Effect of mycotoxins contaminated corn on growth nutrient digestibility and in vitro rumen fermentation in goats

Abstract

Two trials (in vivo and in vitro) were conducted to evaluate corn naturally contaminated with mycotoxins, majority being aflatoxin B1 (AFB1) on the performance, nutrient digestion and rumen fermentation in growing goats. China Lezhi black goats (12), weighing 16.39 to 16.45 kg, were fed with the diet of 40% concentrate (the mycotoxin naturally contaminated diet containing 74.49 μg/kg AFB1, 2.08 μg/kg AFB2, 59.71 μg/kg DON and 36.51 μg/kg ZEN) for 28 days. The results showed that the contaminated corn had no significant effect on feed intake but decreased the average daily gain (ADG) and feed conversion ratio (FCR) in growing goats. Digestibility of crude protein (CP) in the trial group was significantly lower than the control group and the digestibilities of acid detergent fibre (ADF) and neutral detergent fibre (NDF) decreased too, but not significantly. Neither volatile fatty acid (VFA) nor pH was significantly different between the 2 groups. The ammonia nitrogen (NH3-N) in the trial group was lower in both in vivo trial and in vitro trial (0 h to 3 h). In in vitro experiment, ruminal fluids were collected from 4 China Lezhi goats and incubated at 39°C for 48 h with control corn or AFB1 contaminated corn. The total gas production and gas production rate in the trial group were significantly lower than the control group. These reductions showed the negative effects of the naturally contaminated AFB1 corn on nutrient digestibility and rumen function in growing goats.