Abstract Background Ticks are hematophagous arthropods capable of transmitting pathogens threatening human and animal health. The use of individual gene markers has limited phylogenetic studies of ticks, but the mitochondrial genome offers critical data for understanding phylogeny and molecular evolution. Results The mitogenomes of Dermacentor everestianus and Alveonasus sp. were assembled from Illumina 350 bp pair-end reads. In this study, we sequenced the complete mitochondrial genomes of Dermacentor everestianus and Alveonasus sp., which measured 16,413 bp and 14,545 bp, respectively. Both mitogenomes contained 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and 13 protein-coding genes (PCGs). Dermacentor everestianus has two similar insertions between tRNA-Phe and tRNA-Gln and between tRNA-Glu and ND1. The adenine + thymine (A + T) content was 78.68% for D. everestianus and 71.60% for Alveonasus sp. Dermacentor everestianus showed negative AT- and GC-skews, whereas Alveonasus sp. exhibited positive AT-skews and negative GC-skews. The nucleotide diversity (Pi) and nonsynonymous (Ka)/synonymous (Ks) mutation rate ratios indicated that NAD1 , COX1 , and COX3 were the most conserved genes, with COX1 showing the lowest evolutionary rate. Phylogenetic analysis was performed using maximum likelihood (ML) methods based on COI gene and 13 PCGs. The results revealed that D. everestianus belongs to the Ixodidae family, within the Dermacentor genus, while Alveonasus sp. should be classified as a separate evolutionary lineage within the Argasidae family. Conclusions These findings provide valuable insights into tick genetic variation, molecular classification, and evolutionary relationships, offering a foundation for future research in these areas.

Blastocystis sp. is a zoonotic protozoan that infects various animals, including plateau yaks. We conducted this study to compare the microbiota of Blastocystis sp.-positive and-negative yaks on the cold plateau. Fecal samples of Blastocystis sP. positive and negative yaks were assigned to BSP and CON groups and subjected to amplicon sequencing. A total of 2021402 (BSP) and 2702263 (CON) raw reads, and 1973301 (BSP) and 2625224 (CON) filtered reads, were obtained. Alpha diversity evaluation showed that Pielou (P<0.01), Shannon (P<0.01), and Simpson (P<0.05) in BSP yaks were significantly lower than in CON animals. Beta diversity analysis revealed significant differences in PCA (P<0.01), PCoA (P<0.01), NMDS (P<0.05), UPGMA, and Anosim (P<0.01) between the two yak groups. Microbiota biomarker analysis identified thirty-six distinguished genera including AsPergillus, Wallemia, CoPrinellus, Mucor, Sarocladium, Coniochaeta, and Anaeromyces between Blastocystis sp. positive and negative yaks. Our results unveil potential avenues for the development of effective therapies against Blastocystis sp.

Ticks are specialized ectoparasites that feed on blood, causing physical harm to the host and facilitating pathogen transmission. The genus Haemaphysalis contains vectors for numerous infectious agents. These agents cause various diseases in humans and animals. Mitochondrial genome sequences serve as reliable molecular markers, forming a crucial basis for evolutionary analyses, studying species origins, and exploring molecular phylogeny. We extracted mitochondrial genome from the enriched mitochondria of Haemaphysalis tibetensis and obtained a 14,714-bp sequence. The mitochondrial genome consists of 13 protein-coding genes (PCGs), two ribosomal RNA, 22 transfer RNAs (tRNAs), and two control regions. The nucleotide composition of H. tibetensis mitochondrial genome was 38.38 % for A, 9.61 % for G, 39.32 % for T, and 12.69 % for C. The A + T content of H. tibetensis mitochondrial genome was 77.7 %, significantly higher than the G + C content. The repeat units of H. tibetensis exhibited two identical repeat units of 33 bp in length, positioned downstream of nad1 and rrnL genes. Furthermore, phylogenetic analyses based on the 13 PCGs indicated that Haemaphysalis tibetensis (subgenus Allophysalis) formed a monophyletic clade with Haemaphysalis nepalensis (subgenus Herpetobia) and Haemaphysalis danieli (subgenus Allophysalis). Although the species Haemaphysalis inermis, Haemaphysalis kitaokai, Haemaphysalis kolonini, and Haemaphysalis colasbelcouri belong to the subgenus Alloceraea, which were morphologically primitive hemaphysalines just like H. tibetensis, these four tick species cannot form a single clade with H. tibetensis. In this study, the whole mitochondrial genome sequence of H. tibetensis from Tibet was obtained, which enriched the mitochondrial genome data of ticks and provided genetic markers to study the population heredity and molecular evolution of the genus Haemaphysalis.

