South African Journal of Animal Science
versão On-line ISSN 2221-4062
versão impressa ISSN 0375-1589
KRIDLI, R.T.; ABDULLAH, A.Y. e HUSEIN, M.Q.. The effect of breed type and lactation status on reproductive performance in Awassi ewes. S. Afr. j. anim. sci. [online]. 2009, vol.39, n.5, pp.15-18. ISSN 2221-4062.
This study was conducted to evaluate the effect of breed types and lactation status on reproductive performance of hormonally-treated Awassi ewes. A total of 282 ewes were treated with intravaginal progestagen sponges and equine chorionic gonadotropin. Ewes were mated with fertile rams following sponge removal. Lambing rate was similar between brown-and black-faced ewes, while the percentage of multiple births, fecundity and prolificacy were greater in black-faced ewes. Lambing rate and the percentage of multiple births were similar between lactating and dry ewes. Fecundity tended to be greater in lactating ewes, while prolificacy was similar regardless of lactation status. Results of the present study indicate that black-faced Awassi ewes respond better to hormonal treatment than brown-faced ewes while the lactation status does not appear to influence the ewes' response to hormonal treatment.
Palavras-chave : Awassi sheep; breed type; lactation; oestrus; lambing.