diets respectively (P<0·01). Sows that gained weight during lactation tended to lose more in the 7 days following weaning.5. There were no significant differences in either milk yield or composition. However, the fat content of milk tended to be higher for sows given the two fibrous diets.6. Mean apparent digestibility coefficients for dietary dry matter were 0·82, 0·63 and 0·59, and for nitrogen were 0·81, 0·75 and 0·63, in the C, OH and ST diets respectively. The rate of passage of the ST diet through the gut was significantly faster than that of the other two diets (P>0·001), which were similar.