An Investigation of the Effect of Transport Duration on Weaned Piglet Welfare
Notice bibliographique
Résumé
This thesis reports the welfare impact of transport duration on weaned piglets as assessed using physiological and behavioural measures, the characterization of the trailer compartment environment during long transport, and the evaluation of the physiological impact of weaning. \nThrough the enrollment of two commercial farm operations, a prospective cohort study was conducted and assessed multiple indicators of piglet welfare following exposure to long (>30h) or short (<3h) transport during Canadian summer months. Representative of the North American swine industry, the two operations differed in their protocols for time between weaning and transport; long transported piglets were weaned days before transport and short transported piglets were weaned on the day of transport. Marked physiological compromise was not evident in piglets following exposure to either transport duration; an association between in-transit mortality and transport duration was not observed. However, long transport was associated with increased weight loss and decreased hydration, while short transport was associated with increased muscle fatigue and elevated stress response. Differences in the motivation between duration groups to feed, drink, and rest after transport were apparent; long duration piglets were more likely to feed and drink on arrival, while short duration piglets were more likely to be observed lying down following transport. These behavioural and postural differences appear to be related to both weaning- and transport-associated practices. Examination of focal trailer compartment environments during long duration transport showed that passive ventilation allows for large fluctuations in compartment temperatures outside the thermoneutral zone for newly weaned piglets, even during summer months. Differences in piglet lying and standing during transport between compartments was observed and may be due to differences in the physical environment and subsequent effects on animal comfort. \nFinally, evaluation of the relative contribution of weaning to the stress response and injury observed after transport demonstrated that weaning-associated stress and lesions remain detectable for at least 72 hours after weaning. It would be prudent to explore how the amount of time between weaning- and transport-related procedures impact piglet welfare in more detail as time between weaning and transport vary among North American swine operations.
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 | 0,001 | 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 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,002 | 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 ».