July 25, 2021

Colostrum improves immune system of calves, increases milk production

NEW PRAGUE, Minn. — Colostrum provides protection for dairy calves against bovine respiratory disease.

Timing and volume are the most important factors for feeding colostrum to newborn calves.

“Colostrum is wonderful stuff and we want to feed as much as we can as fast as possible,” said Lowell Midla, veterinarian and member of the cattle technical services team at Merck Animal Health. “It is never too early to give colostrum.”

Midla, who spoke during a webinar hosted by the Dairy Calf and Heifer Association, discussed the disease triangle.

“Veterinarians tend to focus way too much on the bug when the host and environment are just as important,” he said. “If a calf is colostrum deficient, even a minor challenge with a few bugs is able to overcome that host.”

Robust calves that have consumed lots of colostrum also can have problems.

“If we stuff 100 calves in a chicken coop, even a minor challenge is going to cause disease,” Midla said.

Studies show the importance of colostrum for calf health.

“There are about 15 studies that show if you feed calves more than 2 quarts of colostrum twice a day they will make more milk during the first lactation,” Midla said. “Part of that increased milk is due to the fact those animals are healthier.”

The immune function of calves requires energy.

“When we feed them adequately we’re giving them adequate energy for their immune system to respond to challenges,” Midla said.

Proper ventilation helps prevent BRD and dairymen should measure the air exchanges per hour or the frequency of all the air under a roof that gets moved out and new air comes in.

“You can get almost anyone to put up a tube, but there is a difference between putting up a tube versus tube ventilating a barn,” Midla said.

Stocking density of a calf barn is important for calf health.

“Penn State recommends at least 30 square feet per calf for calves less than four months of age,” Midla said. “But more is better in group housed situations.”

Midla recommends filling pen of calves in a short period of time.

“Less than one week per pen to fill a group is the best,” he said. “It is a good idea to house the calves in hutches initially and wait until they are two weeks of age before you move them into the group housing.”

Dairymen should not just turn the automatic feeders on and forget about them.

“You must monitor the total solids coming out of the nipples to make sure it is correct,” Midla said. “The total solids should be consistent in the 13% to 15% range.”

The veterinarian reminded dairymen about maternal antibody interference that lasts for about three months after the calf is born.

“The antibodies the calf gets through the colostrum from mom is going to bind to a vaccine prior to the vaccine stimulating an immune response and prevents the vaccine from being effective,” Midla said.

“Intranasal vaccines go around that because there are no antibodies from mom in the nose,” he said. “You can vaccinate against bovine viral diarrhea in the face of maternal antibody interference.”

BVD is always changing and mutating, the veterinarian said.

“About 80% of the success of a vaccine is getting it out of the refrigerator and giving it to the animal,” he said.

Midla encourages dairymen to work with their veterinarian to decide to control a BVD problem on a farm or to get it out and keep it out of the herd.

“BVD is a disease where biosecurity matters,” Midla said.

“For heifer raisers I encourage you to require testing prior to arrival,” he said. “If there’s a persistently infected calf inside one of those heifers and you send it home to an operation that doesn’t have BVD, that’s a problem.”

Cows can be vaccinated for bovine respiratory disease prior to calving.

“These three studies show that giving a BRD vaccine to the dam pre-calving had a protective effect and the herds had less risk of BRD in their calves,” Midla said.

“On an ideal dairy, we need to give one dose of intranasal vaccine prior to weaning or co-mingling of calves at 60 days of age,” he said. “You shouldn’t have BRD at less than 60 days of age, but when you co-mingle calves, there is a risk for pneumonia.”

It is important for dairymen to keep good records for the day of age when calves become infected with BRD.

“If we’re going to use a vaccination as a tool to prevent it, it has to be done prior to the event,” Midla said.

All dairymen should develop a treatment protocol for BRD.

“Have a protocol for the antibiotic to use for first line therapy and use it for every calf, every time,” Midla said. “If the first treatment isn’t working, switch your protocol, but have a protocol and stick with it.”

Martha Blum

Field Editor