204 Evaluation of the Chemical Composition and Animal Performance of Intermediate Wheatgrass (<i>Thinopyrum intermedium</i>) Regrowth for Potential Fall Grazing of Beef Cattle
Notice bibliographique
Résumé
Abstract This study assessed forage yield and chemical composition, feed intake, and performance of beef heifers grazing intermediate wheatgrass (IWG) regrowth post-grain harvest compared with a stockpiled grass/legume control in the late fall. Pastures were established in 2020 at Glenlea, MB, Canada and treatments were: 1) Courtenay tall fescue/Algonquin alfalfa/Oxley II cicer milkvetch (50:25:25; FORCON); 2) IWG, pure stand, no fertilizer post establishment (NFERT); 3) IWG, pure stand+50 kg N· ha-1 post-grain harvest (FERT); 4) IWG with Alsike clover (50:50; AL). The FORCON and IWG treatments were harvested in June (hay) and August (grain) 2021, respectively. Thirty-two beef heifers were assigned to eight paddocks, four heifers per paddock in a randomized complete block design with two blocks. Each block had four paddocks, each paddock receiving one of the four treatments. Heifers began grazing on Oct 6 for a 14-d adaptation period and a 22-d experimental period. Forage samples were obtained once every 2 weeks and analyzed for CP and TDN. Individual feed intake was estimated using the titanium oxide method with fecal samples collected on d 21 and 22 and pooled. Bodyweight and blood samples (blood urea nitrogen, BUN) were obtained on d 1 and d 22. Data were analyzed using a mixed model in R studio, with the fixed effect of forage treatment and the random effects of block and paddock. Forage yield and CP were greater for FORCON (3,515 kg· ha-1 and 14.9% DM, respectively) than the IWG treatments (mean 2778 kg· ha-1 and 12.83% DM, respectively), which did not differ (P &lt; 0.0001 and P = 0.150, respectively). The TDN was less for FORCON (60.6% DM) than IWG treatments (mean 61.5% DM), which did not differ (P = 0.394). Dry matter, CP and TDN intake were lower for FORCON (7.91 kg· DM d-1, 1.15 kg· DM d-1, 4.98 kg· DM d-1, respectively) than IWG treatments (mean 8.54 kg· DM d-1, 1.16 kg· DM d-1, 5.44 kg DM d-1), which did not differ (P = 0.237, P = 0.218, P = 0.137, respectively). The ADG was less for FORCON (0.53 kg· d-1) than IWG treatments (mean 0.77 kg· d-1), with the greatest gains observed in IWG AL (0.90 kg d-1; P = 0.046). Blood urea nitrogen was greater for FORCON (3.95 mmol· L-1) than IWG treatments (mean 3.78 mmol· L-1), which did not differ (P = 0.203) on d 1. However, on d 22 the opposite response was observed with decreased BUN in FORCON (2.97 mmol ·L-1) than in IWG treatments (mean 3.51 mmol· L-1), which did not differ (P = 0.350). In conclusion, IWG offered comparable performance as a feed alternative to the conventional perennial grass/legume mix commonly used for extended grazing. However, the effects of fertilizer or legume on IWG may differ under different soil conditions due to high fertility at the experimental site.
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 | 0,002 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,001 |
| 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 ».