Fall preg checking provides convenient time to evaluate body condition for calvingWritten by Emilee Gibb
As many cattle operations begin pregnancy checking their bred cows this fall, producers also have the opportunity to evaluate body condition and determine if different management strategies are needed before winter begins.
In a webinar discussing how to improve weaning weights, conception rates and calf health, Saskatchewan Regional Livestock Specialist Naomi Paley urged producers to consider the long-term impacts that body condition has on rebreeding, weaning weights of the current year’s calf crop and weaning weights of future year’s calf crops.
Ideally, Paley suggested that producers evaluate their animals hands-on and assign body condition scores at least three times per year.
“If we can at least get our hands on them once or even twice during the year, that’s a benefit, and we’re going to be able to use that information to help us be a better manager,” said Paley.
Fall is a convenient and important time to evaluate body condition, continued Paley.
“The fall time is a good time to evaluate body condition, when we’re processing cattle or running them through the chutes. In the fall, we really want to have those cows in good shape,” she said.
Paley advised producers to consider feed costs when looking at maintaining or adding weight to an animal.
“It’s more expensive to put weight on a cow during the winter than it is to maintain her in good condition,” she said. “Our feed costs are higher for that cow if we’re trying to put condition on her during the winter, and it’s also biologically expensive.”
An average 1,350-pound cow needs to gain 200 pounds of fat to increase one full body condition score.
Adding 200 pounds would equate to 25 bushels of barley or 2,000 pounds of high-quality hay.
“There’s definitely a feed cost associated with trying to put body condition back on to a cow and get caught back up to where she needs to be to have a healthy calf and rebreed in a timely manner,” continued Paley.
“There are those who think that burning body condition or burning some backfat off of the cow is a good way to try and make use of extra reserves that the cow has and that they can sort of bank on that,” said Paley.
However, she noted, “There are some biological costs associated with that.”
A cow receives approximately 900 megacalories of energy for every unit of body condition that is lost. Alternatively, it takes about 1,200 megacalories of energy for the cow to gain one unit of condition.
The extra biological cost of gaining weight back results in a loss of efficiency of approximately 50 percent, explained Paley.
“We can see that it’s a really inefficient system, and it’s going to end up costing us in the end one way or another when we’re counting on sort of farming the fat off of the back,” she said.
Growth and health
During calving and lactation, cow body condition has a significant impact on calf health and growth.
Cows that are below desirable body condition at calving or losing condition after calving may have a five to 25 percent reduction in calf weaning weight, said Paley.
“This is largely due to the reduced nutritional value of the cow’s milk and the amount of nutrition the calf is receiving during the nursing period,” she continued.
Because of the reduced nutritional value of the milk, the calf’s immunity will be suppressed. Reduced immunity combined with reduced weight gain because of lower milk production can ultimately lead to lower weaning weights, Paley explained.
Body condition at calving and throughout lactation is important for timely rebreeding, said Paley.
“Contrary to some management systems, the goal is not simply to get our cows bred. We want them bred early,” she emphasized.
Every time a cow misses a cycle or doesn’t become pregnant has a direct impact on weaning weight of the calf.
“Every time a cow misses a cycle or doesn’t get bred on a cycle, she remains open, so the calf is 20 days younger,” said Paley. “If our calves usually gain about two pounds a day, it’s 40 pounds lighter, which can account for a $90 per head loss every time a cow skips a cycle and doesn’t get bred.”