Bovine neoplasms encountered in Canadian slaughterhouses: a summary.

During the past five and one half years veterinarians of the Food Production and Inspection Branch of Agriculture Canada submitted tissues from 1535 cases of suspected bovine neoplasia for diagnosis to the Animal Diseases Research Institute, Nepean. Neoplasia was confirmed in 1370 cases. Lymphosarcoma was diagnosed in 738 (53.9%) of these cases, but it was not possible to accurately assess the prevalence of this condition at slaughter. Other commonly found neoplasms in order of frequency were neurofibroma, squamous cell carcinoma, uterine carcinoma, adrenal tumors, ovarian tumors and primary liver tumors. Many metastatic anaplastic carcinomas involving lymph nodes were not specifically identified as to tissue of origin. Nonneoplastic lesions were found in 165 submissions.