Data/hora: 11/06/2024 04:36:57

Provedor de dados: | Revista Brasileira de Zootecnia
País: | Brazil
Título: | Causes of rejection of beef bulls in breeding soundness evaluation
Autores: | Menegassi,Silvio Renato Oliveira; Barcellos,Júlio Otávio Jardim; Peripolli,Vanessa; Borges,João Batista Souza; Bernardi,Mari Lourdes.
Data: | 2012-07-01
Ano: | 2012
Palavras-chave: | Behavior assessment; Libido; Mounting capacity; Reproductive assessment.
Resumo: | The objective of this study was to analyze the rates of rejection in the different steps of the breeding soundness evaluation of beef bulls in the state of Rio Grande do Sul, Brazil. The breeding soundness of 22,113 young and mature bulls of 14 beef breeds, participating in the Program of Reproductive Evaluation (PARTO) was evaluated in the experiment. Data concerning to the causes of rejection in the four steps of the breeding soundness evaluation (general physical examination, genital tract examination, semen evaluation and sexual behavior assessment) were analyzed by the Chi-square test and univariate regression analysis. According to year, general physical examination, genital tract examination and semen evaluation determined the rejection of 0.9% to 2.5%, 5.1% to 7.7%, 1.8% to 5.3%; and 4.2% to 6.7%, 7.3 to 9.3%, and 2.5% to 5.5% of young and mature bulls, respectively. Mature bulls presented higher chances of rejection than young bulls in the general physical examination in every year evaluated; as to the genital tract examination, their chances of rejection were higher in years I and II, but not in year III. In the semen evaluation, there was no difference between the ages assessed in any of the three years evaluated. Sexual behavior assessment accounted for the rejection of 1.9 to 6.0% of the young bulls and 2.9% to 3.9% of mature bulls, in accordance with the years evaluated; in years I and II, mature bulls presented higher rejection rates than young bulls. These results confirm the importance of performing all steps of the breeding soundness evaluation, including the sexual behavior assessment as a work routine, rather than an additional, optional stage of the evaluation, which should be carried out before the breeding season. The results indicate the relationship between bull age and rejection rate in the breeding soundness evaluation.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982012000700013
Editor: | Sociedade Brasileira de Zootecnia
Relação: | 10.1590/S1516-35982012000700013
Formato: | text/html
Fonte: | Revista Brasileira de Zootecnia  v.41 n.7 2012
Fonte: | info:eu-repo/semantics/openAccess