Let it snow

Whether in town or on the farm, the winter season has many wonders.

For 2013, the winter weather has left many livestock owners wondering if they ever will get caught up. With crops finally harvested and forages delivered to the feed yard, the last tune many livestock producers may be humming is one you often hear entertainers Dean Martin or Frank Sinatra singing this time of year: "Let It Snow!"

A quick peek at the calendar tells us that the winter solstice (Dec. 21) has just passed, yet in many parts of the country, winter weather has been a familiar scene for the past month. For dairy producers, if you haven't reviewed your calf milk feeding procedures for winter, now is the time to do it.

The young calf has limited reserves of energy when exposed to temperatures below its lower critical body temperature for extended periods. These reserves are depleted quickly in approximately 18 hours for the newborn calf.

Any time the temperature drops below 55 degrees Farenheit, calves will require extra energy just for maintenance. The lower the temperature falls, the more energy calves will need just to maintain themselves and stay warm.

Research under controlled dry conditions with adequate bedding indicates that calves housed at 24.8 degrees Fahrenheit require approximately 30 percent more calories for maintenance. This number will increase as air temperature declines and humidity rises, and if calves are subject to wet bedding.

Adding extra bedding, straw in particular, will help raise the ambient temperature of the calf. On average, when the calf can nest fully in the straw, its surrounding temperature will rise by 39.2 degrees.

For example, at about 20 degrees Fahrenheit, young calves will need approximately 1.5 times as much energy for maintenance. At minus 20 degrees Farenheit, calves will need twice as much energy for maintenance, compared with when the temperature is above 60 degrees Fahrenheit.

When a calf falls under a negative energy balance, its immune status can be compromised easily and the calf becomes susceptible to bacterial and viral infections. This drain on energy also means that feeding calves additional energy is important to maintain growth rates during cold weather.

Some feeding strategies include:

• Feed extra milk replacer powder in the same amount of water.

• Feed more overall volume of milk or milk replacer.

• Feed a milk replacer with a greater fat composition.

• Add a fat supplement to the milk replacer.

• Use a high-quality milk replacer.

Quality is important to calves. Fat and its source can ensure a high absorption rate to best meet their energy needs, especially in cold-stress conditions.

Young animals require highly digestible fats and oils, with a correct fatty acid profile and saturation structure to provide a profile similar to milk fat.

Correct mixing of the milk replacer and temperature of the water used will provide a more uniform blend and low fat particle size (less than 1.5 microns).

These factors encourage optimum absorption capacity by the young calf.

Lastly, feeding more of an appropriately balanced milk replacer diet to meet requirements for energy and protein-allowable gain appears to be the most systematic solution to cold-stress challenges. Feeding more starter will not help the young calf maintain a steady rate of gain during cold weather conditions.

So, whether you use a single feeding strategy or a combination, make sure to provide plenty of fresh water and get in the spirit of the season: "Oh, the weather outside is frightful, but my calves are warm and fed full. And since my calves have no better place to go, let it snow, let it snow, let it snow!"

Editor's note: Schroeder is a dairy specialist for the North Dakota State University Extension Service.