Effects of diet protein level on different muscle fiber hypertrophy in finishing pigs （Ⅱ） | 饲粮蛋白质水平对肥育猪不同部位肌纤维发育增生的影响（Ⅱ）

Chinese. 研究了饲粮蛋白水平对肥育猪不同部位肌纤维发育增生的影响。采用完全随机区组设计，54头53kg的大×长生长猪随机分为3个处理（每处理3重复），饲喂等氨基酸（TDLys：TDMet：TDThr：TDTrp=100：34．6：71．7：19．2），等消化能（DE3200kcal・kg. 1），不同蛋白水平（CP10％、18％和26％）的3种饲粮，饲喂期67d之后屠宰采样，测背最长肌、腰大肌、半腱肌、半膜肌、臂三头肌、臀中肌的肌纤维间距、肌束间距和肌大束间距。结果表明：饲粮蛋白水平不同，肌纤维各性状指标也不同。肌纤维间距、肌束间距均与饲粮蛋白水平呈正相关（p〈0．01），而肌大束间距与饲粮蛋白水平呈负相关（p〈0．01）。饲粮蛋白水平与肌肉部位均影响肥育猪肌纤维的发育增生，二者间存在交互作用（p〈0．01）。随着肌纤维的增粗，肌大束间距下降。[著者文摘]

English. The experiment comparatively studied the effect of diet protein level on different muscle fiber hypertrophy in finishing pigs. According to a completely randomized block design, 54 growing pigs （Larger×Landrace） with an average weight of 53kg were assigned to three treatments （with three replicates per treatment）. The diets contained a same amino acid pattern （TDLys： TDMet：TDThr：TDTrp=100：34.6：71.7：19.2） and a same digestibile energy level （DE 3200 kcal/kg） with different crude protein levels （CP 10%, 18% and 26% respectively）. The trial lasted for 67 days before slaughter and longissimus dorsi （LD）, psoas major （PM）, semaitendinosus （ST）, semimembranosus （SM）, arm triceps （AT）, glutaeus medius （GM） muscle samples were taken to measure the great muscle bundle distance, muscle fiber distance and muscle bundle distance. There was a positive correlation between muscle fiber distance, muscle bundles distance and protein level （0〈0.01）, a negative correlation between great muscle bundles and protein level （0〈0.01）. The diet protein level and the different muscle all influenced muscle fiber hypertrophy in the finishing pigs, and there was an interaction between them （p〈0.01）. With muscle thickening, there were increases in connective tissue and adipose tissue between muscle, leading to descend of muscle fiber density and distance between great muscle bundles.