Abstract/Summary

The supplementing of sow diets with lipids during pregnancy and lactation has been shown to reduce sow condition loss and improve piglet performance. The aim of this study was to determine the effects of supplemental palm oil (PO) on sow performance, plasma metabolites and hormones, milk profiles, and pre-weaning piglet development. A commercial sow ration (C) or an experimental diet supplemented with 10% extra energy in the form of PO, were provided from d 90 of gestation until weaning (24-28 d post-partum) in two groups of 8 multiparous sows. Gestation length of PO sows increased by 1 day (P<0.05). Maternal body weight changes were similar throughout the trial, but loss of backfat during lactation was reduced in PO animals (C: -3.6±0.8 mm; PO: -0.1±0.8 mm; P<0.01). Milk fat was increased by PO supplementation (C d3: 8.0±0.3% fat; PO d3: 9.1±0.3% fat; C d7: 7.8±0.5% fat; PO d7: 9.9±0.5% fat; P<0.05) and hence milk energy yield of PO sows was also elevated (P<0.05). The proportion of saturated fatty acids was greater in colostrum from PO sows (C: 29.19±0.31 g/100g of fat; PO: 30.77±0.36 g/100g of fat; P<0.01). Blood samples taken on 105 days of gestation, within 24 hours of farrowing, day 7 of lactation and at weaning (28 ± 3 days post-farrowing) showed there were no differences in plasma concentrations of triacylglycerol, non-esterified fatty acids, insulin or insulin-like growth factor-1 throughout the trial. However, circulating plasma concentrations of both glucose and leptin were elevated during lactation in PO sows (P< 0.05 and P<0.005, respectively) and thyroxine was greater at weaning in PO sows (P < 0.05). Piglet weight and body composition were similar at birth, as were piglet growth rates throughout the pre-weaning period. Seven days after birth, C piglets contained more body fat, as indicated by their lower fat free mass per kg (C: 66.4±0.8 arbitrary units/kg; PO: 69.7±0.8 arbitrary unit/kg; P<0.01), but by day 14 of life this situation was reversed (C: 65.8±0.6 arbitrary units/kg; PO: 63.6±0.6 arbitrary units/kg; P<0.05). Following weaning, PO sows exhibited an increased ratio of male to female offspring at their subsequent farrowing (C: 1.0±0.3; PO: 2.2±0.2; P<0.05). We conclude that supplementation of sow diets with PO during late gestation and lactation appears to increase sow milk fat content and hence energy supply to piglets. Furthermore, elevated glucose concentrations in the sow during lactation may be suggestive of impaired glucose homeostasis.