ALTERATIONS IN THE PERFORMANCE, HEMATOLOGY AND CLINICAL BIOCHEMISTRY OF GROWING LAMBS FED WITH AFLATOXIN IN THE DIET

Twenty-three male lambs were fed 2.5 ppm of aflatoxin for 21 days, Thi rteen lambs constituted the control group, Twelve lambs given toxin an d six from the control group were killed at 21 days, The remaining ani mals were killed 8 days later, To determine haematological and biochem ical parameters, samples of blood were obtained at 0, 7, 14 and 21 day s of exposure and at 1, 2, 4 and 8 days after exposure, The most sensi tive indicator of intoxication was the reduction in body weight (17 +/ - 2.2 kg(-1) body wt. in intoxicated lambs and 19.2 +/- 1.8 kg(-1) bod y wt. in the control group; P much greater than 0.01) and in the avera ge daily weight gain (133 +/- 79 g day(-1) in the intoxicated group an d 254 +/- 105 g day(-1) in the control group; P much greater than 0.00 1) from the 14th day onwards, Lambs fed with aflatoxins had relatively smaller liver weights and higher kidney and spleen weights than lambs from the control group, Feeding aflatoxins increased the erythrocyte count and the mean corpuscular haemoglobin concentration and decreased the mean corpuscular volume and mean corpuscular haemoglobin values, An elevation in the levels of globulins with an increase of the beta a nd gamma fractions and no variation in total protein and albumin was o bserved in lambs fed on aflatoxins, Urea levels and the alkaline phosp hatase and glutamate dehydrogenase enzymatic activities decreased as a consequence of intoxication, whereas gamma-glutamyl transferase was i ncreased, During the clearance period, haematological values regressed towards basal values, but biochemical parameters remained unchanged, These results suggest that lambs are sensitive to the toxic effects of the aflatoxins and that the determination of zootechnical parameters is a better aid to the diagnosis of intoxication than haematological o r biochemical analyses.