Treat dairy calves as investment in the future of herds

RALEIGH, N.C. — Dairy calves are an investment in the future of the dairy operation and the treatment they receive early in life impacts their future milk production.

“We know that heifer survival rate is one of the key things that affect profitability of dairies, but we really need to focus not just on survival, but having calves free of disease that are growing well and reaching adequate body weights at weaning and calving,” said Geoffrey Smith, dairy technical services veterinarian at Zoetis Inc.

“Beef on dairy calves continue to bring high prices and probably will at least for the foreseeable future because we are short on beef nationwide,” said Smith during a Hoard’s Dairyman webinar sponsored by Zoetis. “The beef industry really wants these calves and that has been a good thing for extra revenue for dairies.”

However, for some dairy operations this has restructured the heifer pipeline.

“Years ago, we had farms that had too many heifers,” Smith said. “But the number of farms that have a surplus of heifers has really dwindled.”

As a result, purchasing dairy replacement heifers has become more difficult and expensive.

“Ten years ago, you could buy a heifer for less than $1,000, three years ago it was $1,800 to $1,900 and today I’ve heard numbers as high as $3,500 to $4,000,” Smith said.

“Because we are producing so many beef animals, this has restricted the ability for dairymen to make appropriate culling decisions because they don’t have enough heifers to take their spot,” he said. “If you need 50 heifers to calve each month, you probably have to produce 70 or 65.”

Calf health continues to be a problem on some farms with high mortality rates and significant rates of diarrhea and respiratory disease.

“We know respiratory disease is associated with future productivity — there is anywhere from a 500- to 1,200-pound decrease in the first lactation milk associated with pneumonia,” Smith said. “We also know that scours are not only the leading cause of calf death, but it becomes a significant risk factor for the development of pneumonia.”

After five or six days, scouring calves will be really skinny.

“Their immune system is not working very well because they are in a negative energy balance, so a week later those calves get pneumonia,” Smith said. “We need to focus on not only producing enough heifers, but making sure we prevent disease and we’re weaning properly grown and healthy calves with good lungs.”

A research study in Wisconsin divided dairy calves into two groups — calves that had been treated for respiratory disease during their first 60 days of life compared to herd mates who had not been treated for respiratory disease.

“They found calves that did not have pneumonia, about 85% of them made it into the lactating herd,” Smith said. “For the calves that had respiratory disease, only about 65% made it into the lactating herd.”

Researchers at the University of Guelph in Canada ultrasounded calves from three dairies to identify if they had lung consolidation.

“For calves that had consolidated lungs, they saw almost a 1,200-pound reduction in milk yield during the first lactation compared to the normal calves,” Smith said.

An economic study published in 2020 looked at several costs associated with sick calves that factored in lower growth rates, increased risk of mortality, cost to treat the animals, increased risk of culling and reduced milk production.

“The study found that the cost of respiratory disease in the first 120 days of life was about $300,” Smith said. “Prices have changed a lot since then, so the model was updated with current numbers, so it is closer to $400 now.”

“Every time we are treating one of these calves for pneumonia, that’s $400 worth of impact,” he said. “We need to put some thought into prevention, because even though the calves may be responding to treatment, there is a cost to the farm for those animals developing respiratory disease.”

Diarrhea is the leading cause of death in dairy calves, Smith said.

“There was a study published recently from Canada that said calves with scours had a weaning weight decrease of 33 pounds compared to their herd mates that didn’t have scours,” he said. “And certainly there is a cost of treatment.”

Day one calf care, Smith said, is huge to prevent calves from becoming sick.

“Cleanliness of the maternity environment and colostrum management needs to be a focus on dairy farms,” he said. “If calves are born in a dirty environment, really no matter what you do the rest of the way, you are going to struggle.”

Colostrum management is probably the most important aspect of raising calves, the veterinarian said.

“We want to make sure we get colostrum harvested from the cow as soon as possible because the antibody concentration in the colostrum starts dropping as soon as the cow calves,” Smith said.

“I would really like the colostrum to be harvested within one to two hours,” he said. “If you are waiting 12 to 14 hours for the cow to go through the parlor before you get her colostrum harvested, you are probably always going to have some degree of problem with passive transfer.”

Second, it is important to feed calves the colostrum as soon as possible.

“The efficiency of the calf’s gut to absorb antibodies drops about 4% per hour after birth,” Smith said. “At eight to 12 hours after a calf is born, it is not absorbing antibodies nearly as efficiently as it was when the calf was born, so we need to have a plan in place for getting the colostrum out of the cow and into the calf as quickly as we can.”

Dairymen must make sure the colostrum fed to calves is clean.

“We know that the bacteria in contaminated colostrum will compete in the gut with antibodies for absorption,” the veterinarian said. “So, not only can the bacteria make the calf sick, but they can lead to failure of passive transfer.”

Typically, dairymen feed three to four liters of colostrum to calves, Smith said, and ideally within two hours after birth.

“I encourage you to monitor some total proteins on occasion, even if it is once a month, on 10 calves to get an indication of the job you are doing with colostrum management,” he said.

New research has looked at feeding colostrum to calves beyond the first day of life.

“Most of the data has been really positive,” Smith said.

However, this may be difficult to accomplish on dairy farms because it means milking the cow through its fifth or sixth milking and keeping that milk separate from the regular milk.

“If you are a farm that is selling a lot of colostrum and your calf health is suffering, you might be better off feeding some of that colostrum instead of selling it,” the veterinarian said. “Think about if there is a way you could make this work.”

Smith would like dairymen to weigh their calves.

“This is probably the best way to access your nutrition program if you have a birth and weaning weight,” he said. “It would be good for the average daily gain to be in the 1.5 to 1.6 range and very good is 1.7 to 1.8.”

Weighing calves is not fun, Smith said.

“You don’t have to weigh every calf, but I think we should do it at least quarterly to see what individual average gains are,” he said.

“If we are going to spend time and money getting these calves started right, we need to make sure they continue on that positive plane of energy after weaning,” the veterinarian said. “The goal is to have heifers at 85% of their body weight when they calve and a lot of farms are not growing their heifers appropriately.”