Bad bunny bathroom behavior

Question
My mini lop, Lucy, has recently (within the last few weeks) changed her bathroom habits.  She use to be very good about using her litter box and now I would guess that only 50% is in the litter box and the rest all over her cage.  Because it has been such a drastic change I've grown concerned.  I had changed her litter to Yesterday's News not long ago and thought that she could have been opposed to this so I've changed back to Carefresh with no change in behavior. I haven't found that this behavior carries over to the rest of our home, only in her cage where she spends most of her time (when we aren't home and at night).  Which is a change for her because until 3 weeks ago I was home with her nearly everyday for 6 months.  She stills gets out for hours a day but recently it is usually with my partner instead of myself. In the interest of giving you all the information that may be important I would like to mention that she is 5 years old, spayed, eats a diet of high fiber grass hay, no pellets (she was weaned off of them a couple months ago), and fresh greens.  She has gradually become less active (but by no means inactive) in the past couple months as well.  Her fecal pellets are normal consistency and urine a normal pale yellow.  She almost always eats her cecotropes.  She is also nearing the end of a big shed.  I am a vet tech working at a animal hospital specializing in felines and canines and could easily bring her in to check her urine, do blood work, etc. but really would like to determine if this is at all a medical problem (or an angry bun problem). Any help would be much appreciated.  

Thanks,
Riki

Answer
Dear Lucy,

From your description, this doesn't sound as much like a health problem as much as an anxiety problem.  She may be acting out because she sees less of you, though rabbits mostly nap during the day and don't seem to be in as much need of cuddling.  If your absence has resulted in her getting less attention, though, I'd suspect she's upset by that change.

Poor box habits can also be due to urinary tract infection:

www.bio.miami.edu/hare/urinary.html

or joint pain causing her to avoid hopping into the box.  If she's suffering from a bit of arthritis or other pain, that could contribute to the messy box habits.

It wouldn't be a bad idea to get her to a good rabbit vet:

www.rabbit.org/vets

for a full wellness exam.  If you want to save money by doing some of the tests yourself at the clinic where you work, then it would still be a good idea to have a good rabbit vet with whom to consult if any of the values are amiss.

I hope this helps!

Dana