Molecular and phylogenetic analysis of Anaplasma spp. in sheep and goats from six provinces of China

Members of the genus Anaplasma are important emerging tick-borne pathogens in both humans and animals in tropical and subtropical areas. Here, we investigated the presence of Anaplasma spp. in 621 sheep and 710 goats from six provinces of China. Polymerase chain reaction (PCR) and DNA sequencing were conducted to determine the prevalence of Anaplasma (A.) phagocytophilum, A. ovis and A. bovis targeting the 16S ribosomal RNA or the major surface protein 4 gene. PCR revealed Anaplasma in 39.0% (240/621) of sheep and 45.5% (323/710) of goats. The most frequently detected species was A. ovis (88/621, 14.2% for sheep; 129/710, 18.2% for goats), followed by A. bovis (60/621, 9.7% for sheep; 74/710, 10.4% for goats) and A. phagocytophilum (33/621, 5.3% for sheep; 15/710, 2.1% for goats). Additionally, eight sheep and 20 goats were found to be infected with three pathogens simultaneously. DNA sequencing confirmed the presence of these three Anaplasma species in the investigated areas, and phylogenetic analysis indicated that there was geographic segregation to a certain extent, as well as a relationship between the host and cluster of A. ovis. The results of the present study provide valuable data that helps understand the epidemiology of anaplasmosis in ruminants from China.

Isolation and identification of Escherichia coli O157∶H7 from cow and its biological characteristics / 中国人兽共患病学报

To understand the Escherichia coli (E .coli) O157∶ H7 isolated from cow in Zhengzhou ,Henan Province ,a total of 146 samples of cow fecal and milk were collected in the different farms ,and E .coli O157∶ H7 was detected with mul-tiplex polymerase chain reaction (PCR) in our laboratory .Then the biochemical characteristics ,growth dynamic ,the biofilm formation ,and the toxin genes of the E .coli O157∶ H7 isolates were analyzed .The results showed that 2 strains of E .coli O157∶H7 were found ,with the detection rate of 1 .4% ,and the isolates were named as L1 and L2 in current study ,respec-tively .The E .coli O157∶H7 clinical isolates had the same biochemical characteristics with that of the typical E .coli .The L1 and L2 isolates presented similar growth curve ,which entered into the log phase earlier than that of the standard strain .L1 strain formed thick ,confluent ,complete biofilm after 48 hours post-inoculation ,and the biofilm of L2 strain was formed com-pletely in 36 hours .The two E .coli O157∶ H7 isolates were positive with eaeA and hlyA genes ,and the L1 strain also carried the Stx2 virulence gene .Our results reinforce the epidemiological data of E .coli O157∶H7 ,and underscore the need for more effective surveillance of animal-derived E .coli O157∶H7 isolates in Zhengzhou City ,China .

Research progress of molecular examination and genotyping method for Entamoeba / 中国人兽共患病学报

Entamoeba is a zoonotic protozoan that can parasitize in the intestine and other organs in human and animals . There are many species in this genus ,but only Entamoeba histolytica can cause amebic colitis and liver abscess ,and even death .The cysts and trophozoits are difficult to be discriminated for pathogenic and nonpathogenic Entamoeba .And there is al-so difference in the pathogenicity ,infectivity etc .,even in the same species .Therefore ,it is difficult to confirm the Entamoeba species according to traditional method ,thus affecting the use of medicine .In this article ,the research progress of molecular examination and genotyping method about entamoeba are reviewed .

Study on the in vitro excystation of Cryptosporidium oocysts under different conditions / 中国人兽共患病学报

The aim of the present study was to evaluate the effect of storage conditions,pretreatment,temperature,time and excystation solutions on in vitro excystation of Cryptosporidium oocyst.Cryptosporidium andersoni oocyst was used as a model and the results showed that 0.5% sodium hypochlorite could enhance the excystation rates.But there was no significant difference compared with oocysts untreated by sodium hypochlorite(P＞0.05).0.75% synthetic sodium taurocholate and 1% bile solution could urge the excystation of oocysts,which were significantly different compared with the excystation rate of oocysts in 0.25% trypsin solution or in PBS(P<0.05).The excystation rates of oocysts in acidic water (pH =3) were similar with the rates in PBS (pH =7.2) but significantly different from the rates in alkaline water (pH =9) (P<0.01).Additionally,the excystation rate of oocysts in water of 24℃ was significantly lower than in water of 37℃(P<0.01),and the excystation rate of oocysts raised gradually at 37℃ with the passage of time.It's concluded that temperature,acidity and excystation solution were vital factors for the in vitro excystation of Cryptosporidium oocyst.A higher excystation rate could be observed when oocysts were pretreated with 0.5% sodium hypochlorite and treated with 0.75% synthetic sodium taurocholate at 37℃ for 3 hours.