On a small homestead farm, I'm finding that producing one's own meat is quite do-able. Or growing produce to use for trade to get local meat also works. The main hurdle I see on raising your own on a farm is getting past the slaughter aspect. But then, there's always the local slaughterhouse to resort to for those who haven't gotten to the point of doing it themselves.
In my own endeavors to become self reliant, I've gradually added various livestock to see if they would fit into my farm.
Chickens :
I started out with chickens. First of all, I like to eat chicken and eggs. That was the first plus of starting with chickens. Next, they are small in size. They can't damage me very badly. They don't require a big investment. You can start out with just one until you learn about them. They produce eggs without having to kill them. Slaughter and butchering is not complicated. Just about any small farm could raise a few birds.
Rabbits:
I got into rabbits only this past year. Looking back, it would have worked out just fine if I had added a couple rabbits in the very beginning. A small farm can easily support a breeding pair. The initial investment is low and the return is quick in the form of meat for the dinner plate. Home slaughter is uncomplicated. They are not difficult to raise nor dangerous to keep.
Sheep:
I find sheep to be a good homestead animal, especially for me. They are easier to confine than goats, do a good job at eating grasses, and aren't exceptionally dangerous. Well, I'll modify that statement....ewes aren't very dangerous. Rams are a different story. But in general, they aren't a difficult animal for me to keep. Since I changed to having only bottle fed sheep, I'm finding it far easier to deal with them. My farm can easily support a small flock. I currently have 11 and am aiming for a flock size of 15 ewes, 1 to 2 rams. While sheep could be milked, I'm not ready to try training a ewe yet. So I keep them for meat and sellable lambs. Sheep are easy to home slaughter and not too big. One will fit into the freezer with no problem.
Goats:
Like sheep, I find goats to be a good homestead animal. But they are different from sheep. They are escape artists, so they need more secure fencing. And they tend to be browsers rather than grazers, though they will indeed eat grasses. Personalitywise, sheep and goats are different. I like both. Goats are often the choice for homestead milk, but they are also good meat animals. As with sheep, I find them easy for home slaughter and butchering.
Pigs:
In my opinion, a pig is another good homestead animal. They are reasonably easy to confine and feed. They produce a lot of meat. Home slaughter is more involved than the other animals I've mentioned so far, but it's not beyond the scope of a homesteader. This past year I finally added a couple pigs to the farm.
Cows:
In the past I've had enough firsthand experience with cows to know that I don't wish to deal with them myself. They are big, strong, opinionated, don't necessarily respect fencing, and could hurt me in a big way. To keep a cow safe to work around, one needs to work with them at least a little almost every day. Oxen drivers and 4-H'ers work closely with their cattle, making the animals rather safe. But most small farmers don't have the time to do that. I know that I surely don't. Although a cow would not be a good option for me, I'm certain that other homesteaders would find a cow to be just fine. I have seen some other small farms around here with a dairy cow or two where it works well for them. Of course a big animal like a cow requires a lot of feed. A very small homestead most likely could not support a cow. My size farm could support a cow if there wasn't already have competition from a lot of ither livestock. but right now I'd need to create more pasture if a cow was to be added. As for meat, a cow could fill the freezer. Plus home slaughter and butchering is a big task. And beef does best if hung for several days, a situation most homesteaders can't do themselves. The bottom line, in my opinion raising a beefer isn't a good sustainable meat option for my farm. I'll just trade my excess eggs, lamb, or rabbit for beef.
Fish: I haven't yet expanded into producing my own fish. First if all, hubby isn't a fish eater. So there's no pressure to get into fish raising. But I enjoy fish now and again, so I've thought about raising tilapia. From what I've read, raising tilapia or catfish is do-able for a small farm. Each do well in a simple pond. Feeding them is not complicated. Currently I have 3 tilapia in my ag catchment tank. Well lets say that I put three into the tank and to date none have floated on the surface. The tank acts like a pond, growing edible greenery. Mosquito fish also live in the tank, so their fry would be a food source for the tilapia, too. It looks like keeping fish on a small homestead would work, especially species that are not fussy. A small farm could easy support them.
There are plenty of other meat sources that could be kept in a sustainable fashion on a small homestead, but at this point I'm not interested in them for meat. Perhaps some day in the future I'll give others a try.