Abstract

Erysipelothrix rhusiopathiae isolated from a septicemic Pacific bottlenose dolphin (Tursiops gilli) provided by the Navy Marine Mammal program was used to perform an enzyme linked immunosorbent assay (ELISA). The ELISA was developed using Frasch (Frasch and Chapman, 1972) extracted antigen of the isolate as the ELISA capture antigen. An indicator system was developed consisting of biotin labeled rabbit anti-Tursiops truncatus IgG, alkaline phosphatase labeled avidin, and para-nitrophenyl phosphate as the chromogenic substrate. The ELISA was used to evaluate anti-E. rhusiopathiae titers in a series of serum samples from four populations of Atlantic bottlenose dolphins (Tursiops truncatus). The four dolphin populations consisted of free ranging dolphins from South Carolina living among heavy human traffic, free ranging dolphins from Florida living among low human traffic, captive dolphins from California living among heavy human traffic, and captive dolphins from the Bahamas living among low human traffic. Results revealed that the majority of the total number of individuals (42%) tested expressed a titer of 1/1,000. Within the individual populations the major titer varied. The major titer (27%) for South Carolina's population was1/10,000, while 40% of Florida's population had 1/100 as its major titer. The Bahamas and California both had 47% of their individuals with a titer of 1/1000. Results further showed that wild dolphins and dolphins living among heavy human traffic had the greatest number of individual dolphins expressing higher titers, while captive dolphins and dolphins living among low human traffic had the greatest number of individual dolphins expressing lower titers.