Ticks serve as vectors and reservoirs for a variety of pathogens, including protozoa, bacteria, and viruses, that cause tick-borne diseases in both humans and livestock. Despite their widespread distribution, their genetic diversity and population structure in Xizang have not been thoroughly investigated. In this study, sheep ticks were identified from four counties by microscopy, followed by genetic analysis of Dermacentor everestianus populations in Xizang based on mitochondrial 16S rRNA and cytochrome oxidase subunit 1 (COI) gene sequences. D. everestianus was the predominant species and 16S rRNA gene sequence analysis revealed nine haplotypes with seven nucleotide variations, showing a mean haplotype diversity (Hd) of 0.505 and mean nucleotide diversity (Pi) of 0.00129. Similarly, the COI sequences revealed 28 haplotypes with 26 nucleotide variations, yielding a mean Hd of 0.828 and a mean Pi of 0.00279. Molecular variance analysis (AMOVA) indicated that most genetic variation occurs within populations. In addition, neutral test analyses suggested potential bottleneck events in the D. everestianus populations. The haplotype network had a star-like distribution with the common haplotypes A1, A2, B1, and B5. The phylogenetic tree separated haplotypes of both genes into two branches on the haplotype network indicating no distinct geographical clustering. This study is the first to highlight the prevalence of D. everestianus in Xizang, revealing moderate genetic differentiation among the four populations, possibly due to host mobility. This intensive investigation of genetic variation and population structure contributes valuable insights into the current population genetics of D. everestianus in Xizang, China.

BACKGROUND:Babesiosis is an emerging zoonosis worldwide that is caused by tick-borne apicomplexans, Babesia spp., which threatens the health of domesticated and wild mammals and even humans. Although it has done serious harm to animal husbandry and public health, the study of Babesia is still progressing slowly. Until now, no effective anti-Babesia vaccines have been available, and administration of combined drugs tends to produce side effects. Therefore, non-targeted metabolomics was employed in the present study to examine the temporal dynamic changes in the metabolic profile of the infected erythrocytes. The goal was to obtain new insight into pathogenesis of Babesia and to explore vaccine candidates or novel drug targets.METHODS:C57BL/6 mice were infected with B. microti and erythrocytes at different time points (0, 3, 6 , 9, 12, and 22-days post-infection) were subjected to parasitemia surveillance and then metabolomics analysis using liquid chromatography-mass spectrometry (LC-MS). Multivariate statistical analyses were performed to clearly separate and identify dysregulated metabolites in Babesia-infected mice. The analyses included principal components analysis (PCA) and orthogonal partial least squares-discrimination analysis (OPLS-DA). The time-series trends of the impacted molecules were analyzed using the R package Mfuzz and the fuzzy clustering principle. The temporal profiling of amino acids, lipids, and nucleotides in blood cells infected with B. microti were also investigated.RESULTS:B. microti infection resulted in a fast increase of parasitemia and serious alteration of the mouse metabolites. Through LC-MS metabolomics analysis, 10,289 substance peaks were detected and annotated to 3,705 components during the analysis period. There were 1,166 dysregulated metabolites, which were classified into 8 clusters according to the temporal trends. Consistent with the trend of parasitemia, the numbers of differential metabolites reached a peak of 525 at 6-days post-infection (dpi). Moreover, the central carbon metabolism in cancer demonstrated the most serious change during the infection process except for that observed at 6 dpi. Sabotage occurred in components involved in the TCA cycle, amino acids, lipids, and nucleotide metabolism.CONCLUSION:Our findings revealed a great alteration in the metabolites of Babesia-infected mice and shed new light on the pathogenesis of B. microti at the metabolic level. The results might lead to novel information about the mechanisms of pathopoiesis, babesisosis, and anti-parasite drug/vaccine development in the future.

