ABSTRACT Transportation and handling is generally regarded as stressful to cattle and includes both physical and psychological stimuli that might be aversive. Historical accounts relate high mortality during the early days of transport and concerns for the welfare of cattle that are similar to those today. Behavior, pathology, and physiology are all used to identify stress in response to transportation. Physiological measures indicate that transport of cattle can result in immune suppression, which can lead to increased susceptibility to disease and might result in increased pathogen shedding. Empirical evidence shows that the neutrophil:lymphocyte ratio is markedly increased when cattle are handled and transported. Agonistic behavior also seems to be decreased by crowding and motion of the truck. Loading, loss of balance, and falling are distressful to cattle. For example, mean heart rates of cattle transported on smooth roads are lower than those of cattle transported on rough country or suburban roads with frequent intersections. Age at transport might also play a role. Young cattle (less than 4 wk old) do not tolerate transport as easily as older cattle, and young cattle do not show a typical physiological stress response as seen in older cattle. This fact, along with mixing practices typical of loads of calves, may make these animals more susceptible to disease. Various remedial strategies have been attempted to decrease cattle response to transportation stress. These include preconditioning, administration of vitamins, vaccines, feeding high-energy diets, and electrolyte therapy. These approaches to managing transport stress have met with little success. Newer methods to reverse the negative physiological responses and to assess behavior during transport are needed. Also research is needed to elucidate the relationship of transport stress to the spread of pathogens of concern to food safety.
Implications
The United States has fallen behind in the investigation of transportation of beef cattle and how such transport affects welfare. We risk accepting standards derived from research outside of the United States when regulatory oversight eventually becomes a reality for livestock transportation.
Key Words: Animal Welfare, Cattle, Stress, Transport
© 2001, by the American Society of Animal Science. All rights reserved.
J. Anim. Sci. 2001. 79:E102-E109
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