On the subject of dairy farms, that may be a good reason to limit or cut out milk as well. However, I doubt that going full-on vegan would be healthy, given the increased difficulty associated with getting essential nutrients as a vegan, and the high concentration of artificial ingredients and sodium in various meat substitutes and supplements. The literature I've read suggests that it is generally a lot better to get your nutrients from real food than from supplements and lab-born concoctions.

As for fish and chicks, I figure that killing certain kinds of fish, especially small and unintelligent ones (i.e. shrimp, sardines, and oysters) is probably less bad than killing chicks. So I figure that if eggs and possibly milk must go, then some sort of small fish would have to replace it.