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Canine Behavior/Aggressive behavior with animals


We have six year old mix breed named Oreo.  Our vet says he is a mix of black lab (full blood mother)and rottweiller and chow.  He weighs approximately 100 lbs and lives on our small ranch with his runt sister who weighs 55 lbs.  For the first 5 years of their lives, they lived outside with our other older dogs who are no longer with us.  They both had to be put down earlier this year.  Oreo has had very aggressive behavior towards all animals other than our other dogs.  He has killed our barn cats along with other animals who have wondered upon the property during the day and evening hours.  We have taken him down to the park for long walks and as some dogs have walked by, he lunges at them for no reason as if to kill them.  My wife and I are about to take my mother in to live with us and she has a small terrier who I am afraid Oreo would kill at the first chance and I need to find a way to understand why he is like this and what can someone actually do to help him get over this issue.  He has never attacked any children or person for that matter as he seems to shy away from them when they come on the property.  He will bark at first as though he is protecting the property and once they enter the fence line, he and his little sister usually retreat to the back porch where they can be away from the workers or those who have come to the house.  I am sure I need to have an animal behaviorist come take a look at him to help us but I guess I am just looking to see why he is like this.  One of our older dogs was alwasy an agressive and I assume Oreo learned some of his behavior from him but I do not know where he learned to hate cats and other dogs so much.  The older dog who was aggressive, was only aggressive towards people and never to other animals other than our neighbors chickens if they wandered over towards our barn.  Hope you can give me some help.



I can't begin to help in this situation.  Oreo has demonstrated, over and over again, his very high prey drive and has killed many animals.  Of course he WILL kill your mother's dog, as soon as he is able, and on sight.  He is a clear and present danger to humans, as well, especially children and disabled older people, since his socialization was clearly not correct and he has lived his life mostly (from your report) as an independently directed "outdoor" dog.  A bitch in estrus can be bred by several dogs (males) and it is quite likely that Oreo and his "sister" had different sires (fathers), which accounts for their glaring dissimilarity in appearance.  No veterinarian can hazard a real "guess" regarding the sort of hybrid the dog is but, from my experience, the most common hybrid variety with the Labrador Retriever is the Pit Bull (this was deliberately done by poor breeders to bring up "bone" in the Labrador and I've seen many such hybrids).  A Chow Chow mix could only be evident from color of tongue (black or black spots); a Rottweiler mix would be more evident from markings but you imbed no picture.

Having "put down" the older dogs has seriously affected this dog emotionally and psychologically.  His "pack" structure was seriously compromised.  The "reason" he is doing what he does can be attributed to this, as one factor, as well as to high prey drive, inappropriate training and socialization, and (perhaps) inherited fear problems (or even created fear problems).  

Yes, you need a CERTIFIED APPLIED ANIMAL BEHAVIORIST (not a dog trainer) but I can tell you that extinguishing Oreo's prey drive, at this point, in order to insure the safety of your mother's small breed dog (or your mother herself, for that matter) is most likely going to be extremely difficult and, at his age, perhaps impossible.

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Jill Connor, Ph.D.


I have spent my entire professional life rehabilitating the behavior of the domestic dog and I can answer any question regarding any behavior problem in any breed dog. I have answered more than 5,000 QUESTIONS on this site in the past (almost) eight years. If you are a caring, committed owner and need advice, I'm here for you. I am personally acquainted with my colleagues (Turid Rugaas, Ian Dunbar, etc.) who were members of an elite group in EGroups that I founded: K9Shrinks. THERE ARE NO QUICK FIXES for serious behavioral issues; not only is it unprofessional to offer same, it is also unethical. IF I ASK YOU SUBSEQUENT QUESTIONS, I NEED YOU TO INTERACT WITH ME. More information equals more credible answers and a more successful outcome. If you want ANSWERS THAT WORK, participate in any way I request. I'm quite committed to working on this site for YOUR benefit and the benefit of YOUR DOG. Help me in any way you can.


30 years of solving serious behavior problems in domestic dogs; expert in dog to human aggression; Internet columnist for for 5 years; former radio talk show host, WHPC.FM, Garden City, NY "Bite Back" (1995 through 2000). List owner, international animal behavior experts, Seminar leader: "Operant Conditioning and Learning"; "Aggression in The Domestic Dog"; "Solving Problem Behaviors" -- conducted for various training facilities on Long Island from 1993 through 2000. Former clinical director of "Behavioral Abnormalities" in conjunction with Mark Beckerman, DVM, Hempstead, New York.

Member, APDT (UK); Psychologists in Ethical Treatment with Animals

Harcourt Brace Learning Direct: "The Business of Dog Training" "The Fail Safe Dog: Brain Training, not Pain Training"

Ph.D., UC Berkeley

Past/Present Clients
Board of Directors: Northeast Dog Rescue Connection; The Dog Project; Sav-A-Dog Foundation; etc. Pro Bono counselor: Little Shelter Humane Society My practice is presently limited to forensics. I diagnose cause of dog bite, based upon testimony before the Court, for attorneys and insurance companies litigating dog bites, including fatal injuries. I also do pro bono work for bona fide rescue organizations, humane societies, et al, regarding such analysis in an effort to obtain release for dogs being held for death in municipal shelters in the US.

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