Here's detailed information on liver shunt
Liver Shunt Research
A bile acid test is given to determine liver function. This test does NOT diagnosis liver shunt...it solely indicates how the liver is functioning. Blood is drawn from the dog's jugular vein. The levels are read...pre fasting and post fasting. It's generally considered best to be given around 6 months of age. The cost of testing in our area is about 85 dollars.
If you read liver shunt/mvd threads...the majority of these dogs are very small.
Btw, was this the shihzu you posted about last week or so?