Some Gaps in Our Knowledge of the Seasonal Variation in Reproductive Activity of Ewes of Merino and Related Breeds
نویسنده
چکیده
The behaviour was similar in the ewes of the two breeds. When rams were introduced among ewes in the late summer and autumn, mating always commenced immediately, and most ewes mated within the first three to four weeks. On some occasions when rams were introduced in the spring, there was a delay before mating began; on most other occasions the initial rate of mating was rather low and in most instances it was five to six weeks before most ewes had mated. In one instance many ewes failed to mate within the eight weeks the rams were present.
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