Cow-Calf Herd

Cow-Calf Herd (BVDV-Suspect Herd)

BVD is Suspected (High Risk)

• Poor reproductive performance despite good nutrition and bull fertility

• High calf morbidity / mortality despite good sanitation and nutrition

• Laboratory confirmation of BVDV transient (acute) infection (TI) or BVDV PI animals

Appropriate diagnostic testing to determine

if Persistently Infected (PI) with BVDV

Testing Must Occur Before Start of Breeding Season

• All calves (IHC test is appropriate for calves of all ages)

• All cows without calves (open or calf died) (IHC, Ag-capture ELISA, VI, PCR)

• All replacement bulls and heifers (purchased or raised) (IHC, Ag-Capture ELISA, VI, PCR)

Test Negative

Test Positive

Heifers, Bulls & Cows

• Sell PI animals to slaughter

Safe for human consumption

Test Dams

Test Negative

• Return dam to breeding herd

Test Positive

• Sell to slaughter

Safe for human consumption

• All cows still pregnant at time of testing must be removed from breeding herd because fetus is of unknown BVDV PI status

• Absence of confirmed PI calves does not guarantee absence of BVDV problem. If you are still suspicious, testing the next calf crop is recommended.

• Use IHC (immunohistochemistry), pooled PCR, ELISA of skin samples, or Virus isolation (VI)

• Implement complete vaccination program prior to breeding in replacement animals and appropriate boosters in adults

• Prevent direct contact with cattle of unknown BVDV control status

Retain in herd

• High NPV* of tests

* NPV = negative predictive value, i.e. likelihood that a test negative animal is truly PI negative

Calves

• Remove calf and dam from breeding herd

• If dx with VI or PCR, confirm persistence of virus by retesting in 3 weeks

• Euthanize calf

• Test dam

MUST BE DONE PRIOR TO THE START OF THE BREEDING SEASON