Kinetic of acute-phase proteins in foals – a review

Abstract

Acute phase proteins (APPs) are proteins that form part of the non-specific innate immune system and are increasingly being used in veterinary medicine as a non-specific diagnostic tool. This review is intended to help veterinarians obtain an overview of the data published to date on the diagnostic value of the most important APP in foals. In addition to the current analytical laboratory methods, the various in f lammations and infections in which the various APPs can be helpful as inflammation parameters will be discussed. Serum amyloid A (SAA) is regarded as the only “major” APP in horses and is also playing an increasingly important role in the diagnosis of inflammation in foals. Studies show that SAA, due to its rapid rise (100–1000-fold) and higher sensitivity, should be preferred as an early indicator of inflammation, especially in comparison to fibrinogen. For example, increased SAA values were described for non-specific bacterial infections as well as for specific diseases such as enteritis (SAA: 178.7 ± 99.1 mg/l) or diarrhoea (SAA: 132 ± 143 mg/l). The average SAA concentration of the healthy foals in this study was 19.37 ± 9.41 mg/l. Fibrinogen is the most frequently measured positive APP in equine medicine, as there are simple and quick methods for its determination. In contrast to SAA, fibrinogen is a „moderate “APP and therefore a fibrinogen concentration of 2–4 g/l is fre quent in healthy horses, whereas SAA is extremely low (