I don't know if I ever started reading the book, or if I never gave it a chance, because I was so put off by Singer's utilitarianism.
I turned vegetarian in the mid-nineties because my first girlfriend was vegetarian. It coincided with media focusing on unnecessarily long animal transports in the EU, and I quickly realized I didn't want to take any part in factory farming. My wife turned vegetarian after meeting me, and we're both vegan since 2007. I joke that vegetarianism and veganism is transferred from partner to partner. Both our kids have been vegan their whole lives.
I came in contact with Singer's ideas in articles, and was both put off by the utilitarian ideas as I couldn't see them coexist with ideas of inviolable human and animal rights, and also that he used mentally disabled children as an example of the absurdity of using mental capacity as a measure of whether you can be used to make food and clothes. I agree, of course, that you shouldn't use human children or animals, it was just that the examples and arguments didn't speak to me at all.
Do you remember what it was by Singer that spoke to you?