Diverse birth and rearing environment effects on pig growth and meat quality1

Abstract

Birth and rearing conditions were evaluated for their effects on pig growth, body composition, and pork quality using 48 barrows during the spring and summer months. Pigs were either farrowed in indoor crates or outdoor huts. At weaning, indoor-born and outdoor-born pigs were randomly allotted to indoor or outdoor treatments for growing/finishing. Body weight data were collected. Pigs were transported 5 h to a commercial processing plant, allowed 2 h of rest, and then processed as a group under commercial conditions. Boneless loins were collected from the left side of each carcass and aged for 14 d. Objective and subjective color measurements were taken on the longissimus muscle at the 10th rib on d 14 postmortem. Loin chops were evaluated for sensory attributes, shear force, and retail display features. Pigs born outdoors were heavier and had greater ADG at all growth intervals after weaning (d 28, 56, 112, and final weight, P < 0. 05) than pigs born indoors. Outdoor-born pigs had heavier carcass weights (91.2 vs 81.3+/-3.4 kg, P < 0.001), larger loineye areas (54.6 vs 49.7+/-0.2 cm , P < 0.05), and higher pork flavor intensity scores (6.5 vs 6.1+/-0.10, P < 0.01) than indoor-born pigs. Birth x rearing environment interactions were not significant for most measures. Backfat measurements at the last rib were greater (3.2 vs 2.8+/-0.05 cm, P < 0.05) for the pigs reared outdoors than for the pigs reared indoors. Pigs finished outdoors had more reddish pink color scores, lower shear force values, and lower L* values, indicating darker-colored pork, compared with pigs finished indoors (P < 0.05). Pig birth environment played a significant role in improving growth rates of outdoor-born pigs and increasing pork flavor intensity scores of loin chops from pigs born outdoors. Finishing pigs outdoors may improve pork color and tenderness but also may increase backfat thickness when they are fed conventional diets.

Influence of rearing system, diet and gender on performance, carcass traits and meat quality of Polish Landrace pigs

“…The influence of outdoor rearing on pig performances varies according to many factors, such as housing, genetics, climatic conditions, space allowance and feeding regimen (Lebret et al, 2006). Gentry et al (2002) did not find any effect on pig growth and carcass weight of rearing environment (indoors on slats or outdoors fed alfalfa pasture). Lebret et al (2006) reported that pigs reared in an outdoor system (sawdust bedding with free access to an outdoor area, 2.4 m 2 /pig) exhibited better growth rate due to their greater feed intake, especially during the finishing period, and heavier carcasses compared with pigs reared in the conventional system (fully slatted floor, 0.65 m 2 /pig).…”

“…Some studies have determined that pigs finished outdoors had less backfat than pigs finished indoors (Enfä lt et al, 1997;Sather et al, 1997). Other studies (Gentry et al, 2002;Lebret et al, 2006) have reported to the contrary. In addition, Lebret et al (2006) found lower lean meat content in pigs reared outdoors, but other authors (Hö gberg et al, 2004) did not report any effect between indoor and outdoor systems on intramuscular fat -E-mail: maior@unimol.it content and lean percentage.…”

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

“…In addition, using deep-bedded structures is an environmental enrichment strategy that has been shown to stimulate foraging and/or explorative behaviour (De Jong et al, 1998;O'Connell et al, 2004). 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). Seasonal alterations in fatty acid profiles (Cava et al, 2000;Bee et al, 2004), flavour attributes of fresh pork, including intensity and pork flavour (Gentry et al, 2002b), and overall flavour acceptability (Enfalt et al, 1997) have also been noted between pigs finished in deep-bedded and outdoor systems compared with indoor systems.…”

The feeding and rearing systems of Iberian pigs affect the lipid composition and texture profile of dry-cured loin

“…Some studies in pigs of improved genotypes fed on grass showed no effects on meat quality (Danielsen et al, 2000). On the other hand, the effect of the outdoor rearing has also been studied in light breed pigs but in most of the cases this has resulted in lack of improvements in pig performance (Gentry et al, 2002). Other authors reported increased meat tenderness due to the higher activity of the pigs (Dufey, 1995).…”