Turkey Reoviral Arthritis/Tenosynovitis - Part 2

By Rob Porter DVM, PhD, Sunil Mor, DVM, PhD, and Sagar Goyal, DVM, PhD
University of Minnesota
This is the 2nd of a 4 part series.

Has the presentation of TARV remained the same?

Grossly, most legs have periarticular fibrosis and edema without gastrocnemius tendon rupture; however, there is also edema of the shank accompanied by rupture or laxity of one or more of the digital flexor tendons (Figure 1). In the last two years a greater percentage of the TARV cases are complicated by bacterial infections e.g., Escherichia coli, Ornithobacterium rhinotracheale, Pasteurella multocida and Staphylococcus aureus. In some of the hock joints, one might also observe marked erosion of the articular cartilage of the tibiotarsus (drumstick).

Figure 1. Sixteen-week-old tom turkey that was positive for reovirus infection. In some instances the lameness is associated with swelling of the shank with complete or partial rupture of one or more digital flexor tendons (arrow).

Characteristics of TARV

The TARV can survive in conventional house litter for over one week and survives in non-sterile drinking water for over two weeks. However, the virus is highly susceptible to the following disinfectants (Table 1) with all tested disinfectants inactivating > 4 log10 TCID50 TARV within 10 min contact time.

Disinfectant	Category	Recommended dilution
Virocid	Quaternary ammonium +aldehyde	1:256
Keno X5	Oxidizing agent	1:400
Synergize	Quaternary ammonium +aldehyde	1:200
One Stroke	Phenol	1:250
Tek Trol	Phenol	1:200

Table 1. Five disinfectants listed above have been shown to inactivate >4 log10 TCID50 of TARV in <10 minutes of contact time.

What is new in diagnostic test development?

With partial financial support from the Minnesota Turkey Research and Promotion Council, we are developing cross-neutralization assays. We have raised hyperimmune sera against several TARV strains to prepare a serum panel for test development. The development of a turkey-specific ELISA test for screening of turkey flocks is also in progress.

Diagnosis at the Minnesota Veterinary Diagnostic Laboratory

Cost for leg necropsy is $75 plus 10.00 accession fee on Minnesota cases.Real-time PCR is now available at the Minnesota Veterinary Diagnostic Laboratory and is combined with virus isolation for a total fee of $115.00.

What should I send the veterinary diagnostic laboratory if I suspect turkey reoviral arthritis?

1. In lieu of whole birds, select six fresh, not frozen, turkey legs excised at the hip joint (acetabulum)

2. Pack on ice or frozen gel packs and ship overnight in Styrofoam cooler.

The funding for this research came from the Rapid Agricultural Response Fund of the University of Minnesota and Minnesota Turkey Research and Promotion Council.

For more information, please contact:  Dr. Rob Porter, Minnesota Veterinary Diagnostic Laboratory (612) 624-7400 or by email porte349@umn.edu or Dr. Sunil Mor, Minnesota Veterinary Diagnostic Laboratory (612) 624-3698 or by email kumars@umn.edu.