Wild turtles often harbor small numbers of parasites, though they do not always cause health problems for the turtles. Captive turtles kept in unclean cages and in frequent contact with their waste, can develop high parasite loads and illness. Anorexia, depression, lethargy and intestinal disturbances are all signs of internal parasites, but some external parasites are visible to the naked eye. If your turtle displays symptoms of parasites, you should consult with your veterinarian to establish a parasite treatment program.
Turtles with parasites may only exhibit mild, vague symptoms -- or they may be completely asymptomatic. Have your turtle examined by a reptile-oriented veterinarian when you first acquire him, and otherwise anytime he exhibits unusual behaviors. The vet will examine your turtle’s feces for signs of roundworms, hookworms, tapeworms and whipworms. Additionally, the vet may check your turtle’s blood chemistry and look for evidence of flukes. After diagnosing which, if any, parasites are infecting your reptile, the vet will prescribe appropriate medications to treat any parasite infestations.
Aquatic turtles do not often get mites, ticks and similar external parasites, but they are susceptible to leeches. In the wild, leeches attach themselves to turtles living in ponds and creeks -- so wild-caught specimens frequently have leeches attached to their heads, legs or necks. If you see leeches on your turtle, take him to the vet to have them removed; if a large wound is present, the vet may prescribe antibiotics to treat possible infection. Be vigilant with turtles housed outdoors and inspect them for leeches regularly. While common in terrestrial turtles, aquatic turtles rarely harbor blowfly larvae.
Anorexia, Depression and Lethargy
Captive urtles who appear depressed or lethargic may be harboring high parasite loads. Internal parasites can be taxing on your turtle's immune system, preventing them from behaving as they normally would and resulting in their burrowing or basking for long periods of time. Anorexia is a common symptom of parasitized turtles. If your pet begins refusing his favorite food items or is not interested in food at all, parasites could be the reason. Meanwhile, new pets may take a few days to acclimate to their new surroundings before eating.
Because turtles usually defecate in the water, it can be difficult for you to monitor their waste. Blood or unusual discharges from your turtle’s cloaca can indicate a parasite problem. While they are not visible to the naked eye, most parasitic worms release eggs with their host’s feces; their identification requires a microscope and the skill to identify present eggs. Because turtles excrete parasite eggs in the tank’s water, any other animals living in the tank may become infected as well. Because of this, it is advisable to treat all of the turtles in the aquarium at the same time; otherwise, a cycle of infection, treatment and reinfection is likely to occur.
Weight loss can indicate a serious parasite infestation. As it can be difficult to judge this visually with a turtle, it is important to track your turtle’s weight over time. Juvenile turtles should steadily gain weight over time, while adults should maintain a steady weight if they are healthy.