DEAR DR. FOX: My husband and I recently adopted a dog that had been rescued from a puppy mill. She has lived in a crate for the past six years and, therefore, it is normal for her to go to the bathroom in her crate. She has adapted very well to our household of two other dogs and two cats.

Fortunately, I work at home, so we have made good progress in housebreaking her. We take her outside after meals and periodically during the day and compliment her for relieving herself outdoors. When she's had accidents, we've chastised her without going overboard and then resumed the positive reinforcement when she gets it right.

Our issue is that she has not realized she can go outside by herself through the dog door anytime she wants. She easily uses the dog door and will go out on her own to sit or walk around outside. How can we help her understand that she can, and should, let herself out to go to$the bathroom without waiting for us to lead her outside?

-- K.W., Silver Spring, Md.

DEAR K.W.: I applaud the fact that you adopted a dog from a puppy mill. She was treated abominably. Six years in a crate! The inhumanity that so many people are capable of makes me ashamed to be a member of the same species.

Your poor dog may, with time, learn not to soil in the house. No fussing or disciplining. Quietly clean up and ignore. Let her outside through the dog door and lead her to the urine-soaked rag or paper towels that you put on the ground after cleaning up. This way, she will eventually make the connection through associative learning.

She does seem to need to urinate a lot so -- to be on the safe side -- have her kidney function checked and get a urine sample tested for lower urinary-tract problems that she could have developed from the stress of living under the deplorable conditions at commercial puppy-mill prison camps.

DEAR DR. FOX: I nearly lost my 21-year-old Siamese cat Kiwi last year to what I am almost certain was pet-food poisoning.

He had always been very slender but after this illness, he has been a virtual walking skeleton (although he did have good appetite and drank sufficient water). He went into severe decline two weeks ago since we lost our other elderly cat to cancer.

He was backing away from eating and was obviously confused and depressed. One evening, I was cooking tilapia for dinner, and he came into the kitchen crying for some. I immediately served him my fillet, and he ate it ravenously. Since then, I keep my freezer stocked with fish fillets that I poach for him daily. I still make an assortment of other cat foods available for him, but he usually just barely nibbles at them before he goes to the kitchen for his fish fillet. I have been adding one teaspoon of salmon oil to the fish, and he hasn't looked this bright and healthy since he became sick last year.

Am I harming him by giving more salmon oil than you recommend? Is there harm in his ingesting fish every day? If daily fish is OK, should I be giving him an assortment rather than just tilapia? Is there something else I should try adding to his diet to ensure adequate nutrition, keeping in mind that he refuses to eat any other meats I give him? Would a poached egg be good or bad for him? -- S.S., Round Hill, Va.

DEAR S.S.: Many cats (and dogs, too) are certainly suffering from the aftereffects of having their kidneys severely damaged by adulterated pet food in the March 2007 recall/debacle. Given your cat's age and poor appetite, you are at the stage where it's best to give him whatever he will eat.

Cats in generally poor condition with a variety of health problems have shown a dramatic turnaround after receiving various dietary supplements, including fish oil. I would not give more than a 1/2 teaspoon of fish oil daily, broken up into, say, five to six small doses in five to six small meals a day. Salmon oil from farmed salmon is probably loaded with toxic dioxins -- Atlantic cod-liver oil is superior. Try him on other protein sources like lightly cooked egg, turkey, rabbit, chicken hearts and calves liver. Some cats are allergic to fish, which I believe is due to the fact that fish were never part of their normal desert diets.

Send your questions to Dr. Fox in care of this newspaper. The volume of mail received prohibits personal replies, but questions and comments of general interest will be discussed in future columns.