Ask the Vet

By Dr. Ken McMillan, Contributing Columnist

READER QUESTION:

In a past issue of Progressive Farmer, you wrote in your column about vaccinating cattle at birth versus later in life. From what I understand, the blackleg vaccination should be given around 4 months of age. If I administer this at birth will I have a better outcome or is there no difference?

DR. MCMILLAN'S ANSWER:

Let me expand on this a little. Most calves from properly vaccinated dams have good maternal immunity to clostridial diseases, with blackleg being the most significant for animals at 3 to 4 months of age.

In an ideal world, with controlled calving seasons, calves should be vaccinated around that 4-month time period with a clostridial vaccine, as well as for infectious bovine rhinotracheitis (IBR), bovine viral diarrhea (BVD), parainfluenza virus (PI3) and bovine respiratory syncytial virus (BRSV). They also should be given boosters before weaning. If you cannot prior to weaning, and you have your hands on that newborn calf, there is nothing wrong with a properly administered clostridial vaccine. At worst, the calf won't respond, but some may.

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Editor's Note: Please contact your veterinarian with questions about the health of your herd or other animals. Every operation is unique, and the information in this column does not pertain to all situations. This is not intended as medical advice but is purely for informational purposes. Email Dr. Ken McMillan at vet@dtn.com.

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