Increasing 12 h of intravaginal device permanence allows greater estrus synchrony but lower pregnancy rates in artificially inseminated acyclic dairy goats.

PAULA, C. J. C. de; SOUZA-FABJAN, J. M. G.; PINHEIRO, J. B. S.; GONÇALVES, J. D.; DIAS, J. H.; OLIVEIRA, M. E. F.; FONSECA, J. F. da

Increasing 12 h of intravaginal device permanence allows greater estrus synchrony but lower pregnancy rates in artificially inseminated acyclic dairy goats.

Autores

PAULA, C. J. C. de

SOUZA-FABJAN, J. M. G.

Descripción

This study assessed in dairy goats the effect of hormonal induction treatments varying only 12 h in progestogen device permanence on estrus synchrony and fertility. In both Experiments, goats received 60 mg of medroxyprogesterone acetate (MAP) intravaginal devices for 6 (G6) or 6.5 d (G6.5), and 200 IU of eCG i.m. and 30 ?g of d?cloprostenol were i.m. applied at 24 h or 36 h before device removal, respectively. In Experiment 1 (n = 24), data related to sexual behavior and ovarian ultrasonography were recorded and, in Experiment 2, (n = 83) fertility was assessed after Flexible Time Artificial Insemination (FxTAI). In conclusion, increasing the time of intravaginal device permanence from 6 to 6.5 d resulted in greater estrus synchrony, but lower fertility in dairy goats subjected to estrus induction treatment at the non?breeding season. The G6 treatment resulted in high conception rate and can be recommended to support FxTAI programs in dairy goats in the non?breeding season.

Palabras clave

AI, Corpora Lutea, Follicular dynamics, Ultrasound, Dairy goats, Animal reproduction, Artificial insemination, Anestrus, Corpus luteum, Ultrasonography, Estrus synchronization