Project Number: 3602-32000-007-00
Project Type: Appropriated

Start Date: Dec 16, 2005
End Date: Dec 15, 2010

Objective:
Objective 1: Identify physiological, immunological, endocrinological and gastrointestinal-microbiological alterations which occur in infected livestock when subjected to common managerial stressors. Objective 2: Understand how handling and transportation stress influence livestock pathogens, such as, Salmonella and Campylobacter, which have the potential to detrimentally affect human health.

Approach:
We will subject livestock to both mixing and transportation and collect behavioral, physiologic, immunologic, endocrine, and bacterial data. The behavior data will include: agonistic encounters, loss of balance, vomiting, standing, lying, stereotypic behavior, and any other abnormal behaviors (i.e. shaking, jumping, etc). The physiologic, immunologic, and endocrine data will include: heart rate, body temperature, cortisol, epinephrine, norepinephrine, dopamine, immune cell populations, interferon-gamma, interleukin-1, interleukin-12, haptoglobin, alpha 1-acid glycoprotien, and immunoglobulins. The bacterial data will include: DGGE pattern, total aerobes, anaerobes, Enterobacteriaceae counts, and the proportion of antimicrobial resistant Enterobacteriaceae in different compartments of the gastrointestinal tract and in mesenteric lymph nodes. Analysis of these collective data will allow for identification of key processes that create high pathogen loads at slaughter plants. Our approach is a strategy that will 1) use a novel technique to monitor the progression of infection of stressed swine, 2) study the influence of mammalian stress hormones on bacteria, and 3) determine physiologically how a dietary supplement can impair bacterial infection. All three of these approaches will provide novel information on how stress influences bacterial pathogens.