I got certified 6 months ago. They still (in the US) recommend 2 breaths every 30 compressions. For 2 people, one person manages the AED, and the other does CPR and you switch every 2 cycles, or whenever one person is too tired to continue.

Point is moot, you probably don’t have enough mass, or lung volume to compress the chest and inflate the lungs on a giraffe.