Data/hora: 15/06/2024 05:00:26

Biblioteca(s): 	Embrapa Caprinos e Ovinos.	
Data corrente: 	23/03/2005	
Data da última atualização: 	23/03/2005	
Autoria: 	HILL, J. R.; THOMPSON, J. A.; PERKINS, N. R.	
Título: 	Factors affecting pregnancy rates following laparoscopic insemination of 28,447 merino under commercial conditions: a survey.	
Ano de publicação: 	1998	
Fonte/Imprenta: 	Theriogenology, v. 49, n. 4, p. 694-709, 1998.	
Idioma: 	Inglês	
Conteúdo: 	The results of laparoscopic insemination of 28,447 Australian Merino ewes with semen from 468 rams were used to study factors influencing pregnancy. The overall pregnancy rate was 71.7% (20,423/28,447). Pregnancy rates varied with type of progestagen implant, type and dosage of PMSG, fresh or frozen semen, wool type and number of ewes inseminated per hour. The pregnancy rate (64.6%) obtained with Medroxy-progesterone acetate (MAP) sponges  was significantly (P < 0.01) lower than with Fluorogestone acetate 30 mg (FGA 30; 74.7%) sponges, Fluorogestone acetate 40 mg (FGA 40; 72.1 %) sponges, and Controlled Internal Drug Release (CIDR-G ; 71.7%) implants. A PMSG dose of 200 UI resulted in significant1y (P < 0.05) lower pregnancy rates (62.4%) compared with 250 lU (72.9%),300 lU (79.1 %) and ³375 IU (69.4%). The mean pregnancy rate for ewes administered Folligon PMSG was 71.9%, which was significantly higher (P<0.001) than that of ewes treated with Pregnecol PMSG (65.8%). The use of Pregnecol PMSG and MAP sponges was associated, and thus their conditional effects could not be calculated. Ewes inseminated with fresh semen were significantly (P < 0.001) more likely to become pregnant (82.2%) than those inseminated with semen frozen in pellets (69.5%) or straws (71.6%). Ewes inseminated during the months of March, April or May (falI, 71.5%) were just as likely to become pregnant as those ewes inseminated in November, December, January or February (69.6%). Significantly (P < 0.05) fewer strong wool ewes become pregnant to laparoscopic AI, (67.6%) than fine (71.7%), [me medium (73%) or medium wool ewes. Significantly (P < 0.0001) more pregnancies (77.6%) were achieved when more than 55 ewes were inseminated per hour compared with fewer than 35 ewes per hour (63.4%). 	
Palavras-Chave: 	Teste de prenhez.	
Thesagro: 	Inseminação Artificial; Laparoscopia; Ovelha; Ovino; Reprodução Animal.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Caprinos e Ovinos (CNPC)	
Exemplares: 	CNPC - (17545-1) - ADC - AP - -- -  -  - v.49,p.697 - DIS