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Breeding Efficiency In Dairy Cattle From Artificial Insemination At Various Intervals Before And After Ovulation, George W. Trimberger
Breeding Efficiency In Dairy Cattle From Artificial Insemination At Various Intervals Before And After Ovulation, George W. Trimberger
Historical Research Bulletins of the Nebraska Agricultural Experiment Station
The length of estrus and the time of ovulation were determined for 46 heifers and 86 cows of the Ayrshire, Guernsey, Jersey, and Holstein breeds by testing for end of estrus and ovulation at 2-hour intervals. Services were given by artificial insemination at various intervals before and after ovulation to determine the influence of this factor on the rate of conception. No significant breed or seasonal differences were found for length of estrus and ovulation time after end of estrus among the four dairy breeds represented in the experiment.
Conception Rate In Dairy Cattle By Artificial Insemination At Various Stages Of Estrus, George W. Trimberger, H. P. Davis
Conception Rate In Dairy Cattle By Artificial Insemination At Various Stages Of Estrus, George W. Trimberger, H. P. Davis
Historical Research Bulletins of the Nebraska Agricultural Experiment Station
A breeding experiment with 295 dairy cows and heifers of the Jersey, Guernsey, Ayrshire, and Holstein breeds was conducted in the University of Nebraska dairy herd. The females were given artificial services at various stages of estrus to determine the effect of time of service upon conception. The results obtained indicate the potential benefits in higher percentage of conception in females bred during the middle of estrus, toward the end of estrus, and those bred in full heat and rebred in 24 hours. The latter is usually not very practical, especially in artificial breeding rings, but there are occasions when …