Cottonseed meal (gossypol) toxicosis in a swine herd
Haschek, W.M.; Beasley, V.R.; Buck, W.B.; Finnell, J.H.
Journal of the American Veterinary Medical Association 195(5): 613-615
1989
ISSN/ISBN: 0003-1488 PMID: 2777708 Document Number: 340736
Cottonseed meal (CSM) that contained a high concentration of free gossypol was inadvertently used as a protein supplement, without appropriate iron supplementation, for a swine herd in Illinois. 50% of 300 grower and finishing pigs died, and an additional 20% became ill during a 4- to 6-week period. Clinical signs included respiratory distress and abdominal distension. At PM examination the hearts were diffusely pale, flaccid, and rounded because of dilatation of all 4 chambers, the livers were large and congested, and hydropericardium, hydrothorax, and ascites were evident. Histological changes consisted of diffuse myocardial fibre atrophy with perinuclear vacuolation, and multifocal myocardial and skeletal muscle necrosis. Changes in the liver included marked centrilobular congestion, loss of hepatocytes, and fatty degeneration. Differential diagnoses included monensin, selenium, and gossypol toxicoses, and vitamin E/selenium deficiency. Analysed feed samples did not contain monensin. Feed selenium concentrations ranged from 428 to 1513 micro g/kg, and iron concentrations from 160 to 180 mg/kg. Cottonseed meal (3 to 10%) was detected by feed microscopy. A sample of the 40% protein supplement contained 19% CSM and 1300 mg of free gossypol/kg, whereas feed samples contained 200 to 400 mg of free gossypol/kg.