This problem usually occurs when the calves are less than one month of age. The list of viruses, bacteria, and other agents that can potentially cause scours is quite long. These agents tend to be in the cattle, in the environment, or both in the cattle and the environment.
Health maintenance revolves around tipping the balance in the favor of the calf.
Stated another way, increasing resistance is the same as increasing the activity of the immune system and decreasing the dose is sanitation. The immune system of calves is not fully developed at birth and that is part of the reason they are more susceptible to agents that cause calf scours. Therefore, one of the main goals of prevention is to get the calves' immune system working at optimum levels. Feed the cow adequate energy and protein for the last 3 months of pregnancy. The cows and heifers should be fed enough to gain about one pound per day during this time.