Colostrum Increases Calf Immunity

REDFIELD, Iowa (DTN) -- Day one of life for a calf includes many important events for its health, with proper colostrum ingestion at the top of the list.

Travis White, veterinarian and director of technical services for Saskatoon Colostrum Company, said during a recent webinar that antibody transfer from cow to calf only happens during ingestion of colostrum, and not from transfer across the placenta. "The antibodies are absorbed through the small intestine to the blood stream and provide local immunity to prevent intestinal and respiratory illness," White said. "This will protect the calf until they can develop their own immunity at about 18 days."

IMPORTANCE OF COLOSTRUM

White said the cow's colostrum not only provides immunity, but also nutrients, growth factors and hormones. Fresh colostrum is the only way for calves to absorb leukocytes for immunity. Absorption of these healthful benefits decreases the longer it is between birth and consumption. A calf gets the best absorption within the first two hours after birth -- 48%. This decreases to 30% if consumed six hours after birth, and delaying past that increases the chance of problems.

Health risks increase if colostrum isn't consumed and passive transfer doesn't occur. White said issues can occur with consumption when dealing with a first-calf heifer, poor teat or udder conformation, leaking colostrum before calving, or when a cow produces a very small volume of colostrum. Other factors include a nervous cow, poor mothering instincts, a slow or ill calf, and poor colostrum quality.

"Calves can have risk factors for absorption as well," he explained. "Dystocia can decrease absorption as compared to a normal birth down to 20%, as does delayed suckling, calves that are twins or have a low birth weight, difficulty breathing, weak calves, cold temperatures and heat stress."

These factors of low or no colostrum consumption can lead to reduced feed efficiency and performance, reduced milk production, increased morbidity, and even death.

COLOSTRUM NEEDED IN TIMELY MANNER

White said a cow's colostrum is always best for the calf, but when that's not an option, a replacer may be used. Colostrum from another cow won't give a calf the leukocytes to absorb in the same way. This typically happens with dystocia calves from a hard pull or C-section, calves that are slow to stand and suck, orphaned calves, twins, and severely energy depleted calves.

"Colostrum needs must be managed right," he said. "One of the biggest management factors with colostrum is feeding it quickly. Ideally within the first two hours. The longer the first colostrum feeding is delayed, we actually delay the colonization of beneficial gut bacteria."

This is more commonly delayed in the beef industry than in the dairy industry, where calves are fed more quickly. 31% of the time, beef calves have passive transfer failure, compared to 12% in dairy calves. The delay increases the chance these calves can be affected by viruses, making it important to prevent this problem.

Genetic differences are seen in milk production across different breeds, and poor nutrition can be a key indicator of low colostrum quality. Weather conditions including drought, cold and heat stress, can also lead to poor colostrum production.

"When we are dealing with hypothermic calves, it's important to get their suckle reflex to return before we deliver any colostrum or they won't absorb it like needed," he said. "So, we can give warm fluids or warm electrolytes to help warm from the inside out and then give the calf some colostrum by bottle or from the cow after they can suck again. We can see similar problems with heat stress."

Studies at the Meat Animal Research Center show calves that experience failure of passive transfer were 6.4 times more likely to become sick in the first 28 days of life, 3.2 times more likely to get sick prior to weaning and 5.4 times more likely to die prior to weaning. White identified these are significant risks. Additionally, these calves weighed 35 pounds lighter at weaning and their feed efficiency was significantly reduced too.

A newer Canadian study shows calves with passive transfer failure are 7.9 times more likely to be treated, 18.5 times more likely to have mortality, and weighed an average of 40 pounds less after a 205-day pre-weaning period. "When we think of cost effectiveness, proper colostrum consumption is at the top of the list," he said.

WHEN TO GIVE A REPLACEMENT

White said if a producer is unsure whether the calf received the proper amount of colostrum, replacements are available and can be fed when needed. Feeding whole bovine colostrum replacer can help with passive transfer. This would especially be common with dystocia calves, night-born calves who are slow to stand and suckle, orphaned calves, twins, genetically high-value calves, and severely energy depleted calves.

It is important to select a replacement colostrum with the right amount of IgG immunoglobulins. He said, over time and through research, it has been found that calves need to receive at least 300 grams of IgG, hopefully in their first eight hours. It can be harder to measure when a calf is sucking the cow, but when delivered through a bottle there should be 200 grams in the first two hours, followed by 100 grams six to eight hours later.

Knowing the calf needs 300 grams of IgG colostrum helps when giving colostrum replacer or supplementing if the producer thinks the calf hasn't received enough from the cow. White recommends when giving lower volumes to the calf, make the calf suck it from a bottle for proper absorption. If a larger volume is required, an esophageal feeding tube calf be used. The size of the calf can make a difference in knowing how much to feed. White says in general a 100-pound calf should be fed 5 liters maximum and a 70-pound calf should be fed 4 liters. If it's under 70 pounds, then 3 liters of colostrum can be given. "Essentially, a calf can receive up to 10% of its body weight as a feeding of colostrum," he said.

When feeding colostrum from a source other than the calf's mother, it's most important to read the label to be sure everything is present that is needed for the calf to thrive. Timely consumption is a key factor in ensuring passive immunity is successful.

Jennifer Carrico can be reached at jennifer.carrico@dtn.com

Follow her on social platform X @JennCattleGal.

(c) Copyright 2024 DTN, LLC. All rights reserved.