Data/hora: 02/06/2024 07:44:12

Provedor de dados: | 65
País: | Brazil
Título: | Reproductive performance of Nellore heifers raised in extensive system undergoing different vaccination protocols in fixed-time artificial insemination (FTAI)
Autores: | Schillings Neto,Ernest; Nogueira,Eriklis; Jardim,Rodrigo; Abreu,Urbano Gomes Pinto de; Sterza,Fabiana Andrade de Melo; Pellegrin,Aiesca Oliveira; Juliano,Raquel Soares.
Data: | 2019-01-01
Ano: | 2019
Palavras-chave: | Beef cattle; Immunization; Leptospirosis; Pregnancy rate; Viral diseases.
Resumo: | ABSTRACT:  This study evaluated the reproductive performance of Nellore heifers without previous vaccination undergoing fixed-time artificial insemination (FTAI) and subsequent natural breeding under different vaccination protocols against infectious bovine herpesvirus 1 (BHV-1), bovine viral diarrhea virus (BVDV), and bovine leptospirosis (BL). A total of 763 animals were included; the group assignment was as follows: T1, control without vaccination; T2, vaccination against BL; T3, vaccination against BHV-1and BVDV; T4,vaccination against combination of BL + BHV-1and BVDV. Vaccination was started 30 days before FTAI (D-40), and a booster dose was administered at D-10. Serological tests were used to verify the occurrence rate of natural infection by BL, BHV-1, and BVDV. Initial pregnancy was diagnosed at D30, D60, and D120 after FTAI. Final pregnancy rates were evaluated by group, weight, body-condition score, occurrence of estrus, inseminator, bull, and occurrence of abortions or embryonic death. In all groups, results indicated seropositivity of 100% for leptospirosis, 77.0-94.0% for BHV-1, and 64.0-87.0% for BVDV. The vaccination protocol was not a significant influencing factor of pregnancy rate and embryonic or fetal mortality; whereas, animal weight at the beginning of the breeding season and presence of estrus at FTAI were significant influencing factors of pregnancy rate. The vaccination protocol had no interference with the reproductive performance of the experimental groups.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782019001100701
Editor: | Universidade Federal de Santa Maria
Relação: | 10.1590/0103-8478cr20180902
Formato: | text/html
Fonte: | Ciência Rural  v.49 n.11 2019
Fonte: | info:eu-repo/semantics/openAccess