Even if it was accurate, how do you know Joseph wasn't just joking? Which would make it a completely different context from the other examples you gave.
Joseph approved of killing flies and mosquitoes. They are mutants from hell!
I think the quote you are looking for (at least the one I'm aware of) is about the Elders during the march of Zion's Camp trying to kill a rattler or two in the camp, and Joseph told them not to, that until men lost their bloodlust that the animals wouldn't (severely paraphrased).
As for animals talking, who knows for sure, but I'm looking forward to speaking to my animals afterwards. The dog will have good things to say to me--the cat, I'm not so sure. But then again, I don't expect the cat to attain a kingdom of glory.....
The Kid reacted to Seminarysnoozer in Talking Animals