Data/hora: 29/05/2024 08:59:52

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