Home About Browse Search
Svenska


Clostridium perfringens the causal agent of necrotic enteritis in poultry

Johansson, Anders (2006). Clostridium perfringens the causal agent of necrotic enteritis in poultry. Diss. (sammanfattning/summary) Uppsala : Sveriges lantbruksuniv., Acta Universitatis agriculturae Sueciae, 1652-6880 ; 2006:34
ISBN 91-576-7083-8
[Doctoral thesis]

[img]
Preview
PDF
3MB

Abstract

Clostridium perfringens, an anaerobic Gram-positive bacterium known to be a common pathogen in humans, domestic animals and in wildlife, is the primary cause of clostridial enteric disease in domestic animals. C. perfringens can lead to both clinical and subclinical disease in poultry. Due to the diminished use of growth-promoting antibiotics in the European Union, C. perfringens associated necrotic enteritis and subclinical diseases have become serious threats to poultry health. The objectives of this PhD project were to learn how C. perfringens causes necrotic enteritis in broilers. The genetic diversity of C. perfringens in a wider perspective was also determined. It is of great importance that the plasmid-borne toxin genes are stable, both when the bacteria are transported to the laboratory and at the laboratory, in order that toxin typing of C. perfringens isolates should be accurate. Our results demonstrate that the plasmid encoded genes cpb1, cpb2 and etx are indeed stable under normal laboratory conditions and under conditions normally applying during transportation. Pulsed-field gel electrophoresis (PFGE) was used to explore the genetic relatedness of C. perfringens. The genetic diversity was found to be wide among C. perfringens isolates from different animal species, from food poisoning outbreaks and sewage sludge. Epidemiologically related isolates showed a close genetic similarity, as expected, while isolates with no obvious epidemiological relationship were genetically not so similar. Furthermore, sequence comparison of the cpb2 gene revealed two genetically different populations. The genetic relatedness of C. perfringens isolates from a broiler flock affected by mild necrotic enteritis (NE) was investigated by PFGE. Generally, a low genetic relatedness was found among C. perfringens isolates from these broilers affected by either mild or severe NE. The uniform susceptibility to narasin indicated that the substance can still be used to control clostridiosis, and that development of the resistance observed is slow. In this study C. perfringens also showed a low degree of resistance to most other antimicrobials tested. The exception was the high degree of tetracycline resistance found in C. perfringens in Swedish broilers.

Authors/Creators:Johansson, Anders
Title:Clostridium perfringens the causal agent of necrotic enteritis in poultry
Year of publishing :May 2006
Volume:2006:34
Number of Pages:44
Papers/manuscripts:
NumberReferences
ALLI. Johansson, A., Engström, B.E., Frey, J., Johansson, K-E. & Båverud, V. 2005. Survival of Clostridium perfringens during simulated transport and stability of some plasmid-borne toxin genes under aerobic conditions. Acta Veterinaria Scandinavica, 46(4), 241-247. II. Johansson, A., Aspan, A., Bagge, E., Båverud, B., Engström, B.E. & Johansson, K-E. Genetic diversity of Clostridium perfringens type A isolates from animals, food poisoning outbreaks and sludge. Submitted. III. Johansson, A., Aspan, A., Kaldhusdal, M., Johansson, K-E. & Engström, B.E. Genetic relatedness of Clostridium perfringens type A strains isolated from a broiler flock affected by mild necrotic enteritis. Manuscript. IV. Johansson, A., Greko, C., Engström, B.E., & Karlsson, M. 2004. Antimicrobial susceptibility of Swedish, Norwegian and Danish isolates of Clostridium perfringens from poultry, and distribution of tetracycline resistance genes. Veterinary Microbiology 99, 251–257.
Place of Publication:Uppsala
ISBN for printed version:91-576-7083-8
ISSN:1652-6880
Language:English
Publication Type:Doctoral thesis
Full Text Status:Public
Agrovoc terms:broiler chickens, clostridium perfringens, enteritis, necrosis, genetic variation, electrophoresis, antimicrobials, toxins, resistance to chemicals
Keywords:Clostridium perfringens, necrotic enteritis, poultry, genotyping, PFGE, antimicrobial, toxins, plasmid stability
URN:NBN:urn:nbn:se:slu:epsilon-1084
Permanent URL:
http://urn.kb.se/resolve?urn=urn:nbn:se:slu:epsilon-1084
ID Code:1139
Department:(VH) > Dept. of Biomedical Sciences and Veterinary Public Health
Deposited By: Anders Johansson
Deposited On:29 May 2006 00:00
Metadata Last Modified:02 Dec 2014 10:09

Repository Staff Only: item control page

Downloads

Downloads per year (since September 2012)

View more statistics

Downloads
Hits