I'm in the same zone as you, more or less. It really is a great climate for veggies. Here are some things that grow well for me grocery-wise, though I don't know what makes good animal feed.
In the winter, I mostly grow Brassicas. They need very little maintenance once they're established, though some protection from cabbage moths early in the season was necessary for me. The whole plant is edible, which means you can give the animals all the parts that you don't want to eat. Right now, I'm growing broccoli (Calabrese and Romanesco), Brussels sprouts (Long Island), kohlrabi, kale, turnips, and collards (Georgia). I also have carrots, onions, garlic, beets, parsnips, leeks, and chard, which will grow over winter without protection here. I haven't grown them yet, but fava beans are supposed to be hardy and very productive here in winter.
In summer, of course the options are wider - tomatoes, peppers, squash, corn, beans, eggplant... all the typical garden veggies grow well. I grow potatoes and sweet potatoes - the sweet potatoes were very productive for me this year, require almost no attention, and the vines are edible as well as the tubers. They grow well in large containers if you don't want to have to dig them out of the ground at harvest time.
In spring and fall, I grow bush beans, peas, beets, spinach, lettuce, more chard (it actually grows 12 months here), and carrots... and of course, the overlapping beginning or end of other crops - there isn't a week out of the year where we don't harvest something.
I don't have a lot of perennial edibles, but strawberries, blueberries (southern varieties do best), hardy kiwi, and bush cherries are all growing and should be producing well in a few years. With the kind of space you have, you could definitely put in raspberry or blackberry plants as well, as long as you can keep the animals from eating all the fruit.
I am confined by being in a small space (1/8 acre including the house and a lot of shady areas), but am still able to grow far more than my husband and I can eat. We buy groceries, but have been able to cut our bill by about 75% since we started growing food. With 7 acres and livestock, I don't doubt at all that you can get your bill to net zero, but it will be a fair bit of labor.