Abstract #W478

# W478
Evaluation of the use of hCG to promote the induction of reproductive activity in anovulatory Alpine goats.
Alan S. Alvarado-Espino1, Cesar A. Meza-Herrera2, Vicente H. Gonzalez-Alvarez1, Juan M. Guillen-Muñoz1, Martha V. Perales-Garcia1, Raymundo Rivas-Muñoz3, Evaristo Carrillo3, Francisco G. Veliz*1, 1Universidad Autonoma Agraria Antonio Narro, Torreón, Coahuila, Mexico, 2Universidad Autonoma Chapingo-Unidad Regional Universitaria en Zonas Aridas, Bermejillo, Durango, Mexico, 3Instituto Tecnologico de Torreon, Torreon, Coahuila, Mexico.

The aim of this study was to evaluate the efficacy of the use of human chorionic gonadotrophin hormone (hCG) to induce reproductive activity in Alpine goats during seasonal anestrous in northern Mexico (26°N). Adult anovulatory goat (n = 30) were randomly divided into 3 groups according to body condition score (1.96 ± 0.32) and weight (37.36 ± 8.48). On July 23 (day −1), all goats received intra-vulvo-submucosal (ivs) administration of 20 mg of progesterone. On day 0 (D0), goats in the groups G300, (n = 10) received an ivs administration of 300 UI of hCG, the group G100, (n = 10) received 100 UI of hCG while the control group GC, (n = 10) received 0.5 mL of saline solution plus intramuscular administration (im) of 7.5 mg of synthetic prostaglandin. After D0, the onset of estrous behavior was evaluated twice a day for 5 min during the first 5-d after hCG administration by a sexually active buck. Goats were scanned by transrectal ultrasound (7.5 MHz probe) on d-45 after breeding for detection of pregnancy. Goats depicting estrus behavior were similar between groups (G100: 100% and G300: 90%, P > 0.05), with not estrus behavior in the GC-goats. The onset of estrous occurred earlier in G100 than G300 (54 ± 6.32 h vs 76 ± 30 h, respectively; P < 0.05). No differences were found (P > 0.05) in pregnancy rate between G100 (100%) and G300 (70%) groups. The kidding rate and prolificacy were similar (P > 0.05) in the G100 and G300 (80 vs 70% and 1.5 ± 0.56 vs 1.57 ± 0.53, respectively). These results indicate that administration of 100 UI of hCG could be used without a reduction in both estrus behavior and reproductive outcomes in anestrous Alpine goats at 26° N.

Key Words: hCG, induction, estrous