Anyone else have strange vote downs?

The up and down voting just serves as a way for the community to track what answers they find particularly helpful and which they find might be detrimental. One or two down votes aren't unusual if you're commenting a lot. If the overall response to your posts is positive, I wouldn't worry about it.

I'm not sure about the cat question, as I don't see how your advice could be harmful to the situation. In the dog bite case, I'd hazard it's because of the Cesar Millan reference. He has some really good advice at times, such as focusing on adequate exercise and establishing clear and consistent rules, but his focus on dominance theory (which has been long since discredited) makes him a poor example for those with limited knowledge on dog behavior, body language, and learning. He purposefully puts dogs into very stressful situations which significantly increases the chance of a bite (and causes the dogs completely unnecessary stress). Essentially, there's a reason his shows all begin with a "don't try this at home" disclaimer.