How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Jane Lefler Your Own Question
Jane Lefler
Jane Lefler, Animal Behaviorist
Category: Dog Training
Satisfied Customers: 20181
Experience:  Dog breeder/Trainer and Behaviorist 18+ years
Type Your Dog Training Question Here...
Jane Lefler is online now

We are currently fostering a dog from the animal rescue and

This answer was rated:

We are currently fostering a dog from the animal rescue and he is a great dog in the house. When we take him out he goes mental if he sees any other dogs, on or off their leads. He lunges and looks so vicious and angry and barks in a nasty way. He isn't a nasty dog in any way and we are desperate to help him. We are both retired and have time for him and we show affection. We don't know his background. What should we do ??
Hi Jacustomer,
My name is Jane. I have been working professionally with animals especially dogs in both health and behavioral issues for over 18 years. I have over 14,000 satisfied customers. It will be my pleasure to work with you today.
In order to supply you with the best information, I do need to ask for some additional information. Once I receive your answer, it will likely take me about 30-45 minutes to type up your response. I hope you can be patient.
How long have you had him?
Does he seem to know obedience commands?
Are you working with him on obedience training?
Do you know if he has any medical problems?
What medical tests have been run on him?
Customer: replied 3 years ago.

Hi Jane. We have had Chas for only two weeks. He is intelligent and understands commands,Sit and Come here. He will give paw on request.

We are trying to gently train him when he is out with us on walks, trying to focus him more on us than on his obsession with looking round for other dogs.When he sees another dog his hackles go up and there is no distracting him from lungeing and barking quite ferociously. He bites at his back end, it looks irritated and hair loss. The Animal Concern said he had been brought in with lots of fleas in that area and they had treated him, now he has no fleas. He also has fatty lump on left side of his neck

which has been checked out by vet who said it was harmless and is not bothering him or needs treatment...Hope you can help. Thankyou. Christine.

thanks for the additional information. It is helpful.
Dogs are aggressive toward other dogs for a variety of reasons. It might be that they are fearful of other dogs and thus are aggressive before the other dog can be. In other cases, a dog is aggressive in order to dominate the other dogs and be the alpha member of the pack. Other causes could be that the dog feels they are the alpha member of the pack and as the alpha member they must protect the pack (you) from threats (other dogs). If a dog sees you as the boss, they will expect you to protect them. At this point, he likely doesn't trust people to do this for him yet.
Sometimes owners make the situation even worse by tensing up and worrying about what will happen. The dog senses the owner worry and feels that he is justified in his aggressive stance because you are obviously worried about the dog. They don't know you are worried about them attacking, they just feel that you are worried and assume it is the other dog. You need to try and remain as calm as possible.
For a dog like this, total control is necessary. This means not only physical control but on a mental level, you must be the boss. To accomplish this, you may want to have the dog wear a basket muzzle anytime he is not in your own house or yard. This will not only prevent bites but also allow you to feel more at ease when walking him. If he is not neutered, have that done.
Many dominant dogs are described as well behaved until you try to get them to do something they do not want to do, and then they reprimand you either with a growl or bite if you don't heed the growl. Things like taking away something they want, making them move when they don't want to, waking them up, etc can cause them to reprimand (bite) you. You have only had him a couple of weeks, so watch for this behavior as he becomes used to his new home.
You will need to have him obedience trained. If you can, I would do group classes (with the muzzle if necessary) and let the trainer know of the problem your dog has. It might take you a few months of basic training before he is ready for group class.
The following site is helpful for teaching you how to train your dog. Be sure and click on the link to the page on obedience at the bottom. and links on subsequent pages leading to detailed instructions.
Training works best if you train at least 30 minutes a day (two 15 minute sessions). I would start making your dog work via the Nothing in life is free program (NILF). It is outlined below.
Obedience training serves various purposes. It helps a dog learn what humans expect of them when they state a command which leads to self confidence and less fear. Each time a dog obeys a command, even if it is for a treat, it makes them a little more submissive to that human in the future which helps with aggression. And since it is the leader or boss who is responsible for protecting the pack, if the dog is made submissive with training, you are responsible for protecting him, so that can reduce aggression due to fear and dominance.
I think you will be pleasantly surprised at how well he does with training. Dogs like knowing what is expected of them and they love the little paper thin slices of hotdogs that I use for treats while training. Give this a try and see how it works for you.
Keeping a hot dog sliver in your hand on walks helps keep his attention on you. Start with this trick in the yard and feed him the pieces as long as his attention is on you and your hand. Gradually increase the time he has to be paying attention to get the treat. the idea is that if he is concentrating on you, he won't have time to fixate on the other dog.
It will be helpful if you can find someone with a dog to help you once you have your dog listening to commands consistently. What you will do is have your dog on the leash. You will have your helper off in the distance. Your helper will gradually move their dog a bit closer to you preferably walking past your position in the distance. As long as your dog ignores them, you can give your dog praise and a treat. The second you see him fixate on the other dog or show any other sign of aggression (hair standing up, etc.) give your dog a correction by giving a short tug and a firm low toned "NO". It shouldn't take your dog long to realize you will not tolerate the aggression and that if he ignores the other dog, he gets treats. Once this happens you can repeat the training moving the other dog closer until he is no longer trying to lunge at other dogs. You will need to practice this when you and your dog are walking as well.
Another method gaining popularity can be found on this site:
In addition, if the situation is not improving using the techniques on the previous website, you may have to consult a professional behaviorist. You can usually find a behaviorist by asking your Vet for a recommendation or you may be able to find one using the following site.
I hope this information is helpful to you and you are satisfied with my response. If you would like any additional information or have more questions please don’t hesitate to press the reply to expert or continue conversation button so I can address any issues you still have .
Customer: replied 3 years ago.

Hi again. Thanks for the reply...will try what you have advised.

If we do manage to become his "pack leader" and he is rehomed permanently will he go back to his old ways with new people ??

If the new owners do not follow through with training and keeping the dog obedient, then it is possible that he will slip back into being aggressive toward dogs he doesn't know. However, you can recommend they continue working with him and provide them with the links. He'll be a better dog with ongoing training.
Jane Lefler and other Dog Training Specialists are ready to help you