Introducing to Other Dogs
Introducing a new dog into any household is actually a lot more complex than most people imagine it to be. Many owners make the mistake of viewing the situation through human eyes: "Oh, a new friend for Pita! She'll be so happy," etc etc.The truth of the matter is that, when a new dog is introduced to the household, a certain challenges arise as the dogs sort out their social hierarchy.
The dogs will evaluate each other. This may be done more forcefully than you had imagined - it all depends on the individual personality and leadership drive of each dog. There are two possible outcomes to this situation:
One dog will signal his submissiveness to the other. This will be signaled through his body posture. He will not maintain eye contact, he will turn his snout to one side, his head will be carried lower than the other dog's. If this is the case, it shows that the social order has already been sorted out. You can relax, because the dogs now know how to act around each other and how to avoid unnecessary fights.
Both dogs will match each other in terms of confident, assertive body language. Both of their heads will be carried high, eye contact will be direct and maintained, ears will be raised. If neither dog backs down, the only remaining way for them to sort out who's the boss is through a direct physical challenge. In short, the dogs are going to "scrap" or fight, and this will probably happen very quickly - often within seconds of the initial meeting. This tussle is entirely natural: the dogs MUST sort out who outranks whom, because without a defined social ranking system they will squabble and bicker endlessly. (If they don't get to sort things out now - for example, if you separate them before matters are resolved to their satisfaction - you're really just delaying the inevitable: they're still going to have to sort things out at some point.)
If we lived in an ideal world, nobody would finalize the adoption of a second (or third, or fourth ...) dog until all canine members of the household - both existing and potential - had had an opportunity to meet, greet, and accept each other. Of course, it goes without saying that we don't live in an ideal world: in plenty of cases, owners don't have the option of introducing potential new dogs to existing pets before bringing them home. This can happen for a variety of reasons: perhaps they weren't aware that the dogs might not get on; perhaps the new dog came from a distant breeder and had to be shipped across country; perhaps the new adoption was a spur-of-the-moment decision (although we devoutly hope not!).
If you've brought a new dog home without allowing your existing pets to check him out first, there are a couple of things that you can do which will go far toward ensuring a smooth transition for everyone concerned:
Extensively exercise all dogs involved prior to the meeting. This will allow them to work off any excess energy and agitation. Take them all for as long a walk as you can (upwards of an hour, if that's possible), and try to introduce some "brain-tiring" work too: obedience commands, random walking, anything that involves mental activity for your dog.
If you have more than one dog in your house already, and if they're in the habit of revving each other up on walks, you might take them out separately.
When you do introduce them, do it in a neutral setting. If you bring the new dog straight into the house without allowing them to meet each other first, this places unnecessary duress on your existing dog(s), and calls all sorts of unwanted instincts into play (like the need to defend personal territory). An unfamiliar park with few distractions would be ideal: this way, territorial aggression won't play a part in determining their reactions to each other.
If you already have more than one dog in your house, introduce the new arrival to each one separately BEFORE allowing them free rein together. This will prevent a "pack mentality" from evolving: the presence of other dogs seems to encourage even well-mannered canines to get edgy, snappy, and generally to misbehave.
Introducing to Cats
Some Dachshunds are dedicated cat-chasers, while others are comfortable with neighborhood cats making an occasional detour through the backyard. Even if they're not, the average cat can take care of itself pretty well, so this isn't usually cause for particular concern. But when you ask a cat and a Dachshund to share the same living space, real problems can develop. Before introducing a Dachshund into a household that contains a feline, it's worth preparing yourself mentally for the challenges of the next few weeks.
Dachshunds have a higher "prey drive" than other dogs. This means they're strongly compelled to chase and kill small, fleeing creatures. Prey drive goes above and beyond the normal canine instinct to chase: most Dachshunds will give enthusiastic chase to a running cat, but won't go to extreme lengths; a preydriven Dachshund will really sprint all-out, and will maim or kill that cat if he can catch it. In short, a strongly prey-driven Dachshund is a danger to any and all cats it encounters.
Of course, all dogs are individuals. Some will never show an interest in chasing your cat, and of course the converse is also true. Essentially, when it comes to introducing a Dachshund into a house that contains a cat, all you can do is take pot luck. Even if you choose a typically mellow Dachshund, from parents who have cohabited peacefully with cats all their lives, and from a breeder who's given the go-ahead in terms of prey drive, there's still no guaranteeing that the Dachshund you choose is going to be OK with your kitty.
The introduction itself is the most important part, since it sets the tone for the duration of their relationship - but even if it goes well, be aware that problems can still develop later on. You may need to be prepared for drastic measures (such as re-homing the cat) in order to save its life.
Here are some hard and fast rules for introducing a cat to a Dachshund:
The Dachshund MUST be on a very short leash. A head collar is even better: you want to stop him from lunging at the cat before his front paws even leave the ground. How you allow him to behave now will set the standard for future behavior, so if you can keep him calm, the first step has been taken towards ensuring a mellow cat/dog coexistence. Keep your eye on him very closely, and watch his reactions to the cat. Are his eyes narrowed? Is he licking his lips in anticipation (yes, this does actually happen)? Is he tense, with his ears pricked up and tail erect or switching stiffly from side to side? These are all typical postures of a prey-driven dog when confronted with potential prey.
Don't leave them alone in the house together until you're SURE that a cease-fire - however grudgingly - has been reached. Even if you're certain of the cat's ability to escape, it's likely that the Dachshund's efforts will be significantly more frenzied (and persistent) when you're not around.
Always leave the cat an "out" when leaving them alone together, and NEVER shut them in the same room. Your cat needs to be able to get out of the house if necessary.
Other Pets
There are some pets that you could never, ever trust your dachshund to be around unsupervised under any circumstances. These would be:
Rabbits
Ferrets
Mice
Birds