Submitted to: Meeting Abstract
Publication Type: Proceedings
Publication Acceptance Date: August 17, 1998
Publication Date: N/A
Interpretive Summary: Management decisions can only be considered ideal if information is available about alternatives. This research summary contains information about our research program on the response of animals to temperature and other environmental factors. It is first necessary to relate the response of the animal to the environment and then it is possible to calculate the risks that go along with the wide range of temperatures seen in different climates. In fact, we have found limits or thresholds to help in choosing when and how to react to extreme heat or cold. We have used information about the animal's own body temperature and other body conditions to help identify thresholds. Since the animal can adapt to many environmental conditions, it is necessary to understand the importance of slow or rapid changes in the environment. Summertime heat waves are used as an example of dangerous conditions, the risks to animals, and possible management alternatives. Often times, the management alternatives are possible only with planning. This paper discusses the need to plan.
Technical Abstract: Questions relevant to rational management are approached by evaluating penalties and risks associated with departures from the "optimum" based on livestock responses to their thermal environment. There are two types of responses discussed in this report: 1) integrative response functions which reflect how animals respond over an extended period of time (several days to several weeks or months) to accommodate potential adaptive and compensatory capabilities, and 2) short-term (a few minutes to a few days) dynamic responses of animals to environmental challenges as reflected in influences on feed intake, the endocrine and immune systems, thermoregulation, reproduction, and even survival. Response functions play a major role in strategic environmental management decisions. Dynamic responses are more closely oriented to tactical decisions. Our research has demonstrated the utility of swine response functions as a basis for selecting zones of air temperature associated with performance penalties o 1, 2, 3 or 5%. The value of such performance losses can be weighed against the cost of providing conditions within the prescribed range as a strategic decision-making tool. Our research also provides a better understanding of dynamic responses of livestock to environmental challenges. Results provide guidelines for minimizing risk to animals and provide guidance for monitoring animals during exposure to environmental extremes (e.g., heat waves). Results of these research efforts provide decision-making tools for livestock managers, thus serving as a basis for rational environmental management.