Mycoplasma bovigenitalium infections

International Common Names

• English: chromic seminal vesiculitis; infertility; Mycoplasma bovigenitalium mastitis; vulvovaginitis

Mycoplasma bovigenitalium

Mycoplasma bovigenitalium, first characterized by Freundt (1955), is mostly found in the reproductive tract of cattle and buffaloes, but has also been isolated from pneumonic, arthritic and mastitic cattle and aborted foetuses (Ruhnke, 1994). There have been isolations of this mycoplasma, previously unclassified and known as mycoplasma ovine/caprine serogroup 11, but shown to be M. bovigenitalium (Nicholas et al., 2008), which causes similar reproductive problems in small ruminants (Wessels et al., 2001). Although experimental infections show it is capable of inducing pneumonic lesions in gnotobiotic calves (Gourlay et al., 1979), evidence is still lacking that it is a major pathogen and many of its reported pathogenic properties may be the result of undetected ureaplasmas. Phylogenetically, M. bovigenitalium belongs to the M. fermentans group based on 16S ribosomal gene sequence analysis, showing a very close similarity to M. californicum. Its genome is 862,247 base pairs, coding for 677 genes and it has a G+C content of 28.96% (Manso-Silván et al., 2013).

mammary gland diseases of large ruminants
mammary gland diseases of small ruminants
reproductive diseases of large ruminants
reproductive diseases of small ruminants
respiratory diseases of large ruminants
respiratory diseases of small ruminants

Mastitic lesions caused by M. bovigenitalium are of a purulent character early on, followed by more prominence of the interstitial tissue. Affected seminal vesicles are enlarged and when sectioned, brownish with decreased secretions (Ross, 1993). Respiratory disease associated with M. bovigenitalium consists of cranioventral consolidation of the lungs although it is not possible to verify whether this is the result of infection with this mycoplasma; more likely tissue damage is caused by bacteria or other mycoplasmas like Mycoplasma bovis. Experimental infection of gnotobiotic calves with M. bovigenitalium produced a subclinical cuffing type pneumonia (Gourlay et al., 1979)

Lesions due to M. bovigenitalium were seen in experimental models of the buffalo oviduct (Varsha et al., 1996), hamster tracheal (Kumar et al., 1992) and rabbit fallopian tube organ cultures (Singh et al., 1991) suggesting a direct pathogenic role for this mycoplasma.

Mastitis was produced in all cows experimentally infected via the udder with M. bovigenitalium; interestingly one cow also developed arthritis although Bacillus cereus was also isolated (Roberts, 1968). The mycoplasma persisted in the udder for at least 18 weeks. Only a small number of the bulls experimentally infected with M. bovigenitalium via the prepuce showed mild inflammatory lesions of the genital tract although mycoplasmas were recovered at various times from most animals (Kreusel et al., 1989). Experimental infections of the ovine mammary gland with M. bovigenitalium resulted in pathogenic effects including high milk cell counts and mycoplasma excretion leading in some cases to subclinical infections (Ball, 1990). Gourlay et al. (1979) showed that, when given intratracheally to gnotobiotic calves, M. bovigenitalium colonized the lungs and induced pneumonic lesions, producing microscopic cuffing lesions.

M. bovigenitalium is commonly found in semen samples or sheath washings from cattle, often along with Acholeplasma laidlawii, ureaplasmas and Mycoplasma bovis (Jasper, 1981; Ball, 1990; Eder-Rohm, 1996). It has been associated with occasional cases of epidymitis, orchitis, urethritis and seminal vesiculitis leading to pain on ejaculation or following palpation and may impair spermatozoa motility (Ross 1993; Ruhnke 1994). Thiede et al. (2002) detected antibodies to M. bovigenitalum in Polish free-living European Bison that had balanoposthitis. Experimental insemination infections with spiked semen have shown that it can be isolated easily from washed embryos where it forms a close association with the surface of zona pellucida, intact embryos and sperm cells (Bielanski et al., 2000). Furthermore officially recommended antibiotics appear to be ineffective in eliminating this mycoplasma from embryos.

Antibodies to M. bovigenitalium have been detected more frequently in cattle with reproductive disorders than in healthy cattle (Ashwani and Garg, 1996; Garg et al., 1999; Petit et al., 2008). Ghanem et al. (2013) detected M. bovigenitalium in 31 of 418 uterine swabs and concluded that M. bovigenitalium infection in the uterus might be associated with recent dystocia and with cytologic endometritis in postpartum dairy cows. M. bovigenitalium was isolated from dairy herds with vulvovaginitis and infertility though less frequently than ureaplasmas (Reid et al., 1989). In an outbreak of granulomatous vulvitis in feedlot heifers, M. bovigenitalium was isolated from affected animals along with bovine herpesvirus type 1, Moraxella bovis and Mycoplasma bovis suggesting a multifactorial aetiology (Gilbert and Oettlé, 1990). More recently Lysnyansky et al. (2009) identified M. bovigenitalium and Mycoplasma canadense from outbreaks of granulopapular vulvovaginitis in dairy cattle in Israel.

M. bovigenitalium, like M. bovis and M. californicum, is commonly isolated from mastitic milk and udder secretions (Jackson and Boughton, 1991; Baumgärtner, 1999). It was first isolated in the UK in 1960 then later reported in a more severe form in the USA (Davidson and Stuart, 1960; Boughton, 1979). In one outbreak M. bovigenitalium was isolated from over 50% of a large dairy herd suffering clinical mastitis (Ahmed, 1987). In a possibly unusual case M. bovigenitalium was linked to the cause of septic arthritis of the tarsus and an infection affecting the mammary gland of a 7-week old calf.  This also demonstrated the potential role of calves in the epidemiological of mycoplasma mastitis (Roy et al., 2008).

M. bovigenitalium was isolated from the respiratory tract of pneumonic calves by Laak et al. (1992) but not from healthy calves. Naglic et al. (1996) reported similar findings but also isolated M. bovigenitalium from eye swabs of the same cattle, some of which were showing conjunctivitis. Chima et al. (1995) isolated M. bovigenitalium from ewes with vaginal discharge and swollen vulvas. Reports of the biochemically and immunologically similar M. ovine/caprine serogroup 11 from identical clinical conditions (Poumarat et al., 1992; Nicholas et al., 1999; Wessels et al., 2001) suggests a very close relationship between this mycoplasma and M. bovigenitalium which has since been shown to be the same species (Nicholas et al., 2008).

M. bovigenitalium has been isolated from the joints of arthritic cattle but it is unlikely to be a primary cause (Mazzolini et al., 1993).

M. bovigenitalium and M. canis were isolated from dogs with and without reproductive disorders suggesting they played little role in disease (Zöldág et al., 1993).

It is not possible to estimate the economic costs of M. bovigenitalium as infections are usually multifactorial or under-reported.

There are no zoonotic or food safety implications of M. bovigenitalium infections.

For reproductive disorders, only two antibiotics, nourseothricin and lincospectin, of seven tested were effective in eliminating M. bovigenitalium and other mycoplasmas without adversely affecting the spermatozoa (Pfützner, 1989). An assessment of some photosensitive agents (haematopophyrin, a derivative of this and thiopronine) to disinfect bovine semen spiked with various microbial agents including M. bovigenitalium showed little effectiveness for mycoplasma at concentrations harmless to the sperm (Eaglesome et al., 1994). Kawai et al. (2013) carried out minimum inhibition concentrations on M. bovigenitalium isolates from mastitis cases in Japan and found the isolates to be sensitive to pirlimycin, danofloxacin, enrofloxacin, oxytetracycline, tilmicosin and tylosin, but not to kanamycin.