Effect of Bentonite as a natural adsorbent to ameliorate the adverse effects of aatoxin B1 on performance and immune systems in broiler chicks

The objective of this experiment was to evaluate the effect of Bentonite as a natural adsorbent to ameliorate the adverse effects of aflatoxin B1 on growth performance and immune systems in broiler chicks. A total of 256 Ross 308 one-day-old broiler chicks were randomly divided into 4 treatments, with 4 replicate pens per treatment and 16 chicks per pen based on a completely randomized design. The following dietary treatments were applied: 1) Basal diet not containing AFB1or Bentonite (control), 2) Basal diet + 5 g/kg Bentonite, 3) Basal diet + 1 mg/kg AFB1, 4) Basal diet + 1 mg/kg AFB1 + 5 g/kg Bentonite. The broiler chicks were fed the experimental treatments from 1 to 35 days of age. Performance parameters were recorded weekly. At d 28, two birds of each replicate were randomly selected and injected with sheep red blood cell antigens. At the end of experiment, four birds in each treatment group were sacrificed for measurement of relative weight of various components of carcasses and lymphatic organ weights in broiler chickens. The results indicated that aflatoxin B1 decreased significantly the BW gain, feed intake and impaired feed conversion ratio in starter and grower periods compared to the control diet (P< 0.05). The addition of Bentonite to diet ameliorated significantly the negative effects of 1 mg/kg of AFB1 on feed intake and weight gain (P< 0.05) but no significant effect on feed conversion rate. Aflatoxin B1 significantly decreased antibody response to the SRBC antigen and bursa of Fabricius relative weight. The addition of bentonite in the contaminated diet not significantly alleviated the inhibitory effect of aflatoxin B1 on immunity parameters. Feeding AFB1 alone caused significant increases in the relative weights of livers and preventiculos compared with the control (P< 0.05). It is concluded that addition of Iranian Bentonite used in the present study could alleviate the adverse effects of aflatoxin B1 in growing broiler diets and this product can be used as a suitable toxic adsorbent in poultry nutrition up to 5 gr/kg.