reddobes

There are different liver enzymes that are measured - typically ALT and ALP in dogs. They can be elevated for different reasons. ALP can be slightly elevated in young growing animals (bone growth). ALT is more liver specific and degree of elevation does not correlate w/ what is going on in liver. You need to know what the normal range is for the lab that ran it.
If it is the ALT that is elevated, I would recommend rechecking in 2-4 wks to see where it's at. It may be nothing, but could also be an early warning sign for something more serious. In an asymptomatic dog, I wouldn't worry too much at this point. If it remains elevated, then it warrants further investigation/monitoring.

Yes, melbrod, those things are true in vet medicine as well. Many of the larger reference labs/universities use the same chemistry and hematology analyzers used in human hospitals. Each lab has to establish it's own normal ranges and validate it for a given species.