BLV Testing

Bovine Leukosis (BLV)

  • Blood-borne viral infection with no effective vaccine
  • Negatively impacts production, longevity, and cull value
  • Utilize ELISA analyses and strategic pooling to reduce testing costs
  • Screen cows by ELISA then submit samples from BLV-positive cows for AntelBio™️ STRATA-G™️ BLV PCR testing
    • The AntelBio™️ STRATA-G™️ BLV PCR test can identify susceptible cows that have become “Super Shedders,” causing the most risk to uninfected herdmates and youngstock.
Leukosis page

Sample Types

  • Milk, individual or bulk tank (fresh, frozen or preserved)
  • Serum (ELISA)
  • Whole Blood (AntelBio™️ STRATA-G™️ BLV PCR or ELISA)


  • Test milk at dry-off or freshening
  • Test serum by ELISA on animals over 4 months
  • Test whole blood by AntelBio™️ STRATA-G™️ BLV PCR at any age
  • Understand your herd’s risk with a BLV Herd Profile. To establish prevalence, test milk samples (DHI or hand-stripped) of the 10-most-recently-fresh cows in the first, second, third and fourth and greater lactation groups.


  • ELISA results available within 5 business days of sample receipt
    • Reported as Positive, Negative or Suspect
    • Suspect ELISA results should be retested
  • AntelBio™️ STRATA-G™️ BLV PCR results available within 10 business days of sample receipt
    • Reported as High, Moderate, Low, or Undetected with a numeric value indicating the number of BLV copies per white blood cell.
Milk Samples:

  • Animals that are within 7 days of freshening have a high probability of giving false positive results when tested because of the presence of colostral antibodies.
  • A suspect result for the Milk ELISA may indicate carryover from a previous Leukosis positive cow in the milking string and should be retested with a hand-stripped sample.
Test Type Positive Negative Suspect
Milk ELISA >0.3 <0.1 0.1 – 0.3
Bulk Milk ELISA >0.1 <0.1
Blood ELISA >1.0 <0.5 0.5 – 1.0


  • Individual ELISA (milk, blood) $6.50/sample
    • Multiple test discount! $11 for two ELISAs on same sample; $15.00 for 3 ELISAs
  • Individual AntelBio™️ STRATA-G™️ BLV PCR $12/sample
  • Group ELISA (pooled or bulk milk) $20/sample
  • Testing billed upon sample receipt
  • $10 sample submission fee per order

Submit Samples

Testing Supplies

CentralStar’s laboratories provide sample analyses on milk, blood, fecal, and tissue samples for a variety of production, disease and health-related traits. More than 6 million samples are processed annually using state-of-the-art equipment and techniques including infrared spectroscopy, flow cytometry, ELISA, PCR, and more.

Diagnostic tests are intended to identify diseases for animal health, and do not determine the “safety” of milk. 

Note: The SS1 qPCR BLV test has been renamed, the AntelBio™️ STRATA-G™️ BLV PCR.