Considerations for managing Mastomys in a captive colony

Mastomys rodents are an uncommon but very useful animal model for biomedical research. Owing to their size, Mastomys can be kept, handled and studied using many of the common practices and equipment that are used with typical laboratory rodents; however Mastomys also have many behavioral and physiological qualities that require special consideration. The Yale Animal Resources Center (New Haven, CT) has successfully maintained a colony of Matomys coucha for 15 years, and based on this experience, Jodi Scholz and Steven Wilson have assembled an overview of this genus and its use in research, with specific recommendations for housing and use of this particular rodent model in laboratory research applications.

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Addressing genitourinary blockage and preventing recurrence in breeding mice

In published literature and among several animal housing institutions in Spain, a condition has been identified in which male mice develop an obstructing bulge in the preputial area that prevents them from successfully breeding. This condition has been found with mice of a C57BL/6J genetic background, and can cause mortality if left untreated. The bulge is generally a buildup of a solid blocking substance within the prepuce that displaces the penis cranially. Over the course of nearly two years, María Jesús Molina-Cimadevila and colleagues studied cases of this condition to characterize it and explore possible treatments to restore the breeding ability of afflicted mice. They analyzed the blocking substance, whose composition suggests that it originates from ejaculate, and they developed a technique for surgical intervention that prevented the condition from recurring and allowed males to successfully breed again. This treatment is only successful if the blocking substance has not already invaded the urethra, but in many cases it is a viable and potentially preferable way to recover fertility in valuable breeding animals without resorting to artificial reproductive techniques.

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