Key Points for Quality Evaluation of Veterinary Biological Reagents and Their Application in Animal Disease Surveillance

Application Scope and Common Types of Veterinary Biological Reagents

Veterinary biological reagents are fundamental materials used in animal disease diagnosis, immune effect evaluation, veterinary drug residue screening, and veterinary research. Common types include antigens and antibodies for serological testing, nucleic acid amplification reagents for molecular detection, labeled antibodies for immunochromatography, as well as standard positive sera, negative sera, and reference materials. In the breeding of major economic animals such as pigs, cattle, sheep, and poultry, related reagents are commonly used for etiological or serological surveillance of diseases such as foot-and-mouth disease, highly pathogenic avian influenza, porcine reproductive and respiratory syndrome, and brucellosis. Different animal species and testing purposes impose different requirements on reagents. For example, reagents intended for field screening typically emphasize ease of operation and speed, while reagents used for laboratory confirmation focus more on sensitivity and specificity. Understanding these common types helps user institutions conduct preliminary screening based on actual testing scenarios.

Technical Indicators to Consider in Quality Evaluation

When evaluating veterinary biological reagents, assessments are generally conducted from aspects including appearance, fill volume, sterility or microbial limits, potency, specificity, sensitivity, repeatability, and stability. For diagnostic antigens or antibodies, the product insert typically specifies the dilution range, storage conditions, production date, and expiration date. For molecular biology reagents, attention should be paid to the applicability of the amplification system, the limit of detection, and cross-reactivity. Before introducing a new batch or a new supplier's product, laboratories may conduct parallel comparisons with reference methods or reference materials to observe whether results fall within acceptable ranges. Batch-to-batch consistency should also be monitored, as minor differences between batches of the same item may affect the comparability of long-term surveillance data. It should be emphasized that reagent quality evaluation should be based on comprehensive performance under actual conditions of use, rather than a single result or individual claims in promotional materials.

Common Issues in Storage, Transportation, and Use

Veterinary biological reagents are sensitive to temperature, light, and humidity, and the storage and transportation chain is often a critical factor affecting reagent performance. Reagents generally requiring frozen or refrigerated storage should avoid repeated freeze-thaw cycles. For lyophilized products, the vacuum state of the vial should be checked before opening, and after reconstitution, they should be used within the time specified in the product insert. The cold chain should be maintained throughout transportation, and upon receipt, temperature records, packaging integrity, and accompanying documents should be verified. In grassroots veterinary laboratories, common problems include failure to use up reagents promptly after opening the kit, mixing components from different lot numbers, operating environment temperature deviating from requirements, and inaccurate pipetting volumes. These issues may cause nonspecific reactions, signal weakening, or false-negative results, thereby interfering with the judgment of animal disease surveillance. Therefore, establishing a record system covering acceptance, storage, requisition, and disposal of remaining reagents helps reduce quality fluctuations.

Industry Standards and Procurement Management Recommendations

China implements relatively strict management of veterinary biological products and related diagnostic reagents, and production and distribution processes must comply with corresponding regulations and technical standards. When selecting veterinary biological reagents, procurement institutions generally require suppliers to possess appropriate qualifications, with product labels and instructions being standardized and batch information clearly stated. For important animal disease surveillance projects, comparison data with national standard products or reference materials may be requested, but exaggerated claims in commercial promotion should not be used as the sole basis for procurement decisions. Laboratories should establish standard operating procedures internally, conducting small-scale verification of new reagent batches before putting them into use.

In routine management, it is recommended to focus on the following aspects:

Verify whether the product name, specifications, and storage conditions are consistent with the product insert.

Check cold chain transportation records and packaging integrity upon arrival.

Conduct verification experiments for products being used for the first time or when changing batches.

Retain usage and storage records to facilitate result traceability and anomaly analysis.

Overall, the scientific selection and standardized use of veterinary biological reagents are important guarantees for the quality of animal disease surveillance. Only by integrating technical evaluation, cold chain management, and operational standardization can veterinary biological reagents more effectively fulfill their fundamental role in animal health management.