Effect of insertion of Bt gene in corn and different fumonisin content on growth performance of weaned piglets

The objective of this study was to compare the effect of Bt corn and isogenic corn on the growth of weaned piglets. One hundred and twenty-eight weaned piglets weighing 8.8 ±1.27 kg live weight were randomly assigned to 4 groups of 32 animals each (16 castrated males and 16 females). Bt corn (line MON810) and isogenic corn were produced at two farms located in the provinces of Lodi and Venice (northern Italy). The Bt corn had the same chemical composition as the isogenic corn but a lower content of fumonisin B1 (FB1). The experimental period (35 days) was in two phases: 0-14 d and 15-35 d. There was no significant difference in average daily gain (ADG) among groups during the first feeding phase. Compared to animals fed isogenic corn, the piglets fed Bt maize gained more weight during the second feeding phase (Bt: 464.1 g/d, isogenic: 429.1 g/d; P < 0.05). Also, the ADG over the entire trial was higher in piglets fed Bt corn versus piglets fed isogenic corn (Bt: 396.4 g/d, isogenic: 374.1 g/d; P < 0.05). The ADG of the whole period decreased linearly (P <0.05) with respect to the FB1 content of the diet. Final weight was higher in piglets fed the diet containing Bt corn (Bt: 22.68 kg, isogenic: 21.83 kg; P < 0.05). No differences in feed intake and in the feed:gain ratio were observed, although a linear response between FB1 and feed:gain ratio in first 14 days of the experiment was detected.