Date of Award
Master of Science
Lance H. Baumgard
Heat stress (HS) negatively affects pig performance variables and is thus a costly industry issue. It is unknown whether or not HS directly or indirectly (via reduced feed intake) is responsible for the suboptimal production. To account for differences in nutrient intake, we utilized an ad-libitum thermal neutral control group and a pair-fed thermal neutral control group of pigs. In these experiments, pigs in HS conditions had increased body temperatures, reduced feed intake, and lighter body weights compared to controls. Presumably, this production difference may also includes a difference in body composition as HS pigs have increased circulating insulin levels, decreased basal lipolysis, and increased adipose tissue lipogenesis compared to bioenergetic controls. In addition, HS pigs had increased markers of protein catabolism. Heat stress pigs also had compromised intestinal integrity, but this appears to be due to be confounded by reduced nutrient intake, as pair-fed controls had similar intestinal dysfunction characteristics. In conclusion, heat stress directly and indirectly (via reduced feed intake) affects post-absorptive metabolism and intestinal integrity and both variables probably contribute to decreased growth parameters in young pigs.
Pearce, Sarah, "The effects of heat stress and nutritional status on metabolism and intestinal integrity in growing pigs" (2011). Graduate Theses and Dissertations. 12065.