Impaction – What’s The Real Story?
Of all the contentious issues we have to deal with on a daily basis, the one that causes the most disagreement is the issue of substrates. And that is down to one factor, a word that strikes fear into any reptile keeper’s heart – impaction.
So what is impaction? Basically, it’s when a substance forms a blockage in the intestines which prevents the normal passage of food and fluid through the gut. This blockage is more serious than just a bit of constipation – it can be fatal. The mass presses on nerves and blood vessels, causing pain and distress, until the animal goes into clinical shock and dies. It’s an awful way to end a life.
So what causes it? The short answer is anything that goes in through the mouth and, for whatever reason, can’t get out the other end. When the poor reptile (although it can occur in any animal – if it’s got a gut, it can get blocked) ends up in surgery, the vet opens the gut and finds a stinking lump of solid food and substrate the answer seems clear, doesn’t it? The reptile ate substrate, so it got blocked. Take away the substrate, job done, it was the sand what done it.
But as you might imagine, nothing is ever that simple. Failure of the gut to work properly – leading to impaction – can have many causes, including:
- Incorrect temperature (usually too cold)
- Mineral deficiency
- Neurological disorder
- Infection – bacterial, fungal, or viral
- Foreign object
So we need to look at WHY the animal ate that substrate, or perhaps more accurately why that blockage (which happens to be made up of quite a lot of substrate) formed in the first place. Just removing the substrate stops the ingestion but fails to address the original problem; substrate eating very rarely happens in isolation, but is a symptom of a more serious problem. Treating the symptom without addressing the underlying problem will only make things worse.
The commonest one that we see is mineral deficiency. When an animal’s body becomes deficient in the minerals it needs to function efficiently, it takes steps to correct that imbalance – you may have seen nature documentaries of parrots or elephants gathering to eat mud for the minerals it contains. It’s an extremely common behaviour in wild animals; mineral content gets low, eat mud, mineral content improves.
However, this process needs other things to work. The body has to be able to use that mud, which means it has to be functioning within certain parameters such as hydration level, UV exposure, and temperature. If any one of those things is lacking, the mud doesn’t get processed and just sits in the gut doing nothing. The animal’s brain is still registering a deficiency, so it stimulates the mud eating behaviour once again but unless the rest of the conditions are correct it still won’t work.
More mud. More bulk. And the body is getting weaker and weaker, the muscular contractions of the gut (that should be moving the indigestible material along to the exit) become less efficient, and finally everything just stalls. The bones may be becoming soft due to the deficient state, so the pelvis may collapse and form a physical blockage even as the hind legs stop working.
So how do we stop this becoming a problem? You may have seen the fire triangle, a diagram which shows the three things that fire needs in order to burn.