Without dispute chinchillas should be fed a simple diet of good-quality chinchilla pellets and hay as their staple diet - and that is pretty much it.

This may seem bland but we must not lose sight of the fact that the chinchillas wild cousins have adapted to live on relatively low-nutrient forage, and our own domestic chinchillas digestion is unchanged from their wild counterparts.

However, that said, I am now going to be slightly contradictory and go on to say that some breeders (especially American) also give their chinchillas what is known as a "herd-supplement".

This was once (and perhaps still is) considered to be a very out-dated approach to feeding chinchillas, as it hales back to the days before chinchilla pellets were manufactured and breeders had to make up their own food for the chinchillas. 

Pellets have to cater for chins in ALL lifestages - including pregnancy, lactating and growing, as well as non-breeding adults. Therefore the protein levels tend to set for the "average" chinchilla.

Currently there is no demand for a separate type of pellet for young and breeding chins - and another type for maintaining non-breeding adult chins.  This is where an additional supplement may come in useful. 

Supplements tend to be cereal-based (oats, wheat, barley etc) with added wheatgerm (high in vitamin E, folic acid, EFA's and proteins) and bran.  To this mix edible dried herbs can be added.  These are a good source of phyto-nutrients.  A tiny amount of golden linseed will provide essential fatty acids, but only a tiny amount is needed.  An addition of a balanced multivitamin and mineral supplement is recommended, as cereals tend to be high in phosphorus and low in calcium.

Rolled oats are the safest of all cereal grains to feed - being relatively high in (soluable) fibre and low in digestible energy - they are not normally associated with over-fermentation in the hind-gut - UNLESS there is some degree of gut-stasis involved anyway! Oat hulls or groats are not recommended though!!!

N.B.  Hay/forage should always be fed - in order to promote peristalsis and limit any possibility of gastric stasis.

 A supplement has several uses ...........

1. It helps to condition breeding, growing or unwell chinchillas.
2. It is relished by chinchillas and is regarded as a "treat" by them, this allows a breeder to quickly spot if one chinchilla is off its food, and can then investigate the cause.
3. If well balanced, it is a useful source of extra nutrients.
4. It can tempt the appetite if the chinchilla has been unwell.

However, it also has drawbacks ............

1. It may encourage obesity if fed excessively.
2. It is expensive to feed if you have large numbers of chinchillas.
3. It is an added and unnecessary chore for larger breeders.
4. Has a very short shelf life (especially wheatgerm).

The main limiting factor of most cereals is that they tend to be deficient in a couple of the essential amino acids, especially lysine.  They are also rather high in phosphorus with is often present as a phytate, which can bind to calcium molecules, preventing their absorption.  A diet that is too high in phosphorus is not recommended, and the ideal ratio of calcium to phosphorus should be around 2:1 respectively. 

The "Kline Diet" (a top-selling American chinchilla diet) was developed and endorsed by a chinchilla rancher called Alice Kline (now sadly deceased).  She swore by a diet of pellets, hay and a balanced cereal-based supplement, and her chinchillas thrived on it.  Nowadays, the Kline Diet is still advocated and recommended by Amercian pet-owners and breeders alike, but it is not currently available to the UK.

Even if a supplement is fed as an additional ration - it is still important to make sure that a chinchilla always eats all its staple diet (hay and pellets), and does not gorge itself on "extras".  So the quantity and frequency of supplemental feeding will need to be monitored and adjusted, if necessary.

It is also very wise not to feed the supplement in the same bowl or feed-hopper as the staple diet, as the chinchillas will throw out all their pellets in an effort to get to the supplement, which often leaves them with nothing left to eat.

Some breeders feed a "treat" mix a couple of times a week anyway, a supplement mix is just taking this principle a step forward - with the aim of providing extra nutrition to those chins that need it.

Although some breeders swear by feeding an additional ration, others feel that it is unnecessary at the least and even dangerous at the worst, due to a chinchillas delicate digestion, which is not suited to a continuous rich diet.

However, I believe that it is very much up to the individual owner or breeder if they feel that a supplement has enough significant benefits to be worthy of the extra effort, time and money to feed it.

I hope this has provided some "food for thought" - please excuse the pun!