How would you make sure that a dog like a newfie or rottie won’t eat the chihuahua 
Lame joke aside. Hypothetical question
Can it be possible to have a toy breed and a giant breed living together in the same house? What about dominance issues ie a 10 month old rottie might challenge a 5 year old chihuahua?
has it been tried before?
We have a rat terrier (at a different time a Shi Tzu) and a German Shepard with no problems. (I know its not techinically a giant breed). We never really had any dominance issues with the small dog being older or younger. The large dog largely ignores the smaller one as its not in his usual line of sight, so the only danger is the terrier frolicing to much and getting a tail stepped on.
A couple I know owned (at one point) a Jack Russel Terrier, a Shih Tzu, a cat, a Great Dane, and a Yorkshire Terrier puppy.
At the time that the Great Dane joined the household, he was about the same size as the cat and the other two dogs, and about four months old(if I recall correctly) (the Yorkie came along later).
The biggest problem they had was this–the giant dog never quite seemed to understand why the rules were different for him than they were for the others.
The little dogs were allowed on furniture, on laps, etc. The big dog was not. Visitors to the house who were not dog people were overwhelmed by the Great Dane. The Great Dane was also a handful for his owners for all the usual reasons why a large dog can be a handful.
Unfortunately, the Great Dane died unexpectly at the age of 3 or 4. This is moderately common with large dog breeds, so the owners were not planning on replacing him with another large dog breed.
Last I heard, they had a mixed breed mutt retrieved from the side of the road. Said mutt should not be as big as the Great Dane, but still will outweigh the other animals put together.
We have a miniature dachshund and two boxers (also two other dogs). They get along fine. The dachshund is actually the alpha dog; the male boxer is scared of him.
I have 2 Papillons, about 8 & 10 lobs, and also have 2 Gordon Setters, in the 70 lb. range. I have had a few problems, with the Paps challenging the Gordies, and the Gordies take soooooooooooo much , and then they sorta go, “Y’know, I’m bigger than you…” and I have had a couple vet bills because of this. 
It CAN be done, but must be done with care.
Dogs seem to be completely unaware of their size relative to other dogs. So mellow dogs of all sizes get along fine. An aggressive larger dog is not a good match for a little dog. Other than that, mix and match all you want.
Horses are the same way - tiny teeny minature horses will try to breed draft horses. They get about as far up as the hocks - pretty funny to watch.
We have a 150-lb. Alaskan Malamute (3 y.o. male) and a 7 y.o. border collie/shepard mix (45 lbs.). The mal’s very much an adolescent in that he likes to playPLAYplayPLAY, but 1) doesn’t realize his own power, nor 2) realizes just how big he is. The little dog loves to play, too, but after being accidentally stepped on a couple of times, she gives little growls and dives for the nearest hidey hole when he flails around.
She (the little dog) does much better in a controlled situation. My husband walks both of them at the same time, and they’re as good as gold – they both obey their commands, the mal lets her have the right of way, they rarely quibble, etc. Same thing when either or both of us is/are in the same room as them.
We leave them alone in the house at times. No damage done when we return. The little dog usually has the run of the downstairs, while the mal camps out in our bedroom. They always come together, though, when they hear our car pull into the driveway.
So, to answer the OP’s question, big and little can get along. They both have to find their own levels of comfort. Just make sure the little one has a safe place to hide if the big one gets too rowdy, shower both of them with love and kisses, and they should be OK.
We’ve got a Greyhound and an Italian Greyhound. There’s no real trouble there other than the larger one thinking the smaller one’s annoyingly energetic.
My parents have two Irish wolfhounds, two Jack Russells, a minature pinscher, three border terriers, and a mutt. It’s a freaking zoo over there. The wolfhounds, much to their dismay, do not always get to be top dog. Size isn’t everything. Nora, the female wolfhound, is convinced she’s a Jack Russell since that’s what she grew up with. It can make playtime a little frightening for the smaller dogs, but in general peace reigns.
-Lil
Each individual dog can vary, so I can’t tell you if your specific little dog will get along with your specific big dog.
