I have two male guinea pigs both a little over a year old, today I noticed dark orangeish brown urine on the white plastic floor part of their cage where their food bowl is. I wiped it up with a paper towel and it does not look like blood to me. Last night and this morning they had fresh Swiss chard and this vegetable is new for them so I was not sure if that could have caused the color of this urine? Some of the leaves of Swiss chard were dark purple and some were green so I thought maybe it could have came from that. if anyone has any advice or have experienced this from feeding their guinea Swiss chard please comment or let me know because I am concerned.