乳酸对仔猪消化酶发育的影响

为了研究乳酸对断奶仔猪消化酶发育的影响，采用144头刚断奶的杜大长商品仔猪，随机分为对照组（基础饲粮）、基础+3 g·kg-1乳酸酸化剂组和基础+6g·kg-1乳酸酸化剂组，试验为期28 d。分别在试验第7，14和28天，每组屠宰9头试验猪，分别取胃和十二指肠内容物、取十二指肠和空肠用于组织切片，用无菌玻片刮取小肠黏膜用于测定黏膜酶活。测定了添加乳酸对饲料pH和缓冲值、仔猪胃和十二指肠内pH、胃内容物胃蛋白酶活性、小肠内容物胰蛋白酶活性和二糖酶活性、小肠绒毛高度和黏膜二糖酶活性。结果表明：添加乳酸降低了饲料和胃内 pH，显著提高仔猪胃内容物胃蛋白酶活性；提高小肠内容物胰蛋白酶和二糖酶活性；提