The milking herd consists of 40-50 cows.
Each cow produces about 20,000 pounds of milk per year. The butterfat content ranges from 4.2% to 6.0% depending on the cows’ diet and the time of year. Somatic Cell Count, a measure of milk quality, is usually below 100,000.
The cows at St. Brigid’s Farm consistently rank in the top 10 in the nation for Genomic Jersey Performance Index. Calculation of the GJPI includes DNA markers for health traits, milk, fat and protein production, fertility and longevity.
The milking cows go out to pasture for 9 months of the year. In the winter they are fed a diet that includes corn silage, vitamin and mineral fortified grains and free access to hay.
Cows are bred using artificial insemination. Sires are selected based on milk and components, Jersey Udder Index, strength and longevity. Gender selected semen is used on heifers with the highest genomic indices.
All animals are turned out to graze in early April about when the Purple Martins arrive. The fields at either end of the farm are assigned to steers and young stock. Cows are allocated the middle of the farm for easy access to the robot.
Each cow paddock is approximately 1â…“ acres. Using break wires, paddocks are subdivided into quarters, thirds or halves depending on the time of year, rest period and stocking density. The rest period ranges from 21 days to several months to maximize soil health and grass production. Permanent waterers are located in each paddock.