|Carroll, Jeffery - Jeff Carroll|
Submitted to: Livestock Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/21/2003
Publication Date: 1/1/2004
Citation: CARROLL, J.A., FANGMAN, T.J., HAMBACH, A.K., WIEDMEYER, C.E. THE ACUTE PHASE RESPONSE IN PIGS EXPERIMENTALLY INFECTED WITH ESCHERICHIA COLI (E. COLI) AND TREATED WITH SYSTEMIC BACTERICIDAL ANTIBIOTICS. LIVESTOCK PRODUCTION SCIENCE. 2004. V. 85. P. 35-44. Interpretive Summary: The overall objective of this research was to evaluate the effects of antibiotic treatment following pathogen exposure in young pigs. We experimentally infected weaned pigs with Escherichia coli (E. coli) and subsequently treated them with a commonly-used antibiotic to determine whether or not the antibiotic treatment would cause an alteration in the immune and stress systems of the pigs. Our data demonstrated that antibiotic treatment resulted in a more severe response with regard to serum hormone profiles and the elevation in rectal temperature associated with the E. coli challenge. Additionally, we did not observe any beneficial effects in the present study with regard to overall recovery of the pigs which received the antibiotic treatment compared to those pigs with received no antibiotics following the E. coli challenge. These data highlight the importance of judicial use of antibiotics in swine production, and suggest that the dynamics associated with the physiological and immunological responses following antibiotic treatment during E. coli outbreaks warrant further scientific investigation. Given that this research has the potential to significantly impact the economics associated with swine production, as well as the overall health and well-being of swine, it will be of interest to swine veterinarians and swine producers throughout the United States as well as other countries. This information will also be of interest to all individuals associated with swine production including scientists in academia, government, and industry.
Technical Abstract: Our objective was to evaluate changes in serum C-reactive protein (CRP), haptoglobin (HG), cortisol (CS), tumor-necrosis factor-alpha (TNF-alpha), and rectal temperature (RT) in response to an acute enterotoxemia elicited by antibiotic administration. Twenty-four, 3-week old pigs were individually housed and provided feed and water ad libitum. Twelve pigs were non-surgically cannulated one day prior to blood collection while RT was monitored on the remaining 12 pigs. All pigs received an oral 10-ml dose of 2.4 X 10**8 colony-forming units of E. coli K88. Five hours later, six pigs in each group were injected with 0.5 ml of saline (Group A) and six pigs in each group were injected with 25 mg (0.5 ml) of antibiotic (Ceftiofur HCl; Group B). Data collection occurred hourly from 1 hr before to 5 hrs post-E. coli ingestion (PRE). Between 5 and 8 hrs, data were collected every 0.5 hr and at 24 hrs post-E. coli ingestion (POST). During the PRE period, RT increased over time (P < 0.0001) in both groups. During the POST period, a time x treatment interaction (P < 0.02) was observed such that the Group B pigs had the highest RT. There was a time x treatment interaction (P< 0.0001) for serum CRP such that CRP increased in Group B at 0.5 hr post-antibiotic administration. An overall time effect (P < 0.01) was observed in the PRE and POST period for serum HG, with the greatest concentrations observed at 24 hrs POST. Serum CS increased (P < 0.0001) over time for both groups during the PRE period. During the POST period, a time x treatment interaction (P = 0.05) was observed such that serum CS was higher in the Group B pigs. Serum TNF-alpha was undetectable throughout the entire blood collection period. Results indicate that antibiotic treatment post-E. coli ingestion alters the immunological response in pigs.