Clinical Trials of a Test Kit for the Visual Diagnosis of Uterine Diseases in Cows

Аннотация

Background and Aim. The prevalence of uterine diseases in cows is reported to range from 14.3% to 50% of obstetric and gynecologic disorders, compromising reproductive function and increasing economic losses. Clinical diagnosis is most informative in the early postpartum period, whereas laboratory methods, despite high specificity, are often impractical for routine on-farm use. This study aimed to develop a test kit for visual diagnosis of uterine diseases in cows and to determine its diagnostic performance.

Materials and Methods. The study was performed on a commercial dairy farm («En-Dala» LLP) in Holstein-Friesian cows (n=100) in their first or second lactation. The design features of the test kit for visual diagnosis of uterine diseases in cows (catheter length, catheter diameter) were determined using a comparative approach. The performance of clinical methods (rectal and vaginal examinations), laboratory methods (Whiteside test and cytology), and two prototype reagents included in the visual test kit was evaluated by calculating sensitivity, specificity, diagnostic accuracy, PPV, and NPV. The diagnostic parameters of the test (foam formation, discoloration time) were determined using descriptive statistics and a comparative method.

Results. An optimal catheter length of 40 cm and diameter of 0.6 cm were established, and a 50-mL syringe with appropriate design features was selected for aspiration of cervicovaginal mucus (CVM). Prototype 1 (10% H₂O₂ + 0.01% methylene blue) showed the most favorable diagnostic profile (Sens. 90.3%, Spec. 100.0%, Acc. 94.2%, PPV 100.0%, NPV 87.5%) versus the other methods, maintaining maximal specificity regardless of days in milk. Diagnostic criteria for test use were defined as foam formation >1 cm and discoloration within ≤4 min, with stratification by clinical course.

Conclusion. The developed test kit for visual diagnosis of uterine diseases in cows is a rapid and highly specific diagnostic method, enabling its use for screening the herd for uterine disease regardless of the days in milk.