Using genetic markers defined previously in the second internal transcribed spacer (ITS-2) of nuclear ribosomal DNA (rDNA), isotopic, and non-isotopic polymerase-chain-reaction-coupled single-strand conformation polymorphism (SSCP) were utilized to identify each of three anisakid species [Anisakis simplex (s.l.), Contracaecum osculatum (s.l.), and Hysterothylacium aduncum] from different host species and geographical locations in Poland and Sweden. While subtle microheterogeneity was observed within each of Anisakis simplex (s.l.) and H. aduncum, distinct SSCP profiles were displayed for each of the three species, allowing identification and differentiation of the three taxa. Subsequent sequencing of the ITS-1 and ITS-2 rDNA revealed that A. simplex (s.l.) represented Anisakis simplex s.s. and Contracaecum osculatum (s.l.) represented C. osculatum C. Application of the non-isotopic SSCP assay of ITS-2 to larval anisakid samples from different hosts and geographical locations in China revealed three distinct SSCP profiles, one of which was consistent with that of A. simplex (s.l.), and the other two had different SSCP profiles from that of C. osculatum C and H. aduncum. Sequencing of the ITS-1 and ITS-2 rDNA for representative Chinese anisakid samples examined revealed three anisakid species in China, i.e., Anisakis typica, Anisakis pegreffii, and Hysterothylacium sp. These molecular tools will be useful for identification and investigation of the ecology of anisakid nematodes in China and elsewhere.

Real-time RT-PCR assay, based on light upon extension (LUX) fluorogenic primer and LightCycle technology, was developed for rapid detection of transmissible gastroenteritis virus (TGEV). Viral RNA from different TGEV isolates and clinical specimens was detected. To evaluate the sensitivity of the assay, a gel-based RT-PCR method targeted at the same 101 bp sequence was also developed. Serial 10-fold dilutions of TGEV RNA were detected by the two methods. Although the real time method used only 2 microl RNA for each reaction, a 10-fold increase of sensitivity over that of the gel-based method, which used 10 microl RNA was demonstrated. The study indicates that the LUX assay reported below is rapid, reliable and sensitive and it has the potential for use as an alternative molecular method for TGEV diagnosis.

In this study, we obtained the whole genomes of three porcine bocaparvovirus (PBoV) strains (GD6, GD10, and GD23) by polymerase chain reaction. Sequence analysis showed that all three field strains belonged to PBoV group 3 (G3). The phylogenetic trees based on NS1, NP1, and VP1 differed to the extent that these PBoVs were potentially more closely related to bocaparvoviruses known to infect other animals than to other PBoVs. GD6, GD10, and GD23 all included the conserved sequences YLGPF and HDXXY, with known phospholipase A2 activity. Using recombination-detection software we identified a natural recombinant breakpoint in the NS1 region of PBoV G3. The results of this study will further the epidemiological characterization of PBoVs.