Dogs do not use mask when going for a walk nor they observe the security distance. On the contrary, they frequently join their noses, and put their noses where other dogs had put them before or had urinated. So, as they are our pets, it is important to know if they can be asymptomatic transmiters of sars-cov-2. Do we know it? At least, have we tested asymtomatic pets of people infected with sars-cov-2?
It may be too early to tell.
Testing of dogs in Wuhan found no infected dogs "487 dogs including 90 beagle dogs, 147 pet dogs and 250 street dogs during the outbreak of SARS‐CoV‐2 were also tested serological negative." from https://onlinelibrary.wiley.com/doi/full/10.1111/tbed.13577
This article mentions deliberate infection of five dogs. on this very small sample they suggest that dogs are not likely to become carriers.
"Coronavirus can infect cats - dogs, not so much." https://www.nature.com/articles/d41586-020-00984-8
found by searching "dog" on LitCovid at https://www.ncbi.nlm.nih.gov/research/coronavirus/