The aim of this study was to investigate hypothyroidism and avitaminosis A in aborted ewes, regardless of the cause of abortions, by measuring the levels of T₃, T₄, TSH, vitamin A and β -carotene in the sera.

A total number of 204 Akkaraman ewes ages between 2 and 7 years were used in the study. Of these, 57 were pregnant and 147 aborted ewes.

Ewes were allocated into 4 different groups; two control and two experimental groups. There were 30 ewes from the surrounding villages in the control group 1, and 27 pregnant ewes brought up indoors in the control group 2. 69 ewes from the vicinity with the risk of hypothyroidism and 78 ewes from the vicinity without risk were allocated in the experimental groups 1 and 2 respectively.

In the experimental group1, the levels of T₃ and T₄ in 1.4%, β -carotene in 4.9% and vitamin A in 51.0% of the ewes; in the experimental group 2, the levels of T₃ in 3.7%, β -carotene in 27.6% and vitamin A in 73.4% of the ewes were found to be below the critical levels.

Means of these parameters in other groups except the means of vitamin A in group 2 were not calculated below the critical level.

A significant positive correlation was obtained between vitamin A and β -carotene levels in all groups (p<0.001) and between total and free T₃ and T₄ levels with variation amongst the groups in terms of the level of significance. In contrast, a significant negative correlation was observed between vitamin A and total T₄, and between free and total T₃ and TSH levels (p<0.05).

No diagnosis of hypothyroidism was made in aborted ewes in the vicinities with and without risk of hypothyroidism. However, β -carotene and vitamin A levels of the ewes were found below the confidence level in the aforementioned proportions.