After re-reading this before submitting it, I have determined that it sounds very preachy, and for that I want to apologize in advance. My writing skills have deteriorated over the years. Please take this as it is meant, which is only as my feelings and a reflection of my experiences growing up. It is not meant in any way to be a directive of how to live your life.
My advise is the talk to the girls and find out if they are interested in this project. If they have no interest in participating, then don't push the issue. You cannot force them to appreciate the whole raising and butchering process, that is a decision that they need to make for themselves. Dialogue goes both ways. Listen to thier concerns if they have any.
What you can do is have frank and open discussions with them. If this is important to you and if you decide you want to raise some meaties to butcher, go ahead and do it. Allow them to participate as much as they want or don't want to do. Most important to me is that you have a good solid relationship with them. Allow them to have their own opinions and the right to express those opinions in a respectful way. But make sure that they also know that others have the right to their own opinions as well.
From all the comments posted here, it seems that most of the people who participate in raising their own meat are those that have either been brought up with the whole sustainable living lifestyle or have chosen that route - of their own free will. Be aware that it is a lifestyle. It will become part of who they are.
I was raised with hunting and fishing. Getting a dual purpose breed to raise for eggs and meat only makes sence to me. I learned to hunt and fish, mostly so I could spend time with my dad but I found out that I really enjoy being outdoors appreciating nature also. It has become a part of who I am.
this is a perfect well thought out responce I wish I had made it!