Use of reduced doses of eCG applied by different routes in the TAI program in Santa Ines sheep

Semina: Ciências Agrárias. 2015;36(3):1347-1354 DOI 10.5433/1679-0359.2015v36n3p1347

 

Journal Homepage

Journal Title: Semina: Ciências Agrárias

ISSN: 1676-546X (Print); 1679-0359 (Online)

Publisher: Universidade Estadual de Londrina

Society/Institution: UEL

LCC Subject Category: Agriculture: Agriculture (General)

Country of publisher: Brazil

Language of fulltext: Portuguese, English

Full-text formats available: PDF

 

AUTHORS

Karla Dias Antunes-Melo (Universidade Federal de Minas Gerais)
Veronaldo Souza de Oliveira (Universidade Federal de Sergipe)
Anselmo Domingos Ferreira Santos (Universidade Federal de Sergipe)
Claudio Alvarenga de Oliveira (Universidade de São Paulo)
Lícia Mendes Mendonça (Universidade Federal de Sergipe)
Julianne Santiago Silva Goveia (Universidade Federal de Sergipe)
Thiago Santos Almeida (Universidade Federal de Sergipe)

EDITORIAL INFORMATION

Double blind peer review

Editorial Board

Instructions for authors

Time From Submission to Publication: 8 weeks

 

Abstract | Full Text

The aims of this study were to improve the cost-benefit ratio of the application of artificial insemination in fixed time (TAI) by the transcervical route in sheep, to test the dosage reduction and the use of the vulvar submucosa (VSM) route as an alternative for the application of equine chorionic gonadotropin (eCG) on the efficiency of the synchronization protocol and fertility to artificial insemination (AI) and to measure the level of cortisol in ewes as a result the application of this biotechnique. Blood samples were collected before AI, immediately after AI and seven days after AI. Six groups of twenty animals were used, and each group received doses of 200, 300 and 400 IU of eCG by the intramuscular route (IM) and VSM. Estrus was detected, and 48 hours later, the inseminations were performed by the transcervical route. Among the 120 treated ewes, 87.5% came in estrus. The percentage of the intrauterine deposition of semen was 88.3%. The pregnancy rate ranged from 20 to 70% between treatments, with an average of 46.66%. The VSM route was viable for the application of eCG in doses of 300 and 400 IU. The reduction in the eCG dose to 200 IU by the IM route reduces costs while maintaining the efficiency of estrus synchronization protocols and TAI with frozen semen in Santa Ines ewes. The average levels of cortisol were significant, at 1.15, 2.86 and 0.52 ?g/dL according to the three collections, being higher after the animal was off the easel at the end of AI. The procedures for performing the transcervical AI technique indicate that stress in the animals produces satisfactory fertility results and a low cost in multiparous ewes of the Santa Ines breed.