Coat and size of guinea pig

Question
I have 2 male guinea pigs that almost identical brothers and are about 1 year old.  I have recently notice that one of them seems to have decreased in size and has a thinner coat that has gotten lighter in colour.  I have been trying to find some information of what might be causing this.  The larger of them seems to be a bit more agressive and always has been that way but I had no problems until recently.  Should I separate them and see if that helps.  Or is there something else that may be causing this.  I really dont know what to do.  Please help me.

Nancy

Answer
I would separate them, I separate all of my male babies out by 4 months because this is the time when they really start to get their hormones in and fight. His coat could be thinning because the other pig is chewing it, also he could possibly have mites, which would result in hairloss and itching. The most common thing though given your situation would be the other pig chewed some of the hair, which will show the undercoat of the pig which is lighter. I would separate them and see if in a couple of weeks the hair starts to grow back, if it does then you have solved your problem. Let me know if you have any more questions.
Brittany
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