RESUMEN
Due to its increasing occurrence in cattle farms in various countries, leading to significant economic losses in affected livestock, Salmonella enterica subspecies enterica serovar Dublin (S. Dublin) has become a highly investigated pathogen in cattle production. In Austria, there have been occasional human cases of S. Dublin as well as an increase in laboratory-confirmed cases in cattle, indicating the need for a screening programme to determine the current status in Austria. The aims of this study were, firstly, to determine the seroprevalence of S. Dublin in dairy herds through bulk milk screenings in two federal states (Salzburg, Tyrol) of Austria. Secondly, the study aimed to identify the infection status of the herds through individual animal and herd level detection, comparing microbiological, molecular and serological detection methods. The results of the study will allow the development of a sampling strategy for a surveillance programme in Austria. A total of 6973 dairy farms were tested through serological bulk milk screening. The seroprevalence for the federal state of Tyrol was 14.8â¯% and for Salzburg it was 18.2â¯%, resulting in an average seroprevalence of 16.5â¯%. At an individual animal level, 205 (11.3â¯%) animals tested positive for shedding of S. Dublin in the faeces through microbiological detection, and 268 (17.0â¯%) animals had positive values (ct value ≤ 38) by qPCR. The association between microbiological and molecular detection was statistically significant (p < 0.001), with a calculated kappa value of 0.65 ± 0.27 (p ≤ 0.001), assuming a substantial level of agreement. In 17 herds, where an individual animal tested positive for shedding of S. Dublin, environmental sampling and testing were carried out. At a herd level 16 (94.1â¯%) out of the 17 participating herds, tested positive for S. Dublin either microbiologically or by molecular assay in boot swab samples. Bulk milk samples from 14 out of the 17 participating herds were analysed for antibodies to S. Dublin and 12 samples (85.7â¯%) were positive. In total 111 (18.9â¯%) out of 587 blood samples tested positive for S. Dublin antibodies, demonstrating a statistically significant correlation (p < 0.001) both with microbiological (κ = 0.32 ± 0.49; p ≤ 0.001) and molecular (κ=0.23 ± 0.06; p ≤ 0.001) findings. It was possible to identify S. Dublin by culture from boot swabs in 14 (82.4â¯%) out of 17 herds and by molecular assay using qPCR in 15 (88.2â¯%) out of 17 herds, indicating a suitable sample type for screening on a herd level-basis for acute infections, but not for identifying chronic infections or asymptomatic carriers. Other environmental samples, such as sponge-sticks, are only suitable to a limited extent for the detection of S. Dublin. The results of this study demonstrate a moderate S. Dublin prevalence in dairy herds in the selected Austrian regions, signalling further screening and management programmes for the future.
Asunto(s)
Enfermedades de los Bovinos , Industria Lechera , Leche , Salmonelosis Animal , Animales , Bovinos , Austria/epidemiología , Salmonelosis Animal/epidemiología , Salmonelosis Animal/microbiología , Salmonelosis Animal/diagnóstico , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/microbiología , Enfermedades de los Bovinos/diagnóstico , Estudios Seroepidemiológicos , Femenino , Leche/microbiología , Salmonella/aislamiento & purificación , Heces/microbiología , Prevalencia , Monitoreo Epidemiológico/veterinariaRESUMEN
This study aimed to investigate the prevalence of Mycobacterium avium subsp. paratuberculosis (MAP) in small ruminants in Austria by testing 22,019 serum samples with ELISA for the presence of specific antibodies. Furthermore, detailed investigations in five MAP-infected goat herds were carried out by ELISA, qPCR and bacterial culture. The found animal-level apparent MAP seroprevalence was 2.0% for goats and 0.7% for sheep (calculated true prevalence 3.5% and 1.2%, respectively). Herd-level apparent MAP seroprevalence was 11.1% for goat herds and 8.9% for sheep flocks. Significant risk factors for seropositivity in goat herds were: herd size, animal trading, farmed as a dairy herd, Animal Health Service membership and cohabitation with farmed game. For sheep flocks, seroprevalence was significantly higher in flocks with animal trading and where cattle or goats were kept in the flock, respectively. The overall apparent within-herd MAP seroprevalence in the five goat farms investigated was 21.8% (11.7%-28.0%, calculated true seroprevalence 38.6%) and an overall rate of MAP shedding of 12.3% was detected (5.0%-24.7%). It was possible to identify MAP by culture using boot swab samples in each herd. The results indicated a moderate MAP infection rate in small ruminants in Austria.
RESUMEN
OBJECTIVE: In the study, the laboratory results of 150 bovine abortion cases from 2018 (January-September) are presented. MATERIAL AND METHODS: Depending on the submitted sample material and the requested examination, serological, bacteriological and/or molecular biological investigations were performed to detect abortion-causing pathogens which need or do not need to be notified in Austria. RESULTS: In addition to animal pathogens, the zoonotic pathogens Brucella melitensis and Salmonella Dublin were detected in 1 case each and Coxiella burnetii in 2 fetuses. CONCLUSION: The results show, that because of the zoonotic potential of some pathogens, care must be taken when handling abortion material to ensure that farmers, veterinary surgeons and laboratory staff are not at risk. Taking bovine brucellosis as an example, the reappearance of previously eradicated diseases has to be expected at any time. CLINICAL RELEVANCE: For detailed diagnostics, fetus with placenta and blood samples from the dam should be submitted to the laboratory. According to the extensive pathogen spectrum, investigation of abortion cases is laborious and time consuming.