Carriage of Brachyspira hyodysenteriae on common insect vectors.

Autor: Blunt R; School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, Leicestershire, United Kingdom., Mellits K; School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, Leicestershire, United Kingdom., Corona-Barrera E; Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Tamaulipas, Ciudad Victoria, Tamaulipas, México., Pradal-Roa P; Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autonoma de Mexico, México City, México., McOrist S; Scolexia Avian and Animal Health Consultancy, Norwood Crescent, Moonee Ponds, Victoria 3039, Australia. Electronic address: smcorist@scolexia.com.au.
Jazyk: angličtina
Zdroj: Veterinary microbiology [Vet Microbiol] 2022 Jun; Vol. 269, pp. 109417. Date of Electronic Publication: 2022 Apr 09.
DOI: 10.1016/j.vetmic.2022.109417
Abstrakt: The interactions of likely insect and murine vectors of the causative agent of swine dysentery, Brachyspira hyodysenteriae, were investigated. Insects were collected and analysed from 3 pig farms positive for B hyodysenteriae. Within these farms, several Musca domestica and Orphyra adult fly, Blatta sp. cockroach digestive tracts and hover fly (Eristalis sp) pupal form contents were positive in a standard PCR assay for B hyodysenteriae, whereas all other insect samples on these and case control farms were negative. In challenge exposure studies, B hyodysenteriae DNA was detected in the digestive tract of cockroaches and M domestica flies from day 1 post-inoculation with cultured B hyodysenteriae, for up to 5 days or 10 days respectively, while control non-inoculated insects remained negative. Isolates consistent with B hyodysenteriae were only cultured from frass samples of these inoculated cockroach and flies on days 1-3 post-inoculation. Isolates consistent with B hyodysenteriae were detected by analysis of agar plates exposed to live B hyodysenteriae-inoculated adult flies wandering and feeding on these plates for 20 min per day. In generational challenge inoculation studies, B hyodysenteriae was detected in the adult emergent flies, and internal components of fly pupae on days 1-7 of the pupation period, after being inoculated with B hyodysenteriae as larvae. Five-week-old conventional mice (C3H) that consumed 2 meals of B hyodysenteriae-infected flies remained negative for B hyodysenteriae throughout the next 10 days. The results indicated that pathogenic Brachyspira sp have a limited ability to internally colonise likely insect vectors and do not readily transmit infection to mice. However, the insect vectors analysed were demonstrably capable of mechanical carriage and likely on-farm involvement in consequence.
(Copyright © 2022 Elsevier B.V. All rights reserved.)
Databáze: MEDLINE
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