BVD antigen ELISA is used to detect BVD virus in individual animals. On the ELISA test, a numerical optical density value, called S-N (sample value minus negative control value) is created. Transiently infected (TI) animals have S-N values of < 1.2 and PIs have S-N values > 2. Reporting shows weak positive (S-N <1.2), positive (S-N 1.2-2), and high positive (S-N >2) results against individual animal results. A weak positive result can be taken to indicate an animal is TI while a high positive result indicates the animal is PI. A positive result could be TI or PI so retesting is indicated. Values are proportionately lower in skin samples. Pooling is not possible with antigen ELISA testing.
See also Bovine Viral Diarrhoea (BVD) Testing Guidelines.
Species:
Bovine
Specimen:
Serum (10 ml)
Skin sample (3 mm diameter minimum)
Container:
Serum or gel tube (serum)
Sterile plain pot (skin)
Collection protocol:
Standard venepuncture
Skin – punch biopsy from ear
Special handling/shipping requirements:
Ship chilled