How do you assert the sentience of a being to which you don't have epistemic access? It sounds like you're anthropomorphising animals and assigning them human characteristics that they don't actually have.
I'm a vegan, by the way. :-)
Choosing to do something to survive does not make it a de facto moral action. Survival does not determine morality.
I never said it did.
This is reality. Science demonstrates reality. Observe. Test. Open your eyes and investigate the lives of animals. They think. They feel. I didn't say we know WHAT they are thinking or feeling in all cases, nor can we say the same for other humans. We can know that THEY DO think and feel, though.
http://fcmconference.org/img/CambridgeDeclarationOnConsciousness.pdf
https://www.ciwf.org.uk/includes/documents/cm_docs/2009/b/boyle_2009_neuroscience_and_animal_sentience.pdf
https://www.psychologytoday.com/blog/animal-emotions/201306/universal-declaration-animal-sentience-no-pretending
https://www.psychologytoday.com/blog/animal-emotions/201208/scientists-conclude-nonhuman-animals-are-conscious-beings
http://news.nationalgeographic.com/2015/07/150714-animal-dog-thinking-feelings-brain-science/
As for that quote, I was preempting some justifications people use to justify actions based on survival, as I have found some explanations for "Natural Law" that use survival.
And I'm 100%, and more, glad that you are "vegan".
I have spent much time and thinking to understand the depths of moral applications, without using Mises or Rothbard, etc., to tell me how it works. I know it works by how our actions affect others, that it's a concept we created to describe our actions because we can understand concepts, and that's why morality is something that applies to us, and not other animals because they lack this conceptual abstraction sophistication.
Observing reality, shows animals feel, have emotion, and therefore think.