First with the way on how we biologically manufacture things. In the book "A Brave New World", we see that people are born through the normal way, but having them being made and classified into a certain group. And I quote," The principle of mass production at last applied to biology"
pg. 19. We also see this in the world that we live in, but in a different manner. Today we see and hear things about scientist cloning our livestock. Mostly cows. The reason why I see this relating to the quote on pg. 19, is because the author sees this as the first step to later on cloning and making human beings. He sees today's world beginning to experiment and beginning to play God. To keep this world organized. It hasn't started, but you can say that the first phase has already begun.
Another thing he sees is how these created life forms from the book "A Brave New World" are raised almost the same way as the people from our world. Like, and I quote,"day most games were played without more apparatus than ball or two; a few sticks". He's implying that most kids don't even play outside like a "normal kid". He relates this to our world, how kids today don't even play outside. Most are having fun with their brand new tablet, or brand new video game system. Or their on their phones checking social media. I know this because when I was 5 or 6 I already had my first playstation. Heck, I never ever went outside cause of it. What I'm trying to say is that the author is showing us how the kids from his book are almost raised the same way as the kids of today's generation.