Which of the following statements is NOT true about mouse parvovirus?

• A. It cannot be eliminated from a colony by cessation of breeding.
• B. It causes bloody diarrhea, depression and dehydration in adult mice.
• C. Embryo derivation is the preferred method of eliminating the virus from a colony.
• D. It is often present in the animal's tissues as a latent infection.

Answer: (B)

Mouse parvovirus typically causes little to no illness in healthy adult mice. In adults, the infection is often subclinical or only very mild, and overt gastrointestinal disease like bloody diarrhea with depression and dehydration is not a common or expected presentation. When disease does occur, it’s usually in very young mice or in animals with compromised immune systems, not in standard adult colonies. The virus tends to persist and can be latent in tissues, so it can be present without obvious signs. For this reason, stopping breeding alone doesn’t reliably clear the virus from a colony. Re-derivation by embryo transfer using virus-free recipients is the preferred method to eliminate MPV from a colony, because it bypasses the infected dam and maternal environment. In summary, the statement about bloody diarrhea and dehydration in adult mice does not fit how MPV typically presents, while the other points—persistence in tissues and the value of embryo transfer for elimination—align with its biology and control.