[danielam]

You've confused legal rights with natural rights. Animals don't have natural rights and (generally) don't have legal rights. They're usually legally regarded as property. Anti-cruelty statutes do not presuppose or imply rights. The absence of animal rights does not mean cruelty suddenly ceases to exist.

I didn't say we have obligations (or really duties) _to_ animals but _in respect to_ animals. This is an important distinction.

Animals do not have a right not to suffer, but it is immoral to be cruel toward them. I can, legitimately, cause suffering in an animal if it is an unfortunate effect of, say, acting for an appropriately commensurate human good. I cannot morally do the same to a human being.