Reptiles

	Reptiles have three-chambered hearts, except crocodiles (essentially complete interventricular septum)
	Glottis is easily visualized in the floor of the mouth
	Crocodilians have a basihyal valve that seals the oral cavity from the glottis, allowing them to hold prey while submerged
	Snakes and lizards have a forked tongue to convey scent to the vomeronasal organ
	Most snakes have vestigial left lungs and elongated right lungs
	Many snake lungs end in air sacs
	Snakes have a renal portal system similar to that of amphibians
	Snakes and lizards have hemipenes

	Some reptiles lay eggs, some bear live young
	Reptile eggs must be kept in a fixed position after laying, as the embryo is attached

	Enclosures commonly glass or plastic
	Aquatic reptiles do not require dechlorinated water
	Substrates: hardwood shavings, paper, indoor/outdoor carpet
	Need hiding places and resting places
	Many like to soak in their water dishes, so plan accordingly
	Snakes feed on whole prey; some are very fastidious
	Lizards and turtles are carnivorous, omnivorous or herbivorous depending on species Anoles eat insects Iguanas eat vegetation Aquatic turtles eat pelleted diets or whole minnows Box turtles eat dog food, fruit and veggies Crocodilians eat whole prey or pelleted diet
	Reptiles do well on standard light/dark cycles; turtles and lizards require UV light (280-320 nm) to convert vitamin D3
	Require a temperature gradient in the enclosure
	Wash cages weekly; do NOT use phenolics!
	Blood sampling from ventral tail vein in lizards and snakes, jugular or caudal vein in turtles (may need ketamine), or cardiac puncture in some snakes and crocs under anesthesia
	Obtain samples for parasitology by flushing with small catheter in upper GI and lower GI tracts
	Anesthesia: isoflurane; turtles need ketamine (20-40 mg/kg IM) Ketamine (5-10mg/kg) plus medetomidine (0.1-0.2mg/kg) IM works well with good recovery using atipamezole (0.5-1mg/kg IM); probably won't be surgically anesthetized but simple incisions can be made and they can be intubated{4501}. In reptiles, onset of anesthesia proceeds from cranial (forelimbs) to caudal (hindlimbs).{4501}
	Surgical incisions must be paramedian to avoid ventral abdominal vein in lizards and snakes (between scales); use non-absorbable suture and remove in 6 weeks; use everting patterns
	Analgesics: no data, but try butorphanol (0.2mg/kg IM) or buprenorphine (0.005-0.02 mg/kg IM q 24-48hr)

	Infectious stomatitis (mouth rot) in reptiles usually caused by Pseudomonas and Aeromonas is very painful and may progress to osteomyelitis and death; debride and treat with chlorhexidine and antibiotics
	Anorexia usually secondary to advanced amoebiasis or other protozoans, infectious stomatitis, intestinal obstruction, inappropriate size or type of food, or cool temperature
	Vomiting or regurgitation from handling or stress after feeding, cool temperature; in snakes think of Entamoeba invadens (treatable) or cryptosporidiosis (fatal)
	Constipation usually secondary to intestinal obstruction from impacted skeletal remains, or from metabolic bone disease with vertebral fracture and nerve damage in lizards; treat with warm water enemas
	Vitamin A deficiency in young turtles on wrong diet presents with swollen closed eyes and open mouth breathing (from respiratory epithelial hyperplasia); secondary bacterial infection is common; in anoles it presented as swollen closed eyelids and thickened lips with ulcers on the margins (see below)
	Retained spectacles in snakes, possibly with mite infestation
	Metabolic bone disease in young iguanas caused by insufficient UV light and calcium-poor diet; animals appear anorexic and lethargic with "fat" legs or fractures; treat with calcium and vitamin D3 and correct light and diet
	Patchy skin shedding is normal in lizards and turtles, but abnormal in snakes
	Blister disease: bacterial infection in wet, dirty environment causing vesicles on ventral surface; similar to "shell rot" in turtles which can be debrided and kept clean
	Antibiotic choices in reptiles should be bactericidal because they're usually in bad shape by the time you figure it out; choose from enrofloxacin (5mg/kg IM q48h), ceftazidime (20mg/kg IM q 72h), trimethoprim sulfa (30mg/kg IM q 48h), amikacin (2.5mg/kg IM q 72h) (nephrotoxic, give fluids)
	Parasites Nematodes: fenbendazole (50-100 mg/kg PO repeated in 2 wks) and ivermectin (0.2mg/kg PO repeated in 2 wks) but ivermectin is toxic to turtles Cestodes: praziquantel 5-8mg/kg PO repeated in 2 wks Amoeba and Trichomonas: metronidazole 100mg/kg PO repeated in 2 wks; do not use in tricolor king snakes or indigo snakes Ectoparasites: ivermectin and Vapona strips or pyrethrin spray wiped on the reptile
	Euthanasia: overdose of MS222 or pentobarbital intra-coelomically; physical methods not usually applicable due to tolerance to anoxia; exsanguination or decapitation of anesthetized turtles is okay

During a 5 year period, 16 freshwater turtles (Trachemys scripta elegans and Chrysemys picta) were purchased for research purposes and died spontaneously. Clinical signs included lethargy, constant swimming sideways, hemiplegia, and necrotic lesions on the carapace. The abdominal cavity in some turtles contained clear to red-tinged fluid; the liver had small areas of necrosis, and fibrin adhered to the capsule; and nematode parasites were observed in a majority of the gastrointestinal tract. Other lesions observed included cardiac necrosis, pneumonia, hepatic lipidosis, and pancreatic and splenic necrosis. Fluke eggs were found in most organs and were associated with small blood vessels which had villus-shaped intimal proliferation in the aorta and mesenteric arteries. There were large areas of necrosis and hemorrhage in the pancreas, spleen, liver and lung. A granulomatous response was also observed in the submucosa of the small intestine. Fluke eggs were seen in vessels of the brain. Eggs are deposited as the adults migrate through the tissues. The migration of the adults and the eggs elicit an acute inflammatory response. The pathogenicity of the fluke Spirochis parva is related to the secondary infections caused by widespread egg deposition and blockage of small vessels in the small intestine causing necrosis and bacteremia. The diagnosis of this fluke is made from egg identification since adults are difficult to find. The eggs can be found by compressing lung tissue between a glass slide and cover slip or by fecal examination. This parasite requires a snail as an intermediate host to complete the life cycle. Treatment is Praziquantel, 8 mg/kg orally, which is a safe anthelmintic to use in turtles. However, this drug crosses the blood brain barrier.{3633}