Estrous and ovulation induction in Saanen dairy goats using different intravaginals devices with or without eCG or male effect

Abstract

The objective of this study was to compare the efficiency of three methods of estrus synchronization in dairy goats. Fifty nine Saanen goats were used and separated in three groups: G-1 (n=20), sponge impregnated with 60mg of medroxiprogesterone acetate (MAP), G-2 (n=19) and G-3 (n=20), CIDR® containing natural progesterone (P4). The devices of G-1 remained in animals for 11 days; on the ninth day it was applied 250IU eCG and 50µg of PGF2α. In G-2 and G-3 the CIDR® remained in females for 5 days; on the third day it was applied 50µg of PGF2α and only the G-2, 250IU of eCG, in the withdrawal of the device. In G-3, 48h before the removal of the device, the male effect began. The natural mountings were performed 20 h after the detection of estrus. The estrus response to the G-1 and G-2 was 100% and 90% in G-3. The average interval between the end of the treatment and estrus onset was 31.53±2.81 h (MAP), 24.39±1.21 h (CIDR®+ eCG) and 43.56±2.19 h (CIDR®+ male effect). The pregnancy and kidding rates and prolificacy was 95%, 80% and 1.83 in G-1, 52.6%, 47% and 1.77 for the G-2 and 61.1%, 50% and 1.70 in G-3, respectively. When compared with the sponge and CIDR®+ male effect, the CIDR®+ eCG anticipates the onset of estrus and synchronize better, on the other hand, the low pregnancy and kidding rates in CIDR® in relation to the sponge, reveals that under these experimental conditions , the sponge is better than the CIDR®. Keywords: Caprines, reproduction, CIDR®, short protocol.