If you are currently a vegan (someone who eats no animal products at all), congratulations! A vegan diet has been shown to improve your health, keep cardiac/stroke/diabetes/other chronic and serious diseases at bay, help keep your weight within healthy parameters, and extend your life.
For the rest of us who have never met a rib eye we didn't like, consider the possibility of at least going vegan a few days a week. Aside from the health benefits of doing this, this sort of practice will come in handy if there should be a long-term disaster.
I can't remember where I read it, but in a recent post somewhere, a lady from Puerto Rico noted than many people have changed their diet to vegan or mostly vegan for the simple reason that there is no electricity in many parts of the island which means there is no refrigeration. Animal products (meat, milk, eggs, etc) require refrigeration lest they spoil. Vegetables, fruit, legumes, and grains don't require refrigeration thus the change to their diet.
Consider that you can keep a lot of grains (rice, wheat, corn, oats, etc), legumes (dried beans and peas), dried fruit and vegetables, etc. for ages, in a non-refrigerated place. In addition these items are usually cheaper than animal products to purchase, and a little goes a long way (most grains and legumes when cooked swell up considerably--a cup of oatmeal cooked can easily feed at least two people).
Remember that if you do go 100% vegan, you may need to add some supplements to your stockpile, especially Vitamin B12 which is only found in animal products.