Alternative Methods for Synchronisation of Ewes in Spring Using the 'ram Effect'
نویسنده
چکیده
Spring is the season when the ovaries of most ewes are inactive but ovulation can be stimulated by the 'ram effect' or injection of PMSG (Oldham 1980). However ewes do not display oestrus when induced to ovulate by these techniques and the corpora lutea (CL) which subsequently develop are frequently abnormal unless the ewe has been primed beforehand by progesterone (Oldham et al. 1980). In the breeding season progesterone from the preceding cycle fulfils this priming role. In spring there are two strategies to provide the necessary priming with progesterone.
منابع مشابه
The effect of ram exposure previous to progestagen oestrus synchronization on corpus luteum function and fertility in crossbred ewes
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