Quarantine And Risk Assessment Of Terrapin Eggs Imported From Taiwan

Terrapin is a kind of aquatic products with very high nutritional value and medicinal value.In mainland China, terrapin eggs for hatching seedlings were mainly imported from Taiwan. Atthe present stage, it is reported that only few surveys about pathogenic bacteria were carried outby terrapin eggs in China. Sometimes, vibrio cholerae was detected in imported terrapin eggs,and food poisoning also occurred due to eating terrapin eggs in Taiwan. Therefore, pathogenicbacteria carried by terrapin eggs imported from Taiwan were detected by Matrix assisted laserdesorption/ionization time of flight mass spectrometry (MALDI-TOF-MS), VITEK2Compactautomatic biochemical analyzer, Serological methods and PCR in this study. The proteinfingerprint database was developed for main pathogenic bacteria isolated from terrapin eggsimported from Taiwan. In addition, nano-gold PCR methods were established to detect E. Coli,Salmonella, Vibrio cholerae and Citrobacter freundii. According to the risk analysismanagements and regulations about imported animals and animal products issued by AQSIQ,soft shelled terrapin eggs imported from Taiwan were assessed in qualitative risk. The results ofthis experiment were as follows:1.257strains of pathogenic bacteria(including25genera and51species) were isolated from73batches of terrapin eggs imported from Taiwan and indentified by MALDI-TOF-MS.90.41%of terrapin eggs imported from Taiwan were contaminated with pathogenic bacteria. Most of theterrapin eggs carried two or more pathogenic bacteria. MALDI-TOF-MS protein fingerprintdatabase contains162strains of pathogenic bacteria from32isolated bacteria species.2. The nano-gold PCR methods were established to detect E. Coli, Salmonella, vibriocholerae and Citrobacter freundii. The methods have good specificity and sensitivity byoptimizing the annealing temperature and primer concentrations.3. Pathogenic analysis was made in bacterial disease carrying by terrapin eggs importedfrom Taiwan. Qualitative risk assessments were developed from7strong pathogenic bacteria(Aeromonas hydrophila, Edwardsiella tarda, Vibrio cholera, Salmonella, Escherichia coli O157,Klebsiella pneumoniae and Vibrio parahaemolyticus). The results showed that Vibrio cholera ishigher risk bacterial disease, and5kinds of other bacterial diseases have medium risk except thatEscherichia coli O157is low risk. The corresponding measures of risk management wereproposed on the basis of risk assessment.In short, this study has investigated the pathogens carried by terrapin eggs imported from Taiwan with MALDI-TOF-MS. At present, it has developed a protein fingerprint database fordetecting major pathogens isolated from terrapin eggs imported from Taiwan. The nano-goldPCR methods have been applied to detect E. Coli, Salmonella, vibrio cholerae and Citrobacterfreundii. A qualitative risk assessment also has been made for terrapin eggs imported fromTaiwan. It is very important that above results can help reduce the risk of foodborne illnesscarried by animals and animal products imported from Taiwan and strengthen cross-strait tradeof terrapin eggs.