Short-term feed restriction impairs the absorptive function of the reticulo-rumen and total tract barrier function in beef cattle1
Notice bibliographique
Résumé
The objective of this study was to evaluate whether different severities of short-term feed restriction (FR) affect the absorptive function of the reticulo-rumen and total tract barrier function in beef cattle. Eighteen ruminally cannulated and ovariectomized Angus × Hereford heifers were blocked by BW into 3 blocks, with blocks conducted sequentially. Treatments were imposed during the 5-d FR period by restricting heifers to 75 (FR75), 50 (FR50) or 25% (FR25) of the ad libitum feed intake measured during a 5-d baseline period (BASE) occurring immediately before FR. Throughout the study, heifers were housed in individual pens (9 m(2)) and were fed the same diet (60% forage:40% concentrate) with free access to water. Dry matter intake was measured daily and ruminal pH was measured every 2 min throughout the study. Ruminal fluid and blood samples were collected on d 3 of the BASE and FR periods, and the temporarily isolated and washed reticulo-rumen technique was used to evaluate short-chain fatty acid (SCFA) absorption on d 5 of the BASE and FR periods. Total tract barrier function was evaluated starting on d 2 of the BASE and FR periods using a pulse dose of Cr-EDTA followed by 48 h of total urine collection. Data were analyzed using the Proc Mixed procedure of SAS with the fixed effects of block, treatment, period, and the treatment × period interaction, the random effect of cow nested in block with period included as a repeated measure. Dry matter intake did not differ among treatments during BASE but, as imposed by the experimental model, DMI during FR relative to BASE equated to 70, 49, and 25%, which was close to the targeted values of 75, 50, and 25% (treatment × period, P < 0.001). A treatment × period interaction (P < 0.001) was also detected for ruminal SCFA concentration with the concentration decreasing as the severity of FR increased, whereas there were no differences during BASE. Mean ruminal pH increased during FR with increasing severity of FR, but was not different during BASE (treatment × period, P < 0.001). Absorption of SCFA across the reticulo-rumen tended to decrease with increasing severity of FR (P = 0.08). For individual SCFA, acetate absorption (mmol/h) tended (P = 0.057) to be less for FR25 and FR50 when compared with FR75 and decreased (P = 0.05) by almost 70 mmol/h at FR25 and FR50 relative to BASE (322mmol/h). Heifers restricted to 25% (FR25) feed had greater urinary Cr recovery during FR than BASE, whereas no changes were detected for FR75 and FR50. This study indicates that moderate severities of short-term FR decrease the absorptive function of the reticulo-rumen, but more severe FR is required to compromise total tract barrier function in beef cattle.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,001 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,000 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».