I assure you, star, that they are not despawning in the normal way. One day they were there, they an hour later I log back on and my cow and sheep farm are empty! They aren't old either because I am constantly breeding my sheep and cows. At the moment I have found some of the mild spawns that roam the feilds and shoved them in my house farm. I found 3 cows and 4 sheep. But I still want my colored ones back because it was hard to make all the dye. I couldn't care less about the cow farm as they are just meet and had nothing special about them.