Editor’s note: This article was written by Neil Broadwater, University of Minnesota dairy extension educator.
Dairy calves require a minimum of 150 grams of immunoglobulin-G (IgG) within 12 hours of birth to develop adequate immunity. Newborn calves need these immunoglobulins to fight off disease. This can be accomplished as follows:
- For calves over 100 pounds, feed 4 quarts at birth, 2 quarts at 12 hours.
- For calves between 50 and 100 pounds, feed 3 quarts at birth, 2 quarts at 12 hours .
Getting colostrum into the newborn calf quickly is important because the ability of the gut walls to absorb immunoglobulins decreases dramatically — by one third within six hours, and by 24 hours, the walls absorb less than 10 percent of what could originally be absorbed. However, this does vary somewhat from calf to calf. A fresh cow needs to be milked as quickly after calving as possible to get maximum immunoglobulin concentration in the colostrum. Because of variability between cows, all colostrum should be tested to determine its quality. A colostrometer can be purchased to check colostrum quality right on the farm.
In raising calves, many times it’s a fine line between them being healthy and getting sick. It’s a delicate balance of the calf’s ability to fight off disease versus the number of disease-causing pathogens to which the calf is exposed. Just a slight tip one way or the other can make the difference. A big factor that determines the health status of a calf is the environment into which it is born. In a dirty, wet, or high pathogen infested environment, even the best colostrum may not protect the calf from pathogenic attack.
One of the real challenges in managing the newborn calf is providing clean colostrum. The cow may provide high-quality bacteria-free colostrum, but is that what the calf is receiving? Several studies have shown that much of the colostrum fed to newborn calves contains large numbers of bacteria and many potential pathogens. As a result, calves can experience ‘failure of passive transfer’ (blood IgG level of less than 10 mg/ml at 24 to 48 hours after birth). They are more likely to become sick or die in the first two months of life than calves with adequate immunity. Much of the problem is associated with storing and handling.
Sandra Godden, of the University of Minnesota School of Veterinary Medicine, and Sheila McGuirk, of the University of Wisconsin School of Veterinary Medicine, have developed recommendations on delivering healthy colostrum to calves based on their individual research. Some of the major ones listed in publications and given in presentations include:
- Use good udder preparation so colostrum can be collected from a clean, dry udder.
- All equipment used to collect, store and feed colostrum, including calf bottles and nipples, should be cleaned and sanitized after every use.
- Discard colostrum from high-risk cows known to be Johnes-positive. Also, cows with Strep ag, Staph aureus or other environmental mastitis, can increase the level of bacterial contamination of colostrum.
- If not fed within one to two hours of collection, refrigerate colostrum for up to 48 hours. Beyond that, freeze it. Don’t store colostrum at room temperature, even for a short time, as bacterial populations multiply rapidly.
- Using a potassium sorbate preservative may stretch the refrigerated life to 96 hours.
- Freeze and store colostrum in small amounts (1- or 2-quart bottles or 1-gallon plastic bags) for rapid cooling/freezing and warming/thawing). Storing at -20 degrees F to -5 degrees F may allow for keeping it up to one year. Using larger storage containers means a slower cooling and thawing process, which allows for rapid growth of bacteria.
- Thaw frozen colostrum at 140 degrees F or less to avoid overheating and denaturation of immunoglobulins.
- Calves absorb immunoglobulins better when the temperature of the colostrum is close to their own body temperature of 101 degrees F.
Would pasteurizing colostrum eliminate pathogens? Research at Minnesota and Penn State has found that pasteurized colostrum had lower bacteria concentrations, and calves fed the pasteurized colostrum had more efficiency of IgG absorption at 24 hours from birth than raw colostrum. Optimum pasteurizing time and temperature to reduce bacteria counts without affecting colostrum IgG levels or viscosity is 140 degrees F for 30 minutes. However, this process won’t necessarily destroy all bacteria, as some will probably survive the process, especially if colostrum already has a very high concentration of bacteria. Careful handling of post-pasteurized colostrum is a must to prevent bacterial re-contamination.
In conclusion, determine how colostrum handling and storing practices take place on your farm. Then establish protocols for everyone involved in the calf operation. Be sure the protocols are followed every day, every feeding, so your newborn calves receive a high quality colostrum and on time. It’s what they deserve — a fighting chance to survive and thrive.
Source: University of Minnesota Extension