Advances in porcine salivaomics: A review of biomarkers, diagnostics, and research approaches

Salivaomics, the comprehensive analysis of saliva using omics technologies, has emerged as a noninvasive approach for monitoring physiological and pathological states in pigs. Porcine saliva contains a wide range of biomolecules, including hormones, proteins, nucleic acids, and metabolites, that reflect systemic health, immune activity, and stress status. Compared to blood and other body fluids, saliva collection offers practical advantages, such as stress-free sampling, repeatability, and suitability for large-scale farm applications. Recent studies have demonstrated the diagnostic value of salivary biomarkers, including cortisol and oxytocin for assessing stress; haptoglobin and adenosine deaminase for assessing immune responses; and nucleic acid detection of pathogens such as porcine reproductive and respiratory syndrome virus (PRRSV), porcine epidemic diarrhea virus (PEDV), and Streptococcus suis for disease diagnosis. Advances in proteomics and metabolomics have established saliva as a reliable matrix for assessing welfare and productivity, whereas emerging transcriptomic and microbiomic approaches promise deeper insights into host responses and oral-systemic interactions. Future research integrating multi-omics analyses and optimized sampling protocols will enable the precise real-time health monitoring of porcine populations. Saliva represents a key frontier for improving animal welfare, disease prevention, and sustainable livestock management.