Still, it’s not uncommon to find a house where little dogs bully and dominate larger dogs!
Bear something in mind: each dog breed was meant for a different purpose. Many little dogs were bred for the purpose of killing rats. Many of the larger dogs were bred to be draft animals, beasts of burden.
People wanted drastically different temperaments in such dogs. They wanted a draft animal to be gentle and docile. They wanted a rat-killer to be aggressive and merciless. So, not surprisingly, many big dogs are much meeker than many little dogs.
Irish wolfhounds are about the biggest dogs on Earth, and Chihuahuas are about the smallest- but if you put an Irish wolfhound and a Chihuahua in the same household, my money is on the Chihuahua to completely intimidate the wolfhound! Wolfhounds are too gentle for their own good, while CHihuahuas are often mean little buggers!
It’s sad but true. I have a Jack Russel Terrier and two larger mutts. One is about 45 lbs, the other about 65lbs.) The JRT loves to lay on human chests (I think the heartbeat soothes him in some way). The other two get jealous and want to do the same, crushing the wind out of me.
Big dogs never seem to realize that they’re bigger than they were when they were puppies-- they think they can still do the same things they did then. One of my puppies used to run and hide beneath the couch when she was in trouble. One day she simply didn’t fit any more. She cracked her head and yelped in puzzlement, and began sniffing the couch as if to make sure I hadn’t switched them. (Humans do that.)
My grandma’s 110 lb. Airedale used to try to sit on my lap. Considering I’m only about five pounds heavier than that myself, hilarity ensued. He remembered being able to do that when he was a pup, and occasionally he would give me an accusing look as if to say, “You shrank your lap! Now where am I supposed to sit?”
The only big dog I ever knew to realize his size was a Great Dane that belonged to my mother. His name was Zeus, and Christ was he massive. His head was larger than my torso. However, he was as gentle as a butterfly, especially around children. I will never forget, as long as I live, seeing him play with one of the neighborhood kittens. The kitten was not much bigger than Zeus’s paw, yet it had him “pinned” to the ground, yanking at his collar. Zeus rolled around, always careful not to step on or lie on the kitten and they had a fine time. (Wish like hell I’d gotten pictures.)
When my medium-sized dog and the little dog wrestle, the bigger one lays down on the ground so the little guy can reach. From what I’ve observed, they seem to have an intricate etiquette of “what’s fair” in their wrestling, and if one takes advantage of the size difference too blatantly, the other will quit. I guess it’s less fun if there aren’t handicaps to keep things even.
Our family friends have a St. Bernard and a Westie. The St. Bernard is totally the Westie’s bitch. 
She’s younger than he is, but he’ll let her go first to the food bowl, climb over him when he’s lying on the floor, etc. Then again, terriers are by nature quite feisty and “bigger than their size”, so it’s not really surprising. The small terrier-mixes that live opposite my parents certainly have no qualms about trying to pick a fight with every single dog that goes by their yard.
The dog park I take Bea to has some very large regular visitors, including a massive Hovawart male (males usually stand at 63-70 centimeters at the withers; I’m willing to bet he goes to at least 75). Xero certainly realizes his own size; he uses it to police other dogs. If other males get into a scuffle, he will lumber over and place himself between the two parties and just. Not. Move. from that relative location until the others calm down, which they usually do when a giant male suddenly appears very close to them.
My BF’s mother has two dobermans and a toy poodle. They have no problems.
I used to have a 90 lb golden retriever and a medium size cat. They got on great, he treated the cat like a sibling. She would lay between his front paws when he was laying down and they would nap together. He would stand and watch her eat and drink from his dishes and wait till she was done to eat/drink himself. They were quite cute together.
I have a 10 pound Pekingese named Delilah (Dede) and a 100 pound Weimaraner named Chance. They cuddle up together to sleep and are best buddies. They can roughhouse since Chance is very careful not to hurt her.
It helps that my Weim is so gentle. For example, if Change is eating his dinner and Dede walks over to his bowl, he backs up and lets her have whatever food she wants without complaint.
I have pictures of them on photobucket. But I can’t figure out how to enlarge them for you guys to view.
