Association of different microbes and pathogenic factors in cases of infectious bovine keratoconjunctivitis in cattle from Eastern Kazakhstan

Marat Kuibagarov; Elmira Abdullina; Anara Ryskeldina; Bolat Abdigulov; Asylulan Amirgazin; Alexandr Shevtsov; John A Angelos

doi:10.14202/vetworld.2023.1833-1839

Association of different microbes and pathogenic factors in cases of infectious bovine keratoconjunctivitis in cattle from Eastern Kazakhstan

Vet World. 2023 Sep;16(9):1833-1839. doi: 10.14202/vetworld.2023.1833-1839. Epub 2023 Sep 14.

Authors

Marat Kuibagarov¹, Elmira Abdullina², Anara Ryskeldina¹, Bolat Abdigulov¹, Asylulan Amirgazin¹, Alexandr Shevtsov¹, John A Angelos³

Affiliations

¹ National Center for Biotechnology, Astana, 010000, Kazakhstan.
² Department of Veterinary and Agricultural Management, Shakarim University, Semey, 071412, Kazakhstan.
³ Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California 95616, USA.

Abstract

Background and aim: Infectious bovine keratoconjunctivitis (IBK) causes a significant economic loss to cattle industries in many countries, including Kazakhstan. Although Moraxella bovis is recognized as an etiologic agent of IBK, other bacterial and viral agents have been suspected to play a role in the pathogenesis of this disease. This study aimed to evaluate samples collected from the eyes of IBK-affected cattle in Eastern Kazakhstan at different stages of IBK for the presence of Mor. bovis, Moraxella bovoculi, Mycoplasma bovis, Mycoplasma bovoculi, and Bovine Herpes Virus Type 1 (BHV-1) and to characterize Mor. bovoculi pilA gene sequence diversity from Mor. bovoculi positive samples.

Materials and methods: Individual ocular swabs (n = 168) were collected from cattle that had clinical signs of IBK during the summer of 2022 on farms in the Abay region of Kazakhstan. Eye lesion scores (1, 2, and 3) were assigned depending on the degree of ocular damage. Infectious bovine keratoconjunctivitis-associated organisms were detected using a multiplex real-time polymerase chain reaction assay. The Mor. bovoculi pilA gene was sequenced from Mor. bovoculi positive samples.

Results: Mycoplasma bovis and BHV-1 were not detected in any of the collected samples. Mycoplasma bovoculi was identified in the majority of samples overall, usually in mixed infection with Moraxella spp. Moraxella bovoculi was detected in 76.2% of animals and predominated in animals with eye lesion scores 2 and 3. Mycoplasma bovoculi was detected only in association with Mor. bovis and/or Mor. bovoculi in animals with eye lesion scores 2 and 3. Moraxella bovis was found in 57.7% of animals and was always identified in association with another organism. Sequencing of the pilA gene in 96 samples from Mor. bovoculi positive samples identified five PilA groups. The majority belonged to PilA group A. However, three new PilA groups were identified and designated PilA groups N, O, and P.

Conclusion: The results indicate a high prevalence of Myc. bovoculi and Mor. bovoculi in eyes of cattle with IBK on livestock farms in Eastern Kazakhstan. Additional novel Mor. bovoculi PilA groups were identified.

Keywords: Moraxella bovis; Moraxella bovoculi; Mycoplasma bovis; Mycoplasma bovoculi; bovine herpes virus; infectious bovine keratoconjunctivitis; multiplex real-time polymerase chain reaction.