Follicular dynamics in mares paso fino colombiano at Sabana of Bogotá Colombia

Abstract

The purpose of this study was to determine the daily follicular growth and the time in which ovulation will occur, in Paso Fino Colombian mares who were pastured at the Sabana de Bogotá Colombia in tropical conditions, with an altitude of 2.652 meters over sea level, average temperature of 12º C and 1500 mm3 of rainfall. As previously stated, reproduction’s biotechnologies used in Colombia have led to manage and follow all the mares cycle, by monitoring follicular dynamics in order to obtain better results and therefore there is not information about some follicular aspects in this Colombian breed. For this project, fifty (50), mares were used with ages ranged between 5 and 10 years. To collect data from the selected mares, regular intervals of ultrasound were done every other day until the ovulation occurred, in order to keep track of follicular growth, taking into account the dominant follicle (25-30 mm), and detectable uterus edema, since its recognition until their ovulation, performing the same measurements on the scale that is found on the ultrasound screen. The data was analyzed by descriptive statistics, with deviation standard, plus an F test for unequal and equal variances, to determine differences in the follicular size of ovulation and daily follicular growth between the right and left ovary. It was concluded that paso fino colombian mares had a daily follicular growth of 2,04 + /-63 mm, a size follicular to ovulation of 41,34 + /-2,14 mm, of the 50 estrous cycles analyzed, 60% was by the left ovary and 40% by the right ovary. Differences in size of follicular ovulation were not significant (P> 50) among the ovaries. But in the daily follicular growth there were some mayor significant differences (P <02) meaning that the right ovarian follicles had a greater growth than those of the left ovary. With these results it was demonstrated that ovarian activity of Colombian paso fino mares in tropical conditions is similar to other breeds in other countries with similar sizes. Finally we concluded that the paso criollo colombiano’s mares have more ovulations in the left ovary, according to these results.