These animals can feel pain and suffering. They are sentient. I think they are conscious, but these particular ones probably not self-conscious.
Admittedly, we have introduced 'animal rights', but these amount to "You can kill the animal, but in this specific manner." We keep them in small cages and in unnatural conditions. We deprive them of most of their natural experiences. We put them in conditions that we know are stressful (releasing chemicals that we know cause stress or anxiety in humans).
In my opinion, in many ways current LLMs are more intelligent than these animals. But LLMs don't feel pain while the animals do. I think that's more important to take into account. So why are we suddenly striving for model welfare before animal welfare?
PS: I'm not vegetarian, so I'm as much as a hypocrite about this as the next guy.
[1] https://ourworldindata.org/how-many-animals-get-slaughtered-...