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A Ligated Intestinal Loop Model in Anesthetized Specific Pathogen Free Chickens to Study Clostridium Perfringens Virulence
Published on: October 11, 2018
SOURCE AND PORTAL OF ENTRY OF BACTERIA FOUND IN BRUISED POULTRY TISSUE
Abstract:
Bacteriological studies revealed that normal tissue, air sacs, feathers, skin of birds, poultry feed, gut, and chicken droppings were sources of the predominant organisms, including staphylococci, found in bruised poultry tissue. Further investigation of normal tissue revealed that after the intramuscular injection of Staphylococcus aureus, marker strain (MS), the organism was eliminated from these tissues within 7 days. However, when these tissues were traumatized 3 days after injection, the number of the test organism increased, and the organism was present on the 7th day after inoculation. Poultry feed and fecal material contained a large number of staphylococci identical to those isolated from bruised tissue (McCarthy, Brown, and Hamdy, 1963), thereby implicating the gut as a possible portal of entry. When a pathogenic marker strain of S. aureus was established in the intestinal tract of chickens by administering an active culture of this organism either in their drinking water or by gavage, it was recovered from the traumatized tissue. The incidence of positive culture of S. aureus MS in these tissues correlated with age of bruise, reaching 22 to 33% immediately after contusion and at the early stages of healing (1 to 3 days post bruise) and decreasing thereafter from 11 to 0% on the 4th through 6th days after bruise infliction. The air sac was also found to be a site by which bacteria may enter the traumatized tissues, but to a limited extent.
Insights
Bruised poultry tissue can become contaminated with Staphylococcus aureus from the environment or the bird's gut. Trauma to tissue can reactivate dormant bacteria, increasing infection risk.
Area of Science:
- Microbiology
- Poultry Science
- Veterinary Medicine
Background:
- Staphylococci are common in poultry environments, including feed, droppings, and tissues.
- Bruised poultry tissue can harbor staphylococci, but the source and persistence require clarification.
Purpose of the Study:
- To investigate the sources of staphylococci in bruised poultry tissue.
- To determine the role of the gut and environmental factors in S. aureus contamination of traumatized poultry tissue.
Main Methods:
- Bacteriological analysis of various poultry tissues, feed, and droppings.
- Intramuscular injection of Staphylococcus aureus marker strain (MS) into chickens.
- Induction of tissue trauma at different time points post-injection.
- Recovery and identification of S. aureus from traumatized tissues.
Main Results:
- Staphylococcus aureus, once cleared from normal tissue, can proliferate in traumatized tissue.
- Poultry feed and fecal material contain staphylococci similar to those in bruised tissue, suggesting the gut as a portal of entry.
- Establishing S. aureus in the gut led to its recovery from traumatized tissue.
- Positive cultures of S. aureus in bruised tissue decreased as the bruise aged.
Conclusions:
- The gut is a significant reservoir for S. aureus that can contaminate traumatized poultry tissue.
- Tissue trauma can lead to the resurgence of previously cleared S. aureus infections.
- Environmental sources and gut colonization play crucial roles in S. aureus contamination of poultry meat.
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