| dc.description.abstract | From selection prior to the production of their first lifters, 101 Yorkshire x Landrace
sows were allocated to be ad libitum fed either a control (CE) or high energy diet (HE)
during each of four successive lactations. Diets CE and HE supplied 13.7 and 15.6
MJ. DE kg-I, respectively. Sows were treated similarly during each gestation.
Although HE sows tended to have a greater digestible energy intake, they lost more
weight during each lactation (P<0.05). Maternal weight gains between each farrowing
decreased with successive parities (P<0.05). Litter size at the second and subsequent
farrowings was greater (P<0.05) for the HE than CE sows. The overall mean
litter size for the HE and CE sows was 10.1 and 9.3 piglets, respectively. A similar
trend was noted for live births (9.7 vs. 8.9) and numbers weaned (8.3 vs. 7.9). There
was no consistent effect of treatment on pig weights at birth or 2l d of lactation. No
treatment or parity effects were evident for preweaning pig mortality. The weaning
to conception interval was longer for HE sows in the first parity (14.9 vs. 1l.l d),
but more CE sows were culled for reproductive problems. No treatment effects were
noted for mean interval to conception, proportion mated within 8 d or subsequent farrowing
rate in parities 2, 3 or 4. There was no effect of initial gilt breeding weight
on the ability to produce up to four litters. It is concluded that low lactation digestible
energy intake may limit subsequent litter size. | en |
