There are two general categories of vaccines—live products and killed products. Modified live IBR, BVD, PI3 and Bangs are examples of live products. These are quite sensitive to light, disinfectants, and heat, so do not use chemical disinfectants in syringes or needles. Boil them. Do not reconstitute these vaccines more than 1 hour before use. Protect them from sunlight. Keep them cool. Killed vaccine examples are blackleg, malignant edema, redwater, enterotoxemia, black disease, and leptospirosis. These are less sensitive, and you can use chemical disinfectants in your needles and syringes. The vaccines should be kept cool, however, and should be protected from sunlight.
Vaccines give longer immunity than serums or antitoxins but usually do not protect until about 2 week after administration. Live vaccines sometimes give better and longer-lasting immunity than killed products. Serums or antitoxins protect for only about 2 weeks, but do protect as soon as administered.
When using modified-live IBR and BVD vaccines, give them separately (2 weeks apart) to prevent calves from getting sick from the vaccine. (ML-BVD vaccine may be an extra hazard in previously BVD-exposed herds.) Killed vaccines give different lengths of immunity. Some, such as redwater, need to be repeated each 6 months or more often in severely infected areas. Others need to be repeated each year. Follow the directions and consult your veterinarian on the length of immunity. No vaccine is 100 percent effective. Effectiveness depends on such things as age of the animal, passive immunity the animal possesses when vaccinated, the stress on the animal, diseases, and other factors we don’t understand. Vaccines against some diseases are more effective than others.
When you work out your program, remember to keep records. If you depend on memory, you will make too many mistakes. Good records are well worth the time and expense.
Source: Dr. Stuart D. Lincoln, Veterinary Science Department, Caine Veterinary Teaching & Research Center, Caldwell, Idaho