Choosing porcine ELISA kits now depends less on the marker list and more on the sample you plan to run them on. Across swine research, teams are shifting toward non-invasive matrices — oral fluid and saliva — alongside field-tolerant acute-phase proteins and multi-marker panels, and that shift changes how a porcine ELISA kit should be selected and validated.1,2
Quick takeaways
- Non-invasive matrices (oral fluid/saliva) are increasingly used for herd monitoring and biomarker research.1,2
- Acute-phase proteins are common anchors because they tolerate timing and field variability.3,4
- Matrix validation matters more than ever — saliva and serum are not interchangeable without checks.4
Why swine teams are moving to oral fluid and saliva
Oral fluid collection is non-invasive, scalable, and easier to standardize at pen level than repeated blood draws. Recent work links oral fluid biomarker measurements to herd indicators of health and performance, supporting a growing role in applied settings.1 A 2024 review summarizes how pig salivary analytes are used for health monitoring and disease-related research.2
What is driving the shift
- Lower sampling stress and easier repeat sampling for longitudinal designs.
- Population-level monitoring — one pooled sample can represent a pen or herd.
- More "real-world" signal — oral fluid captures variability that serum-only sampling can miss.
What teams measure in oral fluid and saliva
- Inflammation / health status: acute-phase proteins and S100 proteins (e.g., S100A12).2,5
- Stress physiology: cortisol and other stress-linked analytes (context-dependent).2
- Immune activation: adenosine deaminase (ADA) and myeloperoxidase (MPO), which now have dedicated salivary assays.5,7
Acute-phase proteins: the field-ready readouts
Cytokines remain important, but many swine teams pair them with acute-phase proteins (APPs) that better tolerate timing noise and field variability. ITIH4 — also called porcine major acute-phase protein (Pig-MAP) — is a classic example: a positive APP in pigs with growing saliva and oral-fluid measurement interest.3,4
What this looks like in practice
- APP anchors: Pig-MAP/ITIH4, haptoglobin, serum amyloid A (SAA) and C-reactive protein (CRP), depending on study design and availability.2,3
- Cytokine add-ons: core cytokines such as IL-6, TNF-α, IL-1β and IFN-γ when kinetics matter.
- Why it helps: APPs provide a stable "inflammation context" for interpreting more transient cytokines.
Sample matrix at a glance: serum, plasma, saliva and oral fluid
The single most important decision when selecting porcine ELISA kits is the sample matrix. The same marker can behave very differently in serum versus saliva, so the table below summarizes the practical trade-offs.
| Matrix | Invasiveness | Repeat / pooled sampling | Typical analytes | Key validation caution |
|---|---|---|---|---|
| Serum | High (blood draw) | Limited | APPs, cytokines, hormones — reference matrix | Cleanest signal; still confirm species reactivity |
| Plasma (EDTA / heparin) | High (blood draw) | Limited | Similar to serum | Anticoagulant can interfere with some assays |
| Oral fluid / saliva | Low (non-invasive) | High (pen-level, repeatable) | Pig-MAP/ITIH4, S100A12, MPO, ADA, cortisol, α-amylase | Much lower concentrations; needs saliva-specific validation4,7 |
Table 1. General characteristics of common porcine sample matrices. Analyte behavior and detection limits are marker- and kit-specific — always confirm with the kit's validation data.
Infectious disease and immune monitoring
Oral fluids are widely used for pathogen and antibody monitoring in swine systems, including PRRS surveillance contexts.2,3 On the biomarker side, infection studies show coordinated changes in saliva analytes linked to inflammation, immune activation and tissue damage — reported for Streptococcus suis6 and, more recently, for African swine fever in both domestic pigs and wild boar.8 Antigen reagents such as the recombinant PRRSV nucleoprotein support serology and assay development alongside these workflows.
Welfare and stress physiology
Saliva is increasingly used to probe stress- and welfare-relevant physiology because it can be collected repeatedly with minimal disruption. The 2024 review summarizes stress-linked analytes and practical considerations for salivary monitoring in pigs,2 with cortisol and α-amylase among the most studied readouts.
