Confirmed. Have similar issues with wild boars.

Update: I've killed about a half dozen boar and a half dozen deer since opening the bug, but have not seen the behaviour originally reported. However, I have been using the improvised bow instead of the shotgun (which means I rarely land the first shot). However, the animals still appear to be unaware when I do hit them (I'm guessing because the bow is silent).

Experienced a similar issue. The deer was obviously stuck (didn't move at all). I killed it with a shotgun (heart shot) and I saw the deer colapsing for a short moment but it vanished. About 30m to the south the shot deer lay on the grass ready to be skinned which worked flawless.

--Edith--
As survivin stated, the direction fits quite well the escape route the deer would have taken.

Confirmed Zyryanoff's experience with wild boars.

Using sawed-off Izh43 and killing boar unaware with first shot while looking down barrel. Boar just disappeared and dead body was found 20 meters away in other direction (possibly the direction it could've run).

My totally baseless speculation is that these Schroedingers' animals are both alive and dead. The client detects that they were killed, but the server lets them be alerted and start running. Once they sync up again, the animal is killed and the body falls where it was thought to have run. Just a guess though.

I will look into it. But we killed 2 deers

Me with a Mosin (2nd hit) and everything was right. My friend killed also a deer I'm not sure I think it was the shotgun with 6 shots but I am not sure. He killed the deer with the first shot and everything was okey with that

Hello and thank you for your report survivin.
Unfortunately we haven't been able to reproduce this issue, however, there are certain issues we are aware of which could be causing this issue and they have been scheduled for a fix.
Regards,
Geez