The results reported in this study showed that both saliva and serum samples had higher APP concentrations in PRRS pigs aged 8-9, 17-18 and 24-25 weeks in conventional herds than SPF pigs of the same age (p<0.05). In addition, increases in APP were obtained with age independently of the health status of the animals. According to the ROC analyses performed, saliva could be a better specimen than serum to quantify Hp and CRP levels in field conditions and may contribute to a more efficient detection of diseased animals at farm level.
Gutiérrez AM, Martínez-Subiela S, Soler L, Pallarés FJ, Cerón JJ. Use of saliva for haptoglobin and C-reactive protein quantifications in porcine respiratory and reproductive syndrome affected pigs in field conditions. Vet Immunol Immunopathol. 2009. Vol. 132 (2-4): 218-223.