Comparison of multilocus sequence types found among recent North American isolates of Mycoplasma bovis from cattle, bison and deer

Authors: Register, Karen; JELINSKI, MURRAY - University Of Saskatchewan; WALDNER, MATTHEW - University Of Saskatchewan; Boatwright, Jr, William; Anderson, Tavis; HUNTER, DAVID - Turner Enterprises, Inc; HAMILTON, ROBERT - The Nature Conservancy; BURRAGE, PAT - Bluffton Veterinary Services; SHURY, TODD - Parks Canada, Banff National Park; BILDFELL, ROB - Oregon State University; WOLFF, PEREGRINE - Nevada Department Of Wildlife; MISKIMINS, DALE - South Dakota State University; DERSCHEID, RACHEL - Iowa State University; WOODBURY, MURRAY - University Of Saskatchewan

Submitted to: Journal of Veterinary Diagnostic Investigation
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/16/2019
Publication Date: 9/11/2019
Citation: Register, K.B., Jelinski, M., Waldner, M., Boatwright Jr, W.D., Anderson, T.K., Hunter, D., Hamilton, R., Burrage, P., Shury, T., Bildfell, R., Wolff, P., Miskimins, D., Derscheid, R., Woodbury, M. 2019. Comparison of multilocus sequence types found among North American isolates of Mycoplasma bovis from cattle, bison and deer, 2007-2017. Journal of Veterinary Diagnostic Investigation. 31(6):899-904. https://doi.org/10.1177/1040638719874848.
DOI: https://doi.org/10.1177/1040638719874848

Interpretive Summary: Mycoplasma bovis causes respiratory disease in cattle and is a frequent contributor to Bovine Respiratory Disease Complex. It has also recently become a major health problem in bison, causing diseases of the respiratory and reproductive tract. A previous genetic analysis of M. bovis isolates suggested that strains causing disease in bison may comprise a distinct family, different from the family of strains that causes disease in cattle. However, all the bison isolates so far evaluated were obtained between 2007 and 2014, while only ~20% of available cattle isolates originated during that timeframe, with only one from North America. The goal of our study was to compare a more uniform set of isolates, all from North America and all collected during the same span of time, so that we can more clearly understand whether North American strains recently circulating in different animal hosts are truly unique from one another. Our study included a total of 307 isolates, all obtained between 2007 and 2017, with 209 from cattle (31 from the United States and 178 from Canada), 96 from bison (53 from the United States and 43 from Canada) and one isolate each from a white-tailed deer and a mule deer (both from the United States). Isolates were evaluated using a technique known as multilocus sequence typing, which compares the DNA sequence from a small group of specially selected genes. Each unique DNA sequence is defined as a different sequence type, or ST. We found a total of 49 different STs among the isolates we examined, with 39 found exclusively in cattle and five found exclusively in bison. Four STs are shared between isolates from both bison and cattle, while one ST was found in cattle and in a white-tailed deer. The mule deer isolate could not be typed because it is missing one of the genes used to assign STs. These data reveal that a few strains of M. bovis circulate in both bison and cattle, but most strains are unique to the host in which they are found. This information may be of benefit in efforts to develop more efficacious, host-specific vaccines, since the choice of strains to be used for vaccine production can be specifically tailored to match those found most frequently in the host for which the vaccine is being produced.

Technical Abstract: Prior multilocus sequence typing (MLST) studies reported that Mycoplasma bovis isolates from North American bison possess sequence types (STs) different from those found among cattle. However, the bison isolates evaluated were obtained in 2007 or later, as compared to only ~20% of the available cattle isolates, with only one from North America. Our goal was to compare STs of additional, contemporary, North American cattle isolates with those from bison, as well as two isolates from North American deer, all originating during the same timeframe, to more definitively assess potential strain-related host specificity and expand our understanding of the genetic diversity of M. bovis. From 307 isolates obtained between 2007 and 2017 (209 from cattle, 96 from bison and two from deer), we identified 49 STs, 39 of which were found exclusively in cattle and five exclusively in bison. Four STs are shared between isolates from bison and cattle, while one ST was found in cattle and in a deer. An MLST-based phylogeny including the 155 STs thus far defined from a global collection of isolates for which MLST data are publically available reveals that STs found in bison fall within several divergent lineages that include STs found exclusively in cattle.