The effects of antimicrobial growth promoters on intestinal immune and physiological function in two animal models
Bibliographic record
Abstract
A growth promoters are characterized by the addition of low-level, sub-therapeutic concentrations of antimicrobials in animal feed to increase the growth and performance of livestock animals; a strategy that has been successfully used for decades. Unfortunately, the use of these products has led to an increase in numbers of antimicrobial resistant pathogens within the environment and a subsequent ban on the administration of antimicrobials to enhance livestock growth in Europe and also recently in North America. Although it is generally believed that sub-therapeutic concentrations of antimicrobials enhance growth by affecting the intestinal microbiota (microbiota modulation hypotheses), research has shown the antimicrobials have anti-inflammatory properties and at low concentration, these antimicrobials may improve intestinal physiological-inflammatory processes (physiologic inflammation hypotheses) and subsequent performance. The effects of sub-therapeutic levels of two commonly used anti-microbial growth promoter (chlortetracycline and tylosin) on inflammatory responses, immune function and physiological responses were investigated in two animal model studies. Mouse model: C57BL/6J mice treated with chlortetracycline demonstrated that chlortetracycline enhanced growth, induced changes in T cell helper responses and attenuated intestinal inflammation. Swine model: Landrace-Duroc commercial pigs were treated with either chlortetracycline or tylosin and preliminary results demonstrated these antimicrobial growth promoters improved the intestinal epithelial barrier, altered mucous and antimicrobial peptide production and improved meat quality. Collectively, these results demonstrate that sub-therapeutic administration of antimicrobials effect intestinal inflammatory responses and intestinal immune and physiological function.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 0.002 |
| 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".