Objective:The overexploitation of the sea urchin Paracentrotus lividus stock,as a consequence of the growing market demand for roe,has boosted the research for echinoderm rearing.The chemical,physical,and microbiologi...Objective:The overexploitation of the sea urchin Paracentrotus lividus stock,as a consequence of the growing market demand for roe,has boosted the research for echinoderm rearing.The chemical,physical,and microbiological characteristics of land-based facilities are crucial for sea urchins’health and human consumption of their products.In Italy,health-hygienic regulations for P.lividus rearing are still to be perfected by the authorities.In this context,we characterized the microbiological quality of a pilot land-based facility for sea urchin production at the University of Cagliari(Italy)to support the development of technical production regulations.Materials and Methods:The accredited Hygiene Laboratory of Cagliari University collected and analyzed the samples in June 2023.Mesophilic bacteria,yeasts,and molds were searched for in air and on surfaces.Total coliforms and Escherichia coli,Enterococci,Pseudomonadaceae,Staphylococcus aureus,sulfite-reducing Clostridia,and Vibrio spp.were identified in water samples.We searched forVibrio spp.and Pseudomonas spp.in the gonads and coelomic fluid of sea urchins.Results:Although air,surfaces,and water quality were satisfactory overall,some critical points should be monitored more strictly.Enterococci concentration was 250 CFU/100 mL in the water reserve,suggesting animal contamination(other than humans).Pseudomonas aeruginosa was the most resistant to filtration processes,with a residual concentration of 6 CFU/250 mL after the second filtration.No colonies of Vibrio spp.or Pseudomonas spp.were isolated in sea urchins’gonads or coelomic fluid.Conclusions:Starting from the results,we provided targeted advice for developing technical production regulations,system monitoring,and facility routine maintenance in accordance with the‘best practice’approach.This analysis could be considered a first step toward the elaboration of common regulations about the minimal standards for the breeding environment of P.lividus by national and regional authorities.展开更多
Mussels close their shell as a protective strategy and the quantification of this behavioral marker may represent an alarm signal when they are exposed to environmental stressors.In the present study,we investigated t...Mussels close their shell as a protective strategy and the quantification of this behavioral marker may represent an alarm signal when they are exposed to environmental stressors.In the present study,we investigated the ability of the Mediterranean mussel Mytilus galloprovincialis to recover and then the resilience or inertia of valve activity after a pulsing exposition to diverse levels of salinity(5,10,20,and 35 PSU as reference value).The trial simulated an event of drastic and sudden reduction of seawater salinity thus mimicking an event of flash flood from intense rain.Valve gaping and movements were measured in continuous cycle for 10 days using a customized magnetoelectric device which uses Hall sensors.Results showed that under normal conditions of salinity(35 PSU),the general pattern of valve movements was a continuously open state with sporadic spikes indicating a closing motion.At salinity of 5,PSU mussels reacted by closing their valves,leading to a 77%mortality on the 4th day.At salinity of 10,PSU animals were observed with closed valves for the entire duration of the exposure and no mortality occurred,they showed a significant reduction in the valve activity once the reference value of salinity was reestablished.In contrast,salinity of 20 PSU did not trigger a significant behavioral response.Interestingly,there no define rhythms of valve movements were recorded during salinity challenges.展开更多
基金funded by National Recovery and Resilience Plan(NRRP),mission 4 Component 2 Investment 1.5,Project name:eINS Ecosystem of Innovation for Next Generation Sardinia(No.ECS0000038-CUP F53C22000430001),Italy.
文摘Objective:The overexploitation of the sea urchin Paracentrotus lividus stock,as a consequence of the growing market demand for roe,has boosted the research for echinoderm rearing.The chemical,physical,and microbiological characteristics of land-based facilities are crucial for sea urchins’health and human consumption of their products.In Italy,health-hygienic regulations for P.lividus rearing are still to be perfected by the authorities.In this context,we characterized the microbiological quality of a pilot land-based facility for sea urchin production at the University of Cagliari(Italy)to support the development of technical production regulations.Materials and Methods:The accredited Hygiene Laboratory of Cagliari University collected and analyzed the samples in June 2023.Mesophilic bacteria,yeasts,and molds were searched for in air and on surfaces.Total coliforms and Escherichia coli,Enterococci,Pseudomonadaceae,Staphylococcus aureus,sulfite-reducing Clostridia,and Vibrio spp.were identified in water samples.We searched forVibrio spp.and Pseudomonas spp.in the gonads and coelomic fluid of sea urchins.Results:Although air,surfaces,and water quality were satisfactory overall,some critical points should be monitored more strictly.Enterococci concentration was 250 CFU/100 mL in the water reserve,suggesting animal contamination(other than humans).Pseudomonas aeruginosa was the most resistant to filtration processes,with a residual concentration of 6 CFU/250 mL after the second filtration.No colonies of Vibrio spp.or Pseudomonas spp.were isolated in sea urchins’gonads or coelomic fluid.Conclusions:Starting from the results,we provided targeted advice for developing technical production regulations,system monitoring,and facility routine maintenance in accordance with the‘best practice’approach.This analysis could be considered a first step toward the elaboration of common regulations about the minimal standards for the breeding environment of P.lividus by national and regional authorities.
基金This study is part of the project“Effects of climate environmental shifts on species,communities and ecosystems,”funded by the Fondazione di Sardegna(2018).
文摘Mussels close their shell as a protective strategy and the quantification of this behavioral marker may represent an alarm signal when they are exposed to environmental stressors.In the present study,we investigated the ability of the Mediterranean mussel Mytilus galloprovincialis to recover and then the resilience or inertia of valve activity after a pulsing exposition to diverse levels of salinity(5,10,20,and 35 PSU as reference value).The trial simulated an event of drastic and sudden reduction of seawater salinity thus mimicking an event of flash flood from intense rain.Valve gaping and movements were measured in continuous cycle for 10 days using a customized magnetoelectric device which uses Hall sensors.Results showed that under normal conditions of salinity(35 PSU),the general pattern of valve movements was a continuously open state with sporadic spikes indicating a closing motion.At salinity of 5,PSU mussels reacted by closing their valves,leading to a 77%mortality on the 4th day.At salinity of 10,PSU animals were observed with closed valves for the entire duration of the exposure and no mortality occurred,they showed a significant reduction in the valve activity once the reference value of salinity was reestablished.In contrast,salinity of 20 PSU did not trigger a significant behavioral response.Interestingly,there no define rhythms of valve movements were recorded during salinity challenges.
