Even though winter is halfway over, we are still in the midst of experiencing fluctuating temperatures (some of which are very, very cold). As I’m sure you’ve start prepared your homes and cars (and maybe even your bodies!) for the transition to cold temperatures, may you also consider adjusting your farm management programs to better suit your cows and calves winter needs. These 5 tips will help keep your calves and cows healthy and happy during the cold winter months.
- Recently, my understanding of the thermoneutral zone shifted. By definition, the thermoneutral zone is a given range of temperature where animals are able to regulate their body temperature to maintain core body processes. If the temperature either falls below or rises above this zone, animals enter a state of cold stress or heat stress, respectively. While listening to a webinar recently, Dr. Van Os provided a new way of thinking of thermal stress, and she suggested that while cows have a distinct zone for thermoneutrality, they may also have a zone of thermal comfort which is a much narrower range of temperatures that accounts for behavioral responses to temperature. Cold stress is not nearly talked about as much as heat stress for mature cows because they are able to generate heat through ruminal fermentation, but it is still important to recognize that they can experience cold stress the barn is drafty, if ventilation isn’t adequate or if stalls are dampened with snow/ice. Calves on the other hand, are pre-ruminants which means they don’t have the luxury of being able to generate body heat through rumination. It is very important to consider increasing their nutrition in the winter – when the temperature drops below the calf’s thermoneutral zone (which is between 59 and 77°C), she will experience cold stress. In order to combat cold stress, the calf must consume more nutrients and more energy, otherwise she will have to rely on her body reserves to keep her warm. For your older calves, this shouldn’t be a huge challenge – just make sure they have lots of solid feed in front of them. But for your younger calves that still rely on milk replacer or whole milk, making sure they have enough energy to meet their maintenance requirements and can also grow during these cold temperatures is a challenge. The most common strategy for increasing nutrient availability to calves during the winter is to add a third feeding. If you are already feeding three times a day, you can increase the volume of milk you’re offering, or switch to a different milk replacer that is higher in energy. For every degree drop below 50°F, energy requirements increase by 1%. Depending on your milk replacer and feeding rate, this can equate to a large additional energy requirement that is often overlooked. Please reach out if you need help calculating calf energy requirements and identifying a feeding program that works well for your herd.
- Calves get cold in the winter, just like us – providing them with a calf jacket is a good way to help keep them warm. Putting a calf jacket on can decrease the calf’s heat loss by 15% – which means more energy can be put to growth! Before you put a jacket on a newborn calf, make sure the calf is dried off well so that the jacket doesn’t trap in moisture and make her even colder. Lastly, not only is it important to provide the coat, but it is also important that the coats are washed frequently to minimize spread of disease.
- Water is just as important in the winter for both cows and calves! Water is the single most important nutrient for dairy cows as it plays an integral part in immune function, milk production, and overall health. Make sure to continually check water sources throughout the barn to make sure there is sufficient water supply. The FARM 4.0 update, requires calves to have access to water by 3 days of age – and yes, this includes in the winter. Water supply becomes increasingly important if you are increasing the amount of milk replacer you are feeding because you will consequently be increasing the overall solids level and this may cause calves to want to drink more water. Staying hydrated is not just an important part of calf health, but it can also help get calves on solid feed quicker which can improve weaning success and help achieve your target average daily gains. Replacing/checking on water supplies and making sure they stay clean (and not frozen) is one of many essentials to making sure calves and cows stay healthy during the winter.
- Make sure bedding is dry and warm. Providing lots of dry bedding will help keep the calves warm so that again, they can focus on growth. A good way to test if the bedding is dry enough is to do the ‘kneel test’. If you kneel in the bedding and your knees become damp, that is a good sign that the bedding isn’t dry enough for the calves!
- Last but not least, make sure that YOU and your EMPLOYEES are protected from the harsh cold. Dress in lots of layers and take the time to make sure that you are kept dry and warm.