Dear Cathy,

I adopted a three-year-old cockapoo from a shelter. Within two days, I realized he could not hear and confirmed it with my veterinarian. The vet said there seemed to be a residual ear infection, which we treated. He also tested positive for Lyme disease.

I have only had him for a short period of time, but am quite attached. He has no interest, however, in the multitude of toys I bought for him. He seems to sleep all the time. Treats don’t seem to work on him either. I know I can’t take him off the leash, but I really want to train him to run and fetch a ball and play with toys. I’m afraid his constant lying around will make him heavy.  Another vet said he may be older; maybe five- to eight-years-old. There’s no thyroid problem. He can’t even jump into my car; I have to pick him up.  What is that about? Otherwise the sweetest dog ever and a keeper. Any thoughts?

– Linda, Montauk, New York

Dear Linda,

Your newly adopted pup may be mentally grieving for a past owner or suffering physically because the past owner wasn’t able to take care of him in several ways.

First, he has Lyme disease – something that can be prevented with monthly tick preventatives, and which he clearly wasn’t on. Dogs with Lyme disease can suffer from severe fatigue, stiffness, discomfort, and pain, all of which make dogs not want to do much of anything. These symptoms can last for up to five months after diagnosis and treatment.

Second, your dog had a residual ear infection, which could also make him lethargic and disinterested in play. Even though treating the ear infection helps, he won’t feel himself until he completely recovers from it and the Lyme disease.

You didn’t say whether the deafness from the ear infection was permanent, but you can train deaf dogs with hand signals or by using a small flashlight as a clicker. Wave him over to you. When he responds, click the flashlight on and off and give him a high-value treat, like a tiny piece of cheese. To get him to sit, put a treat in your hand, hold a few inches over his head, and then move your hand back over his body and towards his tail, so his nose must point up to follow it, which makes him automatically sit. Make sure he sees the flashlight click on and off before giving the treat.

While some dogs are less playful than others – and he could be older than you originally thought – a little time for healing and a little bonding through training should eventually improve his level of activity.

Cathy M. Rosenthal is a longtime animal advocate, author, columnist and pet expert who has more than 25 years in the animal welfare field. Send your pet questions, stories and tips to cathy@petpundit.com. Please include your name, city, and state. You can follow her @cathymrosenthal