Résumé
Objective To compare the efficiency of multiple etiological techniques for detection of Schistosoma japonicum infections in wild mice, so as to provide technical supports to assessment of schistosomiasis transmission risk. Methods Wild mice were captured with baited traps at night in Oncomelania hupensis snail-infested settings in schistosomiasis-endemic foci of Anhui Province from October to November, 2022. S. japonicum infections were detected in wild mice using microscopy of mouse liver tissues, microscopy of mouse mesenteric tissues, microscopy of mouse liver tissue homogenates, miracidial hatching test of mouse liver tissue homogenates, Kato-Katz technique and miracidial hatching test of mouse stool samples alone and in combinations. Identification of S. japonicum eggs or miracidia by any of these six assays was defined as an infection. The sensitivity of six assays alone or in combinations was compared for detection of S. japonicum infections in wild mice. Results A total of 1 703 wild mice were captured, with 366 wild mice detected positive for S. japonicum (21.49%). There were significant differences in the prevalence of S. japonicum infections in wild mice by six assays (Q = 529.33, P < 0.001) and in the sensitivity of six assays for detection of S. japonicum infections in wild mice (χ2 = 527.78, P < 0.001). In addition, the combination of microscopy of mouse liver tissues and mesenteric tissues, combination of microscopy of mouse liver tissues and liver tissue homogenates and combination of microscopy of mouse liver tissues, microscopy of mesenteric tissues, microscopy of liver tissue homogenates and Kato-Katz technique showed 86.61%, 87.16% and 97.27% sensitivities for detection of S. japonicum infections in wild mice, respectively. Conclusions Diverse etiological assays show various efficiencies for detection of S. japonicum infections in wild mice. Combination of microscopy of mouse liver tissues and microscopy of mesenteric tissues, and combination of microscopy of mouse liver tissues and microscopy of liver tissue homogenates are potential approaches for field detection of S. japonicum infections in wild mice.
Résumé
Objective To investigate the prevalence of Schistosoma japonicum infection in wild mice in Shitai County, Anhui Province, so as to provide insights into precise control of the source of S. japonicum infections. Methods Wild mice were captured using the trapping method for three successive nights at snail-infested settings from Jitan Village of Jitan Township, and Shiquan Village and Xibai Village of Dingxiang Township, Shitai County, Anhui Province in June and October, 2018. All trapped wild mice were sacrificed and liver and mesenteric vein specimens were collected for detection of S. japonicum eggs using microscopy, while the fecal samples in mouse intestines were collected for identification of S. japonicum infections using Kato-Katz technique. In addition, the population density of trapped wild mice was estimated and the prevalence of S. japonicum infection was calculated in trapped wild mice. Results A total of 376 wild mice were trapped from three villages in Shitai County. The population density of trapped wild mice was 9.1% (376/4 124), and the prevalence of S. japonicum infection was 24.2% (91/376) in trapped wild mice. The highest prevalence of S. japonicum infection was detected in Shiquan Village of Dingxiang Township (30.1%), and the lowest prevalence was seen in Xibai Village of Dingxiang Township; however, there was no significant difference in the prevalence of S. japonicum infection in trapped wild mice among three villages (χ2= 4.111, P > 0.05). In addition, there was no significant difference in the prevalence of S. japonicum infection in wild mice captured between on June (26.8%, 34/127) and October (22.9%, 57/249) (χ2 = 0.690, P = 0.406). The trapped wild mice included 6 species, including Rattus norvegicus, Niviventer niviventer, R. losea, Apodemus agrarius, Mus musculus and N. coning, and the two highest prevalence of S. japonicum infection was detected in R. losea (34.9%, 22/63) and R. norvegicus (31.2%, 44/141). Conclusions The prevalence of S. japonicum infections is high in wild mice in Shitai County, and there is a natural focus of schistosomiasis transmission in Shitai County.
Résumé
Laboratory inbred mice are used widely and commonly in biomedical research, but inbred mice do not have a big enough gene pool for the research. In this study, genetic and morphometric analyses were performed to obtain data on the characteristics of a newly developing inbred strain (KWM/Hym) captured from Chuncheon, Korea. All of five Korean wild male mice have the zinc-finger Y (ZfY) gene. Also, all of 19 Korean wild mice used in this analysis have the AKV-type murine leukemia virus gene, indicating that Korean wild mice might be Mus musculus musculus. To identify the genetic polymorphism in KWM/Hym, SNP analysis was performed. In a comparison with 28 SNP markers, there was a considerable difference between KWM/Hym and several inbred strains. The homogeneity between KWM/Hym and the inbred strains was as follows: C57BL/6J (39.3%), BALB/c AJic (42.9%), and DBA/2J (50%). KWM/Hym is most similar to the PWK/PhJ inbred strain (96.4%) derived from wild mice (Czech Republic). To identify the morphometric characteristics of KWM/Hym, the external morphology was measured. The tail ratio of male and female was 79.60±3.09 and 73.55±6.14%, respectively. KWM/Hym has short and agouti-colored hairs and its belly is white with golden hair. Taking these results together, KWM/Hym, a newly developing inbred mouse originated from wild mouse, might be use as new genetic resources to overcome the limitations of the current laboratory mice.