Snakes

Snakes are popular reptile pets, and there has been a resurgence in their popularity with the breeding of a variety of color morphs. A huge number of species are available in the pet trade, but the commonly kept species are listed in Table 11-1.

The internal anatomy of a snake is shown in Figure 11-1 (see also “Radiography” in Mus­culoskeletal Disorders).

Consultation and handling

A healthy snake should be reasonably alert and responsive to touch. If it is flaccid or exhibit­ing CNS signs, such as “star-gazing,” it is likely to be suffering a septicemia, poisoning, or possibly a protozoal infection such as Acanthamoeba.

Start the examination at the head and work backward. Larger snakes such as the pythons and boas may require one or more people to hold them while you perform your examina­tion. A gag is usually required to open the mouth—wooden spatulas work reasonably well and are less traumatic than metal equivalents. Do not encourage staff or clients to drape large constricting snakes across the shoulders and around the neck because if the snake feels inse­cure, it may well tighten its grip unexpectedly.

Venomous snakes require specialist handling equipment and should only be handled by a competent herpetologist or while under an anesthetic.

Microchipping

• Left nape of the neck, subcutaneously placed at twice the length of the head from the tip of the nose

• Skin closure is achieved either by suture or with tissue glue.

Sexing

Many snakes are not obviously sexually dimorphic or dichromatic. The safest and most popular way of sexing monomorphic snakes is by “probe-sexing," in which a small, well- lubricated and blunt-ended rod is gently inserted into the cloaca and then directed caudally to one side of the midline so as to slot into the inverted hemipenes of the male, if present. If female, the probe will only travel a few subcaudal scales, while in a male it will pass a significant distance (Fig. 11-2).

Nursing care

Provide an appropriate environment, including provision of:

1. Optimal temperature (basking lights, heat mats, etc., to allow thermoregulation). Use of max-min thermometers will assist in monitoring temperature ranges incumbent reptiles are exposed to.

2. Full-spectrum lighting appears to be relatively unimportant for snakes with some exceptions (e.g., rough green snake—Opheodrys aestivus).

3. Humidity

4. Ventilation

5. Easily cleaned accommodation; use paper substrate and disposable/sterilizable hides and other vivarium furniture (Fig. 11-3).

6. Keep individually to minimize intraspecies stress and competition for resources.

Fig 11-2. Sexing snakes.

Fig 11-3. Clinical vivarium setup for snakes (lighting is optional—see text).

Fluid therapy

See “Fluid Therapy” under Nursing Care in Chapter 10.

Dehydrated snakes typically show an increase in skin tenting and folding, especially lon­gitudinal folding. Daily bathing in shallow, warm water is often beneficial; it encourages many snakes to drink as well as defecate and urinate.

Fluids administration in snakes

1.

2. Esophagostomy tubes can be used in some cases.

3. Intracoelomic fluids can be given, but try for the ventral tail vein or even the palatine vein.

4. A jugular cutdown can be performed if the snake is anesthetized and a catheter inserted, and small volumes may be administered as a bolus into the ventricle.

5. Small volumes may be given per cloaca.

--

Nutritional support

Liquidized normal diet or proprietary support diets can be used, given either by stomach tube or by esophagostomy tube. Force-feeding of prey species may prove traumatic in inex­perienced hands.

Analgesia

See “Analgesia” in Chapter 10.

Anesthesia

1. For general notes, see “Anesthesia” under Nursing Care in Chapter 10.

2. Induction: Propofol at 10 mg/kg IV into the ventral tail vein or 1.0 to 2.0 mg/kg intraventricular.

3. Otherwise as for lizards.

Skin disorders

Normal ecdysis in snakes

Shedding in snakes is a cyclical event, with synchronous replacement of the whole epidermis at the same time. Snakes should shed their skin in one continuous sheet, starting rostrally, and any deviation from this should be considered abnormal. Ecdysis is under both environ­mental and endocrinologic control. Ecdysis in snakes follows the following sequence:

1. Resting phase. There is only one stratum corneum and stratum germinativum.

2. The stratum germinativum undergoes intense proliferation to form a new stratum corneum, but there is no outward visible change in the snake.

3. The new stratum corneum begins to differentiate and keratinize. At this point there is a slight dulling of the skin of the snake, and the spectacle may appear slightly cloudy.

4. A new layer—the stratum intermedium—is now apparent. This lies between the inner and outer layers of strata cornea. The epidermis is thickest now, and so the snake's colors are at their dullest; the spectacle is cloudy.

5. The stratum intermedium is dissolved away by lymph-carrying enzymes—this leaves a cleavage plane between the two strata cornea. The snake's colors will be seen to brighten and the spectacle will clear.

6. Approximately 4 to 7 days after the spectacles clear, the outer stratum corneum is shed.

Differential diagnoses of skin disorders

See also Skin Disorders in Chapter 10.

Shedding difficulties (dysecdysis)

• Humidity too low

• Other environmental problems (e.g., incorrect photoperiod, temperature, nutrition)

• Lack of cage furniture to allow initiation of shedding

• Snake mites (Ophionyssus natracis)

• Scarring or other underlying dermal disease

• Hyperthyroidism (excessive, repeated skin shedding)

• Secondary bacterial and fungal infections common

Fig 11-4. A young anerythristic corn snake caught up in duct tape used on the electrics in a home-made vivarium.

Pruritus

• Snake mites

• Irritation; large numbers can be associated with anemia, dysecdysis, depression, and anorexia.

Erosions and ulceration

• Rodent bites

• Adhesive tape (Fig. 11-4)

• Blisters and sores, especially on the ventral scales (ventral dermal necrosis, vesicular dermatitis, blister disease); typically bacterial—Pseudomonas spp., Aeromonas spp., Proteus spp.

• Mycotic dermatitis (e.g., Chrysosporium anamorph of Nannizziopsis vriesii, or CANV)

• Kalicephalus larvae

Nodules and nonhealing wounds

• Granulomas (bacterial, mycobacterial, fungal)

• Dermatophilosis (Dermatophilus chelonae)

• Dermatophytosis, include Penicillium spp., Trichophyton mentagrophytes, Candida albicans, Aspergillus spp., Fusarium spp.

• Filarial worms (Oswaldofilaria, Foleyella, Macdonaldius spp.)

• Pentastomids (especially Armillifer armillifer, Porocephalus spp., Kiricephalus spp.—see also Respiratory Tract Disorders)

• Cestodes: Diphyllobothrium and Spirometra (sparganosis)

Changes in pigmentation

• Petechial hemorrhages: septicemia (see Systemic Disorders), Kalicephalus spp.

Ectoparasites

• Helminths

• Kalicephalus (hookworm) larvae (see Gastrointestinal Tract Disorders)

• Filarial worms (Oswaldofilaria, Foleyella, Macdonaldius spp.)

• Cestodes: Diphyllobothrium and Spirometra (sparganosis)

• Arthropods

• Ticks (Aponomma latum and Amblyomma spp.; see Kenny et al 2004)

• Snake mite (Ophionyssus natracis)

• Pentastomids (e.g., Raillietiella)

Burns

• Many snakes are thigmotherms; powerful unprotected heating equipment can cause severe localized burning of the dermis.

Spontaneous rupture of skin

• Hypovitaminosis C

Neoplasia

• Squamous cell carcinoma

• Fibrosarcoma

• Chromatophoroma (malignant)

• Liposarcoma

• Lipoma (especially corn snakes, Elaphe guttata)

• Papillomatosis (especially boas)

Findings on clinical examination

• Dysecdysis

• One or more patches of retained skin. In some areas the skin will appear dull and thickened where several layers of skin have built up over successive dysecdysis episodes. In some cases rings of unshed skin may form bands around the tip the tail. As these dry they constrict, acting as tourniquets and compromising blood flow to the extremity. The spectacles may be retained (see Ophthalmic Disorders).

• Small mites found on snakes; tend to accumulate under the scales, the postorbital area, labial pits, and any skinfolds around the mouth or cloaca. Snake may spend much of the time submerged in water bowl (snake mites).

• Large arthropod parasites (ticks)

• Red patches resembling bruising (hemorrhages—septicemia, trauma)

• Anemia (heavy ectoparasitic infestations)

• Swellings (neoplasia, subcutaneous parasites, such as filarial nematodes, but also consider coelomic disorders)

Investigations

1. Cytology (fine-needle aspirate)

a. Fecal or sputum examination

b. Pentastomid eggs

2. Routine hematology and biochemistry

a. Thyroid levels (see Endocrine Disorders)

3. Aseptic collection of samples

a. Culture and sensitivity

4. Endoscopy

a. Adult pentastomids (look like strange caterpillars)

5. Radiography

6. Biopsy

7. Ultrasonography

TreatmentZspecific therapy

• Dysecdysis

• Moisten the affected areas to loosen the retained skin from the underlying epidermis. If the skin feels firmly attached, leave it and try again after further moistening.

• Placing the snake in a warm, damp towel, pillowcase, or duvet cover (for large snakes) provides rehydration, lubrication, and soft, slightly abrasive surfaces against which to rub. Enforced bathing in warm water may also help, but beware the possibility of drowning.

• Retained spectacular scales are best removed using a damp cotton bud (see Ophthalmic Disorders).

• Vitamin A at 1000 to 5000 IU/kg IM will often trigger a further shed, allowing a closer management of the sloughing procedure such that both the old shed and the new are removed.

• Hyperthyroidism

• Antithyroid drugs (e.g., methimazole at 2 mg/kg PO s.i.d.)

• Possibly try other antithyroid drugs such as carbimazole.

• Partial or complete thyroidectomy may also be appropriate depending on the case.

• Ventral dermal necrosis

• Usually associated with too damp an environment—in semi-aquatic species, it can be initiated by the dermal penetration of hookworm larvae. If left untreated it may progress to a septicemia.

• Treatment is with topical povidone-iodine plus appropriate systemic antibiosis— successful antibiotics include enrofloxacin, amikacin, or even gentamicin.

• Parenteral vitamin A at 1000 to 5000 IU will induce ecdysis, helping to remove much of the infected skin and necrotic material.

• Abscess/granuloma

• Any abnormal swelling should be investigated as a potential abscess or granuloma and may require surgery plus systemic antibiosis.

• Dermatophytosis and fungal mycoses

• Topical chlorhexidine (0.26 mL/L)

• Topical antifungals (e.g., miconazole, terbinafine)

• Ketoconazole at 15 mg/kg PO every 72 hours

• Griseofulvin at 15 mg/kg PO every 72 hours

• Kalicephalus

• Fenbendazole at 25 mg/kg PO weekly for at least 2-3 weeks)

• Filarial nematodes and pentastomids

• Ivermectin at 200 pg/kg SC (toxic to indigo snakes)

• Surgical resection of associated skin granulomas

• Adult pentastomids usually present in lung following extensive tissue migration

• Cestodes

• Surgical removal where feasible

• Praziquantel at 5 mg/kg PO, SC, or IM. Repeat after 2 weeks.

• Adhesive tape entanglement

• The outer epithelial layers may be removed and owners may tear the skin in their efforts to remove the tape.

• Use a solvent (such as halothane or isoflurane) to gradually remove the adhesive; an anesthetic may be required, especially if tape is adhered to the spectacle

(see Ophthalmic Disorders).

• Repair any skin lesions; small lesions can be sealed with tissue glue, larger may require suturing.

• Covering antibiosis if necessary

• Burns

• Debride necrotic material (may require anesthetic) and treat with a topical amorphous hydrogel dressings, such as IntraSite Gel (Smith and Nephew Healthcare Ltd.) and/or povidine-iodine.

• Covering antibiotic or antifungal medication

• If the burns are extensive then fluid therapy should be instigated (see Gastrointestinal Tract Disorders).

• Scarring will eventually result, which may lead to localized areas of dysecdysis; extensive scarring can lead to problems.

• Restrictive scarring may mean that constricting snakes have difficulty completing the behavioral repertoire necessary for normal feeding.

• Spontaneous rupture of skin

• Clean, debride, and suture edges of lesion.

• Supplement with ascorbic acid. May be linked to feeding starved and, therefore, vitamin C-deficient rodent prey

• Ticks

• Individual removal of ticks

• Ivermectin at 200 μg∕kg SC (toxic to indigo snakes). Note: Ticks are vectors for Babesia/Hepatozoon and Ehrlichia-like organisms.

• Snake mites

• Parthenogenetic, so numbers can rapidly build up in vivaria; treatment must include the thorough cleaning of all affected vivaria. What cannot be sterilized with a mild bleach solution (5 mL per gallon) must be disposed.

• Replace usual substrate with paper (changed daily).

• Repeated washing with warm water will physically remove any mites.

• Application of topical fipronil spray once weekly for at least 4 weeks. This is best first applied to a cloth and rubbed over the entire surface of the snake. Fipronil can also be used to treat the environment.

• Injection of ivermectin at 200 μg∕kg SC (Note: Toxic to indigo snakes and chelonia) every 2 weeks will kill those that feed on the snake.

• Commercial imidacloprid (100 g∕L) plus moxidectin (25 g∕L) (Advocate Dog (UK), Advantage Multi (US), Bayer) applied topically at double (32 mg/kg imidacloprid + 8.0 mg/kg moxidectin) to 10-fold dosages (160 mg/kg imidacloprid + 40 mg/kg moxidectin) according to thickness of skin (care with garter snakes Thamnophis spp.—Mehlhorn et al 2005b)

• Cultures of predatory mites (Hypoaspis miles) are commercially available for use in vivaria.

• Linked to septicemia and inclusion body disease (IBD) outbreaks (see Systemic Disorders) as possible vector

• Neoplasia

• Surgical resection

• Chromatophoromas carry a poor prognosis with early metastasis.

• Chemotherapy in reptiles is in its infancy, and most tumors are managed surgically. Accessible cutaneous tumors can be treated by injecting cisplatin directly into the tissue mass on a weekly basis as a debulking exercise.

Respiratory tract disorders

Viral

• Reovirus

• Paramyxovirus 1 and 7

• Ferlavirus (paramyxovirus)

• Ball python nidovirus (Stenglein et al 2014)

Bacterial

• Abscesses

• Granulomas

• Pneumonia/air sacculitis (Fig. 11-5)

Fungal

• Abscesses

• Granulomas

• Pneumonia/air sacculitis

• Cryptococcus neoformans (see also Systemic Disorders and Neurologic Disorders)

• Coccidiomycosis

• Aspergillus spp., A. niger

Parasitic

• Lungworm; Rhabdias spp.

Neoplasia

• Metastases (e.g., from renal carcinomas)

• Chondroma (tracheal)

Other noninfectious problems

• Occluded nostrils

Fig 11-5. Accumulation of purulent material in the lungs of a royal python with pneumonia.

Findings on clinical examination

• Nasal discharge/rhinitis

• Open-mouthed breathing

• “Wet” or unusual respiratory noises

• Discharge around the glottis or inside the proximal trachea. Must differentiate from esophageal discharge (gastritis/enteritis) or secondary to stomatitis. Some conditions may occur concurrently.

• Snake mucus is often thick and tenacious. Mucus may be found as gobbets in the vivarium.

• Snakes have limited ability to cough and the trachea is long so obstructions due to mucus can be serious and may require flushing.

• Occluded nostrils

• Sudden death

Investigations

1. Microscopy

a. Sputum examination (either from mouth, pulmonary lavage, or endoscopic collection)

b. Staining for cytology

c. Gram stain

d. Lungworm eggs and larvae

2. Radiography

3. Routine hematology and biochemistry

4. Serology for Cryptococcus (also consider isolation from lung lavage)

5. Polymerase chain reaction (PCR) and hemagglutination inhibition serology for paramyxovirus 1 and 7 and ferlavirus

6. Culture and sensitivity

7. Endoscopy

8. Biopsy

9. Ultrasonography

10. CT scan

a. Pees et al (2007) in Table 11-2 offer the measurements for computed tomography (CT) examinations of the lungs of healthy Indian pythons (Python morulus) and pythons with respiratory tract disease.

b. Also the mean (±SD) measurements of attenuation in defined lung areas for CT examinations of healthy pythons and pythons with respiratory tract disease (Table 11-3)

Management

• If respiratory disease is severe provide a high oxygen atmosphere.

• Aminophylline at 2.0 to 4.0 mg/kg IM once only

TreatmentZspecific therapy

• Viral infections

• No treatment. Supportive therapy only. Those diagnosed with paramyxovirus or ball python nidovirus should be removed from the collection.

• Bacterial infections

• Appropriate antibiosis. Consider nebulizing.

• Fungal infections

• Ketoconazole at 15 mg/kg PO every 72 hours

• Griseofulvin at 15 mg/kg PO every 72 hours

• Lungworm

• Fenbendazole at 50 to 100 mg/kg PO. Repeat every 2 weeks if necessary. Note: Fenbendazole is metabolized to oxfendazole by the liver.

• Oxfendazole at 68 mg/kg PO. Repeat every 2 weeks if necessary.

• Ivermectin at 0.2 mg SC or PO repeated every 2 weeks for 3 treatments (toxic to indigo snakes)

• Lungworms have a direct life cycle; infective larvae can penetrate the skin or infect via contaminated food and water.

• Chondroma

• Surgical debulking/resection

• Occluded nostrils

• Flush and remove as much debris as possible. May require anesthesia to undertake

Gastrointestinal tract disorders

Disorders of the oral cavity

Note: Mucus may be seen in the mouth as part of respiratory disease and should be differentiated.

Bacterial

• Stomatitis (a variety of gram-negative bacteria, especially Aeromonas, Pseudomonas, Proteus, Morganella)

• Intermandibular cellulitis (Pseudomonas and Aeromonas)

• Venom gland infection (venomous snakes)

Fungal

• Stomatitis

Parasitic

• Ocheostomid trematodes

Neoplasia

• Undifferentiated sarcoma (Abou-Madi et al 1994—see also Systemic Disorders)

Other noninfectious problems

• Fractures (traumatic, pathological)

Findings on clinical examination

• Discharge from the mouth and nares

• Fluid respiratory noises

• Inflammation of the oral and pharyngeal membranes; may progress to ulcerative lesions of the palatine area, the trachea, and the tongue sheath. A diphtheritic membrane may be present (stomatitis).

• Occasionally infection may track up the lachrymal duct, resulting in a subspectacular abscess over one or both corneas (stomatitis—see Ophthalmic Disorders).

• Obvious flat helminth-like parasites in oral cavity (trematodes)

• Gross swelling of the lower jaw and intermandibular area (intermandibular cellulitis)

• Permanent apparent dislocation of the mandible/swelling of one or both mandibles (fracture)

• Abnormal coloring of mucous membranes (icterus, cyanosis)

• Unilateral (or occasionally bilateral) swelling on the face, below eye, and/or along maxilla (venom gland infection/abscess)

Investigations

1. Radiography

a. Stomatitis with possible underlying osteomyelitis

2. Routine hematology and biochemistry

3. Cytology (may need FNA) including Gram staining

4. Culture and sensitivity

5. Endoscopy

6. Biopsy

7. Ultrasonography

TreatmentZspecific therapy

• Stomatitis

• Snakes may not feed while suffering from stomatitis, so may require fluid support such as Hartmann's solution at 15 to 25 mL/kg; nutritional support should be given by stomach tube during this time.

• The stomach tube should be lubricated and coated with appropriate antibiotic to try to prevent iatrogenic spread of infection to the esophagus and further.

Fig 11-6. Taping the jaw of a young boa constrictor with a fractured mandible. Note the esophagostomy tube in place.

• Topical antibiotics plus topical povidone-iodine daily may be sufficient.

• Surgical debridement of necrotic tissue followed by systemic and topical treatments may be required.

• Intermandibular cellulitis

• A synergistic infection of both Pseudomonas fluorescens and Aeromonas hydrophila

• Supportive treatment

• Appropriate antibiotics

• Fractured jaw

• Pathologically weakened bone, or mandibles of small snakes, may be unable to support orthopedic techniques; in some cases taping the jaw closed with strong adhesive plaster (taking care to leave the nares open) accompanied by placement of an esophagostomy tube may allow healing to occur (Fig. 11-6).

• Trematodes

• Often asymptomatic; may cause snake to gape

• Praziquantel at 5 mg/kg PO, SC, or IM. Repeat after 2 weeks.

• Freeze food items (e.g., frogs, fish) for 3 days prior to feeding to eliminate intermediate stages.

• Icterus (see Hepatic Disorders and Cardiovascular and Hematologic Disorders)

• Cyanosis (see Respiratory Tract Disorders)

• Neoplasia (see “Treatment” under Skin Disorders)

• Venom gland infection

• Surgical removal of infected venom gland

• Covering antibiosis

• Note: Removal of both venom glands renders the snake incapable of taking live prey, may alter the shape of the head, and may affect digestion.

Differential diagnosis for gastrointestinal disorders

Viral

• Reovirus (Reavil et al 2003)

Bacterial

• Salmonella spp.

• Escherichia coli

• Chlamydophila spp. (see also Systemic Disorders)

Fungal

• Candidiasis

Protozoal

• Cryptosporidium serpentis

• Entamoeba invadens

• Eimeria

• Caryospora

• Isospora

• Flagellates e.g., Trichomonas.

Parasitic

• Ascarids

• Ophiascaris

• Polydelphis

• Hexametra

• Ophiostrongylus

• Hookworms

• Kalicephalus

• Capillaria

• Strongyloides

• Oxyurids

• Tapeworms

• Flukes

• Pentastomids (especially Armillifer armillifer, Porocephalus spp., Kiricephalus spp.—see also Skin Disorders)

Neoplasia

• Adenocarcinomas

Other noninfectious problems

• Foreign body ingestion or impaction

• Constipation

• Dystocia (as a cause of constipation)

• Cloacal prolapse

• Cloacitis

• Cloacoliths

• Intestinal foreign body

• Intussusception

• Extraintestinal mass (e.g., renal neoplasm)

• Dystocia

Snakes..........................................................................................................

Fig 11-7. Common gastrointestinal parasites of snakes (not drawn to scale).

• Hypocalcemia/metabolic bone disease (see Nutritional Disorders)

• Parasitism

Findings on clinical examination

• Vomiting/regurgitation

• Weight loss

• Lethargy

• Chronic regurgitation, extreme weight loss, depression, mucus-laden stools, and an obvious abdominal bulge caused by hypertrophy of the gastric mucosa (cryptosporidiosis)

• Dysentery (mucus-laden, bile stained, and/or showing frank blood), anorexia, dehydration, wasting, and death (Entamoeba invadens)

• A coelomic mass may be palpable.

• Petechial skin hemorrhages (Kalicephalus—see Skin Disorders)

• Cloacal prolapse (differentiate from prolapse of the colon or hemipenes)

Investigations

1. Microscopy

a. Fresh fecal sample—“wet prep” (Fig. 11-7 and Table 11-4)

2. Radiography

a. Plain radiographs

b. Contrast studies (e.g., for hypertrophic gastritis—cryptosporidiosis)

Contrast studies in snakes

1. Barium sulfate suspension given by gavage at 5 mL/kg

2. Double contrast: Immediately follow barium with 45 mL/kg air

3. Take first radiograph after 15 minutes.

3. Routine hematology and biochemistry

4. Culture and sensitivity

5. Endoscopy

6. Biopsy/necropsy

7. Electromicroscopy

a. Reovirus

8. Ultrasonography

Management

• For fluid therapy and general management, see Nursing Care.

TreatmentZspecific therapy

• Reovirus

• Supportive treatment only

• Salmonellosis

• Probably best considered as a normal constituent of the snake cloacal/gut microflora

• Occasionally pathogenic to snakes. May cause erosive gut lesions with subsequent bacteremia/septicemia

• Excretion likely to increase during times of stress (e.g., movement, illness)

• Treatment usually not appropriate as unlikely to be effective long term and may encourage resistance

• Recommendations for prevention of salmonellosis from captive reptiles issued by the Centers for Disease Control and Prevention in the United States include:

- Pregnant women, children to generate a ketoacidosis

• Supplement with vitamin E to reduce the risk of steatitis.

• Steatitis

• Secondary to a diet high in saturated fats (e.g., obese rodents)

• Treat with vitamin E at 50 mg/kg PO or IM.

• Offer a diet low in saturated fats.

Hepatic disorders

Viral

• Adenovirus (Boidae)

• Reovirus (king snakes—Reavil et al 2003)

Bacterial

• Mycobacteriosis (granulomas—may be multifocal)

Fungal

Protozoal

• Entamoeba invadens (see Gastrointestinal Tract Disorders)

Parasitic

• Capillaria spp. (especially earthworm-fed garter and water snakes)

Nutritional

• Hepatic lipidosis

Neoplasia

• Hepatocellular adenoma (garter snake, Thamnophis radix)

• Secondaries from other tumors

Other noninfectious problems

• Biliary cysts

Findings on clinical examination

• Loose feces (see also Gastrointestinal Tract Disorders)

• Large swelling midbody (hepatomegaly, biliary cysts)

• Neurologic signs (hepatic encephalopathy—see Neurologic Disorders)

• Jaundice (icterus)

Investigations

1. Fecal examination

a. Capillaria eggs: Typical urn shape with operculae at either end (see “Investigations” in Gastrointestinal Tract Disorders)

2. Radiography

a. Hepatomegaly

b. Hepatic masses

3. Routine hematology and biochemistry

4. Culture and sensitivity

5. Endoscopy

6. Biopsy/necropsy

a. Adenoviral inclusions

b. Ziehl-Neelsen staining and PCR for mycobacteria

7. Electromicroscopy

8. Ultrasonography

Management

• Milk thistle (Silybum marianum) is hepatoprotectant. Dose at 4 to 15 mg/kg PO b.i.d. or t.i.d.

• For ascites try furosemide at 2 to 5 mg/kg PO, SC s.i.d. if ascitic.

TreatmentZspecific therapy

• Mycobacteriosis—see Systemic Disorders

• Capillaria

• Fenbendazole at 25 mg/kg PO every 2 weeks for 3 treatments

• Biliary cysts

• Removal of fluid percutaneously

• Surgical resection

• Hepatic lipidosis

• Fluid therapy and nutritional support

• Covering antibiotics

• Lactulose 0.05 mL/100 g PO s.i.d.

Pancreatic disorders

Viral

• Paramyxovirus

Investigations

1. Radiography

2. Routine hematology and biochemistry

3. Culture and sensitivity

4. PCR and HI testing for paramyxovirus

5. Endoscopy

6. Biopsy/necropsy

a. Pancreatic ductular lesions (paramyxovirus)

7. Ultrasonography

TreatmentZspecific therapy

• Paramyxovirus: No specific treatment

Cardiovascular and hematologic disorders

Bacterial

• Vegetative endocarditis

• Granulomatous pericarditis

Protozoal

• Haemogregarina spp.

• Hepatozoon spp.

Parasitic

• Filarial worms (Oswaldofilaria, Foleyella, Macdonaldius spp.—see also Skin Disorders)

Nutritional

• Visceral gout (uric acid in pericardial sac—see Renal Disorders)

• Neoplasia

• Leukemia

Other noninfectious problems

• Anemia

• Cardiomyopathy

• Myocardial mineralization

• Thromboembolism

• Myocardial ischemia

• Congestive heart failure

• Developmental abnormalities

Findings on clinical examination

• Lethargy

• Apparent respiratory disease (see also Respiratory Tract Disorders)

• Pale mucous membranes

• Edema

• Cardiomegaly—may be visible externally as a mass around 22% to 35% of the snout­vent length. It may be seen to be beating (differentiating the heart from pericardiac masses, such as granulomas). Note: Very thin, anorexic snakes may appear to have a large heart secondary to loss of surrounding tissue.

• Avascular necrosis of the tail tip (thromboembolism)

^A

Investigations

1. Radiography

a. Cardiomegaly

b. Calcification of blood vessels

2. Ultrasonography and Doppler blood-flow detectors

a. Cardiomyopathy

b. Pericardial effusions

c. Vegetative endocarditis

3. Electrocardiogram

a. Valentinuzzi et al (1969b) suggest that an ECG can be taken with two leads:

i. A longitudinal lead that consists of a rostral electrode located at 10% of the body length and a caudal electrode at 50% of the body length; both electrodes are on the ventral surface of the animal.

ii. Two transverse electrodes are located bilaterally at the level of the heart (approximately 24% of the body length).

iii. Changes in the position of the heart, either during handling or by artificial respiration, may cause significant changes in the magnitude and orientation of the vectors. During recording of the transverse leads, rotation around the YY axis usually produces large variations in the amplitudes of the ECG waves. Spontaneous changes in T amplitude are relatively common.

b. ECG of the boa constrictor at rest and at room temperature (Table 11-5)

i. The ventricular T wave is generally in the same direction as the major deflection R; Q and S are poorly developed. The T wave also varies greatly in amplitude and may become completely inverted without apparent change in the position of the leads relative to the heart.

ii. There is an SV complex preceding the P wave.

iii. Valentinuzzi et al (1969a) found experimentally that as the heart deteriorates and dies, the relative and absolute amplitude of the SV complex markedly increases.

4. Routine hematology and biochemistry

a. Anemia

b. May be artifactual due to lymph contamination and dilution

5. Cytology: May find filarial worms on blood smear

6. Culture and sensitivity

7. Endoscopy

8. Biopsy/necropsy

Management

• Provide high-oxygen environment.

TreatmentZspecific therapy

• Hemoparasites

• Loading dose of chloroquine phosphate (5 mg/kg PO) and primaquine phosphate (0.5 mg/kg PO)

• Continue with chloroquine at 2.5 mg/kg PO once weekly and primaquine at

0.5 mg/kg PO once weekly for 12 to 16 weeks.

• Filarial nematodes (see Skin Disorders)

• Thromboembolism

• No established treatment. Possibly try NSAIDs

• Necrotic extremities may require surgical amputation.

• Investigate underlying factors (e.g., septicemia, low temperatures)

• Cardiomyopathies

• Furosemide at 2 to 5 mg IM, IV, or PO s.i.d. or b.i.d.

• Leukemia

• Treatment potentially difficult and untried

• Radiation therapy has been used with lizards (see Chapter 10) with a single low-dose whole-body radiation treatment of 1 gray.

• Anemia

• The underlying cause should be investigated.

• Blood transfusion from a conspecific or possibly a close relative (same genus) could be attempted.

• Oxyglobin

Systemic disorders

Viral

Bacterial

• Septicemia/bacteremia

• Salmonella arizona

• Chlamydophila pneumoniae

• Chlamydophila spp. (Jacobson et al 2002)

• Mycobacteriosis

Fungal

• Cryptococcus neoformans

• Zygomycete fungi

Neoplasia

• Sarcoma (Abou-Madi et al 1994)

• Mesothelioma

• Lymphocytic leukemia (Raiti et al 2002)

• Multicentric T-cell lymphoma (Raiti et al 2002)

Other noninfectious problems

• Cardiac disease (see Cardiovascular and Hematologic Disorders)

• Gout (see Renal Disorders)

• Amyloidosis

Findings on clinical examination

• Anorexia

• Weight loss

• Lethargy

• Altered behavior (e.g., shunning normal basking areas, constantly hiding)

• Inappetence; petechial hemorrhages visible in the skin, especially the ventral scales; may show CNS signs such as incoordination, frantic movements, or loss of the righting reflex (septicemia)

• Swellings (neoplasia)

• Clinical signs may vary with organ system affected.

