Drury R. Reavill and Chris Griffin

Species Submitted for Laboratory Evaluation

Chelonians were the smallest group (14%) presented for necropsy and biopsy evaluation. The species included, in descending order of frequency, are as follows: Russian Tortoise (Testudo horsfieldii), Red-eared Slider (Trachemys scripta elegans), turtle (not specified), Malayan Box Turtle (Cuora amboinensis), box turtle (Terrapin spp.), African Side-neck Turtle (Pelomedusidae family), Marginated Tortoise (Testudo marginata), and Red-footed Tortoise (Chelonoidis carbonaria).

Lizards were the next largest group evaluated (31%). The species of lizards examined by necropsy and, infrequently, biopsy samples included the popular Leopard Gecko (Eublepharis macularius) (33%) and Bearded Dragon (Pogona vitticeps) (23%). The remaining species in descending numbers were Green Water Dragons (Physignathus cocincinus), common Green Iguana (Iguana iguana), gecko (not specified), anole (family Polychrotidae), Savannah Monitor (Varanus exanthematicus), lizards (not specified), Emerald Swift (Sceloporus malachiticus), Blue-tongued Skink (Tiliqua sp.), chameleon (not specified), and Ameiva (family Teiidae).

Snakes were the largest group evaluated (34%). The species of snake submitted for pathologic examination included, in descending order of frequency, are as follows: Ball Python (Python regius), “Red-tailed” Boa (Boa constrictor constrictor), Cornsnake (Elaphe guttata), snake (not specified), Ribbon Snake (Thamnophis sauritus), Milk Snake (Lampropeltis triangulum), Garter Snake (Thamnophis spp), and Green Tree Python (Morelia viridis).

Although many of the lizards and snakes were young animals (evidenced by size and the occasional yolk sac remnants observed on gross postmortem examination), the age of many of the chelonians was not determined (Figure 2-1).

The gender of each animal submitted was determined in most complete postmortems; however, there were rarely noted disease conditions linked to the reproductive tract. This is not unexpected given the age of the animals for sale in the pet trade.

These necropsy percentages may not exactly reflect the types of species seen in a busy private practice because submission depends on not only the perceived value of the animal but also the value of the postmortem findings.

Husbandry-Related Conditions

Deficiencies in husbandry are overwhelmingly the most common factor causing illnesses in captive reptiles. Overcrowding, exposure to sick animals (and their body fluids/excrements), poor nutrition, improper thermal gradients, and many other aspects of reptile care may constitute the basis of many of the illnesses that plague reptiles in the pet trade today (Figure 2-2). Many of the most popular reptiles are shipped to pet stores in containers that are either too small or have too many other of the same (or different) species and minimal, if any, thermal regulation. Many may be shipped from a breeder to a distribution center before being sent to a pet store, and many of these animals (usually younger animals) may not feel like eating for several days during this transition period. The basics of thermal support, humidity, feeding opportunities, hiding options, and a reasonable animal-to-space ratio may not always be provided, even within a pet store setting. All of these factors may trigger new conditions or flare-up of preexisting conditions. Examples may include adenoviral or coccidial infections in Bearded Dragons and cryptosporidial infections in Leopard Geckos.¹

The most important aspects of diagnosing sick reptiles in the pet store rely on the training of the employees/caretakers. Good observational skills and an understanding of basic health and behavior are paramount to early detection and evaluation of these reptiles in the veterinary hospital. Seeing a sick reptile 1 or 2 days into an illness often affords a much better prognosis than attending to a sick reptile 14 to 21 days into an illness.

When possible, diagnostics should be performed. These should include (but not be limited to) a thorough physical examination, fecal parasite examinations (e.g., direct, float, and/or special stains), laboratory analysis (complete blood count/chemistry profile) and histology/cytology, when indicated (Figure 2-3). Advanced diagnostics including cultures (bacterial and fungal), imaging (e.g., radiographs, ultrasound, magnetic resonance imaging [MRI], and computed tomography [CT]), and molecular testing (including polymerase chain reaction [PCR] testing) may also be indicated. Once a diagnosis is obtained, specific treatments, when available, should be recommended and pursued. While test results are pending, supportive care (including environmental support, fluids, nutritional [caloric and vitamin] support, and antibiotics, among others) should be instituted, as needed.

Common Clinical Diseases

Many of the common presentations that are seen in practice are manageable, and many of these animals that are seen are not included in the necropsy numbers listed earlier in the chapter. The most common conditions that present are as follows:

In tortoises, poor nutritional status, failure to thrive, poor shell development, and anorexia are common conditions (Figure 2-4).

In lizards, parasites include coccidia, pin worms, and protozoans in Bearded Dragons, cryptosporidia are found in Leopard Geckos, and protozoans in most species. Gram-negative enteritis are common in many species. Nutritional secondary hyperparathyroidism (resulting in hypocalcemia and associated changes) is common in iguanas and has also been seen in Leopard Geckos (Figure 2-5). Ocular issues, including conjunctivitis from environmental factors (e.g., reptile bark) or retained sheds (possibly from humidity/hydration issues), are also common (Figure 2-6). Stomatitis is commonly seen in Water Dragons, Blue-tongued Skinks, Bearded Dragons, and Leopard Geckos. Adenovirus in Bearded Dragons may be more common than reported, and concurrent infections with adenovirus and parasites (e.g., coccidia and cryptosporidia) may lead to more severe signs and a greater chance of mortality.² Failure to thrive, a catch-all term used in captive animals to describe illnesses that are not specifically identified but compromise the animal, is seen in more “sensitive” species (e.g., most chameleon species, some geckos, uromastyx species, and in some areas, water dragons) (Figure 2-7).