Sincronización de celos en ovejas y cabras con dispositivos intravaginales liberadores de progestágenos: alteraciones en ambiente vaginal y su relación con la fertilidad Estrous synchronization with intravaginal devices in sheep and goats: alterations in vaginal environment and its' relation with fertility

Intravaginal devices impregnated with progesterone or progestagens are widely used for estrous synchronization in ewes and goats. However, due to several causes, the fertility obtained with these treatments is lower than in a spontaneous estrus. The presence of these devices in the vagina induces an increase of the vaginal biota, changes in its composition, histological and cytological alterations in the vaginal wall. The main bacterial growth is based in Gram negative coliforms (E. coli y Klebsiella spp.). An important reduction in conception rates can be achieved to vaginitis. The accumulation of bacterial and inflammatory products in the vagina affects the sperm viability. Recently we have observed that the spermatozoa functionality and viability is affected after co-incubation with vaginal mucus collected from ewes pretreated with intravaginal sponges. Overall, the results of treatments with intravaginal devices are affected by the ovarian response but also by the changes induced in the normal vaginal environment.