Pregnancy-Associated Glycoprotein Detection for Cattle Early Pregnancy Screening
The Sekbio Bovine PAG Rapid Test Card is a colloidal gold lateral flow immunoassay for qualitative detection of Pregnancy-Associated Glycoproteins (PAG) in bovine serum — enabling early, non-invasive pregnancy diagnosis in dairy and beef cattle from ≥28 days post-breeding.
PAG is produced exclusively by binucleate trophoblast cells of the bovine placenta, making it a highly specific marker for active pregnancy. The test was independently verified by the Chinese Academy of Inspection and Quarantine using three production batches, achieving 97.5% sensitivity, 96.9% specificity, and 97.3% overall accuracy across 219 clinical serum samples.
Testing commissioned to the Chinese Academy of Inspection and Quarantine (Report No. SEKBIO20231218). Three production batches evaluated against ELISA reference method (DG29® kit) on 219 serum samples from Beijing Dairy Centre.
| Sample Status | Test Positive | Test Negative | Total |
|---|---|---|---|
| Pregnant (ELISA confirmed) | 118 | 3 | 121 |
| Non-pregnant (ELISA confirmed) | 3 | 95 | 98 |
| Total | 121 | 98 | 219 |
| Sensitivity: 118/121 = 97.5% | Specificity: 95/98 = 96.9% | Overall accuracy: 213/219 = 97.3% | |||
Each concentration level tested 60 times per batch (20/batch × 3 batches). LOD confirmed at 2.0 ng/mL with 100% detection rate across all three production batches.
| PAG Concentration (ng/mL) | Batch 230422 | Batch 231026 | Batch 231214 |
|---|---|---|---|
| 1.0 | 0% (0/20) | 0% (0/20) | 0% (0/20) |
| 1.4 | 15% (3/20) | 10% (2/20) | 20% (4/20) |
| 1.6 | 75% (15/20) | 75% (15/20) | 80% (16/20) |
| 1.8 | 90% (18/20) | 95% (19/20) | 95% (19/20) |
| 2.0 (LOD) | 100% (20/20) | 100% (20/20) | 100% (20/20) |
| 4.0 – 14.0 | 100% (20/20) | 100% (20/20) | 100% (20/20) |
| LOD = 2.0 ng/mL (100% detection across all 3 batches). Samples from cows with ≥28 days post-breeding and ≥90 days post-calving. | |||
Early pregnancy confirmation from day 28 post-breeding enables rapid rebreeding of open cows — reducing calving interval and improving herd reproductive efficiency in dairy operations.
On-farm, non-invasive serum-based testing eliminates the need for rectal palpation or ultrasound equipment for pregnancy diagnosis in beef cow-calf operations.
PAG remains elevated with active placentation — falling rapidly with embryonic death. Serial testing enables early detection of pregnancy loss for timely rebreeding intervention.
Anti-bovine PAG antibody pair and colloidal gold test card available as OEM raw materials. Independently validated performance data supports regulatory submissions in key markets.
Common questions about bovine PAG detection, test performance, and OEM supply of anti-PAG antibody pairs for IVD kit development.
Pregnancy-Associated Glycoproteins (PAGs) are a family of proteins secreted exclusively by binucleate cells of the bovine placenta into maternal blood. A PAG cow pregnancy test detects circulating PAG in a blood sample using anti-bovine-PAG monoclonal antibodies in a lateral flow assay (LFA) format. The Sekbio colloidal gold test strip produces a visible result in 15 minutes with LOD 2.0 ng/mL — no laboratory equipment required.
The Sekbio bovine cow pregnancy test detects PAG from approximately day 28 post-conception, earlier than rectal palpation (typically day 35–42). In our validation study, all samples were collected from cows with ≥28 days post-breeding and ≥90 days post-calving to avoid residual PAG interference from the previous pregnancy.
In an independent clinical validation (Chinese Academy of Inspection and Quarantine, Report No. SEKBIO20231218) using n=219 bovine blood samples: 97.5% sensitivity, 96.9% specificity, 97.3% overall accuracy vs. ELISA reference (DG29®). Lot-to-lot reproducibility confirmed across 3 production batches.
PAG cow pregnancy testing is non-invasive (blood draw vs. manual rectal palpation), requires no specialist operator or ultrasound machine, and enables high-throughput herd screening. Ultrasound remains preferred for fetal age estimation and twin detection. PAG testing is best positioned for large-scale pregnancy/open-cow sorting — the Sekbio test demonstrated 97.3% accuracy vs. ultrasound reference.
Yes. The anti-bovine-PAG monoclonal antibodies in the Sekbio cow pregnancy test recognise conserved PAG epitopes shared across bovine PAG family members (PAG-1, PAG-2 and related isoforms). The assay has been validated with samples from dairy breeds (Holstein-Friesian) and beef breeds. Cross-reactivity with ovine PAG is minimal, making the test cattle-specific.
Yes. Sekbio offers the anti-bovine-PAG monoclonal antibody pair (capture + detection clones) used in the validated rapid test as OEM raw material — including colloidal gold conjugation-ready formats. IVD manufacturers can build their own branded bovine cow pregnancy test kits using independently validated components. MOQ 1 mg; bulk supply under ISO 13485-certified QMS. Contact info@sekbio.com for antibody pair data packages.
Full technical specifications, performance data, and OEM pricing available on request.