Eradication of endemicBrachyspira pilosicoliinfection from a farrowing herd: a case report

Abstract

Brachyspira pilosicoli and B. innocens were isolated repeatedly from a herd of 60 sows which mostly produced feeder pigs but also raised some fattening pigs. Postweaning diarrhea had been a severe problem in this herd for years. The B. pilosicoli eradication plan was based on the general guidelines for elimination of B. hyodysenteriae, with some modifica-tions. The eradication measures were run in August 1997. In-feed medication with 200p.p.m. tiamulin lasted for 18–30 days, depending on the age group. The piggery unit was emptied, cleaned, disinfected and dried, and all worn surfaces were repaired. The animals were removed to temporary sheds situated 0–100m from the piggery unit. Only the sows and the boar returned to the piggery unit. All other pigs were sold from the sheds within 3 months after the eradication. Immediately after the eradication, the clinical postweaning diarrhea disappeared. The success of the program was monitored four times bacteriologically, and the last control sampling was in December 1999, 7 months after the total withdrawal of antimicrobial feed additives. The primary cultures from the last three samplings were also analysed with B. pilosicoli-specific PCR. All the samples were negative for B. pilosicoli. However, B. innocens could be isolated from each batch of samples. The analysis of B. inno-cens isolates by pulsed-field gel electrophoresis indicated that at least one genotype persisted in the herd. The clinical and laboratory findings suggest that the eradication of B. pilosicoli had succeeded in this herd

EMA and EFSA Joint Scientific Opinion on measures to reduce the need to use antimicrobial agents in animal husbandry in the European Union, and the resulting impacts on food safety (RONAFA)

“…A programme of swine dysentery eradication, including introduction of a strict biosecurity regime to prevent transmission and focus on effective treatment of disease carriers to eliminate the spread of the organism, combined with thorough cleaning and disinfecting of all surrounding areas to prevent reinfection has been successful, without depopulating the whole farm, when carefully conducted (Fossi et al, 2001;Stojanov et al, 2015) or when medicated early weaning can be used (Meszaros et al, 1985). It is debateable whether eradication programmes that involve prolonged mass treatment of animals with antimicrobials are acceptable, especially as some strains of B. hyodysenteriae that are resistant to all permitted therapeutic options are emerging and depopulation-repopulation options are available (Aarestrup et al, 2008).…”

The Spirochete Brachyspira pilosicoli, Enteric Pathogen of Animals and Humans

“…pilosicoli has been eradicated from a 60-sow pig herd by treatment of all animals with the antimicrobial tiamulin followed by relocation of the breeding herd, thorough cleaning and disinfection of the original premises, and then returning the adult animals to the farm (227). This protocol would be more difficult to follow in larger herds, and the existence of reservoir hosts such as wild birds and rodents presents an ongoing threat of reintroduction.…”

Molecular epidemiological study of Brachyspira pilosicoli in Finnish sow herds

“…We have shown that the eradication of B. pilosicoli in Finnish sow herds is possible in certain cases [11]. For the assessment of policy with regard to chronic B. pilosicoli infections in sow herds, improved knowledge about the epidemiology of this organism in Finnish swine herds is needed.…”