Effects of Preconditioning on Health, Performance and Prices of Weaned Calves

According to the American Heritage Dictionary, to precondition is to condition, train, or accustom in advance. There is no standardized definition for this term as it applies to beef calves prior to, during, and/or after the weaning and shipping period. However, preconditioning is generally used to indicate management practices implemented around the time of weaning that are intended to optimize the animal’s immune system and nutritional status while minimizing stress. The outcome of this process is added value to the entire beef production system. This added value is realized through reduced incidence and associated costs of sickness, improved performance in terms of weight gain and feed efficiency, a reduction in drug use and the labor required to treat and manage sick cattle, and improved beef product quality. Cow/calf producers benefit through the development of a reputation for high quality cattle, utilizing management skills and feed resources to add further value to home raised calves, and the opportunity to capture a larger portion of the revenue in cases where some level of ownership is retained. Organized efforts to encourage standardized management of beef calves prior to weaning and shipment began in 1967. In September of that year, approximately 200 animal and veterinary scientists met at Oklahoma State University to discuss the problems and scientific basis for developing and encouraging these management practices (Gill, 1967). It was at this meeting that the concepts of vaccinating calves prior to weaning or shipping (pre-vaccinating) and “conditioning” calves were combined to coin the term “preconditioning.” In beef cattle, the term “conditioning” generally referred to a combination of management practices such as dehorning, deworming, castrating, weaning, and training calves to eat out of bunks or water troughs. Industry-wide adoption of the preconditioning concept has been painfully slow. Controversy surrounding the topic is still prevalent today. However, recent developments in the U.S. beef industry promise to propel the preconditioning concept forward at a faster rate. Numerous value based marketing programs are now available to beef cattle producers. This marketing approach serves to increase information flow and management coordination up and down the production chain. In this way, stronger signals and incentives are created to encourage the adaptation of the best management practices, such as those associated with preconditioning. The effects of sickness on performance and carcass traits Previous work indicates that animal health and medicine costs are the most important animal performance measures determining feedlot cattle profitability (Gardner et al., 1996). For example, compared with steers without lung lesions, steers with lesions plus active lymph nodes had around $74 less net return (Gardner et al., 1998). The effects of sickness on performance and profitability are also clearly demonstrated in data collected on over 16,000 head of cattle in the Texas A&M Ranch to Rail program (McNeil et al., 2000)(Table 1). In this data, animals treated one or more times for bovine respiratory disease (BRD) were considered to be sick. The number of cattle treated for sickness in a given year ranged from 14 percent to 34 percent, with an average of 22.4 percent. Average medicine costs for each animal treated varied considerably among years with a low of $21 to a high of $38 per head. This data shows that the frequency of the occurrence of BRD and associated medicine costs is difficult to predict. This difficulty arises from year-to-year environmental variation and management differences. Consequently, the true value of preconditioning programs is a moving target and will vary over time and in different situations. In the Ranch to Rail study, cattle identified as being sick gained 0.32 lb/hd/day less compared to cattle that were never treated. This reduction in weight gain translates to less sellable carcass weight. Perhaps a more important question, and one