Use of an uterine infusion of seminal plasma at the onset of heat and its effect on ovulation, farrowing rate and litter size in gilts

摘要

The role of seminal plasma (SP) on the fertility of female pigs has been widely discussed in the last few years. SP has an important role in (he physiological events associated with fertilization. If infused at the onset of oestrus, it reduces the interval between the onset of heat and ovulation, being an efficient mechanism to decrease the high variation in fhe time of ovulation of pigs. This is due to the presence of high concentrations of oestrogen in the semen, which promotes the liberation ofPGF2 alpha, after uterine infusion, inducing ovulation and helping in sperm transport, which ultimately influences fertilization rales. Through a surgical model, in which one of the uterine horns is clamped, it was possible to observe by ultrasonographyan advancement of the ovulanon in the ovary of the intact horn, after SP was infused. Ultrosonography has been the method of choice to follow up follicular development and to determine the moment of ovulation in these experiments. Better fertility results as a consequence of larger litter size with the use of SP have been described in some studies, but not in others. This study aimed at evaluating the effect of intra-uterine infusion (UI) of SP in gilts in the beginning of oestrus on oestrus length (OL), time of ovulation (TO), relation between TO and OL, return to oestrus rate (RE), farrowing rate (FR) and utter size (LS).