Influence of housing conditions on responses of pigs to preslaughter treatment and consequences for meat quality

Abstract

. 1999. Influence of housing conditions on responses of pigs to preslaughter treatment and consequences for meat quality. Can. J. Anim. Sci. 79: 285-291. The effects of housing conditions on behavioural and cortisol responses during preslaughter treatment, as well as the consequences for meat quality, were studied in 48 slaughter pigs. Pigs were either raised in intensive housing conditions ("standard" treatment: standard farrowing crates (4.2 m 2 ) followed by standard rearing pens (0.5 m 2 /pig) and fattening pens (0.8 m 2 /pig) or in extensive conditions ("enriched" treatment: larger farrowing pens (7.2 m 2 ) followed by larger rearing and fattening pens (both 1.2 m 2 /pig), all provided with straw).No differences in behaviour during transport or in any of the meat quality variables were found between treatments. During preslaughter handling, stockmen needed significantly less time to load pigs from standard housing conditions (standard: 56.8 ± 11.9 s; enriched: 93.7 ± 12.5 s). Standard pigs may have been more motivated to leave their pens in order to explore another environment than pigs from the enriched housing pens. Rise in salivary cortisol levels due to transport (standard: 6.68 ± 0.80 ng mL -1 ; enriched: 3.63 ± 0.58 ng mL -1 ) was difficult to interpret as omission of straw during the hours prior to transport apparently led to high baseline cortisol levels in enriched pigs (8.63 ± 1.27 ng mL -1 vs. 2.60 ± 0.37 ng mL -1 in standard pigs). The extensive housing system should be preferred as it is known to have positive effects on pig welfare, and does not lead to impaired meat quality. On ne relevait aucune différence de comportement en cours de transport ni parmi les variables de qualité de la viande entre les deux régimes de logement. Durant les manipulations préabattage, les préposés prenaient significativement moins de temps pour charger les porcs produits en conditions de logement standards, soit 56,8 ± 11,9 s contre 93,7 ± 12,5 s pour les porcs élevés dans le régime enrichi. Les porcs élevés en régime standard pourraient avoir été davantage motivés que ceux de l'autre groupe à quitter leur parquet pour explorer d'autres environnements. L'élévation des niveaux salivaires de cortisol en cours de transport, soit 6,68 ± 0,80 ng mL -1 pour les porcs du groupe standard contre 3,63 ± 0,58 ng mL -1 pour ceux du groupe enrichi, est difficile à interpréter vu que chez ces derniers l'absence de litière paillée dans les heures précédant le chargement s'était traduite par des niveaux de base plus élevés du cortisol, soit 8,63 ± 1,27 ng mL -1 contre 2,60 ± 0,37 ng mL -1 pour ceux de l'autre groupe. Le régime de logement élargi devrait avoir la préférence étant donné les effets positifs qu'il a sur le bien-être des porcs et qu'il n'entraîne pas de baisse de la qualité de la viande.Mots clés: Comportement, logement, qualité de la viande, physiologie, porc, abattage Increased public interest in meat from welfare-friendly systems has led to an increased number of farms that rear pigs in extensive housing conditions...

Influence of production system in local and conventional pig breeds on stress indicators at slaughter, muscle and meat traits and pork eating quality

“…Thus, the A system did not modify the behaviour and physiological responses of either LW or B pigs to the preslaughtering procedure, which is in accordance with previous results on A v. C system comparisons (Lebret et al, 2006 and. Other studies also showed no effect of enriched environment (increased space allowance, straw bedding) on physiological stress indicators assessed at the end of the lairage period, although the housing conditions influenced animal activity during transport (Geverink et al, 1999;Klont et al, 2001). Conversely, Foury et al (2011) Lebret, Ecolan, Bonhomme, Méteau and Prunier skin lesions and lower plasma CK at slaughter in pigs housed on sawdust bedding with outdoor access compared with conventional housing; however, in their study, pigs were slaughtered in an industrial slaughterhouse, generating more stressful conditions as demonstrated by the much higher average levels of skin lesions and plasma CK levels compared with the present study.…”

Alternative rearing systems in pigs: consequences on stress indicators at slaughter and meat quality

“…Similarly, other studies found that pigs reared outdoors show less aggressive interactions after mixing at loading, during transport and lairage than conventionally reared pigs, even with the same level of mixing (Barton Gade, 2008a;Terlouw et al, 2009). In accordance with previous studies investigating either urinary (Lebret et al, 2006 and2011) or plasma or salivary cortisol (De Jong et al, 1998 andGeverink et al, 1999;Klont et al, 2001;Lebret et al, 2006;Barton Gade, 2008a and2008b), urinary cortisol levels were not affected by the rearing system. Whatever the rearing system, pigs from station 3 exhibited the lowest levels of physical activity and/or stress indicators (plasma CK, cortisol and catecholamines) at slaughter.…”

“…Outdoor or environmentally enriched systems are better perceived than conventional (CON) intensive systems by modern consumers, as CON housing provides a barren environment to animals and prevents them from expressing their natural behaviors (Dransfield et al, 2005;Edwards, 2005). Several studies showed that, in comparison to indoor-reared animals, pigs reared in ALT systems are less aggressive and less active during transport and lairage periods (Geverink et al, 1999;De Jong et al, 2000;Barton Gade, 2008a and2008b;Terlouw et al, 2009). Many studies also show that rearing conditions may affect meat quality.…”

Pre-slaughter conditions, animal stress and welfare: current status and possible future research

“…It is believed that rearing at high density or under barren conditions may disturb the normal development of social behaviour or increase fearfulness, resulting in increased aggression (Schouten, 1986;de Jonge et al, 1996;Olsson et al, 1999;O'Connell et al, 2004). Pigs reared under standard intensive conditions were easier to load, but showed a stronger increase in salivary cortisol during transport and lairage than pigs reared in larger pens or in an enriched environment and their meat had more drip loss (Geverink et al, 1999;De Jong et al, 2000;Klont et al, 2001;Chaloupkova et al, 2007), although opposite results have also been reported (Lambooij et al, 2004).…”