I have a large c&c cage housing my girls...they have never had a fallout before ..but this morning i noticed one of them has a gash across her back..She was busy eating so didnt seem upset but nothing in there to cause this only one of other girls. I havnt spent a lot of time with them recently as ive had an op & finding it difficult getting down to play then ive got to get back up ! Any ideas..The pen is about 5 x 3 & it houses 5 girls.