Unless your dog suffers from CCD – Canine Cognitive Disorder (similar to dementia or Alzheimer’s disease in humans), he/she is still capable of learning. It may take a little longer and require more repetitions, but with patience and understanding most dogs can learn what you are asking and how to comply. If you have adopted an adult dog, realize that your new friend may have to “unlearn” some old habits that do not conform to the new environment. These adult dogs are not being bad; they just haven’t been taught to do things the way you would like. The best way to remedy this is through positive training at any age not punishment.
Big or small, we train them all!