[Hereditary quality standards for laboratory fish].

Although laboratory fish are increasingly used in genetics and other life science research fields, standard quality control and supervision are needed. In China, laboratory animals are all put into a strict licensing and quality management system by the government. The standardization of genetic quality control is crucial to a laboratory fish quality control management system. The goal of Laboratory Animal Regulation is to control genetic quality, avoid hereditary degeneration and genetic drift, and circumvent experimental errors. To achieve this goal, Laboratory Animal Regulations are being developed by consulting experimental data and research findings throughout the world, combining the best known practices in laboratory fish production, and consulting specialists. A new set of laboratory fish genetic quality standards focusing on zebrafish and swordtail fish has been established as a reference for scientific researchers. The new standards define inbred and outbred zebrafish and swordtail fish hereditary classifications, naming principles, breeding methods, and hereditary quality surveying. The new standards provide a frame of reference for laboratory fish users and managers.

[Development and application of TaqMan MGB probe fluorescence quantitative PCR method for rapid detection of Clostridium piliforme].

OBJECTIVE: To develop a TaqMan MGB probe-based, sensitive and specific fluorescence quantitative PCR assay method for rapid detection of Clostridium piliforme. METHODS: Primers and probes specific to 16S rRNA gene of Clostridium piliforme were designed. A TaqMan MGB probe-based, fluorescence quantitative PCR method was established. Specificity, sensitivity and stability of the method were assessed, followed by real-time quantitative PCR assay to detect Clostridium piliforme on 1156 clinical specimens during 2008-2011 and compared with conventional PCR assay. RESULTS: The specificity of TaqMan MGB probe-based fluorescence quantitative PCR was high and did not show cross-reactivity with Helicobacter hepaticus, Helicobacter pylori, Campylobacter jejuni, Pasteurella pneumotropica, Escherichia coli or Pseudomonas aeruginosa. The detection limit was 2.2 copies/µl. The correlation coefficient and slope value of standard curve were 0.999 and -3.204, respectively and the efficiency of TaqMan MGB-based probe fluorescence quantitative PCR assay was 100%. When the TaqMan MGB-based probe fluorescence quantitative PCR assay was preformed to detect Clostridium piliforme on 1156 clinical specimens, a total of 101 specimens showed positive on Clostridium piliforme. However, only 44 specimens showed positive when conventional PCR was used. The real-time quantitative PCR for Clostridium piliforme could be completed within 2 hours. CONCLUSION: The TaqMan MGB-based probe fluorescence quantitative PCR assay method was a reliable, specific, sensitive and useful tool for rapid detection of Clostridium piliforme.

[Microsatellite analysis in Wistar and Spague-Darley outbred rats].

Genetic quality of outbred stock has an important effect for the experimental results by using those animals, but methods and standardization of genetic detection for outbred stock are absent. In the present study, 6 microsatellite markers were screened for Wistar from Beijing and Spague-Darley (SD) from Shanghai outbred rats by fluorescence-based semi-automated genotyping method. Good polymorphisms were detected on all the 6 microsatellite loci, with 36 alleles found in the 2 stocks, 5-8 alleles each locus, and the polymorphic information content (PIC) ranged from 0.5892 (D11Mgh3) to 0.8019 (D6Mit1), with an average of 0.6881. 25 and 26 alleles were detected in the 6 loci, and averages of unbiased expected heterozygosity were 0.6260 and 0.6249 in Wistar and SD outbred rats, respectively. No significant differences of genetic diversity index were tested between populations. The Fst per locus was varied from 0.0461 to 0.4363, and the average Fst of all loci was 0.2069, which implied large genetic differentiation between populations. Nei's (1972) genetic distance and Nei's (1978) unbiased genetic distance measures between the 2 stocks were 1.2862 and 1.2726, respectively, which indicated the distant genetic relationship and low genetic identity between them. All loci in Wistar and 4 of 6 loci in SD outbred rats showed significant deviations from Hardy-Weinberg equilibrium (HWE), and all deviations were caused by deficiency of heterozygous individuals. From the results, there is abundant genetic variation in Wistar and SD outbred rats. Large genetic differentiation existed between these two outbred stocks, and each possessed distinct genetic characteristic. Deviation from HWE seems a frequent problem in the 2 outbred stocks. This genetic research on outbred rats should assist in developing genetic monitoring methods and standardization of the outbred rats.