Clinical Presentation, Treatment and Outcome of Rhododendron (Grayanotoxin) Intoxication in Three Mediterranean Tortoises
Clinic for Small Mammals, Reptiles, and Birds, University of Veterinary Medicine Hannover, Hannover, Lower Saxony, Germany
Three adult Mediterranean tortoises, one spur-thighed tortoise (Testudo graeca) and two marginated tortoises (Testudo marginata), were presented with severe neurological signs after suspected ingestion of grayanotoxins. In the case of the spur-thighed tortoise, parts of flowers and leaves of Rhododendron spp. were found next to the tortoise enclosure and ingestion plant parts that had been blown into the enclosure was suspected by the owner. Both marginated tortoises were observed sitting in an enclosure full of rhododendron flowers and leaves, one of them vomited two whole blossoms and therefore both were highly suspected to have ingested massive amounts of those plant parts. All three tortoises showed different degrees of salivation, weakness and lethargy, two developed tonic extensor seizures with hind limb extension. Treatment included subcutaneous administration of prednisolone (initially), daily fluid therapy and furosemide as well as repeated administration of charcoal and water via gastro-esophageal tube. Radiographs of the two marginated tortoises, where ingestion on the same day or the day before was highly suspected, showed multiple suspicious structures within the stomach. After initial treatment with subcutaneous prednisolone, furosemide and fluid therapy, gastroscopy for the removal of the flowers and leaves was initiated under general anesthesia. In both Testudo marginata, partial or total removal of flowers and leaves via gastroscopy was possible, and followed by intensive care including repeated administration of charcoal, water and tube-feeding. All three animals survived the ingestion of flowers and other parts of Rhododendron spp., which seem to be highly toxic for tortoises.