Evaluation of subchronic dietary fumonisin B 1 on nutrient digestibility and growth performance of rats

Abstract

Fumonisin B 1 (FB 1 ), a toxin produced by Fusarium verticillioides ( Fusarium moniliforme ) and other Fusarium species which grow on maize worldwide, has been documented to cause various physiological responses in animals. Thirty-nine female Wistar rats randomly assigned to three treatment groups were used to assess the effects of dietary FB 1 on nutrient utilization and growth performance. Each group received one of the three diets containing 0.20, 10.0 and 20.0 mg FB 1 /kg constituting diets 1, 2 and 3, respectively. The animals were weighed weekly and proximate chemical compositions of the diets and the faecal samples collected from the rats on each diet were determined using standard methods. Dietary FB 1 significantly (P < 0.05) influenced nutrient digestibility, feed intake, feed conversion efficiency and relative weight gain. Rats fed diets 2 and 3 had relative weight gains of 87.2 and 66.2% of the rats fed diet 1, respectively. Rats on diet 1 were about 104.5 and 160.6% more efficient in feed conversion compared to those on diets 2 and 3, respectively. Dietary exposure to FB 1 at a concentration of about 10 mg/kg or higher for a period of 35 days is a potential health risk that reduced nutrient utilization by adversely affecting proper nutrient digestion, absorption and/or metabolism, resulting in poor growth rates in Wistar rats. This study revealed that adverse effects of FB 1 on nutrient digestibility and utilization play a significant contributory role in poor growth performance usually associated with animals exposed to diets containing FB 1 . Key words: Fumonisin B 1 , growth performance, mycotoxin, nutrient digestibility, rats.