Excellent herd health starts with good husbandry and a close working relationship with your veterinarian. Healthy herds have high reproductive success, few deaths of mature cows, and few deaths of calves from birth to weaning.
I define high reproductive success as a herd that has a high percentage of cows being diagnosed as pregnant and nearly all of those cows giving birth to a live calf early in the calving season. Reproductive success starts with good heifer development that results in heifers that reach an appropriate skeletal size and body condition by the time they give birth to a calf at about 24 months of age so that the calf sired by a bull with an appropriate calving ease EPD can be born without difficulty and will stand and suckle soon after it is born. Mature cows should maintain good body condition throughout pregnancy to ensure a healthy fetus can develop into a healthy calf and so that cows will be in a good body condition going into the next breeding season. Using vaccines that provide increased protection from diseases that can cause abortion such as IBR (infectious bovine rhinotracheitis), BVD (bovine viral diarrhea), leptospirosis, and vibriosis should be done appropriately every year. In addition, screening herd additions for diseases such as BVD and trichomoniasis (trich) is important to decrease the risk of pregnancy loss.
The diseases most likely to affect mature cows usually only affect a few individuals and not the whole herd. Herd management that allows only a few, isolated cows to become ill or to die is the goal of a good herd health plan. While death is the most severe result of disease, becoming sick but recovering has negative effects on a cow’s ability to raise her calf, the likelihood to become pregnant, and animal welfare and wellbeing. Mature cow health is best protected with good husbandry practices that ensure that nutritional needs are met, the housing environment provides protection from mud and weather extremes, and control measures are in place to minimize the risk of diseases and parasites that are common in the herd’s particular geographic area. In addition, when the herd is moved or handled, each cow should be carefully observed for signed of lameness, eye problems, poor body condition, or other signs of illness.
Calf health concerns are somewhat different than the problems faces by mature cows in that diseases that affect calves from birth to weaning often cause large outbreaks that result in a high percentage of the calves in an affected pasture becoming ill. The most common disease problems for calves from birth to weaning are: scours, pneumonia, pinkeye, and heavy parasite (worm) burdens. A good calf health plan starts with calves that are born in a clean environment to dams in good body condition, and the calves are able to stand and suckle shortly after birth so that they consume colostrum and bond to
their mother. Heifers calving for the first time are more likely to have calving difficulty compared to the mature herd; therefore, proper heifer development, bull selection, and close monitoring during calving are required to ensure that calves from heifers get a good start. Not only is being born in a clean environment critical for calf health, living in a clean environment (particularly during the first few weeks of life) is essential to avoid the diseases that most commonly afflict calves. Strategies such as the Sandhills calving system that moves pregnant cows away from cow-calf pairs to new calving pastures every week (or as frequently as possible) keeps the youngest and most-susceptible calves away from older calves that are shedding the most disease-causing germs. Combining such an age-segregation strategy with management to frequently move feeding areas to avoid high-traffic, muddy areas will provide substantial protection from calfhood diseases.
With only a few exceptions, the infectious diseases that are the greatest concern for both mature cow health and the health of calves are due to common germs that are present on all or nearly all farms in a geographic area. Therefore, the most important role for the veterinarian is to determine what has decreased the cow’s or calf’s ability to fight off common germs or what has allowed the number of germs in an area to grow so large that it is able to overwhelm defenses that would typically prevent disease. By identifying what allowed germs to gain an advantage in the never-ending struggle between cattle and the disease-causing agents that live with them, veterinarians will identify the best methods to stop a disease outbreak and to reduce the risk of future problems.
Excellent herd health protects the economic investment in cows and calves, supports high productivity, and ensures good animal welfare for cow-calf herds. Working with your veterinarian to focus on the basics of animal husbandry and health such as good forage management, timely nutritional supplementation, good heifer development, sanitary calving and nursery pastures, proper use of vaccinations, parasite control, and appropriate testing and assimilation of herd additions is required to develop the best herd health program for your herd.