December 12, 2003
Winter winds, wet weather stress cattle, say two Purdue experts
WEST LAFAYETTE, Ind. - Humans can zip up their jackets and put on hats and gloves when the freezing temperatures of winter arrive, but cattle only grow a fuller coat of hair.
While producers can't bundle up their livestock, there are precautions they can take to help their cattle battle winter weather, say two Purdue University experts.
Mike Schutz, Purdue Extension dairy specialist, and Ron Lemenager, Extension beef specialist, said cold, wet weather is cattle's worst enemy.
"We know that cattle are fairly tolerant to cold," Schutz said. "The problem is that people aren't going to spend as much time observing them. If they are wet with near zero degree temperatures and even colder wind chills, they will suffer and potentially get sick."
If the wind chill drops below zero, cattle need special attention, Schutz said. Producers should provide shelter from prevailing winds to ensure cattle's safety. This can be done with wooden or shade cloth windbreaks, or temporary relief is possible by using round bales and farm equipment. Grazing cattle also should have access to natural or man-made windbreaks in the form of a shelter, building or tree line.
Lemenager said beef cattle grazing in a pasture also will benefit from bedding.
"Bedding is an absolute must," Lemenager said. "Bulls, especially, require bedding so they don't get frostbite of the scrotum, and cows and calves will also benefit. Bedding can be done by busting some straw bales throughout the pasture or unrolling round bales."
Cold rains are more dangerous to cattle than blankets of snow, and frostbite is the most obvious ailment, Schutz said. Dairy cattle aren't likely to develop pneumonia if they are getting an adequate energy supply through their feed and have good ventilation. Schutz said cattle will consume 15 percent to 20 percent more feed in extremely cold conditions.
The rule of thumb for beef cattle is that the energy requirement increases 13 percent for each 10 degree drop in temperature below 30 degrees for cattle with moderate body condition and a winter hair coat, Lemenager said. Energy requirements increase 30 percent for each 10 degree drop in temperature below 30 degrees when cows are wet, thin or still have a summer coat.
"With this in mind, at a zero degree wind chill, a 90 percent increase in energy is needed for a cow that is wet, thin or has a summer coat," Lemenager said. "This increased energy requirement cannot be met by putting more hay out; it will require switching to higher quality feeds or by supplementing with grain."
Care requirements are different for calves. Calves are more susceptible than cows and heifers in winter because they typically are outside or in colder buildings. Calves should be kept dry and supplied with higher energy feed. For bottle-fed calves, this would constitute a 20 percent fat milk replacer. Dairy calves housed in hutches also should have a dry environment with extra bedding, Schutz said. Newborn beef calves and their mothers can be housed in a barn for 24 to 48 hours after birth to allow them time to dry and for the calves to consume colostrum, Lemenager said.
Other precautions can be taken for dairy cattle, Schutz said. Walkways for dairy cows can become slippery, causing more problems.
"Producers should have a plan for moving cows to the milking parlor in icy conditions," Schutz said. "This can be done by de-icing slippery, unprotected walkways in free stall facilities or providing traction by using sand or fine gravel in walkways between a cow's paddocks."
Frozen teats are a problem that also may be encountered in frigid temperatures. Schutz said teat dips are available for cold temperatures, or milkers can dip the teats with their usual teat dip and blot them dry after 30 seconds. Cows and heifers with udder edema should be kept inside to prevent teat freezing.
"Avoid the use of salves or ointments, as these do not provide much protection and increase the risk of spreading herpes mammalits, which cows are more susceptible to in times of cold stress," Schutz said.
A contingency plan should be prepared for winter months, Schutz said. He said it is especially important to ensure that heaters on water sources are in good shape and a manure-handling plan is in place if the alley scrapers or flush valves freeze.
Writer: Michelle Betz, (765) 494-8402, firstname.lastname@example.org
Sources: Mike Schutz, (765) 494-9478, email@example.com
Ron Lemenager, (765) 494-4817, firstname.lastname@example.org
Related Web sites:
Beef @ Purdue: http://www.ansc.purdue.edu/beef
Dairy @ Purdue: http://www.ces.purdue.edu/anr/anr/anr/dairy/frame.htm
Purdue News Service: (765) 494-2096; email@example.com