Pollution: factory farms create so much excrement and harmful gases that cause water, land and air pollution. The pollution from animal waste causes respiratory problems, skin infections, nausea, depression, and even death for people who live nearby. 51% of global warming is caused by animal argriculture. 

Animal welfare: chickens live in spaces the size on an iPad, animals forced to survive in their own excrement, beaks and tails chopped off with no anaesthetic, male chicks ground to death alive, female cows hooked up to milking machines their whole life with their children taken off them and murdered until the point where they are not "profitable" anymore and then they are murdered as well. 

Your health: the standard chicken now has 40% less protein and 66.6% more fat than 40 years ago due to the mass of chemicals pumped into animals causing them to grow abnormally in states they are not supposed to handle and the disparity producers have for profit. Dairy and various other meats are  known to cause multiple diseases and cancers. The world health organisation has stated a vegan diet is the healthiest when done correctly. There are so many ways to obtain the necessary vitamins etc without animal products which are much healthier and better for the environment.  

We need to save the animals, the planet and ourselves!