When it comes to depression in dogs, some symptoms include drastic weight loss, reduced activity, loss of appetite, less social interaction, lethargy or more sleeping, excessive shedding, refusal of water or treats, and sudden and drastic behavior changes.
When it comes to OCD, signs of dog mental illness include repetitive or intensified behavior, excessive tail chasing, self-mutilation, and a decrease in playfulness.
All these symptoms have been linked to the various mental health disorders listed above. However, remember that there are many, maybe short-term, reasons for dog sadness or anxiety. Keep in mind that your veterinarian is the one who can accurately recognize signs of dog mental illness and give a diagnose. If you think your furry friend is suffering from a mental health disorder, make sure to consult your vet about their symptoms right away.