JORDAN, Minn. – With the costs of raising heifers increasing along with input prices, farmers are paying attention to the potential that comes out of their youngstock groups.
Local farmers gathered at a Vita Plus workshop Dec. 16, 2022, in Jordan to learn about winter calf care, data collecting and employee management, among other items.
Dr. Lucas Mitchell, a calf and heifer specialist with Vita Plus, presented information and studies regarding calf and heifer rearing and the effect it has on first-lactation milk production.
“First lactation heifers make up 30%-50% of most United States dairy herds,” Mitchell said. “First lactation sets the tone for future performance.”
Once heifers come into the barn after freshening, their job is to produce milk and in 70 days be ready for reproduction again. If a farmer is combatting problems from calving, improper growth or effects from weaning, milk production is affected as well as profitability.
“We can’t expect cows that bottom out during first lactation to come back and be a rockstar,” Mitchell said.
Mitchell said he refers to a heifer raising puzzle with four pieces. The frame of the puzzle is comprised of in utero care with data regarding heat stress and preweaning growth rate.     Mitchell said those two factors set a foundation for the rest of a heifer’s growth.
Inside the puzzle are the prepubertal period and freshening.
Mitchell used data from the University of Florida to showcase heat stress and the affects it has on calves longer down the line. The graphs should that cows experiencing heat stress after only receiving shade as a heat abatement practice gave birth to calves that grew slower and produced 11 pounds less milk than the cows provided shade, fans and sprinklers as heat abatement.
The same study looked at granddaughters of the cows that experienced heat stress during pregnancy and calving, and the granddaughter’s production was affected also.
“Dams that experience heat stress tend to not last as long in the herd,” Mitchell said. “The effects of heat stress are a generational problem.”
Mitchell said genetics are a factor in milk production but certain management practices can help the calf in achieving its highest genetic potential in production. Even if the first step toward a better lactation starts in utero, there are things farms can do in the preweaning period to ensure growth.
“The preweaning period tends to get a lot of attention,” Mitchell said. “A study from Cornell University compared average daily gain in the preweaning stage to pounds of milk in lactations. The bottom line was feed more milk, get more milk.”
Post-natal care of calves is vital to their ability to stay in the herd. Calves should receive quality colostrum within two hours after birth and additional colostrum 12 hours after birth.
“If we mess up the vital first few weeks of a calf’s life, that puts a stamp on her throughout production,” Mitchell said. “We want to raise problem-free heifers to be problem- free cows.”
Mitchell said if calves show signs of potential illness, the most effective treatment is electrolytes at the first sign of the calf showing abnormal behavior.
“As the number of days a calf spends sick in the first four months increases, first lactation milk production decreases,” Mitchell said. “It’s critical to get it taken care of quickly.”
Signs of abnormal behavior could be a droopy ear, slower eating and lower feed intake. Mitchell said the best way to treat problems before becoming a larger issue is by treating quickly and effectively; if needed, work with a veterinarian to help determine which antibiotics will be most effective for each challenge.
Mitchell said starter intake and milk intake go hand in hand. Starter helps form the rumen, and milk is the most concentrated form of energy for calves to consume. The trick with the two is finding balance.
“I like to say that there are two steps to raising a calf,” Mitchell said. “Step one is get them to be a ruminant. This means putting them on starter. Step two is getting them to use that rumen. This could mean introducing forages just before weaning and continuing to provide them through the prepubertal stage.”
The prepubertal stage, age 4 to 10 months, is often the forgotten stage, Mitchell said. These heifers do not require the intensive management compared to other growth stages.
Mitchell said data from Cornell University shows that 1.8 pounds to 2 pounds of average daily gain in young heifers was the most efficient.
“At that 1.8 pounds of gain per day, we are getting the additional milk in production, and we aren’t pushing additional feed into the calves bringing the cost of raising a heifer up,” he said. “That being said, spending an additional $50 during the preweaning phase could mean additional milk in the tank which is what pays the bills.”
At 12 months of age, heifers are breeding age, and the next step is to get them ready for their first lactation. Mitchell said the freshening stage is important to focus on, getting the heifers to their ideal frame size and weight.
This can be a delicate process, because pushing the heifers to gain weight too quickly or gaining too much weight will have negative effects on their transition into production.
“When cows calve in fat, we know when they are struggling, because they get ketosis or milk fever; heifers hide these problems better,” Mitchell said. “Ideally, we want heifers at 95% mature body height when they calve in. Otherwise, we are feeding to grow them while they are trying to produce milk.”
Mitchell said the economic benchmark for Holstein heifers to calve in is at 22-24 months of age. Heifers are almost full grown but are not sacrificing milk production.
“It’s important to remember that there are a lot of factors that can affect first-lactation milk production,” Mitchell said. “This data should be able to help you assess your heifer raising program and adjust it to benefit the future of your herd however you see fit.”