engleski

The oestrus synchronization in ewes during anoestrus by the application of different hormonal treatements

The ewes follow seasonal reproductive pattern what in the climate conditions of Albania means that the sexual activity is manifested from August to February. We assessed the efficiency of two hormonal protocols for the oestrus synchronization in ewes out of sexual season (during the May). For this reason two experimental groups, each comprised of 12 autochtonous Ruda breed ewes, are formed. The both groups had the same breeding and physiological status (cca. 60 days after the lambing). The treatment for the first group was comprised of vaginal sponge insertion (Fluor Geston Acetate, 40 mg) for 14 days and the 500 iu of eCG (equine Chorionic Gonadotrophin) i/m were applied at the time of vaginal sponge removal. The second group followed the similar protocol, but were additionally treated with 0, 1 mg/ewe GnRH (Fertagyl) 36h after the eCG application. The oestrus was detected by presentation of the ewes to ram 48h after vaginal device was removed. The presented ewes were mated twice in the interval of 12 hours. The oestrus detection and lambing rate were determined for each group. The oestrus was detected in 11 out of 12 ewes in each group (91%). The lambing rate in the first group was 1.81± ; ; ; 0.12 and 2.36± ; ; ; 0.51 for the second group (P<0.05). The hormonal treatment of ewes during anoestrus is efficient and economically reasonable particularly when GnRH was included in the protocol.

synchronization; oestrus detection; lambing rate; seasonality

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