Infection of brown shrimp, Penaeus aztecus ives by Prochristianella penaei kruse (cestoda: trypanorhyncha) in Southeastern Louisiana

Abstract

The plerocecus of the trypanorhynchan cestode, Prochristianella penaei was found to be a common parasite of commercially important shrimp (including Penaeus aztecus and P. setiferus) in southeastern Louisiana. During June and July, 1967, the cestode was found in 42% of 971 subadult and large juvenile P. aztecus (61 to 134 mm in total length) taken weekly from three different estuaries. Infection of specimens from Lake Pontchartrain varied between 18% and 50% without definite pattern, but in Lake Borgne it rose suddenly from 38% to 88% and leveled off. In the delta complex west of the Mississippi River, it increased at a slower but more regular rate and reached a maximum of 63% in the last sampling week. Growth of infection in the latter areas may reflect the increasing abundance of at least one other host. The ecology of these areas was considered relative to possible recruitment of the small first intermediate host, and habits of the definitive host, Dasyatis Sabina, were examined for possible leads. Results also indicated that host population were not uniformly distributed within a given system. No correlation was found between salinities of complementary stations and corresponding differences in shrimp infection. Instead, infection varied inversely with particle size indicating that coarser substrates might be limiting to certain hosts, possibly shrimp..