Evaluation of two commercially available immunological kits for the diagnosis of Helicobacter spp. in bottlenose dolphins (Tursiops truncatus).

Helicobacter pylori is considered to be responsible for the most common gastric infections in humans worldwide. In animals, other Helicobacter species are linked to gastritis with and without the presence of ulcers in their respective hosts. Moreover, gastric ulcers have been reported for decades in wild and captive dolphins. Clinical signs include lack of appetite, anorexia, abdominal tenderness, depression, and occasional unresponsiveness. In this study, serum and stool of nine bottlenose dolphins from Loro Parque collection Tenerife, Spain were examined for the presence of Helicobacter spp. The aim of our study was to evaluate the use of two commercially available kits for the detection of H. pylori in humans: a stool antigen immunoassay (Letitest H. pylori CARD) and a Western blot assay (EUROLINE-WB H. pylori) that were adapted to identify specific Helicobacter spp. antibodies in the tested Loro Parque bottlenose dolphin collection. The utility of these diagnostic kits for their application in dolphins is demonstrated, and their use in the future for the diagnosis of Helicobacter spp. in both wild and captive dolphins is proposed in this study.

Development of an indirect immunofluorescence technique for the evaluation of generated antibody titers against Erysipelothrix rhusiopathiae in captive bottlenose dolphins (Tursiops truncatus).

Erysipelothrix rhusiopathiae is the causative agent of erysipelas, a disease of many mammalian and avian species, mainly swine and turkeys. In cetaceans, erysipelas is considered to be the most common infection in juvenile individuals, which have not been vaccinated. Moreover, the disease manifest in both forms, the dermatologic and the acute septicemic forms, has been reported in various species of dolphins and whales. It is difficult to diagnose erysipelas by currently available approaches. Moreover, it is mainly based on culture methods and also PCR methods, which are currently being developed. At the present stage, prophylactic approaches are based on antibiotic therapy and vaccination mostly with porcine erysipelas vaccines. In the present study, an Indirect Immuno Fluorescence method for the detection of dolphin antibodies levels against E. rhusiopathiae was developed and applied in two different groups of captive bottlenose dolphins (Tursiops truncatus) from Loro Parque (Tenerife, Canary Islands, Spain) and L'Oceanogràfic de Valencia (Valencia, Spain) in order to check the tittering levels of antibodies after application of porcine erysipelas vaccines in the studied dolphins.

Development of an indirect immunofluorescence technique for the diagnosis of toxoplasmosis in bottlenose dolphins.

The diagnosis of toxoplasmosis is often complicated by the lack of specific clinical symptoms or postmortem features, in humans and other animals. The only diagnostic test described so far for the serological diagnosis of Toxoplasma gondii in marine mammals is the modified agglutination test (Dubey et al., Am J Vet Res 48(8):1239-1243, 1987). The development of more sensible and specific immunological techniques requires specific antibodies, which are currently unavailable in the scientific market. Indirect immunofluorescence (IIF) is one of the most widely used methods for the diagnosis of toxoplasmosis in humans (Auer et al., Parasitol Res 12:965-970, 2000). In order to develop and apply this technique to the bottlenose dolphin (Tursiops truncatus), immunoglobulins were firstly purified using ion-exchange chromatography. The purified immunoglobulins were then injected in New Zealand rabbits in order to obtain polyclonal antibodies. These antisera were validated by the IIF technique, using as controls serum samples of dolphins infected by Toxoplasma. The results were visualized using antirabbit IgG labeled with fluorescein. This newly developed and specific serological assay was then tested with the dolphin collection of Loro Parque, Tenerife, Spain (group I), and L'Oceanogràfic of Valencia, Spain (group II). The obtained results in this study showed that none of the dolphins from group 1 were infected by T. gondii and two animals were positive in group 2. Furthermore, we conclude that this study has produced antibodies with high specificity against dolphin immunoglobulins and an IIF method which may be used as immunological diagnostic tools, especially for the serological diagnosis of toxoplasmosis.