EN
The objectives of the work were to establish the influence of different management conditions on fertility of 119 cows kept either in tying stalls (group 1) or in a oovered yards (group II). At the day of oestrus clinical examination of the reproductive tract was done and the samples of blood to determine the content of kortyzol were taken. At 'the next day the ovaries were examined to determine the ovulation. The mean level of blood kortyzol in pregnant and unpregnant cows were similar. A mean content of blood plasma kortyzol in group I was 9.5 ng/ml and was singificantly lower than in cows from group II (p ^ 0.01). In the group II a percent of fertilization was higher (41%), it was the result of a better determination of oestrus. In the group II of a significantly lower percent of fertilization (p 0.05; 22.6%) were observed tendencies to a premature insemination.