Investigations

1. Radiography

2. Routine hematology and biochemistry

a. High actual or relative heterophila (inflammatory)

b. Multiple abnormal leukocytes (leukemia)

3. Culture and sensitivity

a. Blood culture (septicemia/bacteremia)

4. Serology for Cryptococcus

5. Cytology

a. Ziehl-Neelsen staining and PCR for mycobacteria

b. Immunohistochemistry and PCR for Chlamydophila and Chlamydia-like organisms (Soldati et al 2004)

c. Tracheal washings or cerebrospinal tap to isolate Cryptococcus

6. Endoscopy

7. Biopsy/necropsy

a. Single or multiple granulomas (mycobacteria, fungi, Chlamydophila pneumoniae, Chlamydia-like organisms)

8. Ultrasonography

Management

• Fluid therapy—see Nursing Care.

TreatmentZspecific therapy

• Septicemia

• Supportive treatment

• Antibiotics

• Mycobacteriosis

• Potential zoonosis. Consider euthanasia.

• No successful treatment for mycobacteriosis in reptiles reported

• Cryptococcosis

• Difficult to treat. Consider using:

- Ketoconazole at 10 to 30 mg/kg PO s.i.d.

- Topical ketoconazole cream

- Itraconazole 5 mg/kg PO every other day

• Lymphoma and leukemia

• Treatment potentially difficult and untried, but see Chapter 10

• Sarcoma—see Musculoskeletal Disorders

Musculoskeletal disorders

Bacterial

• Osteomyelitis

• Abscessation

Fungal

• Granulomata

Protozoal

Parasitic

• Cestodes: Diphyllobothrium and Spirometra (sparganosis)

Nutritional

• Prolonged anorexia

Neoplasia

• Sarcoma

• Spinal neoplasia

• Fibrosarcoma

• Osteosarcoma

Other noninfectious problems

• Traumatic fractures

• Spondylitis/spondylosis

• Myopathies

• Congenital abnormalities

• Steatitis

• Fecal impaction—see Gastrointestinal Tract Disorders

• Congenital deformities due to incorrect incubation temperatures; drug administration while gravid; inbreeding

• Osseous dysplasia (inheritable)

• Muscle wastage secondary to chronic anorexia (see Anorexia)

Findings on clinical examination

• Severe kinking of the spine (myopathies, spondylitis/spondylosis, fractures)

• Obvious abnormalities, especially of the skull

--

• Swellings and/or erosions (neoplasia, osteomyelitis, abscessation, osseous dysplasia)

• Extreme muscle wastage

Investigations

1. Radiography

a. Approximate body organ position in snakes based on percentage of snout to vent (cloaca) length as measured from the rostral nares (Table 11-6). Note: This measurement does not include the tail.

b. Fractured ribs are a common finding (Hernandez-Divers & Hernandez-Divers 2001) that usually require no treatment.

c. Steatitis may be indicated by enlargement and greater density of the fat body.

d. Spondylosis/spondylitis, osseous dysplasia

2. Routine hematology and biochemistry

3. Culture and sensitivity

4. Endoscopy

5. Biopsy/necropsy

6. Ultrasonography

TreatmentZspecific therapy

• Diphyllobothrium and Spirometra (sparganosis)

• Surgical removal where feasible

• Praziquantel at 5 mg/kg PO, SC, or IM. Repeat after 2 weeks.

• Only feed prey prefrozen for at least 30 days.

• Complex life cycles

• Sarcoma

• Attempt surgical resection.

• Chemotherapy has been attempted (Rosenthal 1994) after surgical reduction.

• Doxorubicin at 1 mg/kg IV every 7 days for 2 weeks, then once every 2 weeks, then once every 2 weeks for a total of 6 doses of doxorubicin

• Intravenous access was maintained using a vascular port with the catheter tip into the right atrium.

Fig 11-8. A large Burmese python with a severe discharging abscessation of the spinal column. Radiography revealed osteolysis of the underlying vertebrae and a complete loss of continuity of the spinal column and spinal cord. This snake was paralyzed caudal to the lesion.

• Other neoplasia

• Attempt surgical resection.

• Cryosurgery

• Spondylitis/spondylosis

• Some cases may represent a Paget syndrome-like disease.

• Many cases actually have a spinal infection triggering osteolysis (Fig. 11-8), exostoses, and bony fusion of the vertebrae.

• Consider use of antibiosis and NSAIDs (e.g., meloxicam at 50 pg/kg PO or IM s.i.d.).

• Those constricting snakes with extensive fusion of the spine may be unable to prehend and feed properly and so should be considered for euthanasia.

• Osseous dysplasia

• Inherited condition. No treatment. Avoid use of parents carrying this disorder in breeding programs.

• Myopathies

• Guarded prognosis

• Attempt treatment with vitamin E and selenium supplementation.

Neurologic disorders

Viral

• IBD (arenavirus—Stenglein et al 2012)

• Paramyxovirus

• Reovirus

• Lentivirus

Bacterial

• Septicemia

• CNS granuloma

• Encephalitis

Fungal

• CNS granuloma

• Cryptococcus neoformans (see also Systemic Disorders and Respiratory Tract Disorders)

Protozoal

• Acanthamoeba

• Toxoplasma

Nutritional

• Thiamine deficiency (especially fish-eating snakes such as garter snakes—Thamnophis ^sPP∙)

• Biotin deficiency

• Hypoglycemia

Neoplasia

• Schwannoma

Other noninfectious problems

• Organophosphate toxicity (e.g., insecticidal aerosols and diffusers)

• Gout (see Renal Disorders)

• Liver disease (hepatic encephalopathy)

• Metabolic disease

• Trauma

• Ivermectin overdose

• Cedar shavings

• Spider gene in ball pythons P. regius

Findings on clinical examination

• Slight to marked head tremor

• Muscle tremors

• Loss of righting reflex

• “Star gazing” (Fig. 11-9)

• Aberrant behavior

• CNS signs and/or regurgitation in pythons and boas (IBD)

Investigations

1. Radiography

2. Routine hematology and biochemistry

3. PCR (esophageal swab and blood for IBD)

4. Cytology

a. Intracytoplasmic inclusion bodies (IBD)

b. Raised liver enzymes (hepatic encephalopathy)

Fig 11-9. A boa constrictor snowing classic star-gazing behavior.

5. Culture and sensitivity

a. Blood culture (septicemia)

6. Endoscopy

7. Biopsy

a. Liver, lung, esophageal tonsil, and other organs (IBD)

8. Ultrasonography

TreatmentZspecific therapy

• Septicemia

• Antibiotics

• Fluid therapy (see Nursing Care)

• Thiamine (vitamin B₁) deficiency

• Due to feeding fresh fish rich in thiaminase (e.g., whitebait)

• Treatment is with B₁ supplementation, and deficiency is avoided by providing a dietary vitamin B₁ supplement plus boiling of fish before feeding to denature the thiaminase.

