Ewe Genotype Effects on Seasonality of Oestrus and Ovulation in South-western Victoria
نویسندگان
چکیده
Two experiments, one examining oestrus and ovarian activity in 5 genotypes of young ewes exposed continuously to teaser rams and the other examining the onset of the breeding season in 4 separate strains of young Merino ewes, were carried out at Hamilton. In each experiment there were genetic differences in the duration of the non-breeding season. In experiment 1, Merinos and Comebacks had a shorter and less intense anoestrus season than Corriedales, Romney Corriedale cross and Border Corriedale cross ewes. In experiment 2, South Australian strain 3 had an earlier onset and Peppin strain 1 a later onset of the breeding season than Western District strain 1 or South Australian strain 1 ewes.
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