Data/hora: 01/06/2024 15:30:09

Biblioteca(s): | Embrapa Caprinos e Ovinos.
Data corrente: | 13/10/2004
Data da última atualização: | 13/10/2004
Autoria: | REKIK, M.; LASSOUED, N.; YACOUBI, C.
Título: | Reproductive performances in ewe lambs of the Queue Fine de l'Ouest breed and their D'Man crosses following synchronisation.
Ano de publicação: | 2002
Fonte/Imprenta: | Small Ruminant Research, v.45, n. 1, p.75-78, 2002.
Idioma: | Inglês
Conteúdo: | ln order to study the reproductive response to a synchronising hormonal treatment, oestrus, fertility and litter size were compared among 44 Queue Fine de l'Ouest (QFO) ewe lambs and 44 D'Man x QFO contemporaries run in a single flock under natural grazing conditions. Within breed, animaIs were divided into two groups (balanced for live weight) of 22 ewes, each induced to breed at 9 months of age after being treated with intravaginal progestagen and 200 or 400 lU PMSG, respectively, in groups 1 or 2. Throughout the 45 days mating period, ewes in oestrus were mated by Noire de Thibar rams. The hormonal treatment was effective in inducing oestrus in over 90% of the ewes. At the induced ovulation, the breed and the dose of PMSG did not affect either the number of animaIs exhibiting oestrous behaviour, or allowing mating. After the mating period, breed had a sjgnificant effect on fertility, with lambing rates of 93 and 66% for ewes of the D'Man x QFO and QFO breeds, respectively. Breed also significantly affected the proportions of females lambing when conception occurred at the induced oestrus. Though not significant, ewe lambs of both breeds receiving 400 lU PMSG produced 16% more lambs than those treated with the lower dose of 200 lU. With a dose of 200 lU PMSG, ewe lambs of the D'Man x QFO breed tended to yield a higher litter size than the QFO contemporaries (1.2+ 0.40 ys. 1.1 + 0.26). Globally, the results showed that attempts to breed from ewe lambs of the D'Man x QFO breed under the conditions described here are likely to lead to more satisfactory conception rates than in the case of the autochthonous QFO breed.
Palavras-Chave: | Deficiência reprodutiva; PMSG; Sincronização.
Thesagro: | Fertilidade; Ovino; Performance; Reprodução Animal.
Categoria do assunto: | --
Registro original: | Embrapa Caprinos e Ovinos (CNPC)
Exemplares: | CNPC - (17166-1) - ADC - AP - -- -  -  - v.45,p.75 - DIS