Identification and characterization of atypical porcine pestivirus genomes in newborn piglets with congenital tremor in China

Recently, a novel atypical porcine pestivirus (APPV) in pig was reported. In this study, two APPV strains, APPV-China/GZ01/2016 (GZ01) and APPV-China/GD-SD/2016 (GD-SD), were identified in two newborn piglet herds with congenital tremor from China. The open reading frame of the two strains shared an 83.5% nucleotide identity. Phylogenetically, the APPV strains were placed into two groups: GZ01 belonged to group I and GD-SD belonged to group II. A high viral load was detected in the cerebellum (quantification cycles < 26). Further studies should be carried out to thoroughly elucidate the development of congenital tremors caused by APPV.

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.