The gemara stated that the blood of a hekdesh animal (or any animal) is considered part of its body. The milk and the peresh are by products that are processed by the body but not a part of it.

With that in mind why is it that the honey of bees which is a product of non kosher species is kosher but the milk of a camel or donkey are non kosher is not kosher?

Sam Kosofsky