为了解西藏部分地区牛体表寄生的硬蜱种类,试验分别从西藏林芝、拉萨地区采集硬蜱样本,首先用形态学方法对采集的硬蜱进行初步鉴定,然后根据硬蜱线粒体12S rDNA、16S rDNA、COXⅠ基因进行序列扩增并测序,再应用MEGA 7.0软件采用邻近法(Neighbor-joining method)构建系统进化树,进行分子进化分析,并与形态学结果相互验证.结果 表明:通过形态学初步鉴定西藏林芝地区所采集的样本为血蜱属成蜱,西藏拉萨地区所采集的样本为革蜱属成蜱.西藏林芝地区所采集的血蜱COX Ⅰ、12S rDNA、16S rDNA基因序列与GenBank中已知血蜱Haemaphysalis formosensis、Haemaphysa-lis longicornis、Haemaphysalis danieli核苷酸序列相似性分别仅为87.36％、91.28％、90.31％,而西藏拉萨地区所采集的革蜱COX Ⅰ、16S rDNA和12S rDNA基因序列与GenBank中已知革蜱Dermacentor everestianus核苷酸序列相似性分别为98.88％、98.76％和97.70％.根据不同基因所建系统进化树有所不同,但同一属内基因序列均能聚为一支.说明本次所采集的西藏拉萨蜱虫为西藏革蜱,西藏林芝所采集的蜱虫与GenBank中现有蜱虫核苷酸序列相似性较低,且进化树分析提示不同目标基因所建进化树结构不一致,因此其具体种属还需进一步研究.

Echinococcosis, also known as hydatid disease, is caused by the metacestode stage of the species cluster Echinococcus granulosus sensu lato (E. granulosus s.l.). It is almost widespread worldwide, especially in countries and regions dominated by animal husbandry. It is a major parasitic disease that seriously endangers human health, public health safety, environmental safety, and the development of animal husbandry production in western China. In this study, the mitochondrial cox1 gene was used to analyze the genetic diversity and haplotype of bovine and sheep echinococcal cysts isolated in Tibet. Echinococcus granulosus sensu stricto (E. granulosus s.s., G1, G3) was still the dominant species in the infected samples of yak and sheep in some parts of Tibet. Through haplotype analysis, Hap_1 was deemed the dominant haplotype, 14 of the 20 haplotypes were similar to the reference sequence previously published in Genbank, and the rest of the 6 haplotypes were found for the first time. Through Tajima's D value, neutral test Fu's Fs analysis, and haplotype network map, it can be concluded that Echinococcus population expansion has occurred in Xigaze, Tibet. This study provides basic data for understanding the genetic characteristics, epidemiology, and control of echinococcosis in this area.

东毕吸虫病是一种十分重要的人兽共患寄生虫病,严重威胁畜牧业发展和人体健康.本文通过总结分析西藏自治区东毕吸虫病的流行现状,提出防治对策,为开展东毕吸虫病防治、减少该病造成的损失、降低东毕吸虫病的危害供借鉴和参考依据.

