Hemoplasmas Are Endemic and Cause Asymptomatic Infection in the Endangered Darwin’s Fox (Lycalopex fulvipes)

Abstract

Mycoplasma haemocanis is prevalent in the endangered Darwin’s fox (Lycalopex fulvipes) in its main stronghold, Chiloé Island (Chile). The origin of the infection, its dynamics, its presence in other fox populations and the potential consequences for fox health remain unexplored. For 8 years, hemoplasmal DNA was screened and characterized in blood from 82 foxes in Chiloé and two other fox populations and in 250 free-ranging dogs from Chiloé. The prevalence of M. haemocanis in foxes was constant during the study years, and coinfection with “Candidatus Mycoplasma haematoparvum” was confirmed in 30% of the foxes. Both hemoplasma species were detected in the two mainland fox populations and in Chiloé dogs. M. haemocanis was significantly more prevalent and more genetically diverse in foxes than in dogs. Two of the seven M. haemocanis haplotypes identified were shared between these species. Network analyses did not show genetic structure by species (foxes versus dogs), geographic (island versus mainland populations), or temporal (years of study) factors. The probability of infection with M. haemocanis increased with fox age but was not associated with sex, season, or degree of anthropization of individual fox habitats. Some foxes recaptured years apart were infected with the same haplotype in both events, and no hematological alterations were associated with hemoplasma infection, suggesting tolerance to the infection. Altogether, our results indicate that M. haemocanis is enzootic in the Darwin’s fox and that intraspecific transmission is predominant. Nevertheless, such a prevalent pathogen in a threatened species represents a concern that must be considered in conservation actions. IMPORTANCE Mycoplasma haemocanis is enzootic in Darwin’s foxes. There is a higher M. haemocanis genetic diversity and prevalence in foxes than in sympatric dogs, although haplotypes are shared between the two carnivore species. There is an apparent tolerance of Darwin’s foxes to Mycoplasma haemocanis.

Widespread Infection with Hemotropic Mycoplasmas in Free-Ranging Dogs and Wild Foxes Across Six Bioclimatic Regions of Chile

“…First, only the 16S rRNA gene was sequenced here, what prevents us to distinguish between Mhc and Mhf [ 39 ]. Nevertheless, in a recent study on Chiloé Island in Southern Chile, Di Cataldo et al [ 11 ] confirmed by the sequencing of a portion of the RNase P gene that all these infections in dogs and foxes corresponded to Mhc . Moreover, Mhf has never been found in dogs.…”

“…In second place, we did not evaluate the presence of possible Mhc - C Mhp coinfections. Although Soto et al [ 10 ] did not find coinfections with hemoplasmas in dogs from southern Chile, Di Cataldo et al [ 11 ] did confirm Mhc - C Mhp coinfections in Darwin’s foxes. Therefore, the prevalence of each species is probably underestimated.…”

“…Network analyses containing sequences of both foxes and dogs from each bioregion was performed to evaluate genetic Mhc / Mhf and C Mhp diversity between host species in each bioregion. Finally, to assess hemoplasma genetic variability and structure in Chile, haplotype networks were performed between our hemoplasma sequences and those from the other two previously published studies in canids of Chile that included Darwin’s foxes and dogs [ 10 , 11 ].…”

“…Information about the presence and distribution of these agents in Chile is scarce. DNA of both Mhc and C Mhp have been reported in dogs from southern Chile [ 10 , 11 ]. Both agents have also been detected in a wild canid, the endangered Darwin’s fox ( Lycalopex fulvipes ) [ 11 , 12 ].…”

“…DNA of both Mhc and C Mhp have been reported in dogs from southern Chile [ 10 , 11 ]. Both agents have also been detected in a wild canid, the endangered Darwin’s fox ( Lycalopex fulvipes ) [ 11 , 12 ]. In that study, Di Cataldo et al [ 11 ] reported that Mhc was shared among dogs and foxes, but intraspecific transmission was predominant in the fox population.…”