Production of PRRSV-negative pigs commingled from multiple, vaccinated, serologically stable, PRRSV-positive breeding herds
Bibliographic record
Abstract
Objectives: To determine whether PRRSV-negative pigs could be produced from multiple PRRSV-positive herds and to investigate the serological stability of these herds and the impact of sow vaccination. Methods: Piglets originating from non-vaccinated and vaccinated herds were weaned at 8 to 14 days and housed separately in an off-site nursery for 90 days. Pigs were tested by PRRS IDEXX ELISA at weaning and at 30, 60, and 90 days of age. A subset of pigs was tested using PRRS reverse transcription-polymerase chain reaction (RT-PCR) and restriction fragment length polymorphism (RFLP) assays. Serological stability of breeding herds was assessed by PRRS IDEXX ELISA. Results: The five vaccinated herds were serologically stable. Piglets from these herds became seronegative after weaning and remained PRRSV negative up to 90 days of age. Pigs from two of the five non-vaccinated herds were PRRSV negative. One of these herds was serologically stable. Piglets from the other three non-vaccinated herds were PRRSV positive at weaning, and the number of seropositive piglets and their S:P values increased to 90 days of age. Two of these herds were not serologically stable. After vaccination of open sows and gilts, PRRSV-negative pigs were produced from one of these two herds. Implications: Piglets weaned at 8 to 14 days from multiple, serologically stable sow herds and commingled were PRRSV negative at 90 days of age. Vaccinating gilts twice prior to breeding and sows at weaning may increase the stability of breeding herds. Results must be validated in large commercial operations.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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 source (direct Gemma or distilled Codex), 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".