住肉孢子虫病严重影响畜牧业健康发展,危害肉制品和公共卫生安全.为研究西藏拉萨市临近各县牛羊住肉孢子虫流行情况及虫种鉴定,对西藏拉萨市当雄县和尼木县的牦牛、绵羊、山羊、黄牛、犏牛等共62头(只)牛羊的心肌、膈肌、腿肌、食道肌进行采样.采用压片镜检法对采集的牛羊膈肌进行观察检测,若发现住肉孢子虫包囊即判定为阳性,否则为阴性.采用PCR技术对住肉孢子虫线粒体细胞色素C氧化酶第一亚基(COX1)进行扩增,对62头(只)牛羊的心肌、膈肌、腿肌、食道肌进行检测.结果显示,PCR检测的住肉孢子虫病的阳性率与压片镜检法结果一致,藏牛羊的住肉孢子虫阳性率70.97％;对膈肌PCR产物进行克隆测序,在NCBI上进行同源性比对,共检出4个住肉孢子虫虫种,分别为肉孢子虫(Sarcocystis pilosa)、山羊犬住肉孢子虫(Sarcocystis capracanis)、羊柔嫩住肉孢子虫(Sarcocystis tenella)和家山羊犬肉孢子虫(Sarcocystis hircicanis),对应样品编号分别为5C、17C、19C和27C,其同源性分别为92.10％、99.71％、99.81％和99.26％;种系发育树结果显示,样品5C、17C、19C、27C与其NCBI上同源性最高的住肉孢子虫虫种Sarcocystis pilosa、Sarcocystis capracani、Sarcocystis tenella和Sarcocystis hircicanis处于同一分支上,且系统发育树中的Bootstrap值较高,很好地证明了研究结果中所确定的分类地位,两者确定为同一种属.另外,在牦牛身上检出了Sarcocystis pilosa,为进一步了解Sarcocystis pilosa生活史提供了线索.

Although the prevalence of schistosomiasis japonica has declined gradually in China, more accurate and sensitive diagnostic methods are urgently needed for the prevention and control of this disease. Molecular diagnostic methods are advantageous in terms of sensitivity and specificity, but they are time-consuming and require expensive instruments and skilled personnel, which limits their application in low-resource settings. In this study, an isothermal DNA amplification assay and recombinase polymerase amplification (RPA) combined with lateral flow dipstick (LFD) were set up. It was used to detect S. japonicum infections in experimental mice and domestic goats by amplifying a specific DNA fragment of S. japonicum. The lower limit of detection for the LFD-RPA assay was evaluated using dilutions of plasmid containing the target sequence. Cross-reactivity was evaluated using genomic DNA from eight other parasites. The effectiveness of the LFD-RPA assay was verified by assessing 36 positive plasma samples and 36 negative plasma samples from mice. The LFD-RPA assay and real-time PCR were also used to assess 48 schistosomiasis japonica-positive plasma samples and 53 negative plasma samples from goats. The LFD-RPA assay could detect 2.6 femtogram (fg) of S. japonicum target DNA (~39 fg genomic DNA of S. japonicum), only 10-fold less sensitive than real-time PCR assay. There was no cross-reactivity with DNA from the other eight parasites, such as Haemonchus contortus and Spirometra. The whole amplification process could be completed within 15 min at 39°C, and the results can be observed easily using the LFD. The sensitivity and specificity of the LFD-RPA assay were 97.22% (35/36, 95% CI, 85.47%–99.93%) and 100% (36/36, 95% CI, 90.26%–100%) in mice, and 93.75% (45/48, 95% CI, 82.80%–98.69%) and 100% (53/53, 95% CI, 93.28%–100%) in goats. By comparison, the sensitivity and specificity of real-time PCR were 100% (36/36, 95% CI, 90.26%–100%) and 100% (36/36, 95% CI, 90.26%–100%) for mice, and 97.92% (47/48, 95% CI, 88.93%–99.95%) and 100% (53/53, 95% CI, 93.28%–100%) for goats. The LFD-RPA assay exhibits high sensitivity and specificity for the diagnosis of schistosomiasis japonica, and it is an alternative method for diagnosis schistosomiasis japonica in low resource setting.

藏猪是西藏特有的地方猪种,具有十分重要的生态价值、经济价值和科研价值,非洲猪瘟是猪的一种急性烈性传染病,我区发生非洲猪瘟疫情后,部分地区的纯种藏猪被扑杀殆尽,藏猪产业发展受到巨大打击,脱贫攻坚工作遭受极大挫折,为更好保护藏猪遗传资源,发展藏猪健康养殖,使其更好为国民经济社会服务,本文从藏猪非洲猪瘟的防控入手,以期促进藏猪养殖中非洲猪瘟疫情防控工作.

