Dynamics of Mycoplasma bovis in Dutch dairy herds during acute clinical outbreaks.

Autor: Penterman PM; Department of Ruminant Health, GD Animal Health, PO Box 9, 7400 AA Deventer, The Netherlands. Electronic address: p.penterman@gdanimalhealth.com., Holzhauer M; Department of Ruminant Health, GD Animal Health, PO Box 9, 7400 AA Deventer, The Netherlands., van Engelen E; Department of Research and Development, GD Animal Health, PO Box 9, 7400 AA Deventer, The Netherlands., Smits D; Department of Ruminant Health, GD Animal Health, PO Box 9, 7400 AA Deventer, The Netherlands., Velthuis AGJ; Department Bacteriology, Host-Pathogen Interaction & Diagnostic Development, Wageningen BioVeterinary Research, PO Box 65, 8200 AB Lelystad, The Netherlands; Bovine Health Management, Aeres University of Applied Sciences, PO box 374, 8250 AJ, Dronten, The Netherlands.
Jazyk: angličtina
Zdroj: Veterinary journal (London, England : 1997) [Vet J] 2022 May-Jun; Vol. 283-284, pp. 105841. Date of Electronic Publication: 2022 May 11.
DOI: 10.1016/j.tvjl.2022.105841
Abstrakt: Mycoplasma bovis (M. bovis) can cause serious illness in cattle, presenting as arthritis and mastitis in dairy cows and pneumonia, arthritis and otitis media in calves. This study aimed to provide insight into the dynamics of M. bovis within dairy herds, experiencing an acute outbreak in dairy cows. Twenty farms were followed with laboratory testing of suspected dairy cows. Each outbreak farm was sampled five times, at 2-3 week intervals, sampling blood and milk and conjunctival fluid from clinically suspected dairy cows and healthy animals from three different age groups: dairy cows, young stock (7-24 months) and calves (1-6 months). Additionally, bulk tank milk was sampled every visit and environmental samples were taken on the first and last visits. The presence of M. bovis was tested by evaluating antibody titres in blood, bacterial DNA in conjunctival fluid and environmental samples and viable bacteria in milk samples. All data were analysed using logistic regression models, corrected for repeated sampling and within-herd correlation. Sixty percent (12/20) of the herds showed a combination of arthritis and mastitis, while other herds experienced only clinically mastitis (3/20) or arthritis (5/20). From the time an outbreak was confirmed, M. bovis infection was not only present in dairy cows, but also in young stock and calves (80% of the farms). Laboratory tests also confirmed the presence of M. bovis in healthy animals. The M. bovis PCR levels of calves and young stock were highly correlated at all visits (r total = 0.81, P < 0.01). Furthermore, M. bovis was present in the environment of the animals. At the end of the 3-month study period, none of the 20 clinical outbreak farms were M. bovis-'negative', based on laboratory testing, although hardly any clinical cases were observed at that time.
(Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)
Databáze: MEDLINE
Externí odkaz: