What follows is a post mortem examination on a Gopher snake. The snake was under veterinary treatment for a suspected liver tumour and was eating and very active until the time it was humanely euthanased. Appropriate protective clothing was worn and the snake was stitched afterward and disposed of in the correct manner. Permission was given by the owners for a post mortem to be carried out and used for educational purposes. The animal was well cared for by the owners and at all times (even after its death) was treated with kindness and respect. The images shown are for educational purposes only

Shown are images of the snake as presented for euthanasia. A clear swelling is visible in the middle portion towards the head. This area is occupied by the liver and the stomach. The snake had been under veterinary care and the lump had been present for roughly 8 months and had grown in that periodLiver function had been normal. the snake had been eating without regurgitating and had been acting normally in its enclosure. The snake was presented for euthanasia since although it was still bright, it had begun to regurgitate food. A liver mass was suspected but was not investigated due to the age of the snake and the fact it was acting normally.

a = palatine vein
b = opening to windpipe (glottis)
c = lingual (tongue sheath)

Note the ridge of cartilage over the glottis of this species, making placement of a breathing tube difficult

a = trachea (windpipe)
b = oesophagus (foodpipe)
c = jugular veins

The trachea is long in snakes which makes nebulisation slightly less effective at carrying medications to the lung when compared with tortoises. the jugular veins can have catheters placed for fluids but this requires anaesthesia

This image shows the heart (H) which is variable in position in the first third of the snake. most blood samples are taken directly from the heart, a procedure which is safe even in concious snakes

a = anterior vena cava, large blood vessel bringing blood back from the front portion of the snake to the heart
b = posterior vena cava, bringing blood back fron the main body to the heart
c = right lung: boids have a large right lung and a smaller functional left lung. Others such as this snake have a right lung only. the end of the lung forms an air sac (see later)
d = trachea (wind pipe) as it enters the lung
e = heart: snakes have a 3 chambered heart with complete separation of the atria (upper chambers) and 1 ventricle (lower chamber)
the 2 small white tubes visible in the heart fuse to form the aorta (main artery leading from the heart) = f

The inner lining of the lung (L) is shown. This is to show the primitive air exchange surface. The lungs of reptiles are very different from those of mammals which have an intricate pattern of gas exchange surfaces (the bronchial tree). Reptiles need only a simple corrugation of the lung surface. in cases of pneumonia, pus can stick to the lung wall. increasing humiditiy helps clearance of these secretions in snakes. The heart (H) is also shown, as is the front portion of the Liver (Li)

Now we come to this snakes particular issues. The organ shown is the liver and it is very abnormal. The most normal part is highlighted with an asterisk (*) and even this is not totally normal. Most of the liver archetecture has been replaced with firm nodular masses with cysts of various size attached (#) A large cyst is present in the front portion of the liver and was the cause of the visible swelling. Histopathology is pending but these masses are almost undoubtably tumours. the fact that this snake was acting normally highlights the amazing reserve in the liver such that it can almost be totally destroyed and yet the animal can carry on as normal. in fact you can survive with about 25% of your liver

A quick review to show the relative positions of the Heart (H) and the liver in relation to each other and along the length of the snake

The liver has been reflected to show the Oesophagus (food pipe) (Oe) and also the terminal portion of the lung (L)as it becomes an air sac(A). The air sac has been opened to show how the inner lining turns into a simple membrane with little or no blood supply