Why does my dog suddenly freeze, stare, and attack other dogs?

I am very sorry to hear about Bandit. This is a scary situation if Bandit is truly giving no warning prior to his aggressive outbursts. There may be subtle changes in his behavior that are difficult to pick up on without having observed aggressive dogs in the past. Neutering may help decrease his aggression toward other dogs but truly with unpredictable aggression like this a consultation with a veterinary behaviorist is recommended. They can discuss Bandit with you in depth, examine him and observe him in different situations and come up with a training plan to help you manage him (or they may advise he not be around other dogs if they feel his behavior is too unpredictable). I would talk to Bandit's veterinarian to find out about veterinary behaviorists in your area.

I'm sorry to hear that you're having this problem! If this has been a fairly sudden behavior change for Elsa, the first thing I would suggest would be to have her examined by a vet to see if there may be a medial reason for the aggression - many illnesses including thyroid problems and neurologic issues can cause sudden mood swings and behavior changes like this, as well as anything that may be painful such as an injury of some kind, arthritis, etc. If your vet determines that Elsa is healthy, then I would strongly recommend making an appointment with a veterinary behaviorist as the next step. Aggression towards humans is a serious and complex behavior issue that needs to be handled by a professional who can work with your dog in person. The behaviorist will evaluate your dog and help you determine what is triggering the aggression, then put together a detailed training plan to work on the problem. You can search for a board-certified veterinary behaviorist in your area here: www.dacvb.org

It sounds like your dog has unprovoked dog aggression, and because there isn't a trigger known for it, it's very hard to find a cause behind it. It could be he simply doesn't like something about your other dogs, and that makes him want to attack them. You have a couple of choices in this situation, one of which you probably will not like to hear. You can rehome to someone who doesn't have any other dogs. He will continue to attack your other dogs without provocation, and will likely end up seriously injuring one of them. You could also get hurt try to stop the fighting. If you don't want to rehome him, I would get into into training immediately with a professional behavioral expert. They may be able to help you with his aggression so he can live safely with your other dogs. You can ask your vet tomorrow for a referral to a behavioral expert.

Your question is cut off, but if Igor is showing aggression toward other animals, I highly recommend talking to and working with a trainer or behaviorist near you. Usually, training related to nerves/aggression around other animals is worked on with Behavioral Adjustment Training (BAT) or other desensitization techniques to keep your dog from reacting negatively toward other animals (or the object that is causing the trigger.) While this site is mostly US-centric, there are listings for behaviorists world-wide that may be able to help. http://www.dacvb.org/about/member-directory/

There are many possible reasons for this, I'm afraid - aggression is a complex behavior issue, so it can be hard to provide a succinct answer in this format. Many dogs develop aggression issues related to fear or anxiety around the age of 2-3 when they reach social maturity, so it's possible that this may be the issue. Or, since I see that Chucky is a bit older than that, he may have a medical problem causing him to be painful or uncomfortable - this is a common reason for "new" aggression in a previously friendly dog. I would recommend having Chucky examined by a vet as a good first step - he/she can check for anything that may be causing him pain or making him not feel well, and get him started on treatment if needed. If everything is normal medically, then it would be best to make an appointment with a veterinary behaviorist to help you determine what is causing the aggression - he/she can observe your dogs in person and also give you a step-by-step treatment plan to work on the issue.

I hate to hear that about Archie. Unfortunately it's impossible to know why he is doing this without analyzing his body language. Canine aggression is a complex behavior as it can stem from dominance, possessiveness, fear, anxiety, resource guarding or a combination. Unless you are very familiar with reading canine body language and training, I recommend to work with a professional trainer to achieve best rests. Certainly familiarizing yourself with canine body language and dog training can help you to recognize what your pet is trying to say before a bite happens. You can find many books written on the topic. Once you understand the underlying cause, appropriate behavior modification can begin. Best of luck.

Thanks for using Petco Pet Education Center, formerly Petcoach! This is just likely a display of dominant behavior. These types of behavior can improve though this does require in person training with the help of a qualified dog trainer. I would encourage you to contact a dog trainer that can work with you and Tova in person to really take care of this behavior. The sooner these behaviors are dealt with, the more likely it is that you can improve and resolve them. Good luck and have a great day!