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Canine Behavior/Introducing puppies to existing dog.


I recently rescued 2 mongrel puppies (1 male, 1 female) but i'm having trouble with my 2 year old rescue dog (very calm, happy dog, rescued from a shelter and very comfortable with our other dogs, Taken to the shelter when abandoned as a pup, No history of human or dog aggression).
This isn't the first time we have introduced a new dog to the pack and haven't had problems before.
First thing i did when the puppies came to the house is hold the puppies and let the older dog have a sniff and she was totally calm and had a good sniff before walking away.
I have kept the puppies away from the other dogs as they are still only 9 weeks old.
Now when i put the puppies and older dog on either side of a glass door the older dog looks like it wants to kill them!
Her ears are back but not flat to the head, Her tail's normal position is up anyway but is up and wagging, Teeth bared, Eyes narrowed,Really deep throaty growl, Head low, Front legs straight out.
Another strange thing is she does this until the puppies bark at her then she walks away.
Can you explain the older dogs reaction?
Is there a recommended procedure to introduce the puppies.
This might be a stupid question but could the fact that one of the puppies is female and all our other dogs are male be the reason for her behavior?
Thanks and best regards

At 9 weeks, it's unlikely the puppy has sufficient pheromones (especially through a glass door!)  It appears your older bitch doesn't "recognize" what "this is" until "it" barks.  Separating the dogs is most likely not a very good choice, at least not ALL the time, since the remainder of your pack has no way to integrate these pups unless the pups are among them.

I want you to conduct a test:  Providing the 9 week old pups have received (minimally) one vaccination, and providing you stay on YOUR PROPERTY (where Parvo and Distemper virus does not exist, let's hope, in the soil): put both pups and the 2 yo bitch on leash.  You handle the 2 yo.  Have others (close friends or family members) hold the leashes of the puppies.  Take the 2 yo out first; ask for a "sit", praise.  Then have the two pups come out, one after the other.  Do not allow "nose to nose" at first, simply walk them parallel to one another around the yard or safe area, with distance between them (a few feet).  If your 2 yo reacts in a manner that is not acceptable, stop walking her, hand the leash to one of those with a puppy, and continue on. By passing the leash to someone else, you are separating yourself from her which is a negative reinforcer.  Wait for her to calm, swap back.  Walk a minimum of 15 minutes a day. This parallel walking must take place every single day for the next (at least) week unless the 2 yo demonstrates active aggression (ears forward, tail up, showing of teeth, barking rapidly, snapping).  

A tail "up and wagging" means nothing except that the dog in question is making a statement of social hierarchy, is excited (rapid wagging of tip of tail), ears can be flat back, laid back (this demonstrates confusion) or perked forward (demonstrating high social hierarchy.)  I think the main problem here is THE GLASS DOOR.  She can't smell them, she can only react to what she SEES and her cognition does not translate: neonate dog.  Once in person on these excursions, she should be ready to be allowed to interact with them indoors providing there is no sudden and alarming response.

It is a huge error to acquire too many dogs, regardless of your purpose (which is obviously humane and loving).  It takes experience, knowledge of dog psychology and culture, and a clear place of high rank in social hierarchy (which is done psychologically by the human, no punishment, etc.) for a true "pack" to live in peace with one another.

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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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