Nutrient and Energy Utilization in Enzyme-Supplemented Starter and Grower Diets for White Pekin Ducks
Bibliographic record
Abstract
The aim of this study was to determine the effect of enzyme supplementation on energy and nutrient utilization in White Pekin ducks fed starter and grower diets. In each of 2 experiments, 8 ducks were assigned to each starter or grower diet without or with enzyme supplementation at 1 g/kg of diet in a 2 x 2 factorial arrangement of treatments for a 120-h nutrient utilization assay. Starter and grower diets in experiment 1 contained 3.68 and 2.51% N, respectively, and 4.321 and 4.274 kcal/ g of gross energy, respectively. Corresponding values in experiment 2 were 2.93 and 2.89% and 3.994 and 3.930 kcal/g. The enzyme supplement was a cocktail containing 7,500 units of protease and 44 units of cellulase per gram. Endogenous energy losses were from 23 to 44 kcal in the 2 experiments, and endogenous amino acid (AA) losses ranged from 14 mg for Trp to 137 mg for Asp. In experiment 1, a lower energy output of ducks fed the grower diet, coupled with lower N output, resulted in greater (P < 0.05) diet AME(n) for the grower than the starter diet. Apparent digestibilities of all AA were higher (P < 0.05) in the starter diet than in the grower diet regardless of enzyme supplementation, more so for the S-containing AA. Average true digestibility of all AA was 93.7 and 90.4% for the starter and grower diets, respectively. There was no effect of enzyme supplementation of diet on the true digestibility of AA except for Met. Average true digestibility of all AA for diets not supplemented or supplemented with enzyme were 91.3 and 92.8%, respectively. In experiment 2, energy utilization of the grower diet was higher (P < 0.05) than that of the starter diet. Lysine and Asp showed lower (P < 0.05) apparent digestibility in the grower than in the starter diet. Enzyme supplementation of starter or grower diets did not affect the apparent digestibility of AA, except for Met, whose digestibility was increased by 2.4 percentage points in an enzyme-supplemented diet (P < 0.05). Except for Trp, true digestibility of AA was not affected by diet type or enzyme supplementation. The results show that the enzyme cocktail evaluated improved AA and energy utilization in White Pekin ducks and that such an enzyme-related response is diet composition-dependent.
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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 | 0.000 | 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".