T-2 toxin mycotoxicosis in the guinea-pig

Purified T-2 toxin dissolved in saline-dimethylsulphoxide (DMSO) 10:1 (v/v) was administered by gastric intubation in single doses of 1.85, 2.52, 3.45 and 4.66 mg/kg body weight to male guinea-pigs. The acute oral LD₅₀ in the male guinea-pig was estimated to be 3.06 (2.38-3.93) mg/kg. Single doses of 2.5 or 5.0 mg T-2 toxin body weight administered orally in ethanol-DMSO, 1:1 (v/v) resulted in gross lesions including gastric and caecal hyperaemia and haemorrhage, watery-fluid distension of the caecum, oedematous intestinal lymphoid tissue and adrenal gland hyperaemia. Histological alterations included necrosis of lymphoid tissue, bone marrow and tetses, and necrosis and ulceration of the gastro-intestinal tract, most severe in the stomach and caecum. Guinea-pigs, treated orally with T-2 toxin dissolved in saline-DMSO, 10:1 (v/v) at the rate of 0.5 mg/kg/day for 21 days and then 0.75 mg/kg/day for 21 days, remained clinically normal and did not have gross or microscopic lesions, but a moderate leucopenia and an absolute lymphopenia were observed. Oral administration of T-2 toxin to guinea-pigs at a rate of 0.9 mg/kg/day for 27 days produced neither clinical disease nor gross and microscopic lesions, but did produce a decrease in erythrocyte numbers, a leucopenia and an absolute lymphopenia. Alterations in erythrocyte morphology and a marked decrease in the lymphocyte content of the bone marrow were also noted.