Impact of environmental temperature on response of neonatal pigs to an endotoxin challenge

Citation
Ja. Carroll et al., Impact of environmental temperature on response of neonatal pigs to an endotoxin challenge, AM J VET RE, 62(4), 2001, pp. 561-566
Citations number
37
Categorie Soggetti
Veterinary Medicine/Animal Health
Journal title
AMERICAN JOURNAL OF VETERINARY RESEARCH
ISSN journal
00029645 → ACNP
Volume
62
Issue
4
Year of publication
2001
Pages
561 - 566
Database
ISI
SICI code
0002-9645(200104)62:4<561:IOETOR>2.0.ZU;2-I
Abstract
Objective-To evaluate the effect of various environmental temperatures (ET) on the ability of neonatal pigs to cope with an endotoxin challenge. Animals-28 crossbred male pigs that were 24 hours old. Procedure-At 24 hours of age, pigs were placed in environmentally controlle d chambers maintained at 18 or 34 C (14 pigs/ET). Rectal temperatures (RT) were recorded at 15-minute intervals for 3 hours following an IP injection of 0.9% NaCl (7 control pigs/ET) or lipopolysaccharide (LPS; 150 mug/kg of body weight; 7 LPS-treated pigs/ET). Tissue specimens and blood samples wer e collected following the 3-hour challenge period. Results-LPS-treated pigs exposed to 18 C had a period of hypothermia wherea s RT for LPS-treated pigs at 34 C did not differ from control pigs. The LPS -treated pigs maintained at 18 C lost the most body weight during the 3-hou r period and also had the greatest increase in serum cortisol concentration . Serum prolactin (PRL) concentration was decreased in pigs at 18 C, compar ed with pigs at 34 C, Challenge with LPS resulted in an increase in serum P RL concentration at 18 C but had no effect on serum PRL at 34 C. Challenge with LPS resulted in an increase in expression of tumor necrosis factor-alp ha, interleukin-1 beta, and interleukin-6 receptor mRNA in the hypothalamus . Conclusions and Clinical Relevance-Exposure to a cold ET can inhibit the ab ility of neonatal pigs to cope with an exogenous endotoxin challenge. When combined, cold stress and exposure to exogenous endotoxin induces a rapid a nd potentially dangerous loss of body temperature in neonatal pigs.