Rainfall ranks as one of the most important factors that influence ranchers’ management decisions, according to North Dakota State University Extension specialists.
This year is no different. Parts of North Dakota are experiencing severe dry weather while others have adequate to plentiful moisture. This situation drives management of native pasture, crop residue and cover crop acres.
Typically, even with good moisture at this time of the year, the nutritional value of native pasture is in decline. This decline is accelerated under dry conditions.
“Early weaning is one of the management decisions that can help reduce pressure on native pastures and extend forage supplies for adult beef cows,” says Janna Block, Extension livestock systems specialist at NDSU’s Hettinger Research Extension Center.
“Early weaning simply means weaning calves at an earlier age to reduce forage usage, while not compromising calf health and performance,” she adds.
Dairy calves often are weaned as early as 8 weeks of age. This is achieved through proper nutrition with feeds that promote rumen development. These feeds enhance the development of the rumen so calves can survive very well without the nursing milk diet.
“From the standpoint of feed efficiency, it is more efficient to feed calves directly than to feed cows to sustain milk production,” Block says.
Beef calves can be early weaned successfully from 60 to 150 days of age.
Most producers will notice that nursing calves also will consume forage, whether through grazing or being fed harvested forages. Research shows that early weaned cows will consume as much as 35% to 45% less forage than normally weaned cow-calf pairs.
Early weaning typically results in improved body condition of dams due to decreased nutrient requirements. A cow weighing 1,400 pounds would require about 16 pounds of total digestible nutrients (TDN) and 2.5 pounds of crude protein (CP) on a daily basis in late lactation. This same cow’s requirements would decrease to 12 pounds of TDN and 1.7 pounds of protein after weaning. In addition, water requirements would decrease by about 55% to 60%.
Distinguishing between early weaning and creep feeding is important, based on goals of each strategy. Creep feeding is providing supplemental feed to nursing calves. The primary goal of creep feeding is to increase weaning weight of calves.
While creep feeding may result in some substitution of forage for creep feed, it does not reduce nursing pressure on cows. Therefore, this practice will not provide the same forage savings and increases in cow condition that can be gained from early weaning, Block says.
Early weaning should not compromise calf health, and performance should be enhanced.
“The key to successful early weaning is to treat groups of calves as unique,” says Gerald Stokka, NDSU Extension veterinarian and livestock stewardship specialist. “Weaning by pasture group is preferred, with no commingling of other groups after weaning for at least 45 days. Even though all calves have been born and raised on the same ranch, the pasture group is the stable unit as it relates to shared organisms and social pecking order.”
If weaning includes commingling all pasture groups at the same time into a common weaning pen or pasture, be prepared to begin treating calves for respiratory disease 10 to 14 days postweaning. Alternatively, make provisions to bring all cows and calves together so the social order and shared organisms of calves can be re-established prior to the stress of weaning. The more space that is provided (pasture weaning), the less the pressure on re-establishing social structure and the less transmission of organisms during this stressful time.
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,” Stokka says. “The lack of adequate passive transfer of immunity from the birth mother to the calf increases the risk of postweaning morbidity.”
Temperature fluctuations may compromise the normal respiratory defense mechanisms, as do heat stress and dusty pen conditions. Dry conditions may result in nutritional stress prior to weaning, so make sure to provide appropriate protein, energy and mineral supplements prior to and after weaning.
“If calves need processing, such as vaccination, deworming etc., do so in the early morning hours or delay processing until the temperatures moderate,” Stokka says. “Processing can be done at the time of weaning; however, only products that benefit the animal at weaning and do not compromise the immune response should be used. Processing done at least three weeks prior to early weaning is preferred and provides the opportunity to administer booster doses postweaning if necessary.”
Facilities may need some remodeling if weaning calves are significantly smaller than normal. Calves become adept at finding ways to return to their dams or at least escaping from the weaning facility. Because smaller and younger calves may have difficulty competing for feed and water, sorting calves into several pen groups based on size and age may be a good idea.
“Early weaning is a management tool that can significantly reduce forage and water demand,” Block says. “In addition, with proper preparation, calf health and performance are not compromised.”
Source : ndsu.edu