Calf jackets have proven to help young calves tolerate cold stress and improve health and growth during the winter months. Young calves do not have large body fat reserves to convert for body temperature regulation, and their large percentage of surface area relative to total body size also causes them to lose body heat quickly at low ambient temperatures.
A recent study in the United Kingdom compared 40 Holstein calves reared from December through February. Half received calf jackets from 2 to 12 weeks of age, and half did not. The researchers found that the calves with jackets gained an average of 11.68 pounds more than those without.
In addition, the calves with jackets:
- Ate less feed, resulting in a savings of about $3.77 per head.
- Had increased last rib girth measurement, indicating improved rumen development.
- Had higher fecal scores and a lower incidence of scours.
There are a number of manufacturers and distributors of calf jackets in the United States. Each shares management advice on how to best use and reap the benefits of calf jackets. Here are 10 of their tips:
- Be sure calves’ coats are completely dry before fitting them with jackets.
- Adjust the straps weekly to accommodate for growth.
- Check to ensure no straps are rubbing that could create raw spots on calves’ skin.
- Launder jackets in hot water with detergent, and thoroughly dry between calves.
- Change jackets that become wet for any reason, including weather and scouring calves.
- Bedding is still important. Be sure calves have clean, dry, deep bedding in which they able to nest.
- One rule of thumb for starting to use jackets in the fall is when the daytime high and nighttime low, added together, equal 90˚F or less. Another suggested starting point is when three consecutive nights of a pre-determined temperature -- such as 40˚F -- or less occur.
- Continue to use jackets as long as the ground is frozen.
- In warm stretches, monitor calves to see if they are sweating under the jackets. If so, remove them during the day, as daytime sweating can cause nighttime chilling.
- Remove calf jackets in the morning versus afternoon or evening.