Abstract
Simple SummaryPeople’s demand for meat consumption has transformed from quantity to quality. The rearing condition is one of the factors affecting meat quality. However, the effects of different rearing conditions on the production of Chinese indigenous pig breeds are still barely understood. In this study, Heigai pigs (a Chinese indigenous pig breed) were raised in the indoor feeding farm and the grazing farm to investigate the effects of different rearing conditions on carcass traits, meat quality and the compositions of fatty acid and amino acid. Grazing farm pigs tended to increase shear force, while significantly increasing the saturated fatty acid ratio and decreasing the unsaturated fatty acid ratio to alter the composition of fatty acids of longissimus thoracis et lumborum. The present study provides an experimental reference for regulating the production of superior meat quality pork of Chinese local breed pigs.The present study evaluates the influence of captivity and grazing rearing conditions on the carcass traits, meat quality and fatty acid profiles of Heigai pigs. Ten Heigai pigs with market weight were randomly selected from both the indoor feeding farm and outdoor grazing farm groups (FF and GF; five pigs per group) for measuring production performance. The results showed that the shear force of longissimus thoracis et lumborum (LTL) in the GF group tended to increase (p = 0.06), and triglyceride and cholesterol contents in LTL and psoas major muscle (PMM) of the GF group significantly increased and decreased, respectively (p < 0.05). The proportion of saturated fatty acids (SFA) was significantly increased (p < 0.05) in the GF group. Meanwhile, the ratios of unsaturated fatty acid (UFA), polyunsaturated fatty acid (PUFA), monounsaturated fatty acid (MUFA) and the content of flavor amino acid of the LTL in the GF group were significantly decreased (p < 0.05). The GF upregulated the expression of MyHC-IIb and lipogenic genes, such as GLUT4 and LPL (p < 0.05), in LTL and PMM, but downregulated the expression of MyHC-I, MyHC-IIa, PPARγ and leptin (p < 0.05). In conclusion, these results suggested that the different rearing conditions can alter the meat qualities by mediating the muscle fiber type and lipid metabolism of Heigai pigs.
Highlights
Meat quality assessment is a comprehensive concept, including meat appearance, color, tenderness, juiciness and flavor, which largely depends on the breed, nutrition, rearing system and post-slaughter handling [1]
The results showed that the rearing conditions had no significant effect on the carcass traits, including slaughter weight, carcass weight, lean percentage, backfat thickness and loin muscle area
The shear force of longissimus thoracis et lumborum (LTL) in the grazing farm (GF) group was higher than the feeding farm (FF) group (p = 0.06), suggesting that rearing conditions can mainly affect the shear force of LTL in Heigai pigs
Summary
Meat quality assessment is a comprehensive concept, including meat appearance, color, tenderness, juiciness and flavor, which largely depends on the breed, nutrition, rearing system and post-slaughter handling [1]. In addition to the above external factors, muscle fiber types, proportion and lipid composition of intramuscular fat (IMF) play an important role in the determination of meat quality [2]. The composition of muscle fibers is related to IMF deposition [5], as type I and IIa fibers have large amounts of lipid accumulation, whereas IIx and IIb fibers allow less storage of lipids [6]. The number and composition of different types of muscle fibers directly affect various aspects of meat quality and are critical to its nutritional value. The effect of housing (indoor) and grazing (outdoor/free-range) rearing conditions on meat quality has been widely explored and discussed
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
