不同来源纤维在生长猪消化道内的食糜理化特性和养分消化率

Effect of fiber sources on physico-chemical properties of digesta and digestibilities of nutrients in duodeum and ileum double fistulated growing pigs

[目的]旨在研究4种纤维原料对生长猪十二指肠和回肠食糜,粪便p H值、黏度和持水力的影响,以及4种纤维日粮养分在消化道不同区段的消化状况。[方法]选用西兰花、小麦麸、大豆皮和米糠4种原料配制单一纤维来源的日粮。试验选用体质量35 kg左右的(杜洛克×大白猪×长白猪)三元杂交阉公猪8头,分别安装十二指肠和回肠末端双瘘管,按4×4拉丁方设计安排试验。[结果]小麦麸日粮组猪的回肠末端食糜p H值显著低于其余3种日粮组(P<0.05),大豆皮和米糠日粮组猪的粪便p H值显著低于西兰花和小麦麸日粮组(P<0.05);4种日粮组猪的十二指肠食糜黏度差异不显著(P>0.05),但大豆皮日粮组猪的回肠末端食糜黏度显著高于米糠日粮组(P<0.05)。小麦麸日粮组猪十二指肠前段的干物质、粗蛋白和淀粉表观消化率显著高于西兰花日粮组(P<0.05),而中性洗涤纤维的表观消化率显著低于西兰花日粮组(P<0.05)。大豆皮日粮组猪的回肠末端灰分和淀粉表观消化率均显著高于其他3种日粮组(P<0.05)。小麦麸日粮组猪的全消化道灰分、干物质、粗蛋白、粗脂肪和淀粉表观消化率均显著高于米糠日粮组(P<0.05)。西兰花日粮组猪的全消化道灰分、粗蛋白和粗脂肪表观消化率显著低于其他3种日粮组(P<0.05),而有机物、中性洗涤纤维和酸性洗涤纤维的全消化道表观消化率显著高于其他3种日粮组(P<0.05)。[结论]本试验配制的4种纤维含量相近、来源不同的半纯合日粮其养分的消化部位(胃、小肠和大肠),以及各位点的表观消化率表现出明显差异,日粮纤维来源对猪消化道食糜的吸水力和黏度也有一定影响。

[ Objectives]The study was conducted to investigate the effects of dietary fiber sources on physico-chemical properties of digesta and nutrient digestibilities in the different segments of the digestive tract of growing pigs. [ Methods ] Eight healthy Duroc x Landrace Yorkshire crossbreed male castrated growing pigs with an average body weight of 35 kg were subjected to fistula surgery at both the proximal duodenum and terminal ileum. Four semi-purified diets of similar neutral detergent fiber content, with each diet formulated with sole fiber source（ i. e, wheat bran, rice bran, soybean hull, and broccoli meal, respectively）, were randomly allotted to 2 pigs based on replicated 4~4 Latin square design. [ Results]The pH value of ileal digesta of wheat bran diet was significantly lower than those of any other three diets（P〈0.05）. The pH values of feces of soybean hull diet and rice bran diet were significantly lower than that of the other two diets （P〈0.05）. No difference was found with respect to the viscosity of duodenal digesta across the four diets. The viscosity of ileal digesta of soybean hull diet was significantly higher than that of rice bran diet（P〈0.05）. Pigs fed with wheat bran diet showed significantly higher digestibility of dry matter（ DM）, crude protein （CP）and starch in duodenum than they were provided with broccoli meal diet. Compared to the other diets, soybean hull diet showed higher crude ash and starch digestibilities at the terminal of ileum. The ash, DM, CP, ether extract （EE）and starch of wheat bran diet were more digestible in the whole digestive tract than those of rice bran diet. On the contrary, pigs showed highest apparent total tract digestibility of ash, CP and EE, and lowest of organic matter （OM） ,neutral detergent fiber （NDF）, acid detergent fiber （ADF）when fed broccoli meal diet. [ Conclusions ] The physio-chemical properties of digesta and nutrient digestibility of diets at different section of pig were profoundly affected by source of dietary fiber. It may relate to the chemical composition and structure of their cell walls.