Importance of Colostrum for Calves
By Heather Smith Thomas
Newborn calves need colostrum to help protect them from diseases they face in the first weeks of life. Unlike human babies that obtain mother’s antibodies via mother’s bloodstream and placenta, ruminants are born with a naïve immune system. Dr. Travis White, Director of Veterinary Services, SCCL (Saskatoon Colostrum Company Limited) explains that ruminants are unique.
“Because of the type of placenta in the dam, the fetus can’t absorb any antibodies from her blood. Newborns require colostrum, consumed orally. That’s the only way they get any immunity.” This provides passive immunity for a few weeks until their own immune system develops.
The sooner the calf ingests colostrum, the better. “It’s a race against time. Years ago people thought calves had 24 hours to obtain antibodies, but studies showed the highest absorption of IgG within the first 2 hours. By 6 hours, calves have lost about half the absorptive capacity of the gut,” he says. Gut closure (preventing large molecules like antibodies to go through into the blood and lymph systems) begins soon after birth.
“By the time the calf is 12 hours old, capacity has dropped to about 15% so it’s a race against the clock.” It’s also a race between the antibodies and pathogens; if the calf nuzzles a dirty flank, he may ingest pathogens before he nurses colostrum. If he gets too cold or can’t get onto a teat, this delay can make him vulnerable to disease.
The consequences of a calf that doesn’t receive adequate colostrum or receive it soon enough can impact future health and performance. “Numerous studies have looked at this. If the calf didn’t get adequate colostrum (failure of passive transfer), he is 3.5 to 9.5 times more likely to become sick prior to weaning—with scours or pneumonia. These calves are 5.5 times more likely to die before weaning. Morbidity and mortality is much higher than in calves that get adequate colostrum,” says White.
Negative consequences go even farther. “Calves with failure of passive transfer have lower daily gains; their average daily gain is reduced by about one-third. They gain at about 2/3 the rate of their healthier cohort. Feed efficiency can be reduced by as much as 50%. If these are replacement heifers, their age at first service is extended by about 30 days. We must feed them 30 days longer to get to breeding weight,” he says.
“When you consider commodity prices and what it costs per day to grow a heifer, having an animal whose average daily gain and efficiency is reduced—and fed longer—becomes a significant economic factor.” It’s worthwhile to make sure each calf gets adequate colostrum (or supplement or replacement) on time. How can producers ensure that calves get colostrum, and when should they provide a supplement or replacement? If you are monitoring calving cows, it’s easier to know if newborns get up and suckle on time. You have a chance to intervene if necessary, as opposed to finding the pair in the pasture and not knowing how old the calf is.
“Our goal is that in the first two hours the calf is up and well bonded with the dam, nursing well. If he hasn’t nursed by then, we think about giving colostrum,” White says. We help the calf suckle, or milk out the dam and administer colostrum to the calf. Sometimes, however, that’s difficult or impossible and it’s best to provide a colostrum replacer product.
“Typically we’d start with a colostrum product that provides 100 grams of IgG. At the second check, about 6 to 8 hours later, we’d want to see that calf up and nursing the dam. If he’s not, he needs a second dose of colostrum,” says White.
“Another time to think about replacement is an orphan. Perhaps the dam dies, or we have to remove the calf from the dam for some reason, or a cow had twins and can’t raise them both and doesn’t have enough colostrum for both. A calf without mom needs two doses of colostrum as full replacement. If its twins we might leave with the cow, we may supplement both with colostrum to make sure they each get enough,” he says.
Stress decreases the newborn calf’s ability to absorb antibodies from colostrum. “If it was a difficult birth, extremely cold weather, or any other severe stress, ability to absorb colostrum drops by about 35%. Those calves need some additional colostrum,” says White. Sometimes a calf just needs supplemental colostrum rather than a replacer.
“Maybe the calf is weak; maybe it stood up and tried to nurse and obtained some colostrum but not enough. We need to get some energy and IgG into that calf, and may choose a supplemental dose,” he says.
Calves from first-calf heifers may benefit from colostrum supplement. “Studies have shown that about 33% of beef calves fail passive transfer. Some cows have poor quality colostrum or not enough, or a weather event or bad udder keeps the calf from nursing quickly.
About 70% of calves with inadequate passive transfer are from first-calf heifers. They may have lower quantity and not as many antibodies. Supplementing calves from first calf heifers can make a big difference in weight gain and health status.”
Most calves can be given colostrum via bottle if they have good suckle reflex, but some need tube feeding. “If it’s a supplemental dose, under 2 quarts, it’s better to bottle feed, if possible. For volumes over 2 quarts, studies show esophageal feeding is better for adequate absorption,” he says.
There is no substitute for monitoring the herd, knowing what’s happening as calves are born. “Some producers put cows through a barn and have cameras or check them routinely. If we can ensure that each calf is getting maternal colostrum within the first 2 hours, that’s ideal. But when things go awry, producers should get colostrum into those calves so they don’t suffer long-term health issues,” says White.
Select a good-quality colostrum. “We at Saskatoon Colostrum believe that Mother Nature has done a perfect job of developing colostrum for calves. Our colostrum is all whole bovine colostrum with nothing added and nothing taken away. It’s as close to Mother Nature as you can get. It’s an immune system in a bag—and will protect that calf and enable it to be productive throughout its life.”