Cages are sanitized with hot water and non-toxic disinfectant or detergent, then thoroughly rinsed. Water bottles and food dishes should be cleaned disinfected daily. Breeding Mice and Rats Sex determination is the first step to breeding success. Fortunately, mice and rats are fairly easy to sex. Neonatal male rodents can be distinguished from females by a greater anogenital distance.
Males have a one and a half to two times greater distance between the anal and urogenital openings.
Sexually mature male rodents also exhibit a prominent scrotum. Females can be identified by their prominent bilateral rows of nipples. Sexually mature mice and rats need to be properly paired to avoid fighting and permit successful mating. Adult male mice often fight when caged together, especially in the presence of females. Therefore, a single male mouse should be housed with one or more mature females.