Effect of Pooling and Freeze-Thaw Processes on the PRRSV RNA Detection in TOSc Samples
Simple Summary
Abstract
1. Introduction
2. Materials and Methods
2.1. Study Design
2.2. Sample Collection
2.3. Diagnostic Testing
2.4. Sample Size Justification
2.5. Statistical Analysis
3. Results
3.1. Ct Value Changes per Dilution Level for Each Category
3.2. Changes of Probability of PRRSV RNA Detection After Different Levels of Dilution for Each Ct Value Category
3.3. Comparison of Probability of PRRSV RNA Detection and Difference in Ct Values Between Non-Freeze-Thaw and Freeze-Thaw Groups
4. Discussion
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
Abbreviations
PRRSV | Porcine reproductive and respiratory syndrome virus |
TOSc | Tonsil oral scrubbing |
References
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Dilution Level | Undiluted | 1:3 | 1:5 | 1:8 | 1:10 |
---|---|---|---|---|---|
Category A (29 < Ct ≤ 32) | 30.6 | 32.0 (1.4) | 33.2(2.6) | 33.0 (2.4) | 33.4 (2.8) |
Category B (32 < Ct ≤ 35) | 33.9 | 35.5 (1.6) | 36.1 (2.2) | 36.8 (2.9) | 37.5 (3.6) |
Category C (35 < Ct ≤ 38) | 36.3 | 38.1 (1.8) | 38.9 (2.6) | 39.3 (3.0) | 39.4 (3.1) |
Pooling Level | Mean (95% Confidence Interval) | ||
---|---|---|---|
Category A: 29 < Ct < 32 | Category B: 32 < Ct < 35 | Category C: 35 < Ct < 38 | |
Undiluted | 0.99 (0.77–1.00) a | 0.99 (0.84–1.00) a | 0.97 (0.81–0.99) c |
1:3 | 0.99 (0.77–1.00) a | 0.99 (0.84–1.00) a | 0.71 (0.51–0.86) b |
1:5 | 0.99 (0.77–1.00) a | 0.99 (0.84–1.00) a | 0.66 (0.46–0.83) ab |
1:8 | 0.99 (0.77–1.00) a | 0.94 (0.80–0.99) a | 0.43 (0.25–0.63) ab |
1:10 | 0.99 (0.77–1.00) a | 0.85 (0.69–0.94) a | 0.38 (0.21–0.58) a |
Dilution Level | Non-Freeze-Thaw | Freeze-Thaw |
---|---|---|
Probability of detection with 95% CI | 0.32 (0.23–0.43%) a | 0.28 (0.15–0.46) a |
Difference in Ct values in paired samples | Δ = 0.24 * |
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Li, P.; Osemeke, O.H.; Tran Pham Tien, T.; Wang, C.-Y.; Supple, A.; Almeida, M.N.; Linhares, D.C.L. Effect of Pooling and Freeze-Thaw Processes on the PRRSV RNA Detection in TOSc Samples. Vet. Sci. 2025, 12, 607. https://doi.org/10.3390/vetsci12070607
Li P, Osemeke OH, Tran Pham Tien T, Wang C-Y, Supple A, Almeida MN, Linhares DCL. Effect of Pooling and Freeze-Thaw Processes on the PRRSV RNA Detection in TOSc Samples. Veterinary Sciences. 2025; 12(7):607. https://doi.org/10.3390/vetsci12070607
Chicago/Turabian StyleLi, Peng, Onyekachukwu H. Osemeke, Thinh Tran Pham Tien, Ching-Yang Wang, Angie Supple, Marcelo N. Almeida, and Daniel C. L. Linhares. 2025. "Effect of Pooling and Freeze-Thaw Processes on the PRRSV RNA Detection in TOSc Samples" Veterinary Sciences 12, no. 7: 607. https://doi.org/10.3390/vetsci12070607
APA StyleLi, P., Osemeke, O. H., Tran Pham Tien, T., Wang, C.-Y., Supple, A., Almeida, M. N., & Linhares, D. C. L. (2025). Effect of Pooling and Freeze-Thaw Processes on the PRRSV RNA Detection in TOSc Samples. Veterinary Sciences, 12(7), 607. https://doi.org/10.3390/vetsci12070607