Data/hora: 01/06/2024 16:43:59

Provedor de dados: 	109	
País: 	Colombia	
Título: 	Economic evaluation of puberty induction of nulliparian Nellore heifers using intravaginal device and melengestrol acetate	
Autores: 	Pereira,Luiz Carlos; de Souza Ferreira,Renan; Fujii Gongalves,Rony; Vinhas Ítavo,Luís Carlos; Signor Kohl,Endyara; Menezes Dias,Alexandre; Barbosa Ferreira,Marcos; Espínala Carvalho,Cristiano Marcelo; Gongalves Mateus,Rodrigo.	
Data: 	2019-09-01	
Ano: 	2019	
Palavras-chave: 	Estrus induction; Fertility; Reproductive efficiency; Economic return; Pregnancy rate.	
Resumo: 	Abstract The present study evaluates the economic viability of puberty induction in nulliparous Bos taurus indicus Nellore breed heifers using an intravaginal device of fourth-use and melengestrol acetate (MGA®). The experiment was undertaken in the Nossa Senhora Aparecida Farm, Terenos city, Mato Grosso do Sul, Brazil, and was utilized a completely randomized experimental design in a 2 x 3 factorial scheme. Two age classes were included in the study, which were divided into 348 precocious (early-cycle) heifers, aging 16-18 months, weighting an average of 264.6 kg and 543 conventional-cycle heifers aging 24-26 months averaging 346.8 kg. The three treatments were as follows: control without the induction of follicle formation (treatment 1); treatment 2: induction with an intravaginal implant (intravaginal implantation with a fourth-use progesterone implant on Day 0, withdrawal on Day 12, and application of 1 ml of intramuscular estradiol cypionate [ECP®]); and treatment 3, 2.3 g of MGA® during 12 days with supplement followed by 1 ml of intramuscular ECP® at the end of the treatment. Heifers induced via implantation had a higher rate of ovarian activity (presence of corpus luteum) during the early cycle (63.8% animals) while the conventional cycle (72.4%). This effect influenced the frequency of early stage anestrus (56%). Among the treatments evaluated, 72% of control heifers had no ovarian activity (absence of corpus luteum). In the group with implant induction the conception rates were 65.5% and 62.4% in early and conventional-cycle females, respectively. Puberty induction in Nellore heifers provides a high economic return. The protocol revealed highest efficiency compared to the control group.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122019000300205	
Editor: 	Universidad Nacional de Colombia	
Relação: 	10.15446/acag.v68n3.66190	
Formato: 	text/html	
Fonte: 	Acta Agronómica  v.68 n.3 2019	
Fonte: 	info:eu-repo/semantics/openAccess