Can you tell me what you think of this speech? And tell me anything that I can do to make it longer thank you?

I would add examples. You tell what everything is, i.e. pheotype, genotype, and selective breeding, but you don't give any examples. There are many other areas where you can give specific examples. Since I really know nothing about what you are saying in your speech, it would be easier for me to hear examples of well known animals so that I can relate what you are saying to what I already know. Build off general background knowledge of your audience, and then put in parts for people that may not know as much about your topic. That's always the easiest way to make something longer.