Effect of Supply of Metabolizable Protein on Splanchnic Fluxes of Nutrients and Hormones in Lactating Dairy Cows
Bibliographic record
Abstract
The effect of the supply of metabolizable protein on splanchnic fluxes of nutrients and hormones was measured in six catheterized late-lactation Holstein cows in a crossover design. Two isonitrogenous diets (16.3% CP), but differing in rumen protein degradability and estimated metabolizable protein (MP) supply (1654 g/ d, Lo-MP; 1930 g/d, Hi-MP) were fed, each over a 35-d experimental period. On d 34 or 35, net fluxes of nutrients and hormones across the portal-drained viscera, the liver, and total splanchnic tissues were determined. Portal absorption of total, essential, nonessential, and branched-chain amino acids (AA) increased with the Hi-MP diet. Approximately 76% of the additional metabolizable protein supply was recovered as extra AA-N absorption in the portal vein. Liver removal of AA was not different between diets, and this resulted in a greater net release across the splanchnic tissues for the Hi-MP diet. This extra AA supply provided substrates for the observed increased milk protein yield for the Hi-MP diet. Fractional efficiencies of conversion of absorbed individual essential AA into milk protein ranged from 0.42 to 0.68. The corresponding efficiencies for utilization of postsplanchnic AA supply were 0.42 to 1.80. Provision of methionine, phenylalanine, and histidine beyond the liver were similar to outputs in milk protein but the other essential AA were supplied to peripheral tissues in excess of milk output, indicative of oxidative mechanisms in nonhepatic tissues. Net fluxes of glucose, NH3-N, and urea were not affected by the diets. Neither arterial concentrations of insulin, somatotropin, or IGF-1, nor net transfers across the portal-drained viscera or liver of insulin, were affected by the diets. Although portal release of glucagon was not different between the diets, a smaller proportion was removed by the liver on the Hi-MP diet. Metabolism of AA across the splanchnic tissue bed is a major determinant of the quantity and the profile of AA delivered to peripheral tissues.
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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 | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 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".