Prebiotics basically provide an energy source for the good probiotic bacteria (they feed the bacteria) - as well as providing a suitable intestinal environment (acid) that promotes the growth of probiotic bacteria.

 These prebiotics (Fructo-oligosaccharides and mannon-oligosaccharides = simple sugars.) not only provide the right environment for probiotic bacteria - but they can also help fight against bad (pathogenic) bacteria. Pathogenic bacteria like to attach themselves on to the intestinal wall (see below) - to prevent themselves being washed out of the gut.

However, they prefer to bind to the saccharides - so if they are present in the diet - the pathogenic bacteria attach to them - and not the intestine - and are swept out of the gut along with the food.

Prebiotics are added routinely to some commercial rabbit foods (not chinchilla pellets as yet).  Fructo-oligosaccharides are however, found in fruit, so maybe the odd small slice of apple will not go amiss.  They are also now added to some brands of powdered probiotic.

• By adding probiotics to the chins usual diet (or drinking water) - you are encouraging certain species of beneficial bacteria - which help to "push out" the more harmful species.
• Good bacteria (probiotics) produce enzymes which help the digestive ability of the animal (chinchillas are hind-gut fermenters - which rely on a bacterial balance in their caecum to help digest their food).
• Good bacteria also provide a barrier against invading pathogens (bad bacteria).
• Digestive upsets are very common during times of stress (i.e. weaning for instance) - and it is during these times where using probiotics may be of great benefit.
• Antibiotics kill all bacteria (good and bad) - and additional usage of probiotics will re-establish a micro-flora.
• Detrimental (bad) bacteria such as E. coli attach themselves to the intestine wall (on certain attachment sites) by the means of hair-like structures (called fimbriae). However, certain species of good bacteria block these attachment sites - so the pathogens cannot stick!!
• Bad bacteria produce enterotoxins - there is some evidence that good bacteria can neutralise these toxins (subject to further research).
• Lactobaccilli (a species of probiotic bacteria) produce lactic acid - which changes the PH of the gut to a level that is not so easily tolerated by harmful bacteria.
• Research has shown that lactobaccilli has helped to increase white blood cell counts in animals that are given probiotics. This may aid the development of the immune system.