Now let’s get our calves ready for winter weather
As predicted in a previous article published here, Texas finished the year 2021 barely surpassing New York state in milk production (Figure 1). Challenges for the beginning of 2022 include significant increases in feed costs, farming input costs and labor shortage, to name a few. In addition, winter is a challenging season that requires additional effort from dairy farmers and personnel to manage their cows during cold weather conditions. An age group that deserves particular attention when temperatures drop are newborn calves. This article will cover the effects and importance of preventing cold stress in newborn calves.
Dairy farmers and personnel know winter brings significant challenges. They need to prevent and face issues like equipment not working properly due to freezing temperatures, slippery alleyways and frozen water troughs. Extreme weather conditions, such as winter storms like Goliath in December 2015 and Uri in February 2021 aggravate the challenges with cold stress and pose new ones. In the Texas Panhandle, dairy farmers make sure they reinforce existing wind breaks to protect their cattle (e.g., by piling up square bales of hay as protection from the north wind), feed extra the day prior to the storm, etc. The most sensitive age group that requires particular attention are newborn calves.
When do calves experience cold stress?
Calves are much more vulnerable to cold stress than cows. To put it in perspective, a lactating dairy cow producing about 66 pounds of fat-corrected milk may start experiencing cold stress roughly at minus 16 degrees (range negative 35 to 3 degrees) while calves might start experiencing cold stress in temperatures at 59 degrees . However, wind speed, ambient humidity and calf factors may change this threshold. Newborn calves are soaked in fetal fluids after calving, which increases body heat losses and makes them particularly vulnerable to cold stress and hypothermia during the winter season.
What are the consequences of cold stress?
Cold stress in newborn calves significantly delays the onset and decreases the rate of absorption of immunoglobulins (antibodies) after colostrum feeding5 . In cases of severe hypothermia, when the body temperature significantly drops, death may occur. Calves generate heat by increasing their metabolism and shivering, and conserve heat by reducing skin blood flow and piloerection to restrict heat transfer to the environment. Particular attention should be given to calves that had difficult births, as they have impaired mechanisms to maintain body temperature compared to calves from uncomplicated births6 .
What are the best management practices for newborn calves born in winter?
Checking pre-fresh pens frequently is paramount during the winter, and this frequency needs to be increased in severe weather events to limit a newborn calf’s exposure to cold temperatures. If possible, bringing cows that are close to labor to maternity facilities would allow personnel to more quickly dry off and warm calves after calving, decreasing the risk of cold stress and hypothermia. Ensure that your maternity employees have the right equipment, including winter clothes, PPE and utility tasks vehicles to transport calves. Once in the nursery area, feed the calves colostrum immediately. If a calf is reluctant to consume colostrum from a nipple bottle, tube feeding should be considered. Approximately one gallon of clean, quality colostrum should be delivered within one hour after calving. Colostrum will contribute to heat production . Calves should be kept in a clean, warm and dry environment. The use of calf jackets or infrared lamps can create a warm microclimate .
Nursery facility designs vary depending on the dairy. Examples include completely enclosed constructions with insulated walls and heating system, to facilities not completely enclosed but that still provide protection from the wind and precipitations. Regardless of facility design, calves should have:
- Abundant, clean and dry straw bedding material.
- Protection from wind and precipitation.
- Provision of clean, warm and high-quality colostrum.
- Use of calf jackets and/or heat lamps should be considered.
References
1 Piñeiro, J.M. Will Texas become the #3 dairy state in the country? December 2021.
2 U.S. Department of Agriculture, National Agricultural Statistics Service. 2020 and 2021 monthly reports. Milk Production.
3 Kadzere, C.T., M.R. Murphy, N. Silanikove, and E. Maltz. 2002. Heat stress in lactating dairy cows: a review. Livest. Prod. Sci. 77:59–91.
4 Nonnecke, B.J., M.R. Foote, B.L. Miller, M. Fowler, T.E. Johnson, and R.L. Horst. 2009. Effects of chronic environmental cold on growth, health, and select metabolic and immunologic responses of preruminant calves. J. Dairy Sci. 92:6134–6143.
5 Olson, D.P., R.C. Bull, L.F. Woodard, and K.W. Kelley. 1981. Effects of maternal nutritional restriction and cold stress on young calves: absorption of colostral immunoglobulins. Am. J. Vet. Res. 42:876–880.
6 Vermorel M., Vernet J., Dardillat C., Saido, Demigne C, and Davicco M.J. 1989a. Energy metabolism and thermoregulation in the newborn calf. Effect of calving conditions. Can. J. Anim. Sci. 69: ll3-122
7 Vermorel M., Vernet J., Dardillat C., Saido, and Demigne C. 1989b. Energy metabolism and thermoregulation in the newborn calf; variations during the first day of life and differences between breeds. can. J. Anim. Sci. 69: 103-111.
8 Borderas, F.T., A.M.B. de Passillé, and J. Rushen. 2009. Temperatu
Editor’s Note: This article reproduced from Texas A&M AgriLife Extension’s Texas Dairy Matters with permission.
