Maybe, it depends, I probably would have the same spellcasting requirement as alchemy, and make it livestock only, hence craft livestock, because if its animals, crafting wartrained legendary tigers is a go, and everything, you can bet they'll start making angels and dragons and ask for prices for those things. Still at low levels, animals can be rather powerful (More so in 2nd ed, two 2nd ed light warhorses sometimes were as effective as the PC with them, when he got them to attack). If I don't want something like that in my setting, no, if it's added mid game, I'd have want an explanation, and make townspeople say "That ain't natural, it ain't right." and if they know how it was made, be cautious to buy it, though the PC doesn't have to tell.