Serological studies on oil sardine (Sardinella longiceps) and mackerel (Rastrelliger kanagurta)

An antiserum was raised in a rabbit against 0 panel red cells of mackerel. The erythrocytes of oil sardine and mackerel were tested against human blood typing sera anti A and B and also the test serum of rabbit which revealed the presence of antigens A and B. In addition, an antigen common to both the fishes and human A, B and 0 panel red cells was noted but not identifiable. The blood group B did not manifest itself clearly either in oil sardine or mackerel. The blood groups A, AB and 0 indicated the existence of genetically different groups of oil sardine and mackerel. Isoagglutinin tests revealed the presence of a reciprocal relationship with antigens A and B in both these fishes.

Immunodetection of planktonic algae

Interest in the identification and characterisation of cyanobacteria and dinoflagellates in aquatic environments is increasing rapidly due to the perceived roles of these organisms in primary production and nuisance aspects in terms of water treatment and public health. Techniques for the identification and quantification of these organisms currently are limited, and the application of molecular approaches provides fundamental taxonomic information and techniques of practical value. Antigenic properties of algal cells may be useful taxonomic markers. Immunodetection techniques utilise the specificity of the antibody/antigen association as a probe for recognising and distinguishing between microorganisms according to their cell- surface chemistry. Immunofluorescent detection of unicellular cyanobacteria and dinoflagellates has been studied with success in marine and freshwater ecosystems and a range of techniques and results are presented and discussed. The most recent advances in the study of planktonic algae have come with the application of continuous flow cytometric methods (CFC). Flow cytometry makes use of the autofluorescence properties of the algal cells, which alone can be used to demonstrate their presence and permit their quantification in natural water samples. When used in conjunction with immunolabelling techniques, the potential of CFC analysis is broadened to study the serological/strain composition of plankters in natural populations. Changes in algal strains represented within and between waters over periods of time are reported and discussed, along with the ecological issues thus raised.

Electrophoretic and immunotaxonomic studies of three species of marine gastropods from Portonovo coast with reference to population management

Electrophoretic and serological studies of foot muscle protein of three species of Cerithiacea (Telescopium telescopium, Cerithidea fluviatilis and C. obtusum) were carried out to understand their relationships. Living specimens were collected from mud flats and mangrove swamps off Portonovo. Polyacrylamide electrophoresis of proteins from foot muscle extract of T. telescopium, C. fluviatilis and C. obtusum showed that the former had a different densitometric profile as well as more number of protein bands; but the later two species showed a closer related pattern as well as lesser number of protein bands. At the same time these two species are distinguished from each other in their total number of bands and Rf values. Immunological studies using micro-Ouchterlony double diffusion tests which absorbed antiserum indicated that C. fluviatilis and C. obtusum were more closely related as revealed by an identity reactions than T. telesopium as shown by non-identity reactions. Results are discussed in relation to ecological and morphological adaptations

Isolation of Salmonella agona (4, 12:f, g, 5:-) from commercial frozen boiled clam meat

Details are given of the morphological, biochemical and serological characteristics of a specimen of Salmonella agona isolated from a sample of frozen boiled clam meat (Villorita cyprinoides) processed in a factory at Cochin. Possible association of this serotype with human salmonellosis is considered briefly.