700 million dogs x 17 kg per dog = 12 Mt of dog

59 million horses x 700 kg per horse = 41 Mt of horse

If horses are 2%, then dogs are 0.5%, less than 1% just like they said

35 million camels x 500 kg per camel = 17 Mt of camel, a little less than 1%

I think the key thing is they’re measuring biomass, not just the number of animals, otherwise it would all be stuff like mice and rats (not to say that wouldn’t be a valid thing to look at also)