ACUTE HEPATIC AND RENAL TOXICITY IN LAMBS DOSED WITH FUMONISIN-CONTAINING CULTURE MATERIAL

To examine the effects of acute exposure to fumonisin-containing cultu re material (FCCM), 15 crossbred wether lambs were dosed intraruminall y with FCCM containing 0 (CONTROL, n = 3), 11.1 (LOW, n = 4), 22.2 (ME D, n = 4), or 45.5 (HIGH, n = 4) mg of total fumonisins (B-1, B-2, and B-3)/kg BW daily for 4 d. Blood samples were collected daily, and on d 11 lambs were killed and necropsied. Changes in serum constituents i n fumonisin-treated lambs indicative of liver damage, included increas ed (P < .05) activities of alkaline phosphatase, gamma-glutamyl transf erase, aspartate aminotransferase, and lactate dehydrogenase. Serum co ncentrations of cholesterol, triglycerides, urea nitrogen, and creatin ine were also increased (P < .05) in lambs dosed with FCCM. Hemoglobin tended to increase (P = .07) and white blood cell count tended to dec rease (P = .08) in HIGH lambs and activated partial thromboplastin tim e tended to decrease (P < .10) in lambs dosed with LOW and MED treatme nts. Mitogen-induced lymphocyte blastogenesis was not different(P = .1 4) among treatments. Feed intake markedly decreased (P < .01) followin g the first dosing of FCCM and continued to decline throughout the stu dy. Ruminal VFA concentrations and pH tended to decrease (P < .10) at d 11 in treated lambs. Relative liver and kidney weights (g/100 g of B W) increased (P < .05) in fumonisin-treated lambs. Histological examin ation revealed tubular nephrosis and mild hepatopathy in dosed lambs. Lambs receiving the HIGH treatment died on d 3, 4, 5, and 7 of the stu dy and on d 9 one lamb on the MED treatment died. Diarrhea and letharg y were observed in fumonisin-treated lambs. Fumonisin-containing cultu re material dosed orally is acutely toxic to sheep, affecting primaril y liver and kidney function.