[Fiona55]

Probably a stupid question but I have just read on another topic that people put garlic & avc in drinkers.  What is avc and what does it do & what is purpose of putting in garlic.  cheers

[arugula]

AVC is probably ACV - apple cider vinegar. You could do a forum search on that as the topic crops up often.

[kegs]

There are no stupid questions Fiona. 

Here's some info for you from the FAQ page on Apple cider vinegar (it's the unrefined version with bits in that you can get from Equine suppliers not the sort you get from the supermarket) and you add it to their drinkers (but only the plastic drinkers not the aluminium ones).

http://www.eden-livestock.co.uk/apple_cider_vinegar_article.htm

and garlic is meant to be good for their digestion.