Detección Molecular de Mycoplasma spp. en felinos domésticos con FeLV atendidos en 15 clínicas veterinarias del Distrito Metropolitano de Quito, Ecuador, 2025-2026.

Abstract

Coinfection with hemoplasmas in domestic cats infected with Feline Leukemia Virus (FeLV) is a significant problem in veterinary medicine, as it can worsen the animals' clinical condition and promote hematological disorders, in addition to facilitating the presence of potentially zoonotic microorganisms. However, information on the molecular diversity of Mycoplasma spp. in FeLV-infected cats in Ecuador represents a significant knowledge gap at the epidemiological level. Based on this, the present study aimed to molecularly detect Mycoplasma spp. and phylogenetically characterize the circulating species in FeLV-positive domestic cats treated at 15 veterinary clinics in the Metropolitan District of Quito (2025-2026). Twenty samples from cats with a confirmed FeLV diagnosis were analyzed by 16S rRNA gene amplification, followed by Sanger sequencing and phylogenetic analysis. Overall, bacterial DNA was detected in 16 samples. Coinfection with Mycoplasma spp. was detected in 40% (8/20) of the evaluated individuals. Molecular sequencing identified Mycoplasma haemofelis as the predominant species, present in 25% (5/20) of the positive samples, while Candidatus Mycoplasma haematominutum was detected in 15% (3/20). BLASTn analysis confirmed the taxonomic identity of these sequences with identity percentages greater than 97%. Unexpectedly, several additional amplicon sequences (40% or 8/20) showed greater identity with bacteria of the genus Stenotrophomonas, mainly Stenotrophomonas maltophilia, suggesting possible coinfections of FeLV with other bacterial genera. Phylogenetic reconstruction based on the Kimura two-parameter evolutionary model with Gamma (K2+G) distribution generated consistent topologies using Maximum Parsimony and Maximum Likelihood methods. For this analysis, reference sequences obtained from the GenBank database were incorporated. These sequences were used to establish the phylogenetic relationship between the isolates obtained in this study and strains previously reported in Brazil, Malaysia, China, and other countries. These findings demonstrate the circulation of feline hemoplasmas in FeLV-positive cats in the Metropolitan District of Quito (DMQ) and highlight the importance of considering these coinfections in clinical diagnosis. Furthermore, they contribute to the understanding of the molecular epidemiology of these pathogens in Ecuador and support the development of surveillance and prevention strategies under the One Health approach.