How safe any of the treats are depends on the way your dog chews them and the way they are cured.
Dogs who chomp off big chunks of any rawhide type treat and swallow them whole can run into trouble. Treats manufactured in other countries sometimes have toxic levels of pesticides on them.
Over all bully sticks other than being a bit smelly can be a good chew treat if your dog doesn't try to swallow them whole.
I buy a lot of the treats my dogs get off this site
http://www.petextras.com/
And the dogs have approved of them all. I like it that this company looks for sources free from salmonella contamination in their pig ears and looks for high quality sources for treats.
Hope this helps you!
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