Impact of spontaneous exercise on performance, meat quality, and muscle fiber characteristics of growing/finishing pigs1

Abstract

The objective of this experiment was to determine if increased space and exercise for finisher pigs (0.90 vs 9.45 m2/pig) affects performance, meat quality, or muscle fiber characteristics. Newsham barrows (n = 32, 4 pens/treatment) were placed in one of two space allocations: control space allowance (CONT) or in a long pen with increased space allowance (10x). Pigs were weighed every 28 d and feed intake/pen was calculated. Pigs were filmed for behavioral analysis on d 70 and 100 using video recorders to determine walking distances over a 24-h period. After a 5-h transport and 2-h rest period, pigs (approximately 115 kg) were slaughtered on the same day at a commercial facility. Muscle samples were obtained from the longissimus lumborum (LL) and semimembranosus (SM) muscles within 1 h postmortem for muscle fiber typing. Backfat thickness and pH decline were measured on the left side of each carcass. After 24-h chilling, a boneless loin was collected from each pig and stored at 2 degrees C until analyzed. On d 14 postmortem, loins were cut at the 10th rib for color evaluations, and chops were cut for Warner-Bratzler shear (WBS) force and sensory analysis. Histochemical staining methods were used for the detection of type I, IIA, and IIB/X muscle fiber types. There were no significant differences (P > 0.10) in live weight, ADG, ADFI, or G:F ratio of the two experimental groups evaluated. Pigs finished in 10x pens walked a greater (P < 0.01) distance over a 24-h period than pigs finished in the CONT pens. Pigs finished in the lOx pens were fatter (P < 0.05) at the last lumbar vertebra than pigs finished in the CONT pens, but no significant differences were found in loineye area, loin color, marbling scores, WBS, sensory panel scores, retail display measures, or muscle fiber type percentages. Expanded space allowance to increase exercise resulted in no improvements in pig performance, pork loin measures, or muscle characteristics.

Effects of space allocation within a deep-bedded finishing system on pig growth performance, fatty acid composition and pork quality

“…Current research exploring strategies in alternative production systems has revealed that increasing space allocation stimulates foraging or explorative behaviour in pigs, thereby increasing favourable interactions and lowers stress susceptibility among pigs (Guy et al, 2002;Olsen et al, 2002;Van de Weerd et al, 2003). Increasing space allocation also influences growth and carcass composition characteristics, stimulating improved growth performance and carcass composition (Gentry et al, 2002b;Honeyman and Harmon, 2003). Reduction in stress may promote an increase in growth and performance of pigs.…”

“…Furthermore, allocating more space during finishing has been shown to affect behaviour and peri mortem metabolism (Beattie et al, 2000;Klont et al, 2001), which may lead to differences in ultimate pork quality. Although several studies have reported increased acceptability of pork from pigs finished in systems that allocate more space (Gentry et al, 2002a and2002b;Estevez et al, 2003), these experiments are mainly comparisons of increased stocking density as well as comparisons of indoor and alternative or outdoor production systems. Research linking pork quality with varying stocking rates within certain alternative production systems is limited.…”

Short communication. Effect of housing system during the finishing period on growth performance and quality fat of Iberian pigs

“…The exercise influence on performances is controversial due to the different exercise level and climatic conditions. Thus, some experiments (Gentry et al, 2002;López-Bote et al, 2008) did not f ind moderate exercise effect on productive results and carcass traits, but other studies (Bee et al, 2004;Daza et al, 2006;Lebret et al, 2006) observed ADG reduction and AFDI and FCR increase in outdoor pigs due to that the differences of exercise or climatic conditions between outdoors and indoors pigs were more important.…”

“…meat quality because of physical activity (Gentry et al, 2002), however other reports have observed that exercise affects to meat quality (Gevering et al, 1998). It is known that the acceptability and quality of the products from Iberian pig are mainly attributed to differences in the fatty acid composition of adipose tissue.…”

Compositional Studies on Mangalitsa Meat Products for Public Consumption

“…There is not much information on the effects of grass intake and the meat characteristics, some even suggest that there isn't any (Danielsen et al, 2000). The effects of traditional breeding, which imply outdoor rearing, has also been studied in other breeds but no major differences in the quality of meat were observed (Gentry et al, 2002;Bee Guex and Herzog, 2004 …”