Hi!
I'm testing your mod, and when I clicked on a baby sheep, a cage appeared above it's head and my server disconnected me.

There was no server crash, the log only tells this:
[07:13:14] [Server thread/INFO]: DcNdrew lost connection: TranslatableComponent{key='disconnect.genericReason', args=[Internal Exception: io.netty.handler.codec.EncoderException: java.lang.NullPointerException], siblings=[], style=Style{hasParent=false, color=null, bold=null, italic=null, underlined=null, obfuscated=null, clickEvent=null, hoverEvent=null}}
[07:13:14] [Server thread/INFO]: DcNdrew left the game

Hi, I am not able to replicate this crash. From my testing, I can put any baby animal in cages just fine. Do you have steps to reliably replicate this problem? Thanks.

Since I have not received any more information on this issue, I am going to assume 5aaf4d9 fixes this issue as well. Reopen if this is not the case.