I recommend https://​​welfarefootprint.org/​​
They do literature reviews, quantify and summarize the main sources of suffering for various farmed animals.
I wrote these two comments about farmed chickens based on their work: https://​​forum.effectivealtruism.org/​​posts/​​3EimeEtikzrTusqYy/​​animal-welfare-ea-and-personal-dietary-options?commentId=f8MsonDHxHRTvSb25
I recommend https://​​welfarefootprint.org/​​
They do literature reviews, quantify and summarize the main sources of suffering for various farmed animals.
I wrote these two comments about farmed chickens based on their work: https://​​forum.effectivealtruism.org/​​posts/​​3EimeEtikzrTusqYy/​​animal-welfare-ea-and-personal-dietary-options?commentId=f8MsonDHxHRTvSb25