The effects of low levels of aflatoxin B1 on health, growth performance and reproductivity in male rabbits

Abstract

This study investigated the chronic effects of relatively low exposure to aflatoxin B1 (AFB1) on the growth performance, immune situation and reproduction in male rabbits. Bucks (n=32, 4.82±0.22 kg) were individually assigned to 4 treatments (8 replicates each) using a randomised complete block design. Four diets containing 0, 0.02, 0.05, and 0.1 mg AFB1/kg, were provided to bucks for 8 wk. Growth performance and semen quality were measured. Blood, organ and tissue samples were collected to measure haematological indices, liver function, organ weights and immune parameters. Compared to control, AFB1-contaminated diets reduced body weight and average daily gain (<em>P</em><0.05), altered certain haematological indices and liver function with decreased monocytes percentage and mean corpuscular haemoglobin concentration, and increased plateletcrit and albumin (<em>P</em><0.05), slightly impaired reproductive parameters with enhanced ratio of morphologically abnormal sperm cells at early stage and reduced post-stage acrosome integrity, testis weight and serum testosterone concentration (<em>P</em><0.05), decreased immune function with reduced relative liver weight (%) and tumour necrosis factor-α levels in serum and liver tissue, and increased serum 8-hydroxy-2’-deoxyguanosine levels (<em>P</em><0.05). Furthermore, bucks fed diets with relatively high AFB1 (0.05 and 0.1 mg AFB1/kg) had reduced red blood cell and haematocrit (<em>P</em><0.05) in contrast with the low AFB1 group (0.02 mg AFB1/kg). In conclusion, diets containing 0.05 and 0.1 mg AFB1/kg had negative effects on bucks’ growth performance, haematology, reproductivity and immune function, whereas diet containing 0.02 mg AFB1/kg had only minor effects on the parameters measured.