It is a sad and unfortunate thing to hear about. And I don't want to make light of, or condone mistreatment of animals which could cause harm or death' particularly is the situations which could have been avoided.
I primarily just wanted to add perspective before jumping on a media finger-pointing frenzy. For instance, I have seen this story being used as the sole reasons to boycotting The Hobbit, which in my opinion are too extreme, but to each their own. I have no intentions of watching the films in theaters, but this is based off a long line of news about the films and the apparent disregard for trying to even remain remotely faithful to Tolkien's story. I would still not be calling for any boycott or shutting down of the films, I mean they're made and if people want to see them, that's their choice, I choose to wait for I have no driving need to watch in theaters.
The perspective being, hundreds of animals were used in the films, I can see it being enough that no harm or mistreatment was caused during the filming parts. There appears to be a gap in the oversight of animal treatment in films. However, from what I've seen it sounds like the proper authorities were alerted to possible issues in the housing of the animals. And the steps were taken by the film-makers (or should it be producers?) to comply with solving the issues.
Maybe the 27 deaths were avoidable, maybe more could have been done...who knows. But my feelings are, accidents and mistakes happen, and as much as people like to search for where the fault and blame falls, sometimes there is no one at fault. Sometimes it is the people doing the best they can with the information they have and are given at the time.