A WHOLE-OYSTER PROCEDURE FOR DIAGNOSIS OF PERKINSUS-MARINUS DISEASE USING RAYS FLUID THIOGLYCOLATE CULTURE-MEDIUM

Diagnosis of Perkinsus marinus disease of eastern oysters Crassostrea virginica has been routinely accomplished by incubating oyster tissues in a fluid thioglycollate medium described by Ray in the early 1950s. At least three modifications of the technique are available with appl ications to different diagnostic needs. Of these, the quantitative who le-oyster technique is potentially the most valuable because it includ es all oyster tissues and does not rely on subjective estimates of int ensity. A variety of protocols and approaches were examined in an atte mpt to develop a standardized procedure for quantitative whole-oyster diagnosis that optimizes sensitivity, specificity, precision and accur acy. A recommended procedure, with possible variations, is presented h ere with the expectation that its presentation will foster further ref inement and improvement. We conclude that the recommended whole-oyster diagnostic technique is capable of providing reliable quantifications of prevalence and intensity and has great potential for examining cor relations of total P. marinus body burdens with measurements of oyster biology and for evaluating or calibrating other diagnostic techniques .