Good news for Registered Jersey breeders! The Jersey breed remains first for Productive Life among the six dairy breeds based on USDA genetic summaries.
Data published by the USDA Animal Improvement Programs Laboratory show that for cows born in the years 1997 through 2001, Jerseys have the longest average productive life of 33.7 months, or 1,029 days. A total of 196,713 Jersey cows were included in the evaluations.
By comparison, the weighted average Productive Life for more than three million cows of the other five breeds, including Ayrshire, Brown Swiss, Guernsey, Holstein and Milking Shorthorn, and born in the same five-year period was 27.7 months, or 844 days. The difference in favor of Jerseys is 185 days, or six months of herd life.
The trait of Productive Life is defined as – time in the milking herd before removal by voluntary culling, involuntary culling, or death. Its evaluation combines information from direct longevity, measured by DHI data on calving dates, disposal dates, reasons for disposal and lactation lengths, with correlated traits.