Just as we reject racism sexism ageism and heterosexism we reject speciesism. The species of a sentient being is no more reason to deny the protection of this basic right than race sex age or sexual orientation is a reason to deny membership in the human moral community to other humans.
Mom and Dad were married 64 years. And if you wondered what their secret was you could have asked the local florist - because every day Dad gave Mom a rose which he put on her bedside table. That's how she found out what happened on the day my father died - she went looking for him because that morning there was no rose.