Sheep taming possible bug?

[Kumodo]

OK i have tamed horses and cows. We have about 6 horses and 4 cows. I know the process, so i think.
Anyway, each time i grab a sheep with clover and hitch him to the post. I know i have to wait 12 hours or more for the sheep or animal to get into his combat stance.
The problem is that i have captured 14 sheep in total, over the past month.
Each time i wait for them to enter combat, they go over 12 hours+ and have no combat stance and vanish within 24 hours I think maybe 2 of the 14 took a stance, i beat them in combat easily and then the next day they are gone..POOF.
As for the other 12, none of them enter combat and vanish within 24 hours. Caught one yesterday at 620 pm. Today at 10:45 AM, no combat stance yet, but i know he will vanish like the rest.
All animals are in a large palisade with food troughs , no way out.
Is this a bug? or is this a random generator issue? or am i not doing something correctly? I just find it odd that i have only seen 2 of 14 in a combat stance, none for the rest and they vanish within 24 hours of waiting. I did not have this problem with horses or cows.
I haven't tried boars yet, think il just move on to that for now, until i figure out what is going on.

[Kumodo]

Update in case anyone cares.

Just as i suspected, the last sheep did not go into a combat stance in 36 hours and i logged off for bed, slept 7 hours, logged on before i went to work , just to check....and gone.

Sheep 16 , caught him yesterday at 620pm , it is now 7:06 pm the next day . No stance as of yet.

[MagicManICT]

Just wanted to note another player just had the same issue with a horse: viewtopic.php?f=42&t=50553

[Kumodo]

My Neighbor is having the same problem. I gave up 17 sheep, 2 combat stances with different sheep, then next day gone, the 15 that never went into combat vanished between 20 and 36 hours, yes i checked. They are in palisade used to tame horses , cows, boar..never had a problem . It cant find any info to support a bug or that im doing something wrong.