Development of a multilocus sequence typing scheme for intestinal spirochaetes within the genus Brachyspira

The purpose of this study was to evaluate a multilocus sequence typing (MLST) scheme for intestinal spirochaetes of the genus Brachyspira. Eight loci mainly coding for enzymes previously used in multilocus enzyme electrophoresis analysis of Brachyspira species were examined in 66 Brachyspira field isolates and type/reference strains. The isolates and strains were recovered from pigs, birds, dogs and a mouse and originated from seven European countries, the USA and Canada. Forty-six isolates represented recognized Brachyspira species and 20 represented provisionally designated species or isolates that have not been classified. Only two loci gave PCR products for all 66 strains and isolates, but amplicons for seven loci were obtained for 44 of the isolates. Sequences for each locus had a DNA allelic variation of 30-47 and an amino acid allelic variation of 14-47 that gave rise to the same number of sequence and amino acid types (58) for the strains and isolates studied. A population snapshot based on sequence and amino acid types showed a close phylogenetic relationship amongst the porcine isolates from the same geographical regions, and indicated a close evolutionary relationship between isolates recovered from pigs and mallards. A general concordance was obtained between the MLST groupings and classifications based on culture and biochemical tests, 16S rDNA sequence analysis and random amplified polymorphic DNA analysis. This is a first step towards establishing an MLST system for use in identifying Brachyspira species and determining relationships between individual strains and species in the genus

Northern fowl mite (Ornithonyssus sylviarum) in Sweden

Haematophagous mites were collected from the vent region and plumage of chickens in six hobby flocks of ornamental breeds in Sweden, one of which included turkeys. Soiled vent skin and feathers, dermatitis, hyperkeratosis, skin necroses and ulcers were observed in 12 necropsied birds from two of the flocks. The mites were identified as the northern fowl mite Ornithonyssus sylviarum (Mesostigmata: Macronyssidae). This was supported by sequence analysis of a 642-bp region in the mitochondrial cytochrome oxidase subunit 1 (COI) gene (COI) in mites collected from five flocks, which showed 97–99% sequence similarity to O. sylviarum by blast analysis. Pairwise sequence comparisons revealed nucleotide variations in the range of 0–2.8%, whereas amino acid sequences were highly conserved. This paper represents one of very few records of O. sylviarum in European poultry, and is the first to report COI sequence data for O. sylviarum from poultry in Europe

A follow-up on the Swedish roundworm control program: strengths and weaknesses

SUMMARY: Poultry roundworms have re-emerged in laying hens in many European countries due to the increase in noncaged housing. This is worrying because, at high parasite loads, Ascaridia galli can impact birds' welfare, health, and productivity. Worm control is therefore an important aspect of the successful management of the egg production industry. In 2009, the Swedish Egg Association initiated a voluntary control program to tackle the problem and reduce the appearance of worms in table eggs by encouraging producers to submit fecal samples for analysis. Since the start of the program, its data have never been thoroughly explored. Moreover, after more than a decade of challenges, our understanding of how egg producers perceive worm infection is still inadequate. This study was therefore designed to address these issues. The research data in the present study are drawn from 2 sources. First, through the control program and second, through an online survey. We have summarized the control program's achievements and discussed its findings and limitations. Although this work contributes to existing knowledge of roundworm control in laying hens in general, it also identifies gaps in knowledge. In conclusion, the control program can be improved by incorporating more strategic sampling and utilizing well-suited diagnostic tools for better assessment of infection status. It is equally important to educate producers on anthelmintics (AH) use and the development of resistance