American Fancy Rat & Mouse Association

This article is from the WSSF 2013 AFRMA Rat & Mouse Tales news-magazine.

Breeding & Stuff

Aggressive Rats With Orange Patches, Pregnant Rat Stashing Food

By Karen Robbins

QMy parents breed rats. It all started 3 years ago when we bought a male and then a female. We had them separated but then somehow they bred and it went on after that. Most wiped themselves out (dominance and fighting over females). The rats we breed are albino but with creamy patches. Five times so far an orange gene has kicked in and created an albino white with orange patches, but each time they have shown aggression and killed themselves. We don’t know why they have done it. We have one at the moment but she was meant to give birth last week and she did but she is still pregnant with them as last week she only had 2 and part of a miscarriage we guess. She collects up food and hides it constantly, any food, anything laying about that is food—dog food, food off plates, vegetables, seeds, anything. We want to know a bit more about why this is happening but we have no answers. We recently got a Cinnamon male rat that we planned to breed with her but her problems seem to be really bad so we aren’t going to bother till we find out what she is doing and why.

ANot clear on your question. The rat that had 2, are they still alive or were they born dead? You say she was due last week but is still pregnant—that sounds like a vet needs to take a look at her because if she is still pregnant she could have something else going on. Or perhaps her due date was miscalculated.

As far as collecting food, if she has babies, then that sounds normal. Some rats are more pack rats than others. Does she have food in her cage at all times? Mom-rats need a lot more protein and fat ( while pregnant and nursing. What is her normal diet and what is her diet when pregnant (what do you add)?

Can you send photos of the mom in question so we can see what her color and markings are? Would also like to see photos of your white rats with creamy patches to help with their ID.

In regards to fighting, only one male should be in with a small group of females for breeding. Rats showing that much aggression is either from genetics or lack of resources (not enough food and water in the cage at all times for the amount of rats or they are too crowded). How many males/females do you have in each cage? Are they colony bred (females not separated to have their babies)? Even when breeding rats for reptile food, the females should be separated into their own cage so there is no fighting over babies (mice get along much better when it comes to several females raising their kids together in one group). You can read more on aggression in these online articles:

Eva Johansson in Sweden has these articles on temperament:

And the Rat Behavior and Biology web site has these articles:

Updated January 1, 2019