The Mechanism of Temporary Infertility in Ewes Grazing Oestrogenic Subterranean Clover Prior to and during Joining
نویسنده
چکیده
Ewes in which oestrus had been synchronised were artificially inseminated (at the second synchronised oestrus) 17 to 21 days after placement on plots containing either oestrogenic (Trifolium subterraneum L. c% Dinninup) or non oestrogenic pasture. A comparison of the reproductive performance indicated that grazing oestrogenic pasture prior to and during joining reduced the proportion of ewes in oestrus, the ovulation rate and the fertilization rate. Evidence presented suggested adverse effects on the rate of egg transport and the number of sperm reaching the site of fertilization. Effects on corpus luteum weights, and embryo mortality are also reported.
منابع مشابه
A Study of Reproductive Wastage among Commerical Sheep Flocks Grazing Oestrogenic Pastures in South Western Australia
Reproductive wastage was investigated over two seasons in ten Merino flocks grazing pastures based on oestrogenic subterranean clover. Only 65 percent of ewes were served during the first 16 days of joining. Ovulation rates were low, averaging 1.13. Fertilization rates (73%) were low when compared with flocks unaffected by oestrogenic pastures. Embryonic mortality varied considerably between pr...
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