Tuyakhov, M.
(2024).
The role of yeasts in etiology of canine otitis.
Scientific Reports of the National University of Life and Environmental Sciences of Ukraine,
20(2).
https://doi.org/10.31548/dopovidi.2(108).2024.015
The article presents the results of the study of the species composition of the microbiota of the skin surface of the auditory canal for otitis in dogs, in particular the results of the study of the fungal microbiota and the frequency of associations of pathogenic fungi with bacterial pathogens. Objective. Investigation of the ear microbiota in dogs with otitis with the aim of identifying microbial/fungal species composition and establishing the role of yeasts in the etiology of otitis, identifying possible associations of fungi and pathogenic staphylococci. Materials and methods. Experimental animals were dogs aged from 6 months to 10 years. During the period 2018-2020, 30 dogs of various breeds weighing 5-60 kg, of both genders, with otitis symptoms were examined. During the study, sampling of clinical material from affected animals, isolation of pathogen cultures on nutrient media, the study of their cultural properties and the determination of sensitivity to the corresponding drugs were carried out. As the research results showed, among the representatives of yeast fungi in the material isolated from dogs with otitis, Malassezia pachydermatis was most often isolated - 9 cases (30%). Representatives of Candida albicans were isolated in only 1 case (3.3%), so their clinical significance requires further study. These fungi could be extraneous contaminants. It should be noted that in 9 cases (30% of the number of cases of Staphylococcus aureus isolation) associations of S. aureus were observed with Malassezia pachydermatis fungi, in 6 cases (20%) associations of Staphylococcus pseudintermedius with Malassezia pachydermatis fungi were observed; in 5 cases (16.7%) – associations of S. aureus with gram-negative Proteus spp. Conclusions. 1. Among representatives of yeast fungi in the material isolated from dogs with otitis, M. pachydermatis was most often isolated – 9 cases (30%). 2. Representatives of C. albicans were isolated in only 1 case (3.3%), so their clinical significance requires further study. These agents could be extraneous contaminants. 3. It should be noted that in 9 cases (30% of the number of cases of S. aureus isolation) associations with M. pachydermatis fungi were observed, in 6 cases (20%) associations of S. pseudintermedius with M. pachydermatis fungi were observed; in 5 cases (16.7%) – associations of Malassezia with gram-negative Proteus spp.
dogs, microbiological investigation, nutrient media, skin microbiota, yeast fungi, otitis, fungal-microbial assocations, malassezia, sensitivity
[1] Miller, W., Griffin, C., & Campbell, K. (2013). Fungal and algal skin diseases. In Muller and Kirk’s small animal dermatology (pp. 243-252). St. Louis: Elsevier.
[2] Mauldin, E.A., Scott, D.W., Miller, W.H., & Smith, C.A. (1997). Malassezia dermatitis in the dog: a retrospective histopathological and immunopathological study of 86 cases (1990-1995). Veterinary Dermatology, 8(3), 191-202. doi: 10.1046/j.1365-3164.1997.d01-15.x.
[3] Guillot, J., et al. (1998). Importance des levures du genre Malassezia. Point Veterinaire, 29, 691-701.
[4] Scott, D.W. (1992). Bacteria and yeast on the surface and within non-inflamed hair follicles of skin biopsies from dogs with non-neoplastic dermatoses. Cornell Veterinarian, 82,379-386.
[5] Berger, D., Lewis, P., Schick, A., & Stone, R.T. (2012). Comparison of once-daily versus twice-weekly terbinafine administration for the treatment of canine Malassezia dermatitis – a pilot study. Veterinary Dermatology, 23(5),418-e79. doi: 10.1111/j.1365-3164.2012.01074.x.
[6] Bond, R., & Lloyd, D.H. (1998). The relationship between population sizes of Malassezia pachydermatis in healthy dogs and in Basset Hounds with M. pachydermatis-associated seborrhoeic dermatitis and adherence to canine corneocytes in vitro. In Advances in veterinary dermatology III (pp. 283-289). Boston: Butterworth-Heinemann.
