Infectious disease testing

Enabling herd health through effective BVD management

Offering a range of BVD testing options to suit your need, IDEXX can support regular monitoring using bulk milk tank testing to narrowing down a Persistently Infected (PI) animal through PCR or ELISA. Based on recent trial data, farms with a previous or suspected BVD issue are highly recommended to test all calves using IDEXX BVD Antigen ELISA on ear notch1

Why test calves?

The key to the management of BVD is the early identification and removal of PI animals that enter the herd. This means testing should be conducted on all new introductions into the herd, and calves being the most important new introductions to test.

Why use the IDEXX BVD Antigen ELISA on ear notch?

A recent survey conducted revealed that 100% of vets stated that the best test for BVD would identify PIs only2. The IDEXX BVD Antigen ELISA on ear notch will identify PIs as positive and is much less likely than PCR to identify Transiently Infected (TI) animals as positive. This reduces the unnecessary culling of TIs. The 2019 trial in calves under 38 days showed that the IDEXX BVD Antigen ELISA on ear notch identified PIs with 100% sensitivity and specificity. Of calves that tested positive by PCR in the trial, 80% were TI animals and therefore could have been unnecessarily culled.

What’s so special about ear notches?

Ear notches provide the best sample for identifying PIs. Ear notches are robust, are less affected by maternal antibodies, are easy to sample, store and send. 

The 35 day myth

The results of the trial also showed that when using the IDEXX BVD antigen ELISA test on ear notch samples in calves under 38 days of age there is no interference of maternal antibodies.

What were the findings of the trial?

To learn more about effective BVD management, you can access a variety of resources below that cover this trial and its’ findings. You can read the full study, recently reviewed and published in a peer reviewed journal3.

For a full test listing as well as our BVD Farm Framework testing guide please consult your IDEXX Directory of Products and Services.

To connect with a Diagnostic Practice Consultant:

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  1. BVD Technical bulletin written by Dr. Andrew MacPherson
  2. Data on file at IDEXX Laboratories, Inc. Hamilton, New Zealand.
  3. McDougall S. Effect of calf age on bovine viral diarrhea virus tests. Journal of Veterinary Diagnostic Investigation. 2021; doi: 10.1177/1040638721998821