Posterior paralysis in a calf caused by cattle grubs (Hypoderma bovis) after treatment with a systemic insecticide for grub control
Cox, D.D.; Mozier, J.O.; Mullee, M.T.
Journal of the American Veterinary Medical Association 157(8): 1088-1092
1970
ISSN/ISBN: 0003-1488 PMID: 5529077 Document Number: 30824
A calf became recumbent with posterior paralysis on the third day after being sprayed with trichlorphon. It lost weight and did not react to stimuli or respond to treatment with antihistamines, chymotrypsin or dexamethasone. It was killed after 27 days. Both living and dead larvae of Hypoderma bovis (L.) were found in the epidural space and fat between the thoracic and lumbar vertebrae, and larvae of H. lineatum (Vill.) were recoverd from the oesophagus and trachea. Necrosis of a portion of the spinal cord had been caused by pressure from a haemorrhage. Post-mortem examination of an untreated calf from the same source revealed Hypoderma larvae in similar situations, but there was no paralysis or haemorrhage. The mechanism by which larvae apparently cause haemorrhage after treatment with insecticide is not known. Early treatment is recommended to avoid this reaction.