Abstract:
This experiment evaluated the difference between computer-controlled simulated digestion and in vivo stomach-small intestinal or large intestinal digestion for growing pigs. Five diets including a corn-soybean meal basal diet and four experimental diets with rapeseed meal (RSM), cottonseed meal (CSM), sunflower meal (SFM), or peanut meal (PNM) were assigned to each group of five barrows installed terminal ileal cannula or distal cecal cannula in a 5 × 5 Latin square design. Ileal digesta and feces were collected for the determination of digestibility of dry matter (DM) and gross energy (GE) as well as digestible energy (DE) at terminal ileum and total tract. The large intestinal digestibility and DE were calculated by the difference between measurements obtained at the terminal ileum and those obtained from total tract. In vitro stomach-small intestinal digestibility and DE for diets and plant protein meals were determined by stomach-small intestinal digestion in a computer-controlled simulated digestion system (CCSDS). The in vitro large intestinal digestibility and DE of diets were determined in a CCSDS using ileal digesta and enzymes extracted from cecal digesta of pigs. The in vitro large intestinal digestibility and DE of four plant protein meals were determined by the difference between stomach-small intestinal and total tract digestion in the CCSDS. For the experimental diets, the in vitro ileal digestibility and DE were not different from corresponding in vivo values in basal diet and PNM diet, but greater than corresponding in vivo values for diets with RSM, CSM, and SFM (P < 0.05). No difference was observed between in vitro and in vivo large intestinal digestibility and DE in five diets. For the feed ingredients, the in vitro ileal digestibility and DE did not differ from corresponding in vivo ileal values in RSM and PNM but were greater than the in vivo ileal values in CSM and SFM (P < 0.05). The in vitro large intestinal GE digestibility and DE were not different from in vivo large intestinal values in RSM, CSM, and PNM, but lower than in vivo large intestinal values in SFM. This finding may relate to the higher fiber content of plant protein meals resulting in shorter digestion time of in vivo stomach-small intestine thus lower digestibility compared to in vitro, indicating it is necessary to optimize in vitro stomach-small intestinal digestion time.
Comparable in vitro and in vivo values are crucial to develop a novel in vitro digestion technique for growing pigs. The current study evaluated the difference between computer-controlled simulated digestion and in vivo stomach–small intestinal or large intestinal digestion for growing pigs. Five diets including a corn–soybean meal basal diet and four experimental diets with rapeseed meal (RSM), cottonseed meal (CSM), sunflower meal (SFM), or peanut meal (PNM) were used to compare the in vitro and in vivo digestion. Our study demonstrated that the in vitro ileal digestibility of energy was not different from corresponding in vivo values in basal diet and PNM diet, but greater than corresponding in vivo values for diets with RSM, CSM, and SFM. The in vitro stomach–small intestinal digestibility was greater than in vivo digestibility, resulting in less digestible substrates hydrolyzed by in vitro large intestinal fluid, whereas more digestible substrates can be digested by in vivo large intestine in plant protein meals. This difference may relate to the higher fiber content of plant protein meals resulting in shorter digestion time of in vivo stomach–small intestine thus lower digestibility compared to in vitro. Therefore, it is necessary to optimize in vitro stomach–small intestinal digestion time.
摘要:
该实验评估了计算机控制的模拟消化与生长猪体内胃-小肠或大肠消化之间的差异。五种饮食,包括玉米豆粕基础饮食和四种带有菜籽粕(RSM)的实验饮食,棉籽粕(CSM),向日葵粉(SFM),或花生粉(PNM)以5×5拉丁正方形设计分配给每组五个安装回肠末端套管或盲肠远端套管的手推车。收集回肠消化物和粪便,以确定回肠末端和整个管道的干物质(DM)和总能量(GE)以及可消化能量(DE)的消化率。通过在回肠末端获得的测量值与从整个肠道获得的测量值之间的差异来计算大肠消化率和DE。在计算机控制的模拟消化系统(CCSDS)中,通过胃-小肠消化来确定饮食和植物蛋白膳食的体外胃-小肠消化率和DE。使用回肠消化物和从猪的盲肠消化物中提取的酶,在CCSDS中确定了饮食的体外大肠消化率和DE。通过CCSDS中胃-小肠和总道消化之间的差异,确定了四种植物蛋白粉的体外大肠消化率和DE。对于实验性饮食,体外回肠消化率和DE与基础饮食和PNM饮食中相应的体内值没有差异,但大于RSM饮食的相应体内值,CSM和SFM(P<0.05)。在五种饮食中,体外和体内大肠消化率和DE之间没有观察到差异。对于饲料成分,RSM和PNM的体外回肠消化率和DE与相应的体内回肠值没有差异,但大于CSM和SFM的体内回肠值(P<0.05)。在RSM中,体外大肠GE消化率和DE与体内大肠值没有差异,CSM,和PNM,但低于体内大肠值的SFM。这一发现可能与植物蛋白膳食的纤维含量较高有关,导致体内胃-小肠的消化时间较短,因此与体外相比消化率较低。表明有必要优化体外胃-小肠消化时间。