Tamed Wolves do not growl when attacking mobs/players

The Bug:

While aggressive toward mobs or players, tamed wolves used to growl. However, at a time I can't pinpoint off the top of my head, they stopped doing so. I'd like to say around 1.6 or 1.7, but I'm not 100% sure.

I looked at release notes and on the Minecraft wiki and saw nothing specifically mentioning "-removed tamed wolves growling" or something of the nature. As such I can only assume it's a bug; wolf growling has always been very glitchy in the past.

Steps to reproduce:

1. Tame a wolf

2. Have the dog attack something it can fight

3. It will not growl, just bark. Contrast this with wild wolves attacking something, which do growl.

 

Screenshots added; subtitles show the noises being made