• Biotin deficiency

• Seen in egg-eating snakes

• Supplement with biotin.

• Treat symptomatically.

• Acanthamoeba and Toxoplasma

• Treatment difficult

• Metronidazole at 100 to 275 mg/kg PO once only (only 40 mg/kg for king snakes and indigo snakes)

• Trimethoprim-sulfadiazine at 15 mg/kg PO daily

• Potential zoonoses

• Organophosphate toxicity

• Atropine at 0.04 mg/kg IM

• Supportive treatment

• IBD

• No effective treatment

• Supportive therapy

• Spider gene in ball pythons

• Alters the patterning into a weblike mesh along the body but can give rise to a range of pattern changes

• Dominant gene

• Clinical signs can vary from mild head tremor to star gazing and loss of equilibrium.

• No treatment. The continued breeding of such affected snakes may represent a significant welfare problem.

Ophthalmic disorders

The cornea is protected by a transparent spectacle made from fusion of the upper and lower eyelids. Snakes have rods and cones but lack a fovea; some snakes possess a conus papillaris (analogous to avian pecten).

Snakes have well-developed harderian glands; their secretions lubricate the subspectacular space. A second duct drains this space into the vomeronasal organ.

Examination of the posterior segment of the eye is difficult as the iris muscle fibers are striated and partly under voluntary control and so parasympatholytics (e.g., atropine) and sympathomimetics (e.g., phenylephrine) will not work. In addition the cornea is protected by the spectacle, which prevents absorption of topical nonparasympatholytic mydriatics (such as vecuronium). Consider ophthalmic examination either by using low light levels or GA.

Bacterial

• Subspectacular abscess

• Keratitis

• Panophthalmitis

Fungal

• Subspectacular abscess

• Keratitis

• Panophthalmitis

Neoplasia

Other noninfectious problems

• Trauma

• Retained spectacle

• Avulsion of the spectacle (usually iatrogenic)

• Occlusion of nasolacrimal duct

• Congenital absence of nasolacrimal duct

• Stenosis due to or following inflammation

• Congenital abnormalities

• Cyclopia

• Microphthalmia—often associated with head abnormalities

• Anophthalmia

• Exposure to excessive low temperature during hibernation (cataracts)

• Lenticular cataract

Fig 11-10. Retained spectacle in a young royal python.

Findings on clinical examination

• Permanent opacity of the spectacle due to one or more retained spectacles (Fig. 11-10). Associated retained skin may be visible on the head.

• Space beneath spectacle distended with clear fluid (occlusion of nasolacrimal duct)

• Subspectacular abscess

• The eye appears opaque and the spectacle may be bulge due to increased pressure in the corneospectacular space. This condition may be unilateral or bilateral. This condition can be associated with retained spectacle (dysecdysis—see Skin Disorders) or stomatitis (subspectacular abscess—see also Gastrointestinal Tract Disorders).

• Hypopyon

• Uveitis

• Cataracts

• Retinal degeneration

• Panophthalmitis

Investigations

1. Ophthalmic examination

a. Assess whether eye is able to rotate beneath the spectacle during rotation of the head (i.e., that there are no corneospectacular adhesions).

b. Space beneath spectacle distended with clear fluid (occlusion of nasolacrimal duct)

c. Subspectacular abscess: The eye appears opaque and the spectacle may bulge due to increased pressure in the corneospectacular space. This condition may be unilateral or bilateral.

2. Radiography

3. Routine hematology and biochemistry

4. Culture and sensitivity

5. Biopsy/necropsy

6. Ultrasonography

TreatmentZspecific therapy

• Retained spectacle. This is often associated with:

• Low humidity

• Anorexia

• Dermatologic conditions, including snake mites (see Skin Disorders)

• If the spectacle over the cornea is retained, then gentle rubbing while applying slight pressure with a damp cotton bud should eventually cause some ruching of the spectacle and allow its removal.

• Do not pull with forceps as you risk avulsing the cornea with consequent loss of the use of that eye. If very adherent, the spectacle can be loosened by application of 10% acetylcysteine.

• Subspectacular abscess

• Treatment involves surgical incision into the spectacle to allow an assessment for any corneal lesions.

• All debris should be flushed from the corneal surface, and if possible the nasolacrimal duct can be cannulated and flushed.

• Topical ophthalmic antibiotic or antimycotic preparations should be used (see Skin Disorders).

• Attend to any underlying conditions (e.g., stomatitis).

• A new spectacle should form at the next skin shed. To prevent dessication, consider attempting to suture a contact lens in place.

• Nasolacrimal duct occlusion

• Treatment is similar to subspectacular abscess.

• Conjunctivoralostomy can be attempted in large snakes by passing a curved 18G needle from the inferior conjunctival fornix into the roof of the mouth such that it emerges between the palatine and maxillary teeth. A 0.025-inch Silastic tubing, threaded through the needle and secured at each end with sutures, may work in some cases.

• Avulsion of the spectacle

• Often the eye is so badly damaged that enucleation is required.

• Otherwise treat as for repair of subspectacular abscess.

• Congenital defects

• No treatment

• Consider incubation parameters (temperature, humidity, etc.) as well as genetic factors when considering cause.

Endocrine disorders

Little studied in reptiles

Neoplasia

• Thyroid neoplasia (especially garter snakes, Thamnophis spp.)

Other noninfectious problems

• Hyperthyroidism (see "Dysecdysis" in Skin Disorders)

Findings on clinical examination

• Swollen cervical region (thyroid neoplasia—Fig. 11-11)

• Excessive repetitive skin shedding

Fig 11-11. A garter snake with a cervical swelling; surgical resection revealed a thyroid carcinoma.

Investigations

1. Radiography

2. Routine hematology and biochemistry

a. Blood T₄ levels (Table 11-7)

3. Culture and sensitivity

4. Endoscopy

5. Biopsy

6. Ultrasonography

TreatmentZspecific therapy

• Thyroid neoplasia

• Surgical resection. Often metastasizes

• Hyperthyroidism (see Skin Disorders)

Renal disorders

Bacterial

• Bacterial kidney disease/abscessation

Fungal

• Mycetoma (e.g., Aspergillus spp.)

