Possible transmission of Sarcoptes scabiei between herbivorous Japanese serows and omnivorous Caniformia in Japan: a cryptic transmission and persistence?

Abstract

Background Two transmission patterns of Sarcoptes scabiei in host mammal communities have been reported based on microsatellite-level genetic studies in the last two decades. While one involves restrictions among different host taxa, the other is associated with predator–prey interactions between different host taxa. In contrast to these observations, the present study reports a possible irregular case of transmission of S. scabiei between herbivorous Japanese serow and omnivorous Caniformia mammals in Japan, though under very weak predator–prey relationships. Methods DNA from 93 Sarcoptes mites isolated from omnivorous Caniformia (such as the domestic dog, raccoon dog, raccoon and Japanese marten), omnivorous Cetartiodactyla (wild boar) and herbivorous Cetartiodactyla (Japanese serow) in Japan were analyzed by amplifying nine microsatellite markers. Principal components analyses (PCA), Bayesian clustering analyses using STRUCTURE software, and phylogenetic analyses by constructing a NeighborNet network were applied to determine the genetic relationships among mites associated with host populations. Results In all the analyses, the genetic differentiation of Sarcoptes mites from wild boars and Japanese serows was observed. Conversely, considerably close genetic relationships were detected between Caniformia-derived and Japanese serow-derived mites. Because the predator–prey interactions between the omnivorous Caniformia and herbivorous Japanese serow are quite limited and epidemiological history shows at least a 10-year lag between the emergence of sarcoptic mange in Japanese serow and that in Caniformia, the transmission of S. scabiei from Caniformia to Japanese serow is highly suspected. Conclusions The close genetic relationships among mites beyond Host–taxon relationships and without obvious predator–prey interactions in Caniformia and Japanese serow deviate from previously reported S. scabiei transmission patterns. This type of cryptic relationship of S. scabiei populations may exist in local mammalian communities worldwide and become a risk factor for the conservation of the remnant and fragmented populations of wild mammals. Electronic supplementary material The online version of this article (10.1186/s13071-019-3630-5) contains supplementary material, which is available to authorized users.

First description of sarcoptic mange in an Iberian hare (Lepus granatensis)

“…Descriptive genetic analysis revealed an evident deficiency in the observed heterozygosity and allelic richness, confirming the results of previous molecular investigations on Sarcoptes mite populations ( Rasero et al., 2010 ; Gakuya et al., 2011 ; Matsuyama et al., 2019 ; Rudd et al., 2020 ; Moroni et al., 2021 ). Moreover, the low number of private alleles indicates a reduced genetic divergence and high gene flow between mite populations analyzed in this study.…”

“…In the past decade, microsatellite (Mst) markers have been widely used in S. scabiei epidemiological and population genetic investigations ( Rasero et al., 2010 ; Gakuya et al., 2011 ; Matsuyama et al., 2019 ; Rudd et al., 2020 ; Moroni et al., 2021 ) and in forensic analyses ( Alasaad et al., 2012 ). In the present study, ten Msts were used to molecularly type Sarcoptes mites derived from a free-ranging Iberian hare and trace the possible source of the infection.…”

Sarcoptic mange: An emerging panzootic in wildlife

“…Even though S. scabiei is categorized as a multi-host parasite, there is still debate concerning host specificity (Arlian et al, 1988;Fazal et al, 2016;Matsuyama et al, 2019), which could be an important baseline to predict its virulence in novel hosts and explore potential cross-species transmission dynamics. Our understanding of the panzootic (i.e.…”

“…Previous studies have suggested that sarcoptic mange could represent a threat for wildlife, considering its potential severity, morbidity, the wide range of host species affected and its global distribution (Gortázar et al., 2007; Tompkins et al., 2015). Even though S. scabiei is categorized as a multi‐host parasite, there is still debate concerning host specificity (Arlian et al., 1988; Fazal et al., 2016; Matsuyama et al., 2019), which could be an important baseline to predict its virulence in novel hosts and explore potential cross‐species transmission dynamics. Our understanding of the panzootic (i.e.…”

Association of sarcoptic mange with kinship and habitat use in raccoon dogs (<i>Nyctereutes procyonoides</i>)

“…Therefore, contact transmission between raccoon dogs and domestic dogs is a real threat. Other studies reported close genetic relationships among mites of wild mammals in Japan [7,9]. Raccoon dogs and other animals may induce S. scabiei transmission, increasing the risk of epizootic sarcoptic mange.…”