[7] Guillot, J., Bensignor, E., Jankowski, F., Seewald, W., Chermette, R., & Steffan, J. (2003). Comparative efficacies of oral ketoconazole and terbinafine for reducing Malassezia population sizes on the skin of Basset Hounds. Veterinary Dermatology, 14, 153-157. doi: 10.1046/j.1365-3164.2003.00334.x.
[8] Greene, C.E. (2006). Cutaneous fungal infections (3rd ed.). In Infectious diseases of the dog and cat (pp. 602-606). Philadelphia: WB Saunders & Co.
[9] Guillot, J., et al. (1998). Importance des levures du genre Malassezia. Point Veterinaire, 29, 691-701.
[10] Nègre, A., Bensignor, E., & Guillot, J. (2009). Evidence-based veterinary dermatology: a systematic review of interventions for Malassezia dermatitis in dogs. Veterinary Dermatology, 20, 1-12. doi: 10.1111/j.1365-3164.2008.00721.x.
[11] Guillot, J., Bensignor, E., Jankowski, F., Seewald, W., Chermette, R., & Steffan, J. (2003). Comparative efficacies of oral ketoconazole and terbinafine for reducing Malassezia population sizes on the skin of Basset Hounds. Veterinary Dermatology, 14, 153-157. doi: 10.1046/j.1365-3164.2003.00334.x.
[12] Bond, R., & Lloyd, D.H. (1995). Evaluation of a detergent scrub technique for the quantitative culture of Malassezia pachydermatis from canine skin. Research in Veterinary Science, 58, 133-137. doi: 10.1016/0034-5288(95)90066-7.
[13] Bond, R. (2010). Superficial veterinary mycoses. Clinics in Dermatology, 28(2), 226-236. doi: 10.1016/j.clindermatol.2009.12.012.
[14] Bugden, D.L. (2013). Identification and antibiotic susceptibility of bacterial isolates from dogs with otitis externa in Australia. Australian Veterinary Journal, 91(1-2), 43-46.
[15] Griffin, C.E. (2010). Classifying cases of otitis externa the PPSP system. Proceedings of ESVD Workshop on Otitis St. Helens.
[16] Nambi, A.P. (2002). Malassezia dermatitis in dogs. Intas Polivet, 3, 202-205.
[17] Nardoni, S.M., Corazza, F., & Mancianti, F. (2008). Mancianti diagnostic, clinical features of animal malasseziosis. Parassitologia, 50(1-2), 81-83.
[18] Petrov, V.G., Mihaylov, I., Tsachev, G., Zhelev, P., & Marutsov, K. (2013). Otitis externa in dogs: Microbiology and antimicrobial susceptibility. Revista de Medicina Veterinaria, 164(1), 18-22.
[19] Reddy, C.B.K., & Kumari, K.N. (2015). Therapeutic management of Malassezia dermatitis in a Labrador retriever dog. International Journal of Livestock Research, 5(7), 105-109.
[20] Zamankhan, H., Malayeri, S., Jamshidi, T., & Zahraei, S. (2010). Identification and antimicrobial susceptibility patterns of bacteria causing otitis externa in dogs. Veterinary Research Communications, 34, 435-444.
[21] Bond, R., Morris, D.O., Guillot, J., Bensignor, E.J., Robson, D., Mason, K.V., Kano, R., & Hill, P.B. (2020). Biology, diagnosis and treatment of Malassezia dermatitis in dogs and cats Clinical Consensus Guidelines of the World Association for Veterinary Dermatology. Veterinary Dermatology, 31, 28-74. doi: 10.1111/vde.12809.
[22] Boone, J.M., Bond, R., Loeffler, A., Ferguson, E.A., & Hendricks, A. (2021). Malassezia otitis unresponsive to primary care: Outcome in 59 dogs. Veterinary Dermatology, 32(5), 441-119. doi: 10.1111/vde.12995.
[23] Lorek, A., Dennis, R., van Dijk, J., & Bannoehr, J. (2020). Occult otitis media in dogs with chronic otitis externa – magnetic resonance imaging and association with otoscopic and cytological findings. Veterinary Dermatology, 31, 146-153. doi: 10.1111/vde.12817.