Should a booster vaccination for parvovirus be given to sows, and if so, when?

The appropriate time to administer a booster vaccination for parvovirus to sows is during the weaning period, which aligns with the correct answer. Vaccinating sows at weaning helps to enhance their immunity and prepare them for future breeding, ensuring they can pass on adequate protection to their piglets through colostrum.

There are specific reasons why the timing of the booster is critical. Weaning is a stressful period for both sows and piglets, and immunization during this time helps in building a stronger immune response that aids in protecting the piglets from contracting diseases as they transition to solid food and acclimate to new living conditions.

Additionally, other options do not align with the best practices for vaccination protocol. Administering a booster vaccination at birth is inappropriate since newborns typically rely on maternal antibodies to protect them until they are older and more capable of responding to vaccinations. Similarly, waiting until three months after birth would miss the critical early window when sows can influence their offspring's immunity, and it is essential to establish protective measures as early as possible to ensure the health of both sows and piglets. Thus, vaccinating sows at weaning is the recommended course of action for maintaining herd immunity.