Dietary fat preference and effects on performance of piglets at weaning

OBJECTIVE An experiment was to evaluate the interplay of dietary lipid sources and feeding regime in the transition from sow milk to solid food of abruptly weaned piglets. METHODS Soon after weaning, 144 piglets were selected and were trained over a 15 day period to experience gradually reducing dietary fat content from 12% to 6% for lard (L), soybean oil (S), and coconut oil (C) and their feeding behavior and diet preference then tested in a behavior observation experiment. Another 324 weaned piglets were used in three consecutive feeding experiments to measure the effect of different dietary fats on performance and feed choice in the four weeks after abrupt weaning. The lipid sources were used as supplements in a 3% crude fat corn/soya basal diet, with 6% of each being included to form diets 9C, 9S, and 9L respectively, and their effects on performance measured. Combinations of these diets were then further compared in fixed blends or free choice selection experiments. RESULTS Piglets pre-trained to experience reducing lipid inclusion showed different subsequent preferences according to lipid source, with a preference for lard at 9%, soybean oil at 3%, and coconut oil at 6% inclusion rate (p<0.001). Following abrupt weaning, whilst after 4 weeks those fed 9C had the heaviest body weights (18.13 kg, p = 0.006). Piglets fed a fixed 1:1 blend of 9C+9S had a poorer feed conversion ratio (FCR = 1.80) than those fed a blend of 9C+9L (FCR = 1.4). The 9C and 9L combination groups showed better performance in both fixed blend and free choice feeding regimes. CONCLUSION After abrupt weaning, they still have dependence on high oleic acid lipids as found in sow milk. A feeding regime offering free choice combination of lipids might give the possibility for piglets to cope better with the transition at weaning, but further research is needed.