The most important meal of a calf’s life is its first. Colostrum serves as a loan of immunity from its mother until the calf has time to build its own, according to University of Nebraska veterinary epidemiologist Brian Vander Ley. Calves are born having “almost no antibodies,” but they have the ability to make them.
“Some of the immunity is short-lived, which makes it critically important, because if it doesn’t receive that passive transfer, it is without protection for about two weeks,” Vander Ley said, according to information provided by Certified Angus Beef.
Vander Ley shared his take at the 2019 Range Beef Cow Symposium last month in Mitchell, Neb., based on his ongoing work at the Great Plains Veterinary Educational Center in Clay Center, Neb.
Ensuring that cows are prepared to produce adequate colostrum is just as important as their calves receiving it, Vander Ley said. Body condition scores are the top indicators.
“Cows that are in good condition, at least a five, give birth more quickly,” Vander Ley said. “They make better colostrum, and their calves get up and nurse faster because they're stronger and tend to have better immune function.”
If a cow or heifer is experiencing dystocia, on the other hand, the chances of the newborn calf getting up and nursing decreases significantly.
“The longer a calf spends in anaerobic metabolism without oxygen, the lower its blood pH goes. So, it goes into acidosis,” Vander Ley said. “Acidosis in calves has the direct effect of depressing their brain function.”
If a cattle producer is going to assist with a delivery, “then you better go through the trouble” of making sure the calf gets colostrum, he said.
“If that calf isn't standing in a half-hour and nursing, then you better get its mother in the chute and milk her out,” he said, adding that it’s a missed opportunity to not guarantee that the calf receives colostrum.
While there is still absorptive capacity up to 24 hours, the most optimal time frame is four hours. After that, the calf's ability to absorb quickly declines.
Nursing is better than tubing. Calves have a reflex pathway called the esophageal groove. Whenever a calf nurses, the reflex response in its forestomach creates “a straight shot from the esophagus to the small intestine,” Vander Ley said. “If we tube, that doesn't happen. When we tube, we think it pools in their rumen or in that forestomach somewhere. Then they don't access all of it.”
Even nursing a bottle is preferred to tubing, if possible, although he acknowledged that not all calves are up for it. In that case, it’s better to get colostrum in the calf.
“One of my favorite sayings is, ‘Don't let perfect be the enemy of good.' This is a great example where to apply that,” Vander Ley said.
However, there are two things to avoid when tubing. One is tubing a calf on its side, where a bad event is much more likely to occur. Sit the calf up so its “sternal” side or chest is touching the ground.
The other error would be stretching out a calf’s neck so that the tip of the tube naturally wants to go into the trachea. Vander Ley suggested bending the calf’s head as much as 90 degrees to the right, which lets the tip of the tube bypass the trachea and go into the esophagus on the left side of the calf’s throat.
If it is suspected that a calf didn’t nurse enough or soon enough and the window for absorption is closing, Vander Ley said it’s better to give it the whole dose of colostrum rather than just a “boost.”
“Because of gut closure, if we create any kind of satiety in calves, they don’t feel like they have to get up and nurse, and we’re going to miss that opportunity pretty quickly. It makes me feel a lot better to get that calf a full dose immediately,” he said, noting the satisfaction of doing everything possible.
If that means tubing a calf, it's preferable to do this with its mother’s colostrum, because “she makes as close to perfect antibodies that her calf needs,” Vander Ley said.
If the milk can't come from the cow, replacer products are better than supplements, Vander Ley said. Replacer is made from dried colostrum from dairy cows, while supplements are often “spray-dried bovine plasma from slaughter plants.” Both have useable antibodies, but replacers contain more and are from analogous origins.
Read the label of replacer products to make sure the calf is given an adequate amount, he said. Most products recommend 100-120 g of antibody for adequate passive transfer, but that can take two packages of a colostrum replacer.
Vander Ley pointed out that dairy industry research has found that calves that don’t get enough passive transfer have more preweaning problems like scours and infections. Other data suggest that respiratory disease becomes a greater problem at the feedyard.
Vander Ley concluded that the issues are complicated, but management is simple: Feed the spring-calving herd well throughout the winter. Make a plan for when calving starts so you know what you’re going to do. Have products and tools available.
Four hours will come and go quickly for each calf, but those are the windows that get the calves off to the right start.