PSVIII-9 Effects of growth implants and timing of vaccination on calf immunity and growth performance
Bibliographic record
Abstract
Abstract This study assessed calf growth performance and blood parameters of beef calves under different growth implants and timing of vaccination protocols. Crossbreed beef calves (n = 59) were stratified by birth body weight (BW) and age (41 ± 5.2 kg of BW and 70 ± 8 d of age) and randomly assigned in a split-plot design with implant strategy as the main plot and timing of vaccination as the subplot. The main plot (treatment) consisted of 3 implant strategies: 1) Synovex C (SC; n = 20; 100 mg progesterone/10 mg estradiol benzoate, or 2) Synovex One Grower (SG; n = 19; 150 mg trenbolone acetate and 21 mg estradiol benzoate; or 3) no implant (CON; n = 20). Subplot treatments were the timing of vaccination booster against bovine respiratory disease pathogens on 1) weaning (WV; n = 29) or 2) 7-d post-weaning (PWV; n = 30). Cow-calf pairs were treated alike in a single pasture during the pre-weaning phase, receiving the same vaccine (Bovi-Shield Gold One Shot and Ultrabac 7) on d 0 (implantation day) and booster time (WV or PWV). After weaning (approximately 187 d of age), calves were allocated in a single pen receiving ad libitum hay until d 60 post-weaning. Body weight and blood were collected on d 0, weaning, d 0 and 28 relative to vaccination booster, and d 60 post-weaning. Blood was collected to determine insulin-like growth factor (IGF-1), cortisol, and leptin concentrations and to perform a complete blood cell count. WV calves had decreased cortisol concentrations on booster day and 28 d post-vaccine (P = 0.01). Regardless of implant treatment, calves tended to have decreased IGF-1 concentrations 28-d post-vaccine booster (P = 0.09). An effect of treatment (P < 0.01) was detected for lymphocyte counts, with CON having greater concentrations vs. SG and SC calves. A treatment × timing of vaccination (P < 0.01) interaction was detected for monocyte counts, where SG-PWV calves had the greatest concentrations. A treatment effect (P < 0.02) was observed for eosinophil percentage, where SG had reduced percentages than CON, while SC was intermediate. An effect of treatment was detected for leptin (P < 0.01), with SG calves having the least, CON being intermediate, and SC the greatest concentrations. From d 0 to 60 d post-weaning, SG tended to have greater ADG (P ≤ 0.07) compared with CON, while SC was intermediate. On d 28 and d 35 post-weaning, calves implanted with SG were heavier (P ≤ 0.04) than the CON but not than SC. In summary, this study demonstrates that growth implants and timing of vaccination significantly affect both physiological parameters and growth performance in beef calves. Implanting calves with Synovex One Grower resulted in improved growth performance.
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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 | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| 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) | 0.001 | 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".