According to the Cambridge Grammar of English, not at all. It is wholly standard.
You’re welcome Haihao 
If you need help with Russian, PM me.
Ochen Harasho! 
Should one just let things go so easily?
I asked Ralf a question about his use of “who”, above. You can see his reply. I also said, in my way, that the question had not been answered adequately. I still believe that. Such questioning and personal opinions are normal in these fora/ums - we all add something when we feel there’s more to add. This time, I get rude comments from Ralf about my attempts to a)understand his usage and b) attempt to answer the question more adequately. Why was Ralf so rude? He’s the first moderator here I’ve seen be so rude.
And even if Ralf were right to use his moderator’s hammer above, need he have done it so rudely and unprofessionally?
Now you’ve deleted/edited your comment, fine. Makes it easier to look victimised. Canny.
That’s cheating, mate.
Cheating may be asking members not to ask you questions about your usage and using your moderator’s badge to do it.
Do you wish me to repost what I deleted?
I couldn’t care less.
Really?
Dogs and cats are often treated by their owners as part of the family, so many refer to their pets using who/he/she/whose/her/his. My Molly actually is still a female – a real bitch, hehe – and her welfare is important to us, so she is a she. If someone referred to Molly as an “it”, I’d turn red and Freda would smack the offender and/or throw him out.
Molly, sensing our distress (if not the slight of being called “it”), would bark and growl.
Uhm… what about the context in my original sentence?
“pack”: a pack is a group of animalslike dogs or wolves who live together
I personall think the use of “he/she” for animals and things is usually not very applicable in definition of words, is it? 
Hi Nessie,
I think MrP gave a very good description
For me, “who” just gives a feeling of closeness. It brings us closer to the wolves, but the wolves remain as animals.
The wolf who wanted to eat the girl. It works in certain contexts. In Hansel and Gretel, to name but one.
What works in certain contexts?
Or in Little Red Riding Hood; where the wolf dresses up as a human female.
MrP
OOps, that’s actually the one I meant 
But was the wolf in that story ever really a wolf, in the mind of the writer?
In this case it’d be more a case of an expression marked by a deliberate contrast between apparent and intended meaning.
I don’t see why not. Some very strange creatures have been known to dress up as human females.
But you might do better to consult Peter and Iona Opie; possibly also Bruno Bettelheim, who had an intimate relationship with the tale in question.
MrP
What would, Ralf? What is that post in reply to?