Disappearing animals/mobs

The 2 previous bug fixes that were released have made my game unplayable because errors would occur and crash my game, as a result of these crashes i lost 3 of pets they just disappeared so i did what i could to fix the issue and the crashes atopped, but they continued after the most recent bug fix, this time the result of it was losing every mob/pet or animal i had at my base after 2 years of playing. this was my first ever world and just like that a majority of what i worked for is gone? i am very upset.