Table 4.
Evaluation of Fe, Zn, Co, LDH and ALP as an indicator for diagnosis of subclinical mastitis in riverine buffalo
| Name of the parameter | Total samples examined (N) | Test positive samples (a+b) | Test reaction as compared to cultural examination | Percent sensitivity a/(a+d) ×100 | Percent specificity c/(b+c) ×100 | Percent accuracy (a+c)/N×100 | Positive predictive value (%)a/(a+b) ×100 | Negative predictive value (%)c/(c+d) ×100 | Likelihood ratio (positive) sensitivity/(100-specificity) | Likelihood ration (negative) (100-sensitivity)/specificity | |||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| |||||||||||||
| True positive (a) | False positive (b) | True negative (c) | False negative (d) | ||||||||||
| Fe | 2,048 | 253 | 172 | 81 | 1,471 | 324 | 34.67 | 94.78 | 80.22 | 67.98 | 94.78 | 6.64 | 0.69 |
| Zn | 2,048 | 465 | 372 | 93 | 1,459 | 124 | 75.0 | 94.01 | 89.40 | 80.00 | 92.17 | 12.52 | 0.02 |
| Co | 2,048 | 267 | 152 | 115 | 1,437 | 344 | 30.64 | 92.59 | 77.59 | 56.93 | 80.69 | 4.13 | 0.75 |
| LDH | 2,048 | 287 | 170 | 117 | 1,435 | 326 | 34.27 | 92.46 | 78.37 | 59.23 | 81.49 | 4.55 | 0.71 |
| ALP | 2,048 | 484 | 407 | 77 | 1,475 | 89 | 82.06 | 95.04 | 91.89 | 84.09 | 94.31 | 16.54 | 0.19 |
| Zn+ALP | 2,048 | 497 | 493 | 4 | 1,548 | 3 | 99.20 | 99.74 | 99.65 | 99.19 | 99.81 | 381.54 | 8.02×10−3 |
| Positive bacterial culture and SCC≥2×105 cells/ml | 2,048 | 496 | 496 | - | 1,552 | - | 100 | 100 | 100 | - | - | - | - |