There is a family in Australia who trains their dogs in SAR for lost pets. They usually find between 10 and 35 lost pets every two weeks or so. I would guess it would be along the same lines as finding people.
Shasta GSD 5/5/10 CGC, ITD, TC
"Dax" Thor z vom Weberhaus BCAT CAX2 CGCA ETD HCT NCO-1 PKD-T RATI RATN RA TC TKA 3/18/2013
"Hades" Guilty vom Blutfeuer 10/26/2018
Zena GSD 6/1/03-2/16/2016
Riley GSD/BC 1/10/05-2/1/2013