Comparative study of macroscopic and microscopic on thyroid gland of apparently healthy ruminants (Cow, Sheep and Goat)

The aim of this study was to examine the lesions of thyroid gland in apparently healthy ruminants. For the first time disease of thyroid gland have been recorded in all kinds of animals. A total of 360 pairs (90 each from sheep and goat and 180 from cow) of thyroid which showed various macroscopic abnormalities were collected for detailed examination. The samples were fixed in 10% formalin salin، the tissue were processed through routine method for paraffin embedding. Sections cut at 5-7 μm were stained by hematoxylin and eosin method. The pathologic conditions observed in thyroid glands of these animals included of simple colloid goiter: goat 12 (13. 3%) cow 21 (11. 66%) sheep 14 (15. 5%). Hyperplastic goiter: goat 43 (47. 7%) sheep 30 (33. 3%). parenchymal cysts: goat 3 (3. 33%) cow 22 12. 2%)sheep 8 (8. 9%). Ultimobranchial nodules: goat 7 (7. 7%) sheep 16 (17. 8%) Follicularatrophy: goat 10 (11. 1%) cow 11 (6. 66%) sheep 5 (5. 5%). Inflammatory and degenerative lesions: goat 4 (4. 4%) cow 12 (6. 6%) sheep 2 (2. 2%). Without lesion: goat 11 (12. 2%) cow 114 (63%) sheep 15 (16. 6%). Finding of a high number lesions in these animals is interesting، since there is paucity of report in these domestic animals. This needs further investigation to elucidate our result.