Emerging molecular readouts
Beyond proteins and enzymes, porcine saliva is being explored for molecular signals — for example, salivary small RNAs (miRNAs) that could connect physiology with the oral microbiome and environment. These approaches are still early-stage, but they expand the non-invasive biomarker toolkit.9
How to choose porcine ELISA kits by marker and matrix
As teams diversify matrices, species + matrix validation becomes the primary selection criterion for porcine ELISA kits. A 2025 PLOS ONE study evaluated commercial ELISA kits for measuring ITIH4 (Pig-MAP) specifically in pig saliva, showing that saliva performance needs its own evidence and cannot be assumed from serum data.4
- Confirm the matrix: serum vs. plasma vs. saliva/oral fluid vs. lysate — and check the kit is validated for it.
- Run a quick dilution series: verify linearity and parallelism before scaling up.
- Plan for field variability: hemolysis, lipemia and handling differences can dominate the signal.
Browse the full ELISA kit range or the veterinary & agricultural research area to match a marker to a validated matrix.
Frequently asked questions
Which biomarkers can be measured in pig saliva or oral fluid?
Validated salivary readouts in pigs include acute-phase proteins (Pig-MAP/ITIH4, haptoglobin), the inflammation marker S100A12, immune enzymes such as myeloperoxidase (MPO) and adenosine deaminase (ADA), plus stress markers like cortisol and α-amylase.2,5,7
Can a porcine serum ELISA kit be used on saliva?
Not automatically. Saliva concentrations are typically much lower than serum, and kit performance must be re-validated for the saliva matrix; a 2025 study showed that only some commercial ITIH4 kits measured pig saliva reliably.4
What is Pig-MAP (ITIH4)?
Pig-MAP (porcine major acute-phase protein) is the inter-alpha-trypsin inhibitor heavy chain 4 (ITIH4), a positive acute-phase protein that rises with inflammation and can be measured in both plasma and saliva.4
Which acute-phase proteins are most used in swine research?
Haptoglobin, Pig-MAP/ITIH4, serum amyloid A (SAA) and C-reactive protein (CRP) are the most commonly measured porcine APPs, often quantified together in multiplex panels.3
How do you validate an ELISA kit for a new sample matrix?
Run precision (intra-/inter-assay CV), accuracy (spike-recovery), and a dilution series to confirm linearity and parallelism in the target matrix before applying the kit to study samples.
References
- Ornelas MAS, et al. Associations between health, productive performance and oral fluid biomarkers in commercial pig farms. Porcine Health Management. 2024;10(1):62. doi:10.1186/s40813-024-00418-1
- Zheng L, et al. Advances in Research on Pig Salivary Analytes: A Window to Reveal Pig Health and Physiological Status. Animals (Basel). 2024;14(3):374. doi:10.3390/ani14030374
- Tor M, et al. Multiplex Assay to Determine Acute Phase Proteins in Modified Live PRRSV Vaccinated Pigs. Journal of Proteome Research. 2024;23(8):3515–3523. doi:10.1021/acs.jproteome.4c00154
- Ortín-Bustillo A, et al. ITIH4 (Pig-MAP) in saliva of pigs: evaluation of two commercially available ELISA kits for its measurement. PLOS ONE. 2025;20(10):e0335133. doi:10.1371/journal.pone.0335133
- Gutiérrez AM, et al. S100A12 protein as a porcine health status biomarker when quantified in saliva samples. The Veterinary Journal. 2024;303:106062. doi:10.1016/j.tvjl.2024.106062
- López-Martínez MJ, et al. Changes in salivary biomarkers of stress, inflammation, redox status, and muscle damage due to Streptococcus suis infection in pigs. BMC Veterinary Research. 2023;19(1):100. doi:10.1186/s12917-023-03650-z
- Botía M, et al. Gaining knowledge about biomarkers of the immune system and inflammation in the saliva of pigs: the case of myeloperoxidase, S100A12, and ITIH4. Research in Veterinary Science. 2023;164:104997. doi:10.1016/j.rvsc.2023.104997
- Carrau T, et al. Changes in saliva and serum analytes in domestic pigs and wild boar experimentally infected with African swine fever virus. Veterinary Research. 2025;56(1):213. doi:10.1186/s13567-025-01598-6
- Jeong GH, Lim KS. Exploring the potential of salivary small RNAs as non-invasive biomarkers in pigs. Journal of Animal Science and Technology. 2025;67(6):1207–1214. doi:10.5187/jast.2025.e17
Note: This article summarizes research trends for R&D (research-use-only) purposes; it is not a clinical or veterinary diagnostic guideline. Source records verified via PubMed.
