Performance of ad libitum fed dairy calves weaned using fixed and individual methods
Bibliographic record
Abstract
The increasing availability of automated milk dispensers on dairy farms facilitates ad libitum milk supply but weaning calves from high milk allowances is challenging. This study evaluated effects of gradual weaning methods on starter intake, growth, selected blood parameters and weaning distress in ad libitum fed dairy calves during weaning and early post-weaning periods. Thirty-six male Holstein (n = 30) or crossbred (n = 6) calves were individually housed from days 2 to 14 of age and had ad libitum access to milk replacer (MR) from teat buckets. From days 15 to 84 of age, calves were grouped and had ad libitum access to MR, starter, straw and water from automated feeders. At day 35, calves were blocked (age and breed), and randomly assigned to a weaning method: (1) linear fixed (LIN), MR supply was stepped down to 6 l/day on day 36, and linearly reduced between days 36 to 63 from 6 to 2 l/day. (2) Step-down (STEP), MR supply was stepped down to 6 l/day from days 36 to 48, 4 l/day from days 49 to 56 and 2 l/day from days 57 to 63. (3) Dynamic (DYN), at day 36, MR supply was reduced for each individual calf to 75% of the average voluntary consumption between day 29 and 35, then maintained for 9 days, reduced to 50% for 10 days, and to 25% for 9 days. The DYN calves received more MR during weaning than LIN calves, whereas STEP calves had intermediate MR intake. Starter intake was not affected by weaning method. The DYN calves (1.33±0.08 kg/day) grew faster and were heavier than STEP calves (1.10±0.08 kg/day) during post-weaning period, whereas no difference was observed between LIN calves (1.23±0.08 kg/day) and others. At days 70 and 84, concentrations of β-hydroxybutyric acid were higher in LIN calves compared to STEP and DYN calves. Hair cortisol concentrations were not affected by weaning method. During the gradual weaning process CP intake seemed to recovered earlier than metabolizable energy (ME) intake in all treatments, suggesting that ME rather than CP could be the first limiting factor for growth during weaning. These results highlight the post-weaning benefits of DYN and LIN weaning methods when compared with more abrupt step-down strategies.
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 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 | 0.000 | 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) | 0.000 | 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".