Alternative housing systems for pigs: Influences on growth, composition, and pork quality1

Abstract

Effects of pig birth (first 3-wk period) and rearing environments on growth and muscle quality characteristics of loins were evaluated in three experiments over seasons in west Texas and central Missouri. Housing systems included indoor slatted-floor buildings, indoor deep-bedded buildings, outdoor housing on dirt, and outdoor housing on alfalfa pasture. Experiments were conducted during the growing/finishing phases and pigs were slaughtered at the same age. Loins were collected, vacuum-packaged, and stored for 14 d at 2 degrees C. Pigs born and finished in an outdoor environment during the summer months (Exp. 1) had a greater ADG (0.92 vs 0.82+/-0.06 kg/d, P < 0.05) and had heavier carcass weights (87.9 vs 78.4+/-2.4 kg, P < 0.05) than pigs born and finished in an indoor environment with a slatted-floor finishing building. Carcasses from the outdoor-reared group measured a larger (P < 0.05) loineye area and were fatter (P < 0.01) at the first rib, last rib, and last lumbar vertebra measurements than carcasses from the indoor-reared group. Loin chops from outdoor-reared pigs had darker color scores in the retail display case throughout the 4-d period, measured lower L* values on d 1, and had more discoloration and browning on d 4 than loin chops from the indoor-reared group. During the winter months (Exp. 2), no difference was detected in ADG, carcass measurements, sensory characteristics, or shear force values from indoor-born pigs placed in either an outdoor or indoor finishing environment. Pigs finished on deep bedding (Exp. 3) had heavier carcass weights and more backfat (P < 0.01) than pigs finished on slats, but no differences were detected in sensory panel or shear force results. Overall, carcass measurements, pH, drip loss, sensory panel, and shear force values were similar among the groups finished in different housing systems. Outdoor or deep-bedded systems may increase growth rates of pigs if suitable land area and resources are available, but pork quality of loins will be similar for pigs finished in either conventional or alternative systems.

Effects of deep-bedded finishing system on market pig performance, composition and pork quality

“…In addition, carcasses from Hoop-finished pigs had a higher percentage of calculated FFL (56.9% v. 55.5%) compared with CON-finished pigs. Several other studies have noted lower levels of backfat in pigs finished outdoors or semi-outdoor systems compared with indoor-finished pigs (Warriss et al, 1983;Enfalt et al, 1997;Gentry et al, 2002a). One commonality between these studies is that the pigs were finished in fall or winter months.…”

“…Housing pigs in alternative environments also supports increasing spontaneous exercise and exploratory behaviour (BartonGade and Blaagjerg, 1989;Gentry et al, 2002b;Morrison et al, 2003a), which may lead to changes in stress susceptibility, thereby influencing growth performance and ultimate pork quality (Klont et al, 2001;Morrison et al, 2003b). Few studies have compared growth characteristics from confinement systems to deep-bedded systems (Gentry et al, 2002a;Honeyman and Harmon, 2003). Substantial variation in growth performance and pork quality has been noted in opposing seasons, as well as between confinement and deep-bedded systems (Lebret et al, 2002;Honeyman and Harmon, 2003).…”

Effect of sire breed and rearing system on growth, carcass composition and meat traits of Cinta Senese crossbred pigs

“…Literature is controversial on the influence of alternative housing system on intramuscular fat content, as reviewed by Millet et al (2005). For instance, outdoor rearing, in respect to the indoor one, determined lower IMF content (Enfält et al, 1997;Gentry et al, 2002); or similar values (Van der Wal et al, 1993;Lebret et al, 2002); or higher IMF content (Lebret et al, 2006(Lebret et al, , 2011Trombetta et al, 2009). However, in the present trial, even if the three fat compartments (subcutaneous, intermuscular and Cinta Senese crossbred pigs performance intramuscular) exhibited analogous behaviour in relation to the rearing system, with a tendency to general higher adiposity for indoor housed pigs, it is noteworthy that only at the muscular level the difference became significant, confirming the high sensibility of this depot to environmental manipulation (Lebret et al, 2011) The genetic effect appears more important and affected in similar way both muscles.…”

Genetic and environmental effects on a meat spotting defect in seasoned dry-cured ham

“…Regarding the housing system, with special attention to flooring types, a remarkable list of experimental results have been focused on growing performance, behaviour, carcass traits, fresh meat quality and leg joint disorders (Gentry et al, 2002;Candotti et al, 2004;Lebret et al, 2006). Considering the different mobility allowed to a pig raised on concrete or slatted floor and its impact on a variety of different phenotypes we wondered if a possible reason of our meat spotting defect could be associated to the different use of leg muscles in these two flooring conditions.…”