Fertilidade de éguas crioulas após aspiração folicular

Abstract

Transvaginal ultrasound-guided follicle aspiration is a non-invasive procedure for oocyte recovery from live animals. In equine medicine there are a few studies about this technique, so there is lack of information. Therefore, to evaluate the effect of follicular aspiration on subsequent fertility in mares, two experiments were conducted using an ultrasound with a setorial probe (5.0MHz). On the first experiment, fifteen Criollo mares were not aspirated and fifteen were assigned to one of three groups according to the diameter of the aspirated follicle: 25-29mm (n=4; Group 1); 30-34mm (n=6; Group 2) or > 35mm (n=5; Group 3), all of them in oestrus. On the second experiment, the follicular aspiration was performed in twenty five mares during dioestrus and thirty one were used as control mares. The number of follicles aspirated was between 4 and 8 and all visualized follicles were aspirated. Follicle aspiration was performed when at least four follicles (> 5mm) were present on both ovaries. In the Experiment I, the pregnancy rates were 75.0% (Group 1), 83.3% (Group 2), 60.0% (Group 3), and 73.3% (Group 4 - Control). In the Experiment II, pregnancy rates were 76.0% in aspirated group and 77.4% in control group. On both experiments, pregnancy rates were similar in treated and control mares (P>0.05). So far the study indicated that next cycle fertility was not affected by the follicular aspiration.