Published online by Cambridge University Press: 02 September 2010
Sixty-six multiparous hybrid Camborough female pigs and their litters were housed in groups of five or six at day 20 post partum. A boar was added to each group on day 21. Four groups (a total of 22 sows) were fed to appetite (TA), to requirement (R) or to 0·70 of requirement (RO·70). Average daily sow food intakes were 8·2, 61 and 4·5 kg for TA, R and RO·70 respectively. Significant differences occurred in live-weight changes between grouping and weaning (TA>R>RO·70; P<0·001). TA sows were heavier at weaning than either R or RO·70 sows (P< 0·001).
Oestrus occurred during lactation in 0·68, 0·73 and 0·18 of sows, on average 11·3, 13·4 and 8·0 days following grouping respectively, for TA, R and RO·70 sows but these differences were statistically non-significant. The average non-return rate at day 21 was 0·69, with no differences between treatments.