Abstract
Fibrinogen is an ancient protein found in all vertebrates.1 It is a useful analyte because levels tend to correlate with systemic inflammation.2 As an acute phase protein, levels increase demonstrably in the first five days of an inflammatory response. However, levels may remain elevated with chronic inflammation. Fibrinogen has not been well-studied in birds,3 but in preliminary investigations of rehabilitated seabirds, fibrinogen was inversely correlated with post-release survival.4 Quantitative measurement of fibrinogen in birds requires at least 0.5 ml of plasma, which must be immediately frozen. A methodology that would require smaller volumes and not necessitate immediate freezing for transport would be valuable in a rehabilitation setting, where small birds are common and an in-house laboratory is not available. The Abaxis VSpro, a point-of-care analyzer, was evaluated using a fibrinogen cartridge with blood from birds commonly seen in rehabilitation centers: brown pelicans (Pelecanus occidentalis) and African penguins (Spheniscus demersus). In addition, using penguins, a commercial human fibrinogen sandwich ELISA kita was evaluated. This study also estimated fibrinogen by performing protein electrophoresis on plasma and serum by calculating the difference in the beta fractions. Despite reporting values within the expected range, results from the VSpro were not correlated with values from the reference laboratory. The ELISA kit produced results much lower than expected values and were uncorrelated with reference values. Similarly, the estimated values were not correlated with reference values. Therefore, more research is needed to develop a low-volume, convenient, reliable methodology for determining avian fibrinogen.
Endnotes
aGenway Human Fibrinogen ELISA test kit
Literature Cited
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2. Ganheim C, Hulten C, Carlsson U, Kindahl H, Niskanen R, Waller KP. The acute phase response in calves experimentally infected with BVD and/or Mannheimia haemolytica. J Vet Med. 2003;B50:183–190.
3. Hawkey C, Hart MG. An analysis of the incidence of hyperfibrinogenaemia in birds with bacterial infections. Av Pathol. 1988;17:427–432.
4. Newman SH, Golightly RT, Craig EN, Carter HR, Kreuder C. The effects of petroleum exposure and rehabilitation on post-release survival, behavior, and blood health indices. Final report. Oiled Wildlife Care Network, Wildlife Health Center, School of Veterinary Medicine, University of California, Davis, CA. 2004:1–46.