As temperatures continue to drop, dairy and beef cattle and their offspring are at an increased risk for cold stress, Maristela Rovai, assistant professor and South Dakota State University Extension dairy specialist, noted.
"With daytime temperatures in the double digits below zero for next week, dairy producers should be prepared for cold weather conditions that can affect young stock and lactating cows," Rovai said.
Lactating cows that are adequately fed should withstand cold conditions as long as they are kept dry and not exposed directly to winds. Keep the housing area dry and free of manure, and provide an ample supply of dry, clean bedding daily.
Colostrum's role in calf survival
Survival rates for calves that become exposed to cold temperatures and don't immediately ingest colostrum are low. "Calves need colostrum for energy and antibodies to protect against the cold and possible future diseases," Rovai explained.
Rovai added that a calf's ability to absorb antibodies from colostrum diminishes as its body temperature becomes colder. "It's really important to feed calves within one to two hours after being born and still warm to assure optimum colostrum absorption. In cold weather, their body temperatures will drop faster," she said.
Colostrum has important amounts of antibodies (like immunoglobulin G) and also has higher levels of fat and protein than regular milk. These milk components will be key in protecting the calf from the cold temperatures. A newborn calf's temperature is about 103°F, so if it drops below 100°F, the calf needs immediate care and warming, Rovai noted.
The colostrum, milk replacer or homogenized milk as needed should be provided by bottle or tube. Recommendations are to feed at least a quart. If the calf is too cold to suck the bottle, use the appropriate feeding hoses. Recheck the calf to ensure that its body temperature is rising.
Teat health of lactating cows
Rovai noted that teat skin chapping (frostbite) can become a problem for lactating cows during cold, windy weather. "Chapping makes the teat more susceptible to bacterial infections, particularly Staphylococcus," she said.
Recent research indicates that teat dipping should be continued during cold, windy days. Pre- and post-milking teat dips should include skin conditioners like glycerin and lanolin.
Producers should dry teats and udders effectively. Cows should not be turned outside on cold and windy days until the teat dip has dried for one minute. Rovai also pointed out the cold weather guidelines from the National Mastitis Council, which include:
*In very cold weather, it may be advisable to dip just the teat end.
*When teats are dipped, dip only the end, and blot off any excess with a single-use paper towel.
*Teats should be dry before turning cows out of the barn.
*Warming the teat dip reduces drying time.
*Windbreaks in outside holding areas provide some protection.
*Fresh cows with swollen udders are more susceptible to chapping.
"Always remember that prevention is the key," Rovai said.
Mastitis is a possible outcome during winter as well, and the cows affected will have to be monitored closely. If injury has already occurred, skin chapping and the loss of at least the teat end are likely. When the teat end is damaged, the sphincter that closes the teat canal is also non-functional, predisposing the quarter to bacterial invasion.
More tips for calves
When it comes to caring for calves, South Dakota State University Extension dairy field specialist Tracey Erickson reminded producers that cold stress starts at 60°F in calves younger than 21 days of age or if the temperature drops below 42°F in calves more than 42 days of age.
"Obviously, we are experiencing some serious cold stress right now," Erickson said.
She shared the following tips to help dairy cattle producers care for calves as well as mature cattle:
* Get calves off to a good start in the first 48 hours of life by following proper protocols for newborn calves, especially drying them off as quickly as possible after birth and making sure they are consuming four quarts of high-quality colostrum within the first 12 hours of life, as well as giving proper vaccinations and dipping their navels.
* Consider using a calf warmer to quickly dry newborn calves and help increase their body temperature.
* Use deep and dry bedding. Provide a proper nest: When a calf is lying down, as a guide, its feet and legs should not be visible.
* Use calf blankets, because even though they add extra expense, they are reusable and provide an extra layer of protection for calves. Make sure to adequately clean and dry blankets between uses.
* Proper ventilation is important, but also prevent direct drafts from hitting young calves. Fresh air helps reduce the presence of airborne pathogens and ammonia that is produced by urine and manure.
* Offer additional feedings per day. It's necessary to increase feedings to provide 1.50-2.25 lb. of milk replacer powder per day with 20% fat in order to provide adequate energy intake daily.
* When it is extremely cold, feed 0.25 lb. per day of additional 60% fat supplement in the milk during the first 14 days of life. Many commercial products are available. Taper off feeding the supplement slowly as calves begin to consume starter.
* Be consistent in feeding times, making sure milk is warm yet does not scald the calf's mouth.
* Try other options of increasing caloric intake. Provide warm water above 102°F about 30 minutes after feeding. Water is essential to start and keep the digestive track of the calf working properly, along with promoting dry matter intake. Again, be careful not to get the water too hot so it doesn't scald the calf's mouth.
* Provide a high-quality, fresh starter daily (free of mold and fines) to encourage daily intake.
* Last, producers/employees should take care of themselves so they can be vigilant and observant as they care for the animals.
To learn more about how to care for and protect calves as well as mature dairy and beef cattle from cold stress, visit iGrow.org. There is also a six-category scale to help identify the risk of hazardous conditions for newborn livestock, ranging from none (green color) to extreme (red color), that's available by viewing Weather Forecast Tools for Newborn Livestock.