Livestock Update, October 2006
Dr. W. Dee Whittier, Extension Veterinarian, Cattle, VA-MD Regional College of Vet. Med.
Calves that have been weaned before they are marketed are bringing premium prices in Virginia and across the country. This is at least partly due to the estimation of their increased health status but is probably also due to the perception that those who cared enough to market their calves this way probably cared about genetics and other factors that go into the production of high quality calves.
In a conversation with Bill McKinnon the other day he commented how easy it is to sell calves that have been pre-weaned. He also reminded me that in the relative few years since the Virginia Quality Assured (VQA) program was initiated the change in the percent being sold that are pre-weaned has been a flip-flop from few historically to most this year.
The increase in demand for pre-weaned calves comes along with some significant changes in the cattle industry. An increased number of calves have gone straight to feedlots in recent years. Feeders see lots of calves compared to many stocker operators. I’m convinced that they have been quick to recognize the decrease in disease seen in pre-weaned calves.
When we talk about disease in calves we generally are referring to shipping fever, also called respiratory disease or bovine respiratory disease complex. This disease is still the biggest cause of disease loss in the beef industry. In fact, it is accepted that more cattle die of respiratory disease each year than from all other causes, except at harvest. This frustrating disease has withstood many of the efforts to control it that have worked with other diseases. Vaccination has been almost totally successful in controlling a disease like blackleg. On the other hand, even high quality vaccination programs for calves still have associated cases or even outbreaks of respiratory disease. This has led the cattle industry to look for other preventives for the disease.
Shipping fever is not a classical disease where administering the disease agent to test cattle will produce the condition. In fact, administering the most important disease agent (the bacteria Manheimia hemmorhagicum or Pasteurella) even directly into healthy cattle windpipes often fails to result in any sickness. But when a number of other factors we call “stressors” enter into the picture, then these bacteria enter into the lung and multiply there. Table 1 is a list of the stressors that commonly challenge young feeder cattle.
Table 1. Factors that challenge feeder cattle and increase the risk of shipping fever or respiratory disease.
|Weaning||Going without feed||Exhaustion from marketing|
|Castrating/dehorning||Virus infections (colds)||Weather stress|
|Social stress from mixing||Weather stress||Processing calves|
|Going without water||Change in diet||Parasitism|
Prevention of respiratory disease in cattle has been a very difficult medical problem. Huge amounts of effort have gone into vaccination programs in an effort to control the disease. Much of the vaccination effort has been directed at preventing viral infections against the most damaging viruses (IBR, BVD, PI3 and BRSV). Manheimia/ Pasteurella vaccines have been tried for many years with somewhat discouraging results. Vaccines using a somewhat different approach have become available in the last several years and are generally accepted to have a larger influence on reducing the severity of the disease more than reducing the incidence.
As it has become apparent that vaccination programs are not a total solution to respiratory disease, other ways to reduce disease have been sought. Separating the stress of weaning from the stresses of marketing is a natural step. If a system for weaning calves that is low stress (across-fence weaning, for example) the risk that respiratory disease will occur on the farm where weaning takes place can be minimized.
Someone considering pre-weaning calves should closely consider the nutritional program given to calves. Right at weaning, good hay or pasture will encourage calves to eat and reduce stress. After the initial phase, calves should be fed a ration that will provide for at least moderate growth. Generating extra pounds to sell without making calves so fleshy that they will receive discounts at sale should be the objective.
Selling pre-weaned calves is an opportunity for Virginia producers to add value to a product that they have already produced. The added value comes from both increasing selling price and having more pounds to sell. To capture the increased selling price a sales route needs to be used that will advertise the increased value. The VQA program, tele-auction sales (commingled or single owner) or direct sales can all be used to assure that buyers have the chance to recognize the increased profit potential pre-weaned calves have.