During the last trimester of pregnancy in beef cows, the fetus grows rapidly, placing increasing nutrient demands on the cow.
In addition, cold weather increases the cow’s nutrient requirements.
“Body condition plays an important role in successfully wintering beef cows,” says Yuri Montanholi, North Dakota State University Extension beef cattle specialist. “Late weaning, overstocking, late supplementation, poor parasite control programs and inadequate winter rations all can lead to cows in poor body condition.”
Montanholi and other NDSU Extension livestock specialists say the best time to increase body condition is right after weaning, when nutrient requirements are lowest. The goal is to achieve a condition score of five for mature cows and six for first-calf heifers during this period, and then maintain condition through late gestation and into calving.
“If cows are in poor condition now, it can be more challenging and/or expensive to meet increased requirements,” says Janna Block, Extension livestock systems specialist at NDSU’s Hettinger Research Extension Center. “However, numerous studies have established a relationship between adequate body condition at calving and breeding with subsequent reproductive performance. The period post-calving is less favourable for increasing fatness, as the majority of nutrients are used for milk production instead of increasing body condition.”
Proper care essential
The third trimester has a very large impact on the cows as they approach their due date. Most cows handle pregnancy well; access to the proper feed, good water and a reasonable space with wind protection will keep a cow content. She likes a little independence and has no problem marking her space and waiting for the calf. Those herds are in for a pleasant calving season, especially if the pre-calving practices have been done and no further work is needed to prep the cow, Montanholi says.
But what about cows that are less content? Are they thin, hunched up, standing in the corner, bellowing, walking or distraught? If so, get to know your veterinarian, the livestock specialists recommend. These are signs that trouble is brewing, including calving issues, poor colostrum, mothering challenges, fatigue and, later on, scours, along with associated health problems.
“Maybe some extra feed now is really worth it, especially if formulated according to herd needs,” says Gerald Stokka, NDSU Extension veterinarian and livestock stewardship specialist. “Contact your county agent for further support.”
Reducing nutrient intake prior to calving will not reduce calf birth weight or the incidence of dystocia or calving difficulty. Low planes of nutrition have been shown to have no effect or only slightly decrease birth weight.
Conversely, calving difficulty typically increases with reduced nutrient intake because the cow tends to be weaker. In addition, this practice results in weak calves that are less active immediately after birth, which can compromise their survival or productive performance later in life, Stokka notes.
Calf housing and management
Don’t overlook calf housing and dynamics as part of pre-calving considerations, the specialists advise. The second most relevant cause of calf death is calf diarrhea (also known as calf scours). Scours prevention focuses on two key areas: the health of the calf and cleanliness of the environment.
Optimal calf health is achieved through proper care of the cow prior to calving and ensuring calves have adequate colostrum intake at birth. In some scenarios, vaccination against scours is helpful. Producers should ask their veterinarian about vaccinations.
Because scours prevention is related to cleanliness, producers could consider approaches to ensure that the calving area is clean. Calves may be exposed to pathogens through direct contact with muddy or dirty teats, so calves will not be infected from the ground or even from dirtiness found in their cows’ teats.
A potential management tool to minimize the issue of scours is the Sandhills Calving System. Typically, calves born early in the calving season do not have calf scour problems. However, after several waves of calves have been born, pathogen levels reach an infective threshold and calf scours can become a major problem. The Sandhills Calving System incorporates the use of multiple calving areas on pasture.
Cows are calved in a calving area, and after seven to 10 days, pregnant cows are moved to a new area to calve and the cow-calf pairs are left behind in the area in which they calved. The next group of cows will calve in a fresh, clean environment for seven to 10 days and then move on.
Soon, the wet, struggling calf will arrive with a strong desire to nurse and receive a good amount of colostrum. Chances of survival are increased once a calf is dry with a full supply of milk. However, some cows don’t produce an adequate amount of colostrum or of desirable quality, which may be related to an inadequate nutrition plane during the pre-calving period.
“Pre-calving management is a key component for a successful cow-calf operation,” Montanholi says. “There are no shortcuts because cows have requirements.
“Management means meeting all the requirements in a cost-effective manner,” he adds. “This will pay dividends in terms of cow performance and calf health. Are the cows content? They should be, and the results will be evident when pregnancy checking them and when weaning their good-looking calves.”