minecraft-assets/data/minecraft/pig_variant/_all.json

{"cold":{"biomes":"#minecraft:spawns_cold_variant_farm_animals","model":"cold","texture":"minecraft:entity/pig/cold_pig"},"temperate":{"texture":"minecraft:entity/pig/pig"},"warm":{"biomes":"#minecraft:spawns_warm_variant_farm_animals","texture":"minecraft:entity/pig/warm_pig"}}