Update on ruminant testing at AHL

Davor Okjic, Jim Fairles

Animal Health Laboratory, University of Guelph, Guelph, ON    

AHL Newsletter 2022;26(1):10

Recently, AHL Virology has realigned ruminant testing and added some new tests:

1. Bovine viral diarrhea virus/bovine adenovirus/bovine coronavirus – test code: bvdadco

This triplex test combines bovine viral diarrhea virus (BVDV) PCR, bovine coronavirus (BCoV) PCR, and a new test, bovine adenovirus (BAdV) PCR.  The BAdV PCR cross-reacts with multiple BAdV types and will detect BAdV 1,2,3,4,5,6,7 and 8.

Note 1: The triplex BVDV/BAdV/BCoV PCR will now be routinely used when BVDV testing is requested.  If BVDV PCR only is required, e.g., for export or surveillance purposes, please indicate on the submission form that the purpose of BVDV testing is export/surveillance and we will test samples with a BVDV-only PCR test.

Note 2: The triplex BVDV/BAdV/BCoV PCR can be used for investigation of respiratory and/or enteric diseases.

Note 3: When BVDV/BAdV/BCoV PCR yields a positive BVDV result, BVDV typing can be done at an additional cost, upon request.

2. Bovine adenovirus sequencing – test code: badvseq

When BVDV/BAdV/BCoV PCR yields a positive BAdV result, the sample can be further genotyped/classified by adenovirus hexon gene sequencing at an additional cost, if desired.

3. Malignant catarrhal fever (MCF – ovine herpesvirus-2) PCR – test code: mcfpcr

Samples with a constellation of clinical and histologic findings that were consistent with malignant catarrhal fever were used for PCR validation.  MCF PCR results and histologic findings were in 100% agreement.

The Bovine rotavirus/corona virus PCR remains unchanged (Rotavirus/coronavirus, bovine/equine - PCR.  Includes: coronavirus - PCR, rotavirus Group A and B – PCR – test code: rocopcr).  Because rotavirus infection is not significant in respiratory cases, this test will now only be used in enteric case testing including the Bovine enteric panel (Bovine neonatal enteric panel – test code: bentpnl).

The Bovine comprehensive respiratory panel (Comprehensive bovine respiratory disease panel – test code: brsppnl) has now changed to reflect the testing changes described above.  It will now include:

  • Bovine viral diarrhea virus/bovine adenovirus/bovine coronavirus PCR – bvdadco
  • Bovine respiratory virus panel PCR (BoHV-1/IBR, BPiV-3, BRSV) - brvp3
  • Bacterial culture, food/fiber producing animals (other than swine) – cultf
  • Mycoplasma bovis PCR – mbpcr

Sampling and submission guidelines remain the same: 2 deep nasopharyngeal samples need to be included for the test – 1 for PCR (swab in virus transport media or red top tube with 0.5 mL of saline) and 1 for culture (bacterial culture swab).  If pooling is requested, the panel will be split into the individual tests, as pooling can be done only for the virology PCR tests.  Pooling is not recommended for bacterial culture since a nasopharyngeal swab is considered a highly contaminated sample.  There is now one less test in this panel, and the price has been reduced accordingly.

Pooling is available for all PCR testing.  Please note: when pooling is requested, a pooling charge is added per sample to cover the labour and consumables needed for pooling.

The ruminant submission form is being updated to reflect these changes.   AHL