Four years of induction/synchronization of estrus in dairy goats: effect on the evolution of eCG binding rate in relation with the parameters of reproduction

Abstract

-Ninety-eight Alpine goats of two herds were followed over 4 years in a program of annual artificial insemination after estrus induction/synchronization, including progestagen administration (vaginal sponge) followed by prostaglandin analog and equine chorionic gonadotrophin (eCG) 48 h before sponge removal. Goats were sampled every 4 hours from the 16th to the 56th following sponge removal, for determination of LH surge and tested for estrus by the presence of a buck. Seven days after AI, endoscopic examination of the ovaries was performed to determine the number of corpus lutea. Pregnancy diagnosis was performed at day 21-22 post AI by determination of plasma progesterone and at day 40-45 by ultrasonography. Parturition, number and sex of kids were recorded. All the goats were sampled before and after each treatment, for anti-eCG antibodies screening. Statistical analysis of the results clearly established a significant effect of the treatments on antieCG antibodies. Time of estrus and LH surge were significantly different between herd. The antibodies significantly delayed the time of coming out of estrus as well as the time of LH surge. Two antagonistic effects were evidenced: first, the delayed of time of estrus and time of LH surge in relation with the immune reaction to eCG; secondly, the ahead of time of estrus and time of LH surge during the Reprod. Nutr. Dev. 41 (2001) [401][402][403][404][405][406][407][408][409][410][411][412] 401

Reproductive efficiency of adult and prepubertal goats subjected to repeated follicular aspiration

“…Roy et al (1999), De Ruigh et al (2000 and Drion et al (2001) have mentioned the hypothesis of antibody formation resulting from prolonged use of exogenous hormones, such as anti-eCG and anti-FSH, which may compromise oocyte recovery. The likelihood of inducing FSH antibody formation is increased in goats treated with porcine FSH, thereby decreasing the ovarian response after the third application (Remy et al, 1991), which would result in treatment failure.…”

Evaluation of out-of-season estrus induction protocols in progesterone-primed mix-breed dairy goats using eCG, GnRH and E2

“…Despite eCG being a commonly used glycoprotein, there is an amplified immune response when such treatment is carried-out in a recurrent fashion (Drion et al 2001). Moreover, if sustainability of most animal production systems is to be achieved, such animal systems must redesign out-ofseason ovulation induction protocols considering appropriate standards of animal welfare while decreasing the use and (or) dose of external hormones, since their use has been strictly regulated in several countries (Simoes 2015).…”

Effects of Long and Short-Term Progestagen Treatments Combined with PMSG on Oestrus Synchronization and Fertility in Awassi Ewes during the Breeding Season

“…Progestagen analogues have been widely used in small ruminants to induce and synchronize oestrus (Baril et al 1993;Romano 1996;Greyling et al 1997;Vinoles et al 1999a;Simonetti et al 2000;Vinoles et al 2001;Drion et al 2001;Ataman et al 2005;Zeleke et al 2005;Dogan and Nur 2006;Emsen and Yaprak 2006). Recent studies (Vinoles et al 2001;Ataman et al 2005;Zeleke et al 2005) have focused on the duration of the progestagen-based synchrony treatments.…”