Mice and Rats

Most people lump mice and rats together. It even sounds right together - miceandrats. Ratsandmice. They're both rodents. They look similar. Tons of people can't tell them apart. When I was a kid I was told the difference was in the tail - mice had furry tails and rats had scaly ones.

by Suprise Truck

But mice and rats do NOT go together.  No, rats prey on mice.  Here, let me share a different story before I get to the good stuff I just found out.


I answer questions on AllExperts under the mouse category, and the majority of the questions I get are really, painfully silly.  I'm very near to just sitting down and making a website with all of the repetitive answers:

• My mouse is sneezing/coughing/chirping!  What do I do?
• Why is my mouse itchy and scabby?
• What's this bump on my mouse?
• I "rescued" an orphan mouse, what do I do now?
• My mouse died!!  Omgwtfbbq?
• Why doesn't my male mouse get along with my other male mouse?
• I in one way or another completely fucked up trying to breed the mice I just brought home today from the pet store and now they are dead/dying/sick/aborting/etc.  Fix it!

Now, don't get me wrong, asking questions is GOOD.  I answer them all politely.  If you need to ask me, DO.  I would much rather be mildly annoyed for five minutes because you didn't read the very last question I answered than have your mice suffer because you're worried I'll scoff.  I just wish people would use their noggins about mice, that's all, and consider using a vet or reading over past questions.

But about 20% of the questions I get are really, really good.  I LOVE these questions, even though it doesn't always turn out well for the mice.  It keeps me sharp, makes me learn more, and fine tunes the diagnostic part of my brain.  I love puzzles, and good questions.

One such question was just asked.

I didn't take it seriously at first because it sounded stupid.  It was something along the lines of how their brand new mice had been dying, behaving oddly, etc.  I wasn't getting a very good vibe from the questioner.  Their main inquiry, though, was why mice tend to eat the head/brain of mice that have passed, because one of his was missing half it's skull when he found it.

Initially I had a few, generic, answer-form thoughts.  Hunger.  Don't feed your mice once a day for Christ's sake, they aren't dogs.  They need food available 24-7.  Fighting.  I frequently see mice go for the head when fighting over territory, resources, pecking order, etc.


Wait.  That's bigger than that.  WHY do they go for the head?  Because it's quickest?  Then why would they eat the brain afterwards?

Shit guys, I have no idea.  WHY do mice eat the head?  Is this a war tribe kind of thing?  Are brains delicious?  Is it ensuring they're really dead?  WHY do rodents, not even just mice, start from the head and move down?

So I googled, and I found this:

"Rat odor is stressful to mice and has an effect on their behavior and reproduction. In fact, rat odor is sometimes used as a predator odor to study anxiety and antipredator behavior in mice.

Specifically, domestic and wild-stock mice who are exposed to a conscious or anesthetized rat tend to flee, and if prevented from fleeing, they show defensive or attack behavior (Griebel et al. 1995, Blanchard et al. 1998).

Mice housed in the same room as rats tend to be more stressed than mice housed without rats (Calvo-Torrent et al. 1999). Mice who can smell rat urine take ten times longer to start eating a treat than mice who cannot (Merali et al 2003). Mice who were exposed to rat urine for just a few minutes startle more afterwards, even up to two days after the rat urine exposure (Hebb et al. 2003). Pregnant mice exposed to rat urine produce fewer litters than mice who were not exposed (de Catanzaro 1988)."


Okay, so I totally knew that rats ate mice, and that if you attempted to house them together you'd have one less mouse.  I never thought about the effect of their smell, before.  Up to two days of stress after smelling rat urine?  I used to keep my ratties in the same room as my mice.  I've even placed cages on top of the rat condo while changing them out.  I feel pretty bad for what I was putting the little guys through.  It's useful information for breeding, too!

I feel this is pretty relevant to this, as well.


I don't have an answer for him yet, but I'll figure it out.  It's really bugging me now, though.  Why eat the head?  It appears to be a strong instinct for rats, and from what I've seen of cannibalism in mice, it doesn't look a whole lot different.

In the meantime, I don't think I'm going to be able to eat for hours.  Not a whole lot makes me nauseous, but you should check out the inside of a mouse some time, or watch a momma go batshit and eat her bebbehs.  *shudder*  They DON'T start at the head.  Moms just go for it.

Guh.

-Mouse



P.S. - Same Pet of the Day.  This girl needs a home by Monday, 11 AM.  I pulled some serious strings to keep her alive that long, she was supposed to be put down today.  I can't help it.  I like tripawds.  If anyone can help out, email me at twsquirrels@gmail.com.