1) An intra-oral examination can be performed using a mouth gag, tongue depressor/pen/pencil to encourage the reptile to open its mouth. A metal, hard plastic or wooden gag should never be used on a reptile. If they bite on this, it can cause damage to the jaw or teeth, especially if they have infection or metabolic bone disease. Care should be taken with chelonia as they have powerful jaws. It should be possible to perform a close examination of the tongue, the roof of the mouth and the nasal passages. There is no hard palate in reptiles, other than crocodylia. The glottis may also be visualised at the base of the tongue. Abnormalities such as a discharge from the nasal passages; petechiae or haemorrhages in the mouth; an abnormal or foul odour and evidence of white or yellow plaques on the mucosa should all be noted. Samples should be obtained for cytology and culture using a swab dampened with sterile water. It should be noted that many lizards have a two-coloured tongue e.g. the green iguana has a bright red tongue tip and a pale pink body to the fleshy tongue.
2) A detailed examination of the nares, ears and eyes will allow an assessment for upper respiratory tract disease. Clinical signs include: abnormal shaped nares; sinking of the globe of the eye; swelling below the globe of the eye (the region of the infra-orbital sinus); clouding of the cornea (an indication of impending shedding); discharge from the eye; swelling of the conjunctiva and corneal blemishes. Swollen, weeping or painful eyes, are often an indication of a retained shed (spectacle)- a common finding in snakes and lizards. The ear canal is located caudal and ventral to the lateral aspect of the eye. Ascending infection via the eustachian tube commonly results in abscessation. This is seen as distension of the skin overlying the ear canal. If present, this will require to be lanced, drained, cleaned and samples taken for culture and sensitivity.
3) A detailed examination of the skin/shell. This may show areas of retained slough: snakes should shed (ecdysis) their skin in one piece (including the eye-caps) about once per month; lizards shed in small patches and chelonia in small patches from the limbs and head/neck/tail. Dysecdysis (incomplete or improper shed) has many potential causes including disease, poor nutrition and/ or husbandry (Pollock, 2013). Geckos and small lizards often have retained shed on their toes, so these should be checked carefully- this will also allow any petechiae or ecchymoses to be observed, a possible indicator of septicaemia. These are often seen on the plastron (underneath shell of a tortoise). Abscesses appear as firm, inspissated subcutaneous masses.
4) A detailed auscultation of the lungs and air sacs. The lungs are best auscultated from the dorsum in chelonia and lizards. To improve sound conductivity, a damp towel/cloth may be placed over the reptile and the diaphragm of the stethoscope applied to this. Snakes are difficult to auscultate owing to their long thin lungs.
5) The heart is very difficult to auscultate and it is often preferable to use a Doppler probe to assess blood flow through/out of the heart to determine heart rate. It should be noted that the heart rate and heart sounds of reptiles are significantly different from mammals, owing to the different anatomy and physiology of the three-chambered heart (one ventricle and two atria). In addition, environmental temperatures will significantly alter heart rates.
6) A detailed examination of the limbs should be made. The long bones should be palpated as metabolic bone disease is common. Fibrous dystrophy, where the poorly ossified bone swells due to cartilage deposition, makes the limb look fat and muscular. Palpation reveals, however, that it is bone mass and not muscle. Shells of chelonia may be deformed and soft to touch. The mandibles of lizards may be bowed and malleable with this condition.
7) A detailed examination of the vent and caudal coelom should also be made. Many lizards have kidneys tucked into the pelvic area: so, these should not be palpable cranial to the wings of the ilia in normal animals. Snakes may be palpated, by running a finger along the ventrum, to feel for masses or obstructions. Chelonia are obviously difficult to palpate, although gentle palpation or ballottement of eggs or masses, by placing a finger cranial to a hind limb and rolling the animal onto its side and away again is possible. Snakes may be sexed by probing the cloaca in a caudal direction: a sulcus of 3-4 scales denotes a female, 6-7 scales length a male. Male lizards have hemipenes, bilateral grasping organs, used in copulation. Prolapse and infection is not uncommon. Cloacal prolapses are common in reptiles: a diagnostic work up of the cause of excessive straining is essential. Replacement and purse string suture is, however, not appropriate.