Tumors of the thymus in cattle, sheep, and pigs.

SUMMARY A histologic survey has been made of all neoplasms found in slaughtered catde, sheep, and pigs during one year in 100 abattoirs throughout Great Britain. A total of 302 tumors from cattle, 107 from sheep, and 139 from pigs was collected. The specimens included 16 thymomas (15 from cattle and one from sheep) and 80 thymic lymphosarcomas (40 from cattle, 5 from sheep, and 35 from pigs). Thymomas were found only in adults, whereas thymic lymphosarcoma had a high incidence in immature animals. Of the 16 thymomas, 13 were predomi nantly epithelial tumors and 3 were predominantly lympho cytic. The findings are considered in relation to the character istics of thymic neoplasms in man.