Multiple non-species-specific pathogens possibly triggered the mass mortality in Pinna nobilis

The fan mussel, Pinna nobilis, represents the largest bivalve endemic to the Mediterranean Sea. Since 2016, dramatic mass mortality of this species has been observed in several areas. The first surveys suggested that Haplosporidium pinnae (currently considered species-specific) was the main etiological agent, but recent studies have indicated that a multifactorial disease may be responsible for this phenomenon. In this study, we performed molecular diagnostic analyses on P. nobilis, P. rudis, and bivalve heterologous host species from the island of Sardinia to shed further light on the pathogens involved in the mass mortality. The results support the occurrence of a multifactorial disease and that Mycobacterium spp. and H. pinnae are not necessarily associated with the illness. Indeed, our analyses revealed that H. pinnae is not species-specific for P. nobilis, as it was present in other bivalves at least three years before the mass mortality began, and species of Mycobacterium were also found in healthy individuals of P. nobilis and P. rudis. We also detected the species Rhodococcus erythropolis, representing the first report in fan mussels of a bacterium other than Mycobacterium spp. and Vibrio spp. These results depict a complicated scenario, further demonstrating how the P. nobilis mass mortality event is far from being fully understoo

Mathematical modeling for determining the potency of bovine tuberculin purified protein derivative (P.P.D.)

Bovine tuberculin purified protein derivative (bovine tuberculin PPD) is a preparation obtained from the heat-treated products of growth and lysis of Mycobacterium bovis, strain AN5, purified and solubilized into a liquid preservative, buffered, glycerinate and phenolate, so that the diagnostic product contain at least 20,000 international units. The main characteristic of commercial product is “revelatory power” or potency. The animals infected with Mycobacterium bovis develop delayed hypersensitivity which can be revealed in vivo by skin allergic test. The validation study aims to demonstrate the determination of the potency of the bovine tuberculin PPD, by comparing the reactions produced in guinea pigs sensitized by the intradermal injection of a series of dilutions of the product to be examined with those produced by a reference standard calibrated in international units, it is an appropriate analytical method, reproducible and meets the quality requirements of diagnostic reagents. The paper establishes the performance characteristics of the method considered and identify the factors that influence these characteristics. The diameters of the lesions, directly proportional to the logarithm of the concentration of the tuberculins, measured and calculated using statistical methods (Combistats Soft). The test is not valid unless the confidence limits (P=0.95) are not less than 50 per cent and not more than 200 per cent of the estimated potency. The estimated potency is not less than 66 per cent and not more than 150 per cent of the stated potency. The stated potency is not less than 20,000 international units. The validation procedure includes\ud details on protocol working to determine the potency of the tuberculin A, validation criteria, experimental results, mathematical modeling for determining the potency, inter-laboratory comparisons

Mathematical modeling for determining the potency of bovine tuberculin purified protein derivative (P.P.D.)

Bovine tuberculin purified protein derivative (bovine tuberculin PPD) is a preparation obtained from the heat-treated products of growth and lysis of Mycobacterium bovis, strain AN5, purified and solubilized into a liquid preservative, buffered, glycerinate and phenolate, so that the diagnostic product contain at least 20,000 international units. The main characteristic of commercial product is “revelatory power” or potency. The animals infected with Mycobacterium bovis develop delayed hypersensitivity which can be revealed in vivo by skin allergic test. The validation study aims to demonstrate the determination of the potency of the bovine tuberculin PPD, by comparing the reactions produced in guinea pigs sensitized by the intradermal injection of a series of dilutions of the product to be examined with those produced by a reference standard calibrated in international units, it is an appropriate analytical method, reproducible and meets the quality requirements of diagnostic reagents. The paper establishes the performance characteristics of the method considered and identify the factors that influence these characteristics. The diameters of the lesions, directly proportional to the logarithm of the concentration of the tuberculins, measured and calculated using statistical methods (Combistats Soft). The test is not valid unless the confidence limits (P=0.95) are not less than 50 per cent and not more than 200 per cent of the estimated potency. The estimated potency is not less than 66 per cent and not more than 150 per cent of the stated potency. The stated potency is not less than 20,000 international units. The validation procedure includes\ud details on protocol working to determine the potency of the tuberculin A, validation criteria, experimental results, mathematical modeling for determining the potency, inter-laboratory comparisons

Assessing the status of amphibian breeding sites in Italy: a national survey

The ecological status of 203 amphibian aquatic breeding sites, selected from the national database of the Societas Herpetologica Italica (SHI), was surveyed in the period 2008-2009 to assess their ecological status. Sites were randomly extracted, after stratification by the three biogeographical regions present in Italy, besides Sardinia and Sicily. The field surveys, conducted by professionals, amateurs and volunteers, showed that since 1979 about 11% of the sites were destroyed or no more suitable for the reproduction of amphibians that bred in the same site in the past. The percentage of destroyed or altered sites was 8%, both in the Mediterranean and Alpine biogeographical regions, and 15% in the Continental one. However, there were no statistical significant differences among the regions, suggesting that the rate of amphibian site loss was similar in different parts of Italy. This nation-wide monitoring project demonstrated that in Italy, during the last thirty years, a relevant proportion of amphibian breeding habitats has been destroyed or altered. The main cause of site alteration were land reclamation and water extraction