What is cross-fostering?

• A. Mating animals of different strains
• B. Placing pups with a female that did not give birth to them
• C. Having more than one female in the cage with the pups
• D. Having more than one male in the cage with the pups

Answer: (B)

Cross-fostering is moving newborn pups to a dam other than the one that gave birth to them. This is done to separate genetic or litter-specific factors from the influence of the maternal environment, or to improve survival when the biological dam cannot care for the pups. It’s typically performed soon after birth so the foster dam will accept and nurse the pups, and the foster dam should have adequate milk and a receptive temperament. After placement, the pups are monitored to ensure they feed, stay warm, and grow appropriately, and records are kept to track their origin and care. This approach is distinct from simply breeding animals together or housing multiple dams and pups, and it is a common method used to study maternal effects and to rescue or balance litters.