With the mild fall we experienced this year, many ranchers may still have cow/calf pairs out on pasture. Whether calves will be retained and backgrounded or sold shortly after weaning, it is important to consider the impacts of weaning strategies on calf health and performance, says Janna Block, North Dakota State University Extension livestock systems specialist at the Hettinger Research Extension Center.
Many producers wean calves around the same time every year; however, factors that should be considered include cow body condition, feed resources, and the timeline for feeding and marketing the calf crop. If cows are in poor body condition and forage conditions are poor, reducing nutritional demands due to lactation is one of the most effective strategies to improve condition and prepare for the next calving, says Block. Since nursing calves also consume forage at around 2% to 2.5% of body weight, weaning can also reduce forage demands and allow producers to extend the grazing season.
Besides birth, weaning is one of the most stressful periods in a calf's life. Multiple stressors occurring at one time can multiply the negative effects. Types of stress include removal from the dam and commingling with herdmates, processing (weighing and vaccinations), changes in feed and a new pen or pasture environment. Increased levels of cortisol in the blood due to stress can lower immune function, increase susceptibility to disease, and reduce weight gains. Taking steps to minimize stress during this period will optimize health and performance of weaned calves.
Weaning strategies
Traditionally, calves are weaned by abrupt separation from the dam. While this method is commonly utilized due to reduced inputs, it results in maximum stress and bawling calves. Some research indicates that calves may walk up to 10 to 12 miles daily and eat less feed when weaned through this method. In addition, a higher percentage of abruptly weaned calves may require treatment for respiratory diseases.
Two-step weaning strategies do not allow suckling but allow the calf to maintain contact with the dam prior to separation. This method can be implemented using fenceline weaning or anti-suckling devices such as nose flaps.
If considering fenceline weaning, the recommendation is to move the cows to an adjacent drylot or pasture and allow the calves to remain in the familiar environment. This strategy requires secure fences in order to work. Additionally, if forage quality or quantity is a concern, producers may need to provide good-quality grass hay to calves to reduce weight loss during the weaning period. Once calves are weaned and eating forage, they can be moved to a drylot or fed on pasture, depending on feed resources.
"Utilizing nose flaps requires additional handling, but reduced stress and better performance may be worth it," says Block. "Calves can be fitted with nose flaps, vaccinated and turned back out with cows for another four to five days. If left on longer, there is increased irritation in the nose, more lost nose flaps and an increased incidence of "cheaters" who have learned to nurse around them. To remove the flaps, calves must be run through a chute a second time. These devices can be washed and reused in most cases."
Health management
If cow/calf pairs were split across multiple pastures this summer and fall, producers should consider weaning by pasture group with no commingling for at least 45 days after weaning. Even if all calves were born and raised on the same ranch, cattle in various groups have likely developed a different social structure and may have been exposed to different organisms or health challenges. Commingling all pasture groups at the same time into a common weaning pen or pasture can lead to increased incidence of respiratory disease post-weaning. If possible, bring all cows and calves together in a common pasture several weeks prior to weaning to allow them to acclimate.
Other potential risk factors may influence health at this time as well. Lack of passive immunity, temperature fluctuations, heat stress, nutritional stress prior to weaning, dusty pens, and handling stress may negatively impact the healthy transition to weaning. The lack of adequate passive transfer of immunity from the birth mother to the calf increases the risk of post-weaning morbidity. Temperature fluctuations may compromise the normal respiratory defense mechanisms, as do dusty pen conditions.
Weaned calves are at high risk for parasite infestations, which can impact immune function and reduce feed intake. Calves should be dewormed when they receive their first round of shots if possible. Although vaccine protocols vary, calves should be vaccinated against clostridial and bovine respiratory disease (BRD) pathogens. Consult with your herd veterinarian to develop vaccine protocols.
Facilities and stockmanship
Pre-check all facilities such as gates, chutes, alleys and crowd tubs to ensure everything is in good working order. Make sure surfaces are non-slip and eliminate packed snow or ice to avoid falls. Try to avoid weaning if there is a big cold front coming and reschedule if necessary.
Maintaining vaccines at the required temperatures can be challenging in the cold. Freezing will inactivate modified live vaccines and can create compounds that can increase stress. Use a well-insulated cooler and store vaccine guns appropriately when not in use.
"The importance of animal handling during weaning shouldn't be underestimated," says Block. "Excitement caused by loud and aggressive interactions with humans will add stress and could reduce immune function. Aggressive cattle handling will also slow the rate at which calves adapt to new feed and water resources, and could influence temperament throughout the feeding period. This will increase flightiness, decrease time spent at the feed bunk, and cause an overall decrease in weight gain, feed efficiency, and cost of gain. It is a good practice to have the same person carefully walk pens with newly-weaned calves to familiarize them with their new environment."
Feeding management
Proper nutritional management of weaned calves is critical in ensuring optimal health and performance. For the first few days, calves should be provided with high-quality, long-stem grass hay, similar to what they may have consumed on pasture with their dams. If calves have been consuming creep feed, it should be made available in the weaning pen. Putting familiar feed in bunks is a good way to train calves to eat. Place bunks or self-feeders perpendicular to the fence line so that calves will bump into their feed. Some producers use a palatable molasses-based mineral lick tub to get additional nutrients into the calves and stimulate salivation, which increases feed and water intake.
Clean and highly-available water is very important during the weaning period. Ideally, at least 10% of cattle in the pen should have the ability to drink at one time. Water tanks should be checked daily and kept clean to avoid algae growth or contamination from feed and manure. It may be advisable to place additional water tanks in the weaning pen along the fence line until calves have adapted to their new water sources.
There are many different weaning strategies that can help reduce stress and adequately prepare calves to make a smooth transition. Implementing some of these strategies can increase health, resilience and overall performance of calves as they move on to the next phase of the production cycle.
Categories: North Dakota, Livestock, Dairy Cattle