Why do you want to go vegan. It's bad for you. Plenty of "herbivore" animals will eat meat when they have to.

Eggs are not cruelty - chickens will produce them whether you eat them or not.

Dairy is not cruelty - most cows graze in fields or eat all the byproducts crop farming.

Eliminate meat farming and there will be mass starvation
The 1/3 of grain produced that is unfit for human consumption due to spoiling and contamination, can't be sold anymore. Currently this acts as a gigantic subsidy used to feed farm animals and supports current grain prices. Once it's thrown out and the -50% yield is factored into the price, it suddenly makes grain (bread et al.) extremely expensive.

Eliminate meat farming and you lose the fertilizer produced by these animals.

Meat is the best source for iron. Look up "bioavailability". Many plants that contain iron also contain chemicals that interfere with a person's ability to absorb those minerals.