Equine Rotavirus Vaccine Killed Virus For vaccination of pregnant mares to provide passive transfer of antibodies to foals against equine rotavirus. This product is conditionally licensed by the USDA while additional efficacy and potency data are being developed. DOSE: Pregnant mares, inject one 1 mL dose intramuscularly at the eighth month of pregnancy using aseptic technique. Administer a second 1 mL dose one month later (i.e., at the ninth month of pregnancy). A third 1 mL dose is then given one month later (i.e., at the tenth month of pregnancy). Each pregnancy requires vaccination with 3 doses.