Two Factors Important to Calf Survival
There are two very important factors to calf survival. The first factor is body temperature, and in my opinion the most important, because if body temperature is not maintained then the calf can not absorb what it needs from the second most important thing to survive, colostrum.
Often times when a calf has not nursed the first thing ranchers want to do is get colostrum in them. While this is VERY important, it is not more important than getting the calf warm. As a calf’s temperature decreases, it’s ability to absorb the antibodies from colostrum also decreases. Even if the calf is given colostrum via an esophogeal feeder, if it is cold stressed it will only absorb half of the antibodies that are needed to fight off pathogens from the environment.
Registering Temperature and Warm Box
When we have a cold stressed calf we go about treating that calf based on its rectal temperature. A rectal thermometer is fairly inexpensive, but one of the most important tools you can own when having calves! If the temperature is registering on a thermometer, but below normal (below 100 degrees F), then we use a calf warming box. Calf warming boxes can be costly, so for smaller operations I would suggest the floorboard of the truck, a small warm room in the house, or using warm towels and blankets.
Before purchasing our calf warming box we would bring the calf into our laundry room (small room), shut the doors to it and place a small heater to help get the temperature in the room up. We would make sure the heater wasn't right next to the calf, and in a safe place in case the calf got up and started moving around. We would then place all the towels we could in the dryer and turn the dryer on to help heat the small space, but to also give us warm towels to dry the calf. The calf would breathe in the warm air into its lungs, and we would warm up the outside of the calf by getting it nice and dry with the warm towels. Often times we would get the calf all dried off (not to be mistaken for washed off, do not wash a calf, you want to leave the amniotic fluid for mama, so she knows her baby when you return it) and warm, and the next morning wake up to a calf wondering through the house.
Another trick we still use and that is one of my favorite ways to warm a calf is placing the calf in the floorboard of the truck with the heater on. Again, many times we would come out to the truck and find a calf standing up once it had gotten all nice and warm. When you're grabbing a calf out of the field and bringing in to warm up, just leave it in the floorboard with the heat on!
If you do use a calf warming box, make sure it has a fan to provide air movement to avoid hot spots in the box. The box also needs to be well ventilated to wick off the excess moisture and to prevent carbon monoxide build up. Make sure to thoroughly clean between calves to prevent spreading unwanted pathogens.
Non-Registering Temperature and Water Bath
If a calf’s temperature is NOT registering on the thermometer then we use a warm water bath. “If the calf’s temperature is much below 95 degree F, the hot box or warm room won’t help enough, especially if the calf is already dry. The calf’s coat will actually insulate the cold in the same as it would heat if it’s core body temperature is too low, and no hot box will get them warm. For this reason we use a warm water bath.
Warming with warm water bath is a lot of work. The water needs to be between 100-105 degrees F at all times. It is very important that the calf is NOT warmed too quickly. It needs to be warmed gradually. The calf needs to be submerged in the water, and fresh warm water constantly reapplied. It’s important that the temperature of the calf is taken often to make sure he/she is not getting overheated. This process can take a few hours to get the calf completely warm, and its internal temperature 100 degrees F. Use warm towels from the dryer to dry the calf in addition to a blow-dryer to get the calf completely dry. Sometimes we’ll dry off with warm towels then place the calf in the calf warmer.
After the calf is completely dry and temperature is normal the calf needs colostrum! Timing is crucial. By the time you find a cold stressed calf, get it warmed up and start to think about feeding it colostrum your window for absorbing colostrum gas probably already began to close. A cold calf will lose its suck reflex but once warmed should get it back. If it has no suck reflex, will not nurse or take a bottle, tube! Warm colostrum will help a calf stay warm and maintain it’s body temperature, but it is also vital to receiving much needed antibodies to help fight off pathogens. When a calf receives inadequate colostrum they often times will fight scours and pneumonia.
Colostrum should be fed within 6 hrs and ideally within 1-2 hrs. Blood glucose also depletes 30-60 minutes after its born if it doesn't nurse. The calf needs the energy from the colostrum and subsequent feedings to maintain energy and body temperature. A cold stressed calf will need to be checked often to make sure this energy store are not being used up. One feeding energy store lasts about 4-6 hours. “We don’t give up and not feed colostrum just because we might be late getting it into the calf.” (Thomas, 2022, para. 4) The gut is “open” to receive antibodies from colostrum up to 24 hrs, but after just a few hours the amount absorbed starts to rapidly decrease.
***Disclaimer***The information provided is based on personal experience and research. Medical advice should be obtained by a licensed veterinarian. This is just a guide and does not in any way replace advice from a licensed veterinarian.
Thomas, H. S. (2015, January 29). What to do about cold stress in newborns. Canadian Cattelman. Retrieved January 25, 2023, from https://www.canadiancattlemen.ca/features/how-to-handle-cold-stress-in-newborn-calves/