Vaccination programs should follow a continuous year-round schedule based on local health problems. Vaccination against rhinopneumonitis should be performed at 5, 7, and 9 mo of gestation. Vaccinations that require annual boosters should be administered 4–6 wk before the mare's due date to stimulate the dam to produce antibodies that will be transferred to the foal via the colostrum (see Management of Reproduction: Horses: Example of Vaccination Schedule for Broodmares). Colostrum should be ingested in the first 24 hr of life to effectively provide passive transfer of immunoglobulins.
Last full review/revision July 2011 by Patricia L. Sertich, MS, VMD, DACT