RESUMO
In our study, a clinical and reproductive examination was undertaken in 204 dogs of five different breeds. Thyroxine and thyroid-stimulating hormone plasma concentrations were assayed in order to assess the real incidence of hypothyroidism associated with reproductive disease. Among these animals, only two breeds were affected by hypothyroidism (4.5% of the Dogue de Bordeaux and 2.4% of the Leonbergers). Moreover, these animals did not suffer from any reproductive disease. Our study showed also that 70% of the male Dogue de Bordeaux were hypothyroxinemic compared with Great Danes, English Mastiff and Leonbergers whose male population was 100% normothyroidic. We found the same tendency in bitches. In our data, there was no difference in thyroxin plasma concentrations between normo- and hypofertile dogs, but our results were not statistically significant.