Effects of metabolizable energy and lysine restrictions on growth performance, blood profiles, and expression of myostatin and leptin genes in broilers
Bibliographic record
Abstract
To investigate the effects of metabolizable energy and lysine restriction on performance, and gene expression of leptin and myostatin, three hundred twenty day-old Ross broiler chicks were randomly allotted to four treatments. Birds were subjected to their respective diets comprising two levels of ME (3200; 2880 kcal kg-1) and two levels of lysine (1.10; 0.88%) during days 8 to 21. The dietary crude protein levels were reduced with the proportion to the lysine levels, while ratios of essential amino acids relative to lysine were similar for all diets. During restriction, weight gain, breast muscle and abdominal fat yield were lower in birds fed lysine-restricted diets. Relative myostatin mRNA abundance was increased in breast muscle of lysine-restricted birds, while expression of leptin mRNA in abdominal fat was downregulated by energy and lysine restriction. During realimentation, birds previously fed with energy and/or lysine-restricted diets had comparable performance as birds fed unrestricted diets. At day 42, energy and lysine restriction increased relative myostatin mRNA expression in breast muscle and birds previously fed diet restricted in both energy and lysine had the highest relative myostatin mRNA expression (energy × lysine interaction, P < 0.001). The relative leptin mRNA abundance was significantly lower in birds previously fed energy-restricted diets. These results indicated that early energy and lysine restriction from day 8 to 21 exhibited growth compensation during realimentation. In addition, myostatin and leptin mRNA expression in breast muscle and abdominal fat were modulated by nutritional treatments and were closely associated with changes in breast muscle yield and abdominal fat deposition. Key words: Metabolizable energy, lysine, myostatin, leptin, broiler
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 | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 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 | 0.001 |
| 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".