Parasitic

• Flukes (especially in king snakes, indigos, boas, tropical rat snakes, and bushmasters)

• Aberrant Strongyloides spp. infestation (Veazey et al 1994)

Neoplasia

• Renal adenocarcinoma (Gravendyck et al 1997)

• Renal cell carcinoma (may metastasize to lungs and liver)

Other noninfectious problems

• Gout

• Iatrogenic drug toxicity, especially nephrotoxic drugs, including the aminoglycosides

Findings on clinical examination

• Anorexia

• Lethargy

• Weight loss

• Polydipsia/polyuria

• Marked swelling of caudal third of coelom (renomegaly, renal neoplasia, extreme renal gout)

• Anuria

• Edema

• Pale mucous membranes

• Mortalities

Investigations

1. Radiography

a. Renomegaly

2. Routine hematology and biochemistry

a. No good single test. Snakes with renal disease may show hyperuricemia, hyperuremia, hyperphosphatemia, hyperkalemia, hyponatremia, and hyperproteinemia or hypoproteinemia.

3. Urinalysis

a. Renal casts

b. Inflammatory cells

4. Fecal examination (see Gastrointestinal Tract Disorders)

5. Culture and sensitivity

6. Endoscopy

a. Abnormalities in shape, color, or size of kidneys

b. Flukes in cloaca (and feces)

7. Biopsy/necropsy

a. Flukes in kidneys (also on postmortem); can cause an interstitial nephritis and other renal abnormalities

b. Ureteritis and nephritis caused by Strongyloides spp.

c. Mycetoma

8. Ultrasonography

a. Hyperechoic or hypoechoic, focal or multifocal changes; alteration of size

TreatmentZspecific therapy

• Flukes

• Praziquantel at 5 mg/kg PO, SC, or IM. Repeat after 2 weeks.

• Freeze food items (e.g., frogs, fish) for 3 days prior to feeding to eliminate intermediate stages.

• Aberrant Strongyloides infestation—see Gastrointestinal Tract Disorders

• Bacterial renal disease

• Antibiotics (beware nephrotoxic medications)

• Fluid therapy

• Mycetoma

• Poor prognosis. Attempt antifungal therapy (see Systemic Disorders) as well as general renal supportive therapy.

• Gout

• Fluid therapy

• Allopurinol at 10 mg/kg PO s.i.d. Note: This will only prevent subsequent uric acid deposition.

• Very guarded prognosis

• May be linked with renal disease, chronic dehydration, or use of nephrotoxic drugs

Reproductive disorders

Snakes can be either oviparous (egg-laying) or viviparous (live-bearing). Typical oviparous snakes include the colubrids and pythons. Typical viviparous snakes include the boas and garter snakes (Thamnophis spp.).

Noninfectious problems

• Dystocia

• Preovulatory ovarian stasis (POOS)

• Egg stasis (postovulatory)

• Ectopic pregnancy (viviparous species)

• Prolapsed hemipene

Findings on clinical examination

• Eggs often palpable in the caudal third of the coelom

• Straining

• Poor condition

• Obesity

• Dehydration

• Presence of some eggs or young

• One or two large, swollen often spikey structures hanging from the cloaca (prolapsed hemipenes)

Investigations

1. Radiography

a. Snake eggs are generally poorly calcified and so appear as rounded soft-tissue opacities in the caudal coelomic cavity.

b. Fetal skeletons may be visible in advanced gestation in live-bearing snakes (e.g., boas)

c. The hemipenes of some species are calcified and can be identified radiographically.

2. Routine hematology and biochemistry

3. Culture and sensitivity

4. Endoscopy

5. Biopsy

6. Ultrasonography

a. Useful for POOS and identifying young in live-bearing snakes

TreatmentZspecific therapy

• Dystocia

• Provision of correct environment, including appropriate temperature, humidity, and nesting chamber, may induce normal egg-laying or birth.

• Medical induction

- There is a small window of opportunity for the effective use of oxytocin; best used within 48 to 72 hours of obvious nesting or straining seen (Stahl 2000).

- Use oxytocin at 5 to 20 IU∕kg IM, starting at the lower dose; repeat 2 to 3 times at 6- to 12-hour intervals.

- Vasopressin at 0.01 to 1.0 μg∕kg IV, IM (more potent than oxytocin in reptiles)

- Digital manipulation. In some cases eggs can be manipulated out of the cloaca. This should be done under GA as it is a very delicate procedure and there is a significant risk of trauma.

• Percutaneous ovocentesis. Performed under anesthesia with sterile 20G needle. Beware of yolk leaking into coelomic cavity, aspiration of the viscera or their contents, both of which will trigger a serositis. Allow snake to pass collapsed eggs. If the eggs have been present for several days, then the yolk may be solid and resistant to aspiration.

• Salpingotomy; easier than above; may require multiple incisions to remove all eggs

• Ovariosalpingectomy. Make a paramedian incision along the junction between the ventral scales and the body wall to avoid incising into the ventral midline and the underlying ventral vena cava.

- Consider ovariosalpingectomy for nonbreeding females to prevent future problems.

• Ectopic pregnancy

• Surgery

• Prolapse of hemipene

• Attempt replacement (with lubrication) and pursestring suture around the cloaca.

• If severely swollen topical glycerin or concentrated sucrose solution may reduce the swelling enough to allow reduction.

• Badly damaged, infected, or paralyzed hemipenes should be resected. Providing the snake still has one functional hemipene, it can still breed.

Neonatal disorders

Noninfectious problems

• Prolapse of the umbilicus

• Congenital deformities

• Dead in shell (mid to late embryonic deaths)

Findings on clinical examination

• Bulging of tissue at the umbilicus of newborn or newly hatched snakes. Bulge may contain coelomic lining, yolk sac remnant, and coelomic fat.

Investigations

1. Radiography

2. Routine hematology and biochemistry

3. Culture and sensitivity

4. Endoscopy

5. Biopsy/necropsy

6. Ultrasonography

TreatmentZspecific therapy

• Prolapsed umbilicus

• Clean and replace prolapse. Suture in place.

• May require surgical resection of yolk sac remnant

• This is particularly prevalent in hatchlings with incomplete yolk sac resorption, where the yolk sac membranes adhere to dry surfaces or to the inside of the shell (especially if the humidity is too low). Keep hatchlings with pronounced egg sacs in moist, clean surroundings until resorption takes place. Do not attempt to separate the hatchling from the egg, but increase humidity and/or remove the hatchling plus egg to a warm, humid environment to allow natural separation.

• Dead in shell. Can be due to a variety of conditions. Consider:

• Nutritional status of parents, especially the female

• Incubation parameters (temperature, humidity, hygiene, oxygen levels, CO₂ levels)

• Bacterial and fungal infection

• Congenital abnormalities

• Hereditary conditions

• Incorrect incubation parameters