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The objective of this study was to evaluate the influence of the degree of uterine and ovarian development on the pregnancy rate of Girolando heifers submitted to Timed Artificial Insemination (TAI). Fifty-six heifers, representing 100% of the category in the herd studied, were evaluated. The heifers were submitted to a gynecological evaluation, prior to hormonal treatment, with ultrasonography, in order to measure the diameter of the uterine horns and ovaries, as well as evaluate the presence of corpus luteum (CL) and antral follicles. According to the values found for the uterine and ovarian diameters, the animals were classified into scores from one to three. After the gynecological evaluation, all animals were submitted to TAI. There was no statistical difference (P>0.05) in pregnancy rates between the different uterine and ovarian scores, as well as in relation to ovarian structures. However, a statistical difference (P<0.05) was observed in the percentage of animals in anestrous within ovarian scores one, two and three (83.3%, 37.5% and 42.8%, respectively). The conclusion was that uterine and ovarian development did not interfere in the pregnancy rate of Girolando heifers in the herd studied.
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