[目的]分析牛脾气蝇蛆病防治效率影响因素.[方法]利用TRIZ理论中的矛盾矩阵原理进行防治方法分析.[结果]应用TRIZ方法对牦牛皮蝇蛆病问题进行了系统分析,结合创新理论提出皮蝇蛆病防治方案8个,并对这几种方法进行了分析和比较,提出了4种目前较为可行的方法.[结论]TRIZ创新工具为牦牛皮蝇蛆病防控提供技术思路创新,拓展了防治思路.

本研究旨在对西藏自治区那曲地区和拉萨市牦牛、绵羊体内棘球蚴病原进行分子生物学鉴定并分析其遗传变异规律.对2016年11月底采自西藏拉萨市当雄县和那曲地区嘉黎县的5只绵羊体内的5个棘球蚴包囊、15头牦牛体内的18个棘球蚴包囊分别分离棘球蚴原头蚴或生发层组织,提取基因组DNA,应用PCR方法扩增nad1基因,通过测序获得nad全基因序列.运用DNAStar MegAlign软件对序列进行同源性分析.以GenBank中已公布的棘球属的nad1全基因序列为比对对象,采用最大似然法(ML)构建系统发育树.结果 显示,所测定的牦牛和绵羊的23个棘球蚴病原nad1基因序列与GenBank登录的细粒棘球蚴狭义种(G1基因型)nad1基因序列高度同源,同源性为99.6～99.8％,23条naa1基因的遗传距离为0～0.0022447.同源基因的碱基变异率为0.2％～0.4％;与棘球属其他棘球绦虫同源基因的碱基变异率为14.9％～19.8％.有5个样本的nad1基因在不同位点发生碱基突变,变异位点发生序列转换.以上结果表明,本研究所采集牦牛和绵羊的棘球蚴为细粒棘球绦虫G1基因型,其nad1基因变异小,序列一致性高.

伊维菌素是一种高效、广谱、安全的抗寄生虫药物,其长效制剂的研发已成为当今兽药领域的热门课题.文章介绍了伊维菌素缓释巨丸剂、控释胶囊、长效注射剂、微球、微囊、纳米粒制剂及皮下埋植剂等多种长效制剂的研究进展,分析并针对该类制剂在研究及应用中存在的生产工艺复杂、成本高、制剂类型相对单一、耐药性、药物组成单一等问题,提出多种药物合理配伍、研制复方伊维菌素长效制剂等建议.

Background The existing diagnostic techniques for detecting schistosomiasis turkestanica, such as aetiological assays, identify infection by parasitic worms via the incubation of miracidia from faeces or observing eggs under microscopy. However, they are limited in the diagnosis of low-grade and prepatent infections, which lead to a high misdetection rates. Therefore, a new method for parasite diagnosis with increased sensitivity is urgently needed. Methods Goats in Nimu County (Tibet, China) infected with Schistosoma turkestanicum in an epidemic area were selected according positivity for the infection by faecal examination. Adult worms were collected, eggs were extracted by the sodium hydroxide (NaOH) erosion method, and soluble worm antigen preparation (SWAP) and soluble egg antigen (SEA) were isolated. The best coating concentration of the antigens and the best degree of dilution for serum were determined by square array experiments, and the optimal blocking solution and serum diluents were selected. The specificity, sensitivity and crossover of the ELISA method were determined using 48 samples of goat sera positive for S. turkestanicum, 100 samples of goat sera negative for S. turkestanicum, and 54 samples of buffalo sera positive for S. japonicum. Serological assays were established with samples from goats naturally grazed in a rural area of Nimu County, Tibet Province, by using the indirect ELISA method for the diagnosis of schistosomiasis, and faeces were collected for miracidia hatching. The sensitivity of the two detection methods was compared. Results Eggs of S. turkestanicum were distributed in the host duodenum and small intestine. Eggs in the host intestinal wall were extracted by the NaOH erosion method, which provided intact eggs with reduced impurities. The testing results obtained by isolating SEA were more stable than those obtained by using SWAP and less affected by the coating concentration and serum dilution. Additionally, the value of positive serum/negative (P/N) serum for SEA was much higher than that for SWAP. The optimal coating concentration of SEA was 0.5 μg/ml, and the optimal serum dilution was 1:100. The specificity and sensitivity of the indirect ELISA based on SEA (S. turkestanicum) were both 100%, and no cross-reactivity was found with schistosomiasis japonica. An epidemiological survey of goats in naturally infected areas showed that the prevalence rate of schistosomiasis turkestanica was 93%, and the infection rate increased with the ages of the goats. Conclusion We aimed to develop a sensitive method to utilize in the mass field screening of livestock. As a diagnostic antigen, SEA (S. turkestanicum) was more suitable for serological testing than SWAP (S. turkestanicum). The indirect ELISA using SEA (S. turkestanicum) exhibited good sensitivity, specificity and no cross-reactivity with schistosomiasis japonica. The degree of infectivity and prevalence of S. turkestanicum infection in endemic areas are serious and should be a focus of concern among local departments.

为了解致西藏日喀则市某村死亡绵羊感染的主要病原,试验对采集的绵羊肝脏、肺脏、脾脏等病料组织进行病原菌的分离培养,对分离纯化后的细菌进行革兰氏染色;根据染色结果选择细菌鉴定卡和药敏鉴定卡进行鉴定,并对分离菌进行致病性分析;通过16S rRNA引物对分离菌进行PCR鉴定和遗传进化分析.结果 表明:分离菌为革兰氏阴性;对分离的1株优势菌进行全自动微生物鉴定系统VITEK2 Compact System的GN卡鉴定,结果为鲍曼不动杆菌复合物;分离菌对氨苄西林/舒巴坦、亚胺培南、庆大霉素、复方新诺明等8种药物敏感,对氨苄西林、头孢呋辛酯、安曲南、呋喃妥因等7种药物不敏感,对头孢曲松中度敏感;动物致病性试验结果表明,本菌具有一定的毒力;PCR产物测序比对后鉴定该菌为醋酸钙不动杆菌;遗传进化分析结果显示,该菌与序列号为MG011594.1的醋酸钙不动杆菌相似性达100％,确定为醋酸钙不动杆菌.说明西藏日喀则市某村死亡绵羊感染了醋酸钙不动杆菌,应加强防控.

通过对生长初期疯草内生真菌U.oxytropis菌丝复苏后连续培养32 d,每隔4d取样1次,并设3个平行培养组,测定其不同培养时期菌丝干重变化,利用超声减压旋蒸法提取菌丝和发酵液中苦马豆素(SW),并分别利用薄层层析法、气相色谱法和α-甘露糖苷酶抑制法对菌丝、发酵液中SW含量进行测定.结果 显示,经测定疯草内生真菌U.oxytropis菌丝干重质量,确定疯草内生真菌U.oxytropis生长周期为24 d;薄层层析法、气相色谱法和α-甘露糖苷酶抑制法都可快速对菌丝和发酵液中提取的SW进行定性、定量检测,并比较3种检测方法,发现气相色谱法检测限低、灵敏度更高.本试验完成了疯草内生真菌U.oxytropis生长周期的测定,并建立了菌丝、发酵液中SW的有效、快速提取及检测方法,为下一步产苦马豆素疯草内生真菌U.oxytropis生物合成机理的研究奠定基础.

Background Cystic echinococcosis (CE) in humans and livestock is caused by Echinococcus granulosus ( sensu lato ). In China where CE is endemic, a number of studies have shown that Echinococcus granulosus ( sensu stricto ) is majorly responsible for CE. However, E. canadensis (G6) which is the second leading cause of CE is now being detected in most parts of the country. In this study, the species diversity and genetic variation of Echinococcus granulosus ( s.l. ) in four counties in Tibet Autonomous Region of China were investigated. Methods Infection with Echinococcus granulosus ( s.s. ) in yaks and sheep was identified using NADH dehydrogenase subunit 1 and 5 ( nad 1 and nad 5) mitochondrial genes while the genotype G6 of E. canadensis initially diagnosed with NADH dehydrogenase subunit 1 ( nad 1) was further confirmed by analysis of the complete mitochondrial genome and a phylogenetic network constructed based on the nad 2 and nad 5 genes. Results Out of 85 hydatid cyst samples collected from slaughtered sheep ( n = 54) and yaks ( n = 31), 83 were identified as E. granulosus ( s.s. ) G1 ( n = 77), G3 ( n = 6) and 2 were identified as E. canadensis G6. Analysis of the nad 1/ nad 5 genes revealed 16/17 mutations with 9/14 parsimony informative sites resulting in 15/14 haplotypes, respectively. Haplotype diversity (Hd) and nucleotide diversity (π) of E. granulosus ( s.s. ) population were 0.650 and 0.00127 for nad 1 and 0.782 and 0.00306 for nad 5, respectively, with an overall negative Tajima’s D and Fu’s Fs. A low F ST indicated no genetic difference between isolates from sheep and yaks. Conclusion Pockets of infection with E. canadensis (G6, G7, G8 and G10) have been previously reported in sheep, goats, yaks and/or humans in different parts of China. While the G6 genotype has been previously reported in sheep in the Tibet Autonomous Region, the detection in a yak in the present study represents the first to the best of our knowledge. Therefore, we recommend future surveys and control efforts to comprehensively investigate other potential intermediate hosts for the prevalence and genetic diversity of the E. canadensis group (G6, G7, G8 and G10) across the country and their inclusion into the existing CE control programme.

Enterocytozoon bieneusi and Giardia duodenalis are important opportunistic enteric zoonotic pathogens that cause diarrhoea and intestinal diseases in animals and humans. China is the largest producer of pigs, but whether Tibetan pigs, a unique pig breed in Tibet, are infected with E. bieneusi and G. duodenalis is unknown. Therefore, we conducted a molecular epidemiological survey to determine the prevalence of E. bieneusi and G. duodenalis in Tibetan pigs in Tibet, China, and identified the genotypes of these causative agents. A total of 345 faecal specimens were collected from Tibetan pigs from three Tibet counties (Milin, Cuona and Gongbujiangda), examined by nested PCR and sequenced utilizing genetic markers in the ribosomal internal transcribed spacer (ITS) region of the rRNA and glutamate dehydrogenase (gdh) gene for E. bieneusi and G. duodenalis, respectively. Moreover, using multilocus sequence typing, the subtypes of E. bieneusi were identified based on four loci (MS1, MS3, MS4 and MS7). A total of 41 (11.88%) faecal samples from Tibetan pigs were E. bieneusi-positive, and 2 (0.58%) were G. duodenalis-positive. The multivariate logistic regression analysis showed that age was considered a risk factor for Tibetan pig infection of E. bieneusi. Two novel (GB11, GB31) and four known E. bieneusi genotypes (EbpC, EbpD, PigEBITS5 and CHS12) were identified and were all classified as zoonotic group 1 according to the phylogenetic analysis. Two MLGs (MLGI and MLGII) were further identified in the E. bieneusi EbpC genotype by multilocus sequence typing analysis. In addition, two G. duodenalis assemblages (D and E) were found in the present study. To our knowledge, the current study is the first to detect the prevalence and perform genetic characterization of G. duodenalis in Tibetan pigs in Tibet, China. The results could provide essential data for controlling E. bieneusi and G. duodenalis infections in Tibetan pigs that are in contact with other animals and humans, as Tibetan pigs could be a potential source for human infection by these pathogens.

目的 牦牛牛皮蝇蛆病在西藏对牦牛养殖业危害严重,主要目的分析西藏牦牛牛皮蝇蛆病流行现状并提出综合防治措施.方法 文章采用调研与资料查阅相结合方法,对中国五大牧区牛皮蝇蛆病流行现状、危害以及国内外的主要做法进行分析总结,并根据西藏实际提出相应防治措施.结果 西藏牦牛牛皮蝇蛆病感染率高、感染强度大,调查显示西藏没有专门针对牛皮蝇蛆病开展的防治工作,该病危害十分严重,无形中对西藏牦牛养殖业造成巨大的经济损失.结论 建议西藏设立重要寄生虫病防控管理机构,开展牦牛牛皮蝇蛆病防治工作,采取"春防、秋治"的综合措施,长期坚持必将收到良好的效果.