New Details on Colostrum
contributed article by Dr. Vince Collison, Collison Embryo and Veterinary Services,
Rockwell City, Iowa
I recently watched a webinar put on by Colostrx, which is a subsidiary of the Saskatoon Colostrum Company. As we approach a new calving season, there was a lot of information in this webinar which is relevant for the upcoming calving season. The main take away from this information is how important it is to intervene when a calf has any issues with nursing in the first few hours of life.
Colostrum Absorption Rates
Typically, we think we have 24 hours to get colostrum into a newborn calf, but a graph displayed during the Colostrx webinar showed that in the first two hours is when the calf has the maximum absorption of colostrum. At this point, it is at about a 48 percent absorption rate.
From two to four hours after birth the absorption rate slightly drops off to about 45 percent. Starting at four to seven hours after birth, the rate of absorption falls off quickly to 20 percent. So, by seven hours post birth the absorption rate of colostrum is cut to less than half of what it is in the first four hours of life.
From seven hours to 22 hours the absorption rate gradually declines from 20 percent to 10 percent. At 22 hours to 24 hours the ability to absorb colostrum drops off abruptly from 10 percent to 0 percent. This graph really emphasizes how small a window of time we have to make the biggest impact if we have a situation where we need to intervene.
The other point that was made is that colostrum absorption is reduced by about 35 percent whenever there is a dystocia (difficult birth). This makes it even more critical to intervene early whenever you have a calf that had to be pulled because of calving issues.
Failure of Passive Transfer
Whenever a calf does not absorb enough colostrum, it results in a condition called Failure of Passive Transfer (FPT). FPT is defined as having less than 10 grams/liter of IgG immunoglobulins in the blood stream. The rate of FPT within a herd is probably variable but has been reported to be as high as 31 percent. In the webinar, they presented a study conducted by the USDA Experiment Station in Clay Center, Neb. where they measured the effects of FPT in calves.
What they found is that calves affected by FPT were:
1) 6.4 times the risk of sickness in the first 28 days of life
2) 3.2 times the risk of sickness prior to weaning
3) 5.4 times the risk of death prior to weaning
4) Had a 35-pound lower weaning weight
5) Calves grow at 2/3 of the growth rate of calves with adequate passive transfer
6) In the first 6 months, feed efficiency can be reduced by up to 50 percent
Another study presented that was done in Canada, showed similar results, but showed an even higher risk of death prior to weaning at 18.5 times more in FPT calves.
FPT Prevention
While FPT is defined as IgG levels of less than 10 grams/liter in the blood, to achieve excellent passive transfer the calf should have IgG levels of 25 grams/liter in the blood stream.
To prevent FPT we need to make sure calves are nursing well within the first two to three hours of life. If they are not nursing on their own, we need to intervene and ensure they are getting what the need by helping them nurse the cow or tube them with colostrum. Calves will need to take in 200 to 300 grams of IgG via colostrum to be sure that they achieve adequate passive transfer.
If you cannot get the calf to nurse the cow, it is probably better if you can get the calf to nurse a bottle of colostrum rather than tube them. By nursing the bottle, the colostrum will go directly to the abomasum and give the most efficient use of the colostrum by the calf. When you tube a calf, much of the liquid will go to the rumen before it spills over to the abomasum. This will also work but may require more volume to get the same effect as nursing.
Thermoregulation
Another benefit of colostrum is its ability to help the calf with thermoregulation. The primary way that calves maintain their body temperature in cold weather is from brown fat. The brown fat is loaded with mitochondria that provide the energy needed to keep their body temperature high during cold weather. For brown fat to work properly, it needs to be activated from the fat in colostrum.
The thermoneutral zone for calves is 55 to 79 degrees Fahrenheit. So, it’s very important to have brown fat fully activated anytime the temperatures drop below 55 degrees Fahrenheit, which is pretty frequent during calving in the Midwest. Calves that take in enough fat via colostrum are more active, have higher performance, less death loss, and reduction of illness.
Additional Benefits
Besides the benefits from the antibodies and fats in colostrum, there are many other things that make colostrum important. There are many growth factors present in colostrum, and it is a good source of vitamin A.
Also, colostrum aids in the growth of beneficial bacteria in the calf’s gastrointestinal tract. Proper colonization of the gut is important for normal digestion and acts as part of the calf’s defense mechanism against disease. All of these things play a role in the calf’s overall wellbeing for the first couple months of life.
I always feel that less is more when it comes to bovine health. I’m not implying that vaccines are not necessary to manage herd health, but in order to keep programs simple we need to take advantage of naturally occurring benefits like colostrum intake at birth.
Most beef cows will have good quality colostrum, provided they are getting what they need nutritionally and are properly vaccinated prior to calving. But if we do have to intervene, it’s nice to have options that increase convenience during times when we don’t have the time to catch a cow and milk her out or maybe don’t have the facilities available to restrain the cow properly to help the calf nurse or milk her out.
learn more www.collisonembryoservices.com
Dr. Vince Collison is co-owner of Collison Embryo and Veterinary Services PAC
in Rockwell City, Iowa.
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