'STOP! Don't give that to them!'
He looked at me dumbfounded. I often encourage him to feed the leftover salad or his bones to the rats why on earth am I throwing a fit when he was offering them a bit fruit?
'Well, I just remembered that oranges are bad for male rats. '
'Um, I don't remember, something about ummmm, I have no idea? I just know I read it somewhere'
'OKAY, can the girls have it?'
'Do you have enough for ALL of them?'
'For the Chickens it is!' As he marched outside.
Three days later and a lot of research... I now can say exactly why not to feed the boys mangos, oranges, caraway, cherries, dill, lemons, mint and tomatoes. They have high levels of d-limonene which can cause cancer in male rats.
According to an article written by James A. Swenberg, in the Environmental Health Perspectives, male rats have a protein in their kidney called alpha2u-globulin. When a male rat has too much d-limonene, it causes the protein in the kidneys to build up, causing tumors. Overall the rat would need to consume copious amounts of orange juice, or other D-limonene rich foods over the course of several months to cause this cancer. Why not err on the side of caution and just avoid it for the boys.
The females do not have this problem because they do not have the protein in their kidneys. I even read in a Scientific Research Paper that it was shown to lower the mammary tumor growth in the female rat. Crazy Rats!