There needs to be some way to get rid of excess meat (possibly turn it into animal feed)
Assuming your people consume sausages and meat in the same quantity, every chicken carcass produces 9 additional meat which backs up production of your sausage. At the point in the game where you unlock sausages, you might not have unlocked food packs nor see a reason to do so. As a result, you generate all this extra meat and can't do anything with it.
I'd suggest being able to turn it into animal feed. Add some challenge by requiring it to be combined with corn or some other crop. Corn gives a 10% bonus when it's converted into animal feed so maybe with meat, it gets a 20% bonus. Something like 20 meat and 40 corn making 72 animal feed. Whatever number you choose for the meat, don't make it divisible by 9 or people are just going to make ratio-perfect blueprints for their chicken farms and sausage factories.