People reading/commenting seem to be misreading the 500 number. Note it's comparing to the previous number 80mg, it's not '500 pills' or '500 tablets' it is 500mg.
Which is consistent with the remaining text and known literature.
Which is consistent with the remaining text and known literature.
(At least that is my reading of the poorly worded sentence)
Tyenol's own research suggests an LD50 for dogs of around 1180–1450mg/kg. In other words, you'd only need around 30,000mg to probably kill a medium sized dog within a short time period, which is about 375 "bait doses". Needless to say, they can "get into trouble" on smaller doses. The manufacturer considers less than 100 "bait doses" to be an "acute overdose" for an adult human.
Sure, the number of poisoned mice a dog would have to eat to suffer even mild liver poisoning is still far in excess of the number of mice a dog is likely to eat, so the implicit point that this isn't likely to poison local large mammals still stands. That doesn't excuse the lack of care in reporting those medical statistics on the part of the author/editor, however.
Someone linked to a video of this story, and if you watch it the original quote was very clearly bait doses.