Effects of dietary lecithin and fat unsaturation on nutrient utilisation in weaned piglets

This report describes a digestibility experiment performed on 48 (Landrace×Large White) male, post-weaned pigs of initial age 21 days. Diets were prepared according to a 3×2 factorial design and included two lecithin levels (0 or 10 g/kg diet) and three fat sources: soyabean oil, lard or a 0.8 soyabean oil/0.2 lard blend. There were no significant effects of dietary lecithin supplementation or vegetable oil source on dry matter, crude protein and crude fibre digestibility. A significant effect of dietary fat source was observed for fat digestibility (P=0.005). No effect of dietary lecithin was shown on fat digestibility, but it could be observed a tendency to a significant interaction between lecithin and dietary fat (P=0.097). Digestibility of C16:0 was affected by fat source (P=0.006), with soyabean oil diets showing the highest value in all cases. Digestibility of C18:1 was not affected by dietary fat source or lecithin. However, an interaction of time×lecithin (P=0.027), in which the effect of lecithin was more pronounced during the first experimental period was observed. Digestibility of C18:2 was unaffected by lecithin, but a tendency for an interaction of time×lecithin was observed (P=0.067), in which lecithin exerted a higher effect during the 2 weeks that followed weaning than the following 2 weeks. Digestibility of C18:2 was nevertheless higher in the diet rich in soyabean oil than in that containing lard (P<0.05).