Nephelometric determination of haptoglobin plasma concentrations in fattening pigs

The haptoglobin plasma concentrations in 110 fattening pigs living on three commercial farms and in 28 animals on the university pilot farm were measured using a nephelometric detection method based on an immunoassay. Following calibration of the automated analyser (Nephelometer BN 100) with a human haptoglobin standard, the measurements were performed using anti-human antiserum from rabbits. Differences in age, gender or breed of apparently healthy animals seem to have no influence on the plasma concentration of the protein. The average plasma level of haptoglobin in animals suffering from acute respiratory diseases was significantly higher. Furthermore, an increase was observed in animals without clinical symptoms living on a farm characterized by obvious defects in housing conditions. Comparison studies of the nephelometric method by use of a human or porcine standard for calibration and different anti-human or anti-porcine antisera with radial immunodiffusion as a reference method resulted in high correlation coefficients for all variations. Optimal accuracy was obtained by calibrating the analyser with a porcine standard. Haptoglobin determinations have been shown to be a useful tool for health monitoring during the integrated pig-production process, allowing recognition of performance-reducing conditions. The immunonephelometric determination method is suitable for quantifying porcine plasma haptoglobin for routine checks. The use of animal-specific standards for calibration improves the accuracy of this method.