Reproduction Abstracts

Introduction: Hypothyroidism is the disorder influences on reproduction of many species, including dogs. However the results are different, even among the same species.

Materials and methods: The concentration of TSH with species-specific monoclonal anti-TSH in dogs hypothyroidism was evaluated. TSH concentration was measured with a chemiluminescent ELISA solid phase two-point (TSH canine Immulite, DPC, LA, CA). Coefficients of variation within one were 5.4 and 3.8% respectively, with TSH concentrations 0.2, 0.5 and 2.6 mg/l. The inter indicators of variation were 6.3 and 8.2% at the level of TSH respectively 0.16 and 2.8 mg/l.

Results: The average TSH concentration in all the dogs was found to be normal. Nevertheless the increased TSH concentration (0–0.6 ng/ml) was found only in 5% dogs especially in females suffer from galactorrhoea. The reproduction disorders were not clinically detected in hypothyroidism dogs.

Discussion: The possible cause of the galactorrhea coexists with arterial hypertension is lack of the negative feedback of the HT in the hypothalamus causes the increase of TRH furthermore stimulates the secretion of prolactin according to the experimental results The significant increase in IGF1 follows the hyperprolactinemia. In hypothyroid dogs the increased basic GH secretion is directly related with primary hypothyroidism s causes increased serum IGF1 concentrations. The presence of the biendocrine cells produce simultaneously GH as well as TSH was confirmed. The transdifferentiation of the pituitary somatotrope cells into the tyrosomatotropic cells causes the GH increase in hypothyroid dogs according to the experimental results.