Optimum timing for assessing phenotypic resistance against gastrointestinal nematodes in Pelibuey ewes
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| Dec 31, 2023
| Dec 31, 2023
About this article
Published Online: Dec 31, 2023
Page range: 348 - 356
Received: Jan 25, 2023
Accepted: Oct 27, 2023
DOI: https://doi.org/10.2478/helm-2023-0038
Keywords
© 2023 C. V. Zaragoza-Vera et al., published by Sciendo
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
Fig. 1.
Sensitivity, specificity, predictive positive and negative values, the proportion of positive and false, accuracy and J of Youden (concordance) of Pelibuey ewes classified susceptible or resistant against GIN during early, mid and late pregnancy and lactation periods.
| Variable | Pregnancy | Lactation | ||||
|---|---|---|---|---|---|---|
| Early | Mid | Late | Early | Mid | Late | |
| Sensitivity (Se) | 100 % | 100 % | 100 % | 100 % | 94.4 % | 72.2 % |
| Specificity (Sp) | 31.0 % | 75.9 % | 79.3 % | 100 % | 100 % | 100 % |
| Predictive Positive Value | 47.4 % | 72.0 % | 75.0 % | 100 % | 100 % | 100 % |
| Predictive Negative Value | 100 % | 100 % | 100 % | 100 % | 96.7 % | 85.3 % |
| Proportion of false positive | 69.0 % | 24.1 % | 20.7 % | 0 % | 0.0 % | 0 % |
| Proportion of false negative | 0 % | 0 % | 0 % | 0 % | 5.6 % | 27.8 % |
| Accuracy | 57.4 % | 85.1 % | 87.2 % | 100 % | 97.9 % | 89.4 % |
| Youden's J | 0.3 | 0.8 | 0.8 | 1.0 | 0.9 | 0.7 |
Predictive variables studied to identify resistance against GIN in pregnant and lactating Pelibuey ewes naturally infected during grazing under humid tropic conditions.
| Reproductive stage | Weeks | N | FEC | PCV % | PEC cell 103/μl | PP g/dL | IgA % | BCS | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Mean | SE | Mean | SE | Mean | SE | Mean | SE | Mean | SE | Mean | SE | |||
| Gestation | Early | 47 | 32.0 | 25.1 c | 30.2 | 0.6 b | 0.021 | 0.001 d | - | - | - | - | 3.1 | 0.1 a |
| Mid | 166.9 | 71.4 c | 34.2 | 0.7 a | 0.023 | 0.001 d | 7.00 | 0.08 a | - | - | 3.0 | 0.0 ab | ||
| Late | 518.0 | 139.8 b | 29.0 | 0.5 bc | 0.428 | 0.033 c | 6.86 | 0.07 a | 10.4 | 1.1 b | 3.0 | 0.0 ab | ||
| Lactation | Early | 47 | 1572.8 | 386.6 a | 27.9 | 0.6 cd | 0.538 | 0.043 c | 6.57 | 0.08 b | 10.6 | 1.8 b | 3.0 | 0.0 ab |
| Mid | 650.1 | 253.2 b | 26.4 | 0.7 de | 0.776 | 0.054 b | 6.59 | 0.08 b | 18.0 | 2.3 a | 2.9 | 0.1 b | ||
| Late | 322.5 | 201.8 c | 25.5 | 0.6 c | 0.990 | 0.066 a | 6.37 | 0.08 b | 14.7 | 2.4 a | 2.7 | 0.1 c | ||
Predictive variables to classify Pelibuey ewes resistant against GIN according to the type of lambing under natural conditions of humid tropic of Mexico.
| Variables | Single (n=20) | Double (n=27) | ||||
|---|---|---|---|---|---|---|
| N | Mean | SE | N | Mean | SE | |
| FEC | 117 | 331 | 68 b | 161 | 605 | 95 a |
| PCV % | 30.3 | 0.4 a | 28.0 | 0.4 b | ||
| PEC cell 103/μl | 0.491 | 0.045 a | 0.437 | 0.035 a | ||
| PP g/dL | 6.78 | 0.05 a | 6.59 | 0.05 b | ||
| IgA % | 15.2 | 1.4 a | 12.0 | 1.0 a | ||
| BCS | 3.0 | 0.0 a | 3.0 | 0.0 a | ||