Lymphoreticular lesions in beef cattle at an ontario abattoir.

During the period April 1983 to March 1986, lymphoreticular lesions in cattle were surveyed at an Ontario abattoir. Postmortem examination of 171,157 cattle revealed macroscopic lesions in 696 animals (0.4%). The most frequent finding was abscessation of a single lymph node, a finding that was observed in 353 cases (50.7% of animals with lesions/0.2% of total slaughter). Actinobacillary granulomas were present in 252 lymph nodes (36.2%/0.1%). Other specific lesions included mycobacteriosis and mycotic or parasitic lymphadenitis. Cases of nonspecific chronic lymphadenitis or granulomas in lymph nodes, pigmentations, malformations, hyperplasia, and neoplasia were also seen. Abscesses were the most common splenic lesions. One animal had localized lymphangiectasia of the epicardium.