Smaller focus — don't get to compare dog's problems or progress with other dogs in class or other people's questions, etc.. (atyourservicedogtraining.com)
Training a single dog and a group of dogs in a class requires different skill sets. (platpets.com)
Previously, the slow kill method of heartworm treatment was deemed acceptable for dogs in the class I (early) stage of heart disease but this has changed given confirmation of resistant strains. (vin.com)