Journal of Dairy Science · 1959 · 37 citations · 15 references
Social SciencesAgricultural EconomicsForage ProductionReproductive DemographyResource Utilization AnalysisBirth IntervalsResource Utilization EstimationConception TimingService Duration
The interval from first service to conception decreases as the service interval increases from 0 to 127 days, at which it reaches a minimum. After a service interval of 127 days, the interval from first service to conception increases slightly as the service interval increases. The length of the service interval accounts for only 1.4% of the variance of the interval from first service to conception; thus, even though its effect on the interval from first service to conception is significant, its effect is small and of little importance.
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Causes of variation in milk and butterfat yield of dairy cows.
I. Johansson, A. Hansson · 1940 · 107 citations