Swim Bladder is the answer for sure
The benefit to a society if everyone reduces the amount of meat they eat is that it will help the nutrient cycle. It could also reduce the amount of nitrogen going to the environment. Thank you for posting your question. I hope this answer helped you. Let me know if you need more help.
The deer population would drastically be reduced with the slower rate of reproduction and predators that would kill more deer than can reproduce. The environment would likely also have a reduced population of predators for deer, since the food source is reduced.
The stimuli sends a message to the brain
Hope this helps