How crossbreeding strategy is improving resilience at California dairy

They use the top 5-10% of bulls in each breed and focus heavily on milk, fat, protein, fertility and longevity.

Sexed semen is used exclusively for the first two services. If cows return to heat after this one straw of conventional semen is used before they switch to Aberdeen-Angus genetics.

Conception to sexed semen is averaging 40%. Cows that don’t exhibit a natural heat within 55 days of calving are enrolled in a double Ovsynch programme. The herd averages 1.2 services per conception and a replacement rate of 27%.

The farm is divided into eight groups, each comprising approximately 210-230 cows, including a fresh-cow and heifer group. Cows in early lactation are housed in compost-bedded cubicles, while later-lactation animals move to open corrals bedded with maize stalks. 

Animals less than 130 days in milk are milked three times daily through a 30/30 GEA rapid exit parlour – the rest drop to twice-daily milking once they are confirmed pregnant.  

Yields are averaging 39 litres daily at 3.9% butterfat and 3.45% protein, with milk supplied to Hilmar Cheese. Cows calve year-round, and the herd’s calving interval is 392 days, with days in milk currently sitting at 157. 

Fans and water-soaking systems (triggered once temperatures reach 23 °C) keep cows cool. A flood-wash system that uses recycled wash water is used to keep alleyways clean. 

Feeding is tailored to the lactation stage, with six different rations formulated. Maize silage is the dominant ingredient, supplemented by alfalfa, cottonseed, canola, rapeseed and byproducts. “Feed accounts for 50% of our costs,” Kurt notes. “We grow 100% of our own wheat silage and half our corn, but the rest we purchase.”

Across both dairy farms and their 405-hectare cropping enterprise, the Hoekstras employ 33 people, mostly Hispanic workers. While immigration raids have caused concern in the farming community, Kurt hopes that federal exemptions for agricultural workers will remain in place.

Trade politics haven’t helped either. “Tariffs with Canada and Mexico hurt us—the cheese price dropped nearly 40 cents. It’s bounced back now,” says Kurt, who hopes Trump makes progress on a deal with China. 

Bird Flu has also been rife across the State and struck at Cross View in December 2024. “It swept through the whole herd. Production dropped from 38 kg to 18 kg. We saw abortions in late lactation and had to cull about 100 cows,” Kurt recalls. During the worst of it, they bred all cows to beef as fertility plummeted. Sick cows were treated with electrolytes and pain relief.

“At the time, we were still using sexed and conventional semen, but we served everything to beef for two months because cows were so stressed. “It took about six weeks to clear, and milk slowly started to recover. We’re still testing positive in a few animals, but numbers are low,” he adds.

Cows can only be moved if they have three negative tests, each one week apart, and lactating animals can only go to restricted markets with a permit. Despite this, herd fertility is rebounding — pregnancy rates have averaged 29% over the past four months.

Plans for the next year are to increase shade for animals housed in outdoor corals. Having expanded by 400 cows in the past two years without buying in, the Hoekstras are benefiting from being able to sell springers.

They say this good reproduction is being driven by crossbreeding and wouldn’t go back to pure Holsteins. “ProCROSS has helped us with better health, reproduction and survivability,” adds Kurt.

In the picture: ProCROSS cow daughter of VH Neptune, from Anders Nilsson's herd Skråmered in Sweden.