Induction of estrus in non-lactating dairy goats with different estrous synchrony protocols

• Published in: Animal reproduction science Vol. 85; no. 1; pp. 117 - 124
• Main Authors: Fonseca, J.F., Bruschi, J.H., Santos, I.C.C., Viana, J.H.M., Magalhães, A.C.M.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 2005
• Subjects: Administration, Intravaginal; Animals; body condition; body weight; Breeding; Chorionic Gonadotropin - administration & dosage; cloprestenol; Cloprostenol - administration & dosage; controlled internal drug release devices; Cross-Over Studies; dairy animals; eCG; equine chorionic gonadotropin; Estrous induction; Estrous synchrony protocols; estrus; Estrus - physiology; Estrus Detection; estrus synchronization; Estrus Synchronization - metabolism; Female; Goat; Goats - physiology; medroxyprogesterone; Medroxyprogesterone Acetate - administration & dosage; nannygoats; prostaglandins; Time Factors; Toggenburg; eCG; Goat; Estrous synchrony protocols; Estrous induction
• ISSN: 0378-4320; 1873-2232
• DOI: 10.1016/j.anireprosci.2004.03.005

The objective of this study was to evaluate two protocols of estrous synchronization in non-lactating Toggenburg goats. Nineteen goats were allocated, according to body condition score and weight, into two groups (A and B) and evaluated utilizing two treatments (T1 and T2). Animals in the T1 and T2 groups received an intravaginal sponge (day 0) containing 60 mg medroxyprogesterone acetate for 6 and 9 days, respectively, plus 200 IU equine chorionic gonadotrophin (eCG) and 22.5 μg cloprostenol 24 h before sponge removal. Females were bred only at the second estrus and received 22.5 μg cloprostenol 7 days later to prevent pregnancy. Percentages of animals in estrus did not differ ( P>0.05) between T1 (89.5%) and T2 (84.2%). From 33 females in estrus (T1+T2), 28 (84.8%), 2 (6.1%), and 3 (9.1%) were identified in estrus at 06:00, 12:00 and 18:00 h, respectively. Additionally, 6 (18.2%), 0 (0.0%) and 27 (81.8%) were no longer detected to be on estrus at 06:00, 12:00 and 18:00 h, respectively. Interval from sponge removal and the onset of estrus (IE) did not differ ( P>0.05) between T1 (46.1±15.0 h) and T2 (53.6±16.1 h). Duration of estrus did not differ ( P>0.05) between T1 (30.0±12.0 h) and T2 (27.2±11.2 h). Both protocols were effective in inducing estrus in non-lactating goats. The onset and end of the estrus relative to hour of the day should be considered in estrous detection, natural breeding, and artificial insemination in goats.