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Genus brachyspira in birds

phenotypes, phylogeny and pathogenicity

Jansson, Désirée (2009). Genus brachyspira in birds. Diss. (sammanfattning/summary) Uppsala : Sveriges lantbruksuniv., Acta Universitatis agriculturae Sueciae, 1652-6880 ; 2009:14
ISBN 978-91-86195-61-8
[Doctoral thesis]

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Abstract

Spirochaetes of genus Brachyspira colonize the large intestine of some mammals and birds, and cause intestinal disease and production losses in pigs and chickens. The precise significance of Brachyspira spp. colonization in birds, the bacterial species involved, and the epidemiology are incompletely understood. Possible transmission between birds and mammals, and the role of wildlife have previously received little attention. In this thesis intestinal spirochaetes were isolated from commercial laying hens and free-living wild mallards (Anas platyrhynchos), jackdaws (Corvus monedula), rooks (C. frugilegus) and hooded crows (C. corone cornix). The isolates were investigated by phenotypic tests, molecular methods (PCR, RAPD, PFGE, sequencing of 16S rRNA and nox genes) and phylogenetic analysis. Experimental animal models were applied in pigs and mallards to study colonization rates and enteropathogenicity. The results showed that Brachyspira spp. were commonly isolated from the investigated species. Phenotypic and molecular analyses showed considerable diversity, and simultaneous colonization by two or more species or genetic variants of the same species was commonly found. In laying hens, pathogenic species (B. intermedia and B. alvinipulli), presumed non-pathogenic species (B. innocens, murdochii, ‘B. pulli’), and isolates that could not be assigned to any presently known species were isolated. No association with disease or production losses was identified. The etiologic agent of swine dysentery, B. hyodysenteriae, was isolated from mallards, which is the first time from wild birds. A putative novel species, ‘B. suanatina’, was isolated from mallards and Swedish and Danish pig herds. Isolates from both a pig and a mallard were shown to cause diarrhoea in pigs by experimental challenge. In mallards, focal epithelial changes were observed with B. hyodysenteriae and ‘B. suanatina’. Another novel and presumed non-pathogenic species, ‘B. corvi’, from corvid birds, was characterized and provisionally described. The results of the thesis highlight the diagnostic difficulties, the genetic diversity, and suggest that birds may be important reservoirs of Brachyspira spp.

Authors/Creators:Jansson, Désirée
Title:Genus brachyspira in birds
Subtitle:phenotypes, phylogeny and pathogenicity
Year of publishing :2009
Volume:2009:14
Number of Pages:67
Papers/manuscripts:
NumberReferences
ALLI Jansson, D. S., Johansson, K.-E., Olofsson, T., Råsbäck, T., Vågsholm, I., Pettersson, B., Gunnarsson, A., & Fellström, C. (2004). Brachyspira hyodysenteriae and other strongly β-haemolytic and indole-positive spirochaetes isolated from mallards (Anas platyrhynchos). Journal of Medical Microbiology, 53, 293-300. II Råsbäck, T., Jansson, D. S., Johansson, K.-E. & Fellström, C. (2007). A novel enteropathogenic, strongly haemolytic spirochaete isolated from pig and mallard, provisionally designated ‘Brachyspira suanatina’ sp. nov. Environmental Microbiology 9, 983-991. III Jansson, D. S., Råsbäck, T., Fellström, C. & Feinstein, R. Experimental challenge of mallards (Anas platyrhynchos) with Brachyspira hyodysenteriae and ”Brachyspira suanatina” isolated from pigs and mallards. Submitted manuscript IV Jansson, D. S., Fellström, C., Råsbäck, T., Vågsholm, I., Gunnarsson, A., Ingermaa, F. & Johansson, K.-E. (2008). Phenotypic and molecular characterization of Brachyspira spp. isolated from laying hens in different housing systems. Veterinary Microbiology, 130, 348-362. V Jansson, D. S., Fellström, C. & Johansson, K.-E. (2008). Intestinal spirochaetes isolated from free-living wild jackdaws, hooded crows and rooks (genus Corvus): Provisionally designated “Brachyspira corvi” sp. nov. Anaerobe 14, 287-295.
Place of Publication:Uppsala
ISBN for printed version:978-91-86195-61-8
ISSN:1652-6880
Language:English
Publication Type:Doctoral thesis
Full Text Status:Public
Agrovoc terms:birds, swine, crows, layer chickens, spirochaetales, phenotypes, phylogeny, swine dysentery, intestinal diseases, epidemiology
Keywords:Anas, Brachyspira, Corvus, experimental challenge, laying hen, phenotype, phylogeny, molecular characterization, spirochaete, swine dysentery
URN:NBN:urn:nbn:se:slu:epsilon-2772
Permanent URL:
http://urn.kb.se/resolve?urn=urn:nbn:se:slu:epsilon-2772
ID Code:1943
Department:(VH) > Dept. of Clinical Sciences
Deposited By: Désirée Jansson
Deposited On:25 Feb 2009 00:00
Metadata Last Modified:02 Dec 2014 10:15

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