by: Heather Smith Thomas

Colostrum is crucial for newborn calves, to provide instant energy and temporary immunity to help fight off diseases. Calves with failure of passive transfer (calves that don't receive or absorb adequate levels of antibodies from colostrum) are at greater risk for illness. Calves with failure of passive transfer have up to 6 times greater risk of death in the first three months of life.

Dr. Robert Callan, Colorado State University, says the best situation is colostrum from the calf's own mother, if possible. If not, fresh or frozen colostrum from another cow is next best. Choose a mature cow that has had several calves; she'll have higher quality colostrum than a first-calf heifer.

"Colostrum can be frozen for emergencies, and keeps very well in one-quart or one-gallon freezer bags without losing quality for at least six months or longer," he says. Collect some at the start of calving season and it will be fine for that year, or the next.

"Even if it's a year old, it will still be better than anything you can buy. The only thing you need to be careful about is defrosting frozen colostrum so you don't destroy antibody proteins with hot temperatures. It's best to put the package in a pan of warm water, but defrosting can be done carefully in a microwave if you make sure you don't overheat it," Callan explains.

"Some people get fresh colostrum from a local dairy, but it can contain pathogens that could be transmitted to the calf and your herd -- such as bovine leukemia virus (BLV), Johne's disease, salmonella, mycoplasma bovis and other mastitis pathogens. Bringing home colostrum from a dairy is just as risky as bringing in a new animal from that dairy," he says. Biosecurity on your farm will be compromised.

Commercial Colostrum Supplements And Replacers -- "A beef calf should receive at least 100 grams of immunoglobulin (antibodies) within the first 6 to 12 hours, but preferably the first two hours. Recent research shows that 130 to 200 grams of immunoglobulin is optimum. When you compare colostrum supplements and replacements on the market, they contain varying amounts of immunoglobulin,"he says.

"Look at the label. In general, products with less than 100 grams immunoblobulin per dose are marketed as supplements, and products with 100 grams or greater are marketed as colostrum replacers. The products with a greater amount of IgG usually cost more, but their value to the calf is worth the extra cost," he says.

Usually, the dried/powdered product is mixed with 1.5 to 2 liters of warm water. "One downside is that when you give that much to a beef calf he will be full and this may decrease his drive to nurse and bond with the dam; he may not want to nurse again for about 12 hours," says Callan.

Several studies have looked at administering colostrum supplements or replacers to calves that also nurse the dam. "In general, if the dam has satisfactory colostrum and the calf nurses vigorously, obtaining an adequate amount, there is little benefit to giving a colostrum supplement," he says.

There's some debate regarding products made from blood plasma versus the ones made from dried colostrum. "I think they both work, as long as they have an adequate amount of IgG. There are some differences in the type of immunoglobulin, but these are minor," says Callan.

"If you use a commercial colostrum product as a replacement for colostrum, have a veterinarian test the calf's blood two to four days later to see if he received adequate antibody levels. This is a simple test that measures total protein concentration in the blood, which correlates well with immunoglobulin transfer. You want to see a total protein concentration of at least 5 g/dl, with a goal of 5.5 g/dl or greater," he explains.

Geof Smith, DVM, PhD (College of Veterinary Medicine, North Carolina State University), says every beef producer should have a few bags of replacer on hand, just for emergencies. "It's a lot easier to keep a couple bags of replacer in the cabinet than to suddenly have to go looking for a source," he says.

"There is great variation in quality of products, however, and also variation in price. You usually get what you pay for. When using it as an emergency source, and only having a couple bags on hand, it makes sense to buy a good quality replacer that will do a good job," says Smith.

"I've done a lot of research on replacers; some of them seem to work fairly well and some don't. Colostrum replacers are intended to be fed instead of cow colostrum and as a rule would be much higher than colostrum supplements in terms of antibody concentration, at least 100 grams per dose," he says.

"In general there are two kinds of replacers. One is made from plasma. The company gets cattle blood from slaughterhouses and harvests the plasma. It's a blood-based (plasma) colostrum replacer. These types of products have been on and off the market over the years because of BSE. For awhile people thought we should ban all feeding of blood-based products, but these are considered zero risk for transmission of BSE because the organism that causes BSE lives only in the brain; we don't find it in the blood," says Smith.

"The colostrum replacers are an acellular product, meaning there's not even any cells in them; the manufacturers spin off the plasma and use it. In terms of disease risk, it would be very low. Also, they irradiate it, which would kill any bacteria or viruses." The radiation will kill the pathogens but does not harm the antibodies. Excessive heating is what destroys antibodies.

The other type of replacer is made from bovine colostrum purchased from dairies. "The companies make sure it is high quality and dry it into a powder and irradiate it to kill any pathogens. They contract with dairies and make sure the cows are properly vaccinated, to have antibodies against all the major diseases the calves might be exposed to," explains Smith.

When choosing a replacer, select one that has been tested and performs well. "What we found through research is that antibody level is not always the determining factor on how effective it is. We first tried to figure out how much antibody should be in a colostrum replacer, but we tested some replacers that had about 100 grams of IgG and worked fairly well and tested others with much higher levels of IgG (150 to 180 grams) that didn't work as well to protect the calves. So it's not as simple as just looking at the numbers," he says.

"There may be differences in absorption of the IgG by the calf. With some products the calves seem to absorb these fairly well, and others not so much. We don't know why, but it may be differences in the manufacturing of those products between companies. I recommend using a product that has been tested, that you know has worked," he says.

If the dam is old or thin, how do you know if her colostrum is good quality? "There are ways to determine this, by measuring density of the fluid," says Callan. "The more immunoglubulins in the colostrum, the higher the density will be," he explains. Thick, dense colostrum is generally of better quality than thin, watery colostrum, but you can't always tell by looking at it. You can check it with a colostrometer. These can be purchased relatively inexpensively, for about $20 to $30.      

"The cost of the colostrometer is cheaper than a bag of good quality colostrum replacer and will pay for itself in its first use," says Callan. If you have first calf heifers (that typically don't have as high-quality colostrum as a mature cow), you could check to see if their colostrum quality is adequate for their calves.

"This kind of testing is not foolproof, but gives you a reasonable estimate. If it measures low, you should give that calf another source of colostrum," he says.

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