Diseases caused by pathogenic microorganisms are an ever present risk to animals in both captive and free-ranging populations. The endangered status of the Florida manatee (Trichechus manatus) has focused a great deal of interest on its biology and medical management. Initially since no manatee-specific reagents were available, protein G conjugated to alkaline phosphatase was used to examine the interaction of manatee sera with marine anaerobes isolated from manatees during necropsy or routine physical examination. The impetus for these early studies was a series of case reports associating Clostridium difficile infections with colonic disorders of orphan manatee calves. Briefly, sera of 24 manatees were examined for antibodies against 29 anaerobic marine bacteria by an enzyme-linked immunosorbent assay (ELISA) utilizing protein G-alkaline phosphatase conjugate as the secondary reagent. Results from these experiments demonstrate which clinical bacterial isolates react with manatee sera, which manatee sera react with most of the clinical isolates, and which of the clinical isolates are most closely related serologically to C. difficile. Furthermore, these experiments demonstrated the efficacy of protein G as a secondary reagent in an ELISA format with manatee sera. Current work confirms the utility of protein G in binding and purifying manatee IgG for generating both anti-manatee mouse monoclonal as well as rabbit anti-manatee polyclonal antibodies. Results from experiments using these manatee-specific reagents in detecting antibodies to the red tide dinoflagellate, Gymnodinium breve, will be discussed.

(This work was supported by the State of Florida Department of Environmental Protection and the Sirenia Project, National Biological Survey.)