Canine Behavior/Will my dog attack puppies
My dad's dog Sandie had puppies on October 3, 2012. When she had that litter my dad let me keep one, I chose a male and named him Bruno. When Bruno was 6 months old me and my dad took him to the vet to get his rabies shot and to be neutered. About a month and a half ago Sandie got out of her pen and is pregnant again. When these new puppies arrive we are going to keep them indoors until they can walk by themselves, after that we are planning to put them in the same pen as Bruno and Sandie are in now, it is a very large pen and it is outdoors. Bruno hasn't met but two dogs in his life, the one was a chow mix and he lives on the same property that our dog live on, Bruno didn't have any problem with him at all. The other dog looked to be a pitbull, Bruno met this dog at the vet the day he was neutered, and Bruno freaked out and wouldn't stop howling until that dog left the room, but he didn't want to fight this dog he was just terrified. My question is, would it be Ok if we left Bruno in the pen with the puppies when they can walk, or should we separate Bruno into another place?
Thank you for your question.
For the health and safety of the puppies, they ought not be living outdoors until they're at least 10 weeks old. And at that point, they need to have proper shelter available that is out of the elements and climate controlled. Puppies and young dogs are not able to regulate their body temperature as well as adult dogs. So they are more sensitive to extreme heat and extreme cold/wet. So, even once they're outside, they need to have shelter that is off the ground, out of the sun and maintained at a controlled temperature that is neither above 85 degrees nor below 60 degrees. And, of course, they will need to have plenty of fresh water available at all times.
As to whether or not they should be housed with Bruno, it's hard for me to say without having observed his behavior with other dogs, and specifically puppies. You said that he gets on with another dog on the property, but seemed frightened by a new dog he met in a high-stress environment (the vet's office). From this it's really impossible for me to know if Bruno is comfortable with dogs or not.
More importantly, just because a dog is comfortable with other adult dogs doesn't mean he will be comfortable with puppies. Many dogs are very dog-friendly but rather put out or even intimidated by puppies. Puppies don't smell like dogs yet as they've not yet gone through puberty which means they've not yet had the hormone surges that make them smell "right" to other dogs. Further, puppies are filled with unending energy and don't read canine body language/etiquette very well. Puppies are pushy, invade the personal space of others, torment others in their efforts to try to play, often ignoring the warnings given by others to back off. They move quickly and sporadically, they have loud, piercing barks and will often vocalize for no discernible reason. This can all be agitating for adult dogs if they're not socialized to puppies.
I would not leave any puppy alone with an adult dog until I've supervised several interactions and see clear tolerance from the adult - repeated back-off signals that are done gently and consistently without escalating (e.g. warning growls or air snaps that never go further into actual contact or bullying). I also want to see that the puppies are heeding these warnings without tormenting the older dog or needing the human to intervene.
Some dogs really love puppies and that's a beautiful thing to watch. They are so patient and tolerant and are really gentle when correcting puppies. They allow the puppies to get away with harder bites during play or nagging for attention and never get overly angry. As the puppies grow up, the adult dog slowly gets firmer with the corrections and a bit less tolerant - as the puppies are figuring out what those signals mean. That dog will demonstrate a great trustworthiness around the pups. But not all dogs are this tolerant nor interested in parenting puppies.
It would be entirely unfair to Bruno to put him in a pen with a bunch of puppies (even a single puppy) if he's not truly comfortable with puppies. It would also be entirely unfair to put Bruno out of his regular living space to accommodate the puppies. Your best solution here is to create a second enclosure for the puppies.
If this were happening at my home, I would have several supervised interactions between Bruno and the puppies to see how Bruno feels about them. I'd start by introducing him to just the calmest puppy in the group. I'd be on hand to separate them if he starts to bully the puppy or if the puppy is nagging Bruno and Bruno isn't enjoying it. If a couple visits with this puppy goes well, then I'd introduce him to the next calmest puppy and so on until he's met each on individually. Then I'd introduce him to the two calmest puppies together, then the next two, etc. And if all is going well, then I'd introduce 3 at a time, etc, until he's got the whole litter there. Each new puppy in the space changes the dynamic tremendously and while he may be OK with one or two puppies, he may be entirely overwhelmed by 3 or more. Our goal is to make sure Bruno is comfortable with this.
I'd also plan to have two separate enclosures near each other. This may be side-by-side where they can sniff and lick at each other through the fencing, or it may be several feet apart or it may have an opaque barrier so they can't see each other - depending on how comfortable Bruno appears to be with them. I would NOT allow unsupervised time with the puppies until they are 6 months old, and they and Bruno have all demonstrated that they get along and heed each other's behavioral signals.
I would also get the mama spayed so that there are no more oops litters. There are already an overwhelming number of dogs and puppies in shelters (~4 million put to sleep each year for lack of homes) desperately looking for their forever home. I don't want to be responsible for one of those loveable and homeless dogs being euthanized because I allowed my female to make babies. Especially when she's proven that during her fertile time, she is an escape artist and will do anything to get with a guy... I'm sorry if this bit is rather blunt, but sometimes being straight is better than sugar-coating.
I do hope this proves helpful to you. Please feel free to followup if I can be of further assistance.
Los Angeles Behaviorist