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Background: The genus Rickettsia contains the lineages spotted fever group (SFG), typhus group (TG), and transitional group (TRG). The spotted fever group Rickettsia (SFGR) is transmitted by ticks. The tick species Dermacentor nuttalli is considered the main vector carrying SFGR in Inner Mongolia. Studying the genetic diversity and population structure of Rickettsia is essential for developing effective control strategies and predicting evolutionary trends of Rickettsia. Methods: In 2019 we collected 408 D. nuttalli in the Inner Mongolia Autonomous Region, detected the percentage of Rickettsia-positive specimens, and characterized the haplotypes. From the Rickettsia-positive ticks, the gltA and ompA genes were extracted, amplified, and sequenced. Results: Ten haplotypes of the gltA gene and 22 haplotypes of the ompA gene were obtained. The phylogenetic analysis showed that the haplotypes G1–G7 and G9 of the gltA gene cluster with Rickettsia raoultii, while G8 and G10 cluster with Rickettsia sibirica. Haplotypes O1–O15, O18 and O20–O22 of the ompA gene cluster with R. raoultii, while O16 and O19 cluster with R. sibirica. The average haplotype diversity was 0.3 for gltA and 0.7 for ompA. The average nucleotide diversity was greater than 0.05. Neutrality tests were nonsignificant for Tajima's D results and Fu's Fs results. The fixation index values (FST) showed that the degree of genetic differentiation between most sampled populations was small (FST < 0.05), whereas some populations showed a medium (FST > 0.05) or large (FST > 0.15) degree of differentiation. Analysis of molecular variance (AMOVA) revealed that the variation within populations was greater than that between populations. The mismatch analysis of Rickettsia showed double peaks. Conclusions: We found two Rickettsia spp. (R. raoultii and R. sibirica). The high genetic disparity of Rickettsia allows for easy adaption to different environments. Genetic differentiation between populations is small, and Rickettsia populations do not show a geographically differentiated structure. The high rates of retention and infection of Rickettsia in D. nuttalli together with the animal husbandry exchange in Inner Mongolia gradually led to the harmonization of genetic characteristics of Rickettsia across various regions. Overall, the significant genetic diversity and geographical structure of Rickettsia in D. nuttalli are critical for SFGR control. [ABSTRACT FROM AUTHOR]

Small mammals inhabiting temperate and arctic regions exhibit annual adaptive adjustments in physiology, anatomy, and behavior. No data on the physiology of Maximowicz's voles ( Microtus maximowiczii) are available at present. Here we examined the seasonal changes in body mass, food intake, thermogenic capacity, serum leptin and thyroid hormone levels in wild-captured individuals from Inner Mongolian grassland, China. We further examined the effects of photoperiod on these parameters. Energy intake, resting metabolic rate, nonshivering thermogenesis (NST), and serum tri-iodothyronine (T3) levels increased while serum leptin and body mass decreased in the cold seasons. Serum T3 levels were positively correlated with NST and uncoupling protein 1 (UCP1) contents in brown adipose tissue, and leptin levels were negatively correlated with energy intake and resting metabolic rate. Furthermore, laboratory data showed these changes could be induced by short photoperiod alone. Taken together, our results indicate that Maximowicz's voles can increase thermogenic capacity and energy intake to cope with cold stress. Serum leptin seems to be involved in the regulation of energy intake and changes in T3 level may be important for the variations in NST and/or UCP1. Short photoperiod can serve as a seasonal cue for the winter acclimatization of energy balance in free-living Maximowicz's voles. [ABSTRACT FROM AUTHOR]

Background: Ticks (Arthropoda, Ixodida), after mosquitoes, are the second most prevalent vector of infectious diseases. They are responsible for spreading a multitude of pathogens and threatening the health and welfare of animals and human beings. However, given the history of tick-borne pathogen infections in the Inner Mongolia Autonomous Region of China, surprisingly, neither the genetic diversity nor the spatial distribution of haplotypes within ticks has been studied., Methods: We characterized the haplotype distribution of Dermacentor nuttalli in four main pastoral areas of the Inner Mongolia Autonomous Region, by sampling 109 individuals (recovered from sheep) in April-August 2019. The 16S rRNA gene, cytochrome c oxidase subunit I (COI), and the internal transcribed spacer 2 region (ITS2) were amplified and sequenced from extracted DNA., Results: Twenty-six haplotypes were identified using 16S rRNA sequences, 57 haplotypes were identified with COI sequences, and 75 haplotypes were identified with ITS2 sequences. Among the three genes, total haplotype diversity was greater than 0.7, while total nucleotide diversity was greater than 0.06. Neutrality tests revealed a significantly negative Tajima's D result, while Fu's Fs was not significantly positive. Fixation index values (F ST ) indicated that the degree of genetic differentiation among some sampled populations was small, while for others it was moderate. Analysis of molecular variance (AMOVA) revealed that the variation within populations was greater than that among populations. The mismatch analysis of D. nuttalli exhibited double peaks., Conclusion: The genetic diversity of D. nuttalli populations in our region can likely adapt to different geographical environments, thereby leading to genetic diversity, and creating genetic differentiation among different populations. However, genetic differentiation is cryptic and does not form a pedigree geographical structure.

Objective: To perform pathological observation and etiological identification of specimens collected from dairy cows, beef cattle and dogs which were suspected of rabies in Inner Mongolia in 2011, and analyze their etiological characteristics., Methods: Pathological observation was conducted on the brain specimens of three infected animals with Hematoxylin-Eosin staining, followed by confirmation using immunofluorescence and nested RT-PCR methods. Finally, phylogenetic analysis was conducted using the virus N gene sequence amplified from three specimens., Results: Eosinophilic and cytoplasmic inclusion bodies were seen in neuronal cells of the CNS; and rabies non-characteristic histopathological changes were also detected in the CNS. The three brain specimens were detected positive. N gene nucleotide sequence of these three isolates showed distinct sequence identity, therefore they fell into different groups in the phylogenetic analysis. N gene in the cow and dog had higher homology with that in Hebei isolate, but that in the beef cattle had higher homology with that in Mongolian lupine isolate and Russian red fox isolate., Conclusion: Rabies were observed in the dairy cow, beef cattle and canine in the farm in Inner Mongolia, in 2011, which led to a different etiologic characteristics of the epidemic situation., (Copyright © 2014 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.)

Beta-globin gene cluster haplotype frequencies of 169 Khalkhs and 145 Buryats were estimated, and their characteristics were compared with those of Evenkis, Oroqens, Koreans, Japanese, and three Colombian Amerindian groups. The present study suggests that Colombian Amerindians diverged first from Asian populations and then Buryats diverged from other Asian populations.