Data/hora: 23/06/2024 01:00:59

Biblioteca(s): | Embrapa Caprinos e Ovinos.
Data corrente: | 06/02/2004
Data da última atualização: | 28/08/2023
Autoria: | WINDSOR, D. P.
Título: | Variation between ejaculates in the fertility of frozen ram semen used for cervical insemination of Merino ewes.
Ano de publicação: | 1997
Fonte/Imprenta: | Animal Reproduction Science, v. 47, n. 112, p. 21-29, 1997.
Idioma: | Inglês
Conteúdo: | Two field experiments were conducted to investigate the amount of variation between rams, and between ejaculates within rams, in the fertility of frozen--thawed semen used for cervical insemination. Individual ejaculates from seven Merino rams were frozen and used to cervically inserninate Merino ewes at a synchronized oestrus at two sites. ln Experiment 1 (N = 491). pregnancy rates (deterrnined 70-80days after insernination) for individual rams ranged from 1.8 to 11,9%. Individual ejaculates produced pregnancy rates between 0 and 21.4%. Overall conception rate was 6.5%. No significant differences were detected. Pregnancy rates for the same rarns in Experiment 2 (N = 449) varied from 10.3 to 32.6% (P < 0.05). Ejaculate pregnancy rates ranged between 0 and 60% (P < 0.01). Fertility of individual ejaculates within rarns differed for three of the seven rams used (P < 0.01). It is concluded that considerable variation in fertility of frozen rarn semen exists between ejaculates within rarns as weIl as between rarns. Possible sources (biological and arising from freezing artefacts) of such variation and their practical implications are discussed.
Palavras-Chave: | Semen preservation.
Thesaurus Nal: | Artificial insemination; Cervix; Cryopreservation; Estrus synchronization; Males; Physiology; Pregnancy rate; Reproduction; Sheep; Spermatozoa.
Categoria do assunto: | L Ciência Animal e Produtos de Origem Animal
Registro original: | Embrapa Caprinos e Ovinos (CNPC)
Exemplares: | CNPC - (16709-1) - ADD - AP - DD -  -  -  - DIS