Efficiency of a genetic test to detect benzimidazole-resistant Haemonchus contortus nematodes on sheep farms in Quebec
Bibliographic record
Abstract
Benzimidazole-based drugs have been used to treat Haemonchus contortus and other gastrointestinal nematode infestations in sheep. However, numerous cases of benzimidazole-resistance in H. contortus have been reported worldwide. The fecal egg count reduction test (FECRT), which consists of comparing parasite egg counts in feces before and after treatment, is a technique commonly used to assess anthelmintic resistance. Unfortunately, this method is not very sensitive and is dependent on factors that can distort the results. Veterinarians and farmers have been seeking a method for detection of anthelmintic resistance which would be faster and cheaper than the FECRT, and used prior to anthelmintic treatment. Mutations called single nucleotide polymorphisms (SNP) on the a-tubulin isotype 1 gene of H. contortus have been associated with benzimidazole resistance. These mutations are located at positions 200 (a TTC codon in susceptible parasites and a TAC codon in resistant ones), 167 (TTC for susceptible parasites and TAC for resistant parasites), and 198 (GAA for susceptible parasites and GCA for resistant parasites). A molecular method that uses pyrosequencing has been developed to measure the frequency of the resistant allele of these three markers of benzimidazole resistance. The female nematode releases eggs, which are shed through the feces of the sheep. We can apply the pyrosequencing protocol on nematode eggs isolated from sheep feces to assess the benzimidazole resistance of the adult nematodes that colonize the host's abomasum.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.003 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".