Characterisation of the course of Mycoplasma bovis infection in naturally infected dairy herds

Abstract

Mycoplasma bovis causes bovine respiratory disease, mastitis, arthritis and otitis. The importance of M. bovis has escalated because of recent outbreaks and introductions into countries previously free of M. bovis. We characterized the course of M. bovis infection on 19 recently infected dairy farms over 24 months. Our objective was to identify diagnostic tools to assess the efficacy of control measures to assess low risk infection status on M. bovis infected farms. PCR assays and culture were used to detect M. bovis, and in-house and BioX ELISAs were used to follow antibody responses. Cows and young stock were sampled on four separate occasions, and clinical cases were sampled when they arose. On 17 farms, a few cases of clinical mastitis were detected, mostly within the first eight weeks after the index case. Antibodies detected by in-house ELISA persisted in the serum of cows at least for 1.5 years on all farms, regardless of the M. bovis infection status or signs of clinical disease or subclinical mastitis on the farm. Six out of 19 farms became low risk as the infection was resolved. Our results suggest that, for biosecurity purposes, regular monitoring should be conducted on herds by screening for M. bovis in samples from cows with clinical mastitis and calves with pneumonia, in conjunction with testing young stock by screening longitudinally collected nasal swabs for M. bovis and sequential serum samples for antibody against recombinant antigen.3

Detection of Mycoplasma bovis in Pneumonic Calves

“…Depending on the obtained results, the PCR technique was appeared as an excellent directly method in the diagnosis of Mycoplasma and principally M. bovis from pneumonic lungs, without the demands for culturing microorganism, which is accurate method and will reduce the consuming time and efforts. Many global studies supported the use of PCR instead of the culturing or together for diagnosis of Mycoplasma and particularly M. bovis [39][40][41][42][43][44][45] .…”

Mycoplasma bovis Infections—Occurrence, Diagnosis and Control

“…It was previously reported that M. bovis has the ability to spread worldwide to countries for a long time considered free of the pathogen because of the widespread international trade in cattle [ 2 , 23 , 24 ]. The first case of M. bovis infection in Finland was recorded relatively recently in 2012 in pneumonic calves.…”

“…In 2012–2015, 0.26% of Finnish dairy farms were M. bovis infected [ 2 ]. To date, it is estimated that only 0.8% of Finnish dairy herds were infected with M. bovis between 2012 and 2018 [ 23 ]. A two-year survey included 19 Finnish dairy farms previously free of M. bovis showed mastitis caused by M. bovis in over 89% of all farms tested; however, only a few clinical mastitis cases were seen.…”

Expression Profiles of Inflammation-related MicroRNAs in Mycoplasma bovis Infected Milk of Holstein-Friesian and Doğu Anadolu Kırmızısı Cows

“…Failure to detect subclinical mastitis promptly allows the infection to spread rapidly (Halasa et al, 2007;Hughes and Watson, 2018). Increasing evidence in recent years suggests that M. bovis is a major cause of severe mastitis infections (Vahanikkila et al, 2019;Murai and Higuchi, 2019;Josi et al, 2018) and that M. bovis is more frequently detected than other pathogens in subclinical mastitis (Al-Farha et al, 2017;Fox 2012;Nicholas et al, 2016). Therefore, the development of diagnostic methods that can detect subclinical mastitis at an early stage is important.…”

“…including staphylococci and streptococci, are responsible for the majority of mastitis cases. Recent studies reported that Mycoplasma bovis (M. bovis) caused mastitis in dairy cows (Rossetti et al, 2010;Wisselink et al, 2019;Appelt et al, 2019;Behera et al, 2018;Cai et al, 2005;Vahanikkila et al, 2019;Murai and Higuchi, 2019;Al-Farha et al, 2018;Al-Farha et al, 2017).…”