Effects of dietary aflatoxin (AF) and the antibiotics lincomycin (L) and tylosin (T) were evaluated in growing crossbred pigs. Six barrows (3 replicates of 2 each, mean body weight 14.0 kg) per group were assigned to 1 of 6 treatment groups (for a total of 36): 0 mg L, 0 mg T, and 0 mg AF/kg of feed (control); 220 mg L/kg of feed (200 g/ton); 110 mg T/kg of feed (100 g/ton); 2.5 mg AF/kg of feed; 2.5 mg AF plus 220 mg L/kg of feed; 2.5 mg AF plus 110 mg T/kg of feed. Barrows were administered their respective diets for 28 days. Body weight, body weight gain, and feed consumption were reduced by the AF alone, the AF plus L, and the AF plus T treatments, compared with control, L, and T treatments. Altered serum biochemical or hematologic mea surements induced by AF treatments included increased serum activities of alkaline phosphatase and γ-gluta myltransferase, increased hematocrit, hemoglobin, RBC count, WBC count, and mean cell hemoglobin, decreased serum concentrations of albumin, cholesterol, inorganic phosphorus, unsaturated iron binding capacity, total protein, and urea nitrogen, and decreased lymphoblastogenic response. Liver weight was increased, and microscopic lesions were consistent with those observed in cases of aflatoxicosis. With some other minor exceptions for hematologic and immunologic variables, these data indicate that the feed antibiotics lincomycin and tylosin, when added to aflatoxin-contaminated diets, do not have beneficial or detrimental effects on aflatoxicosis in growing swine.
