Sound of villager being hurt upon entering world

Every time I enter this particular world, there will be sounds of villagers getting hurt. After around half a minute, it stops.
No. of Villagers: >180
-Overground: >120
-Underground: >50
No. of Iron Golems: >15
No. of wooden doors: 90 - 120
Breeders: 2
Breeder Size: Both 9x9 (11x11 including walls)
Help?