Take steps to make calf vaccination effective
Dr. Mark van der List, professional services veterinarian with Boehringer Ingelheim Vetmedica Inc., says preventing disease in growing heifers isn't a one-shot process. Many vaccines do not prevent disease, but instead prime the calf to provide some level of protection or reduce disease. Also, activities around vaccination time, the environment and nutrition all play a role.
In a recent Dairy Calf and Heifer Association webinar, "Heifer Health at a Forgotten Age," van der List detailed common ways that vaccination efforts go off track, especially for recently weaned heifers being primed for breeding.
Some of the most common reasons vaccination can be hindered include:
--The wrong vaccine (inadequate antigen coverage). Choose a vaccine that offers protection against all economically and regionally significant diseases, as recommended by your veterinarian.
--Improper handling. Expired vaccines, or those that are stored or handled improperly, won't give you the results you want. Read and follow all label instructions.
--No booster. Killed vaccines and some modified-live vaccines require a booster vaccination to achieve adequate protection. The booster should be given according to label directions prior to the time of expected challenge. Immunity wanes with time and so booster vaccines are needed at later times in the heifer's life. Visit with your veterinarian to discuss proper timing of vaccinations.
--Colostral antibody interference. The antibodies absorbed from colostrum, which are so important to early calf health, cannot distinguish between the antigens of a natural challenge and the antigens in a vaccine. Therefore, colostral antibodies can interfere with the immune response to vaccination.
--Inadequate nutrition. Make sure diets satisfy all nutritional requirements to keep heifers healthy. Vaccines should be administered according to label directions to healthy individuals, so read the labels.
--Parasites. Parasites can compromise the health of growing heifers. Here again, vaccines should be given to healthy animals and according to label directions.
--The challenge was too great. If significant disease is already present or encountered, vaccination should not be the only disease management tool used to stop the disease. Vaccines are not a substitute for poor management.
--Stress. Any event that pushes a heifer out of her comfort zone, such as weaning or dehorning, causes stress, which can interfere with a heifer's ability to respond successfully to vaccination. Remember that each small stress is cumulative.
To get the best results from vaccinating, van der List urges producers to minimize challenges and stress and maximize protection. Heifer environment, nutrition and much more all play a role in successful vaccination.
For more information about ensuring the health of growing heifers, watch the complete DCHA webinar, "Heifer Health at a Forgotten Age," presented by Dr. Mark van der List, and sponsored by Boehringer Ingelheim Vetmedica Inc.
To review DCHA's recommendations on vaccinations guidelines for heifers, six months to freshening, see Gold Standards II. Gold Standards III also provides vaccination and health management protocols.