0116 Associations of hygiene and lying behavior with the risk of elevated somatic cell count and lameness
Notice bibliographique
Résumé
The objective of this study was to identify how cow-level factors and housing management affect the risk of elevated SCC (eSCC) and lameness in lactating dairy cows. Cows from six commercial free-stall dairy herds in Ontario, Canada, were enrolled in a longitudinal study. Ten Holstein cows/herd were randomly selected based on days in milk (DIM; <120 d), absence of mastitis treatment in the last 3 mo, and somatic cell count (SCC < 100,000 cells/mL). Data on SCC were collected through DHI testing (∼5 wk intervals). The study began within 7 d after a DHI-milk test, continued until three tests were completed (∼105d), for a total of three observation periods/cow. Elevated SCC was used to indicate subclinical mastitis. An incident of eSCC was defined as a cow having a SCC > 200,000 cells/mL at the end of a period when SCC was <100,000 cells/mL at the beginning of that period. Lying behavior was recorded for 6 d after each milk sampling using data loggers. On d 1 of each recording period, a trained observer scored cows for lameness (5-point numerical rating scale, NRS ≥ 3 = lame). Hygiene scoring (four-point scale), also done by a trained observer, occurred on each visit. Cows were categorized as clean (1, 2) or dirty (3, 4). Stall cleanliness was assessed with a 1 m2 metal grid, containing 88 squares, centered between stall partitions of every 10th stall, and then counting the squares containing visible urine and/or fecal matter. Data were analyzed using multivariable logistic regression models. Cows averaged (mean ± SD) 627 ± 107.7min/d lying, 9 ± 2.8 lying bouts/d, and 72 ± 19.9 min/bout. Over the study period, 13 eSCC were detected, resulting in an incidence rate of 0.73 eSCC/cow-year at risk. The risk of experiencing an eSCC increased 1.4× (P < 0.01) with every 20,000 cells/mL SCC increment at the beginning of the study. Mean proportion of soiled squares/stall was 27%. Each SD (18.8%) increment in proportion of dirty squares/stall was associated with lameness (NRS ≥ 3; OR = 1.5; P = 0.05) and increased the odds of having a dirty udder (DU; OR = 2.4; P = 0.02). Each SD (108min/d) increment in lying time/d increased the risk of having dirty upper legs and flank (DULF; OR = 2.1; P < 0.01), and tended to increase the risk of having a DU (OR = 1.44; P < 0.08). For each 9.6% increase above mean (100%) cow/stall stocking density, the risk of having DULF increased by 1.7× (P = 0.03). These results indicate that lower stocking density and management practices that improved stall hygiene and should be encouraged to reduce the risk of poor hygiene and clinical lameness in dairy cows housed in free-stall barns.
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 machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,001 |
| 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 | 0,000 |
| Communication savante | 0,001 | 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) | 0,004 | 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 source (Gemma direct ou Codex distillé), 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 ».