Actually, animal rights activists are concerned with all animals, from the great ape to the bee. In practice, their involvement is restricted to farm animals or animals which are kept by humans, ie to a very small percentage of the total of more than 1.3 million known animal species worldwide.
As animal rights advocates want animals have the same right to live like human beings, every imagination is, according to their imagination, murder. So, of course, every animal rights activist would be a murderer and would have to live behind bars all the time, because he also kills unidentified small animals every day, because he steps on them, for example.
Of course, this would be nonsense; it is controversial in the animal rights scene, to know from what level of development the rights should be applied. Some think that all animals, which are mammals, or are able to feel pain. Others want to include all the vertebrate animals, while others are also reluctant to eat honey, because bees are exploited, and also silkworms receive solidarity. There is a consensus that very primitive forms of life, such as viruses or bacteria, can not be included in the community of the same. On the other hand, the animal rights organization PETA has already used itself for Pokémon and criticized that the computer game with the virtual fantasies trivialized organized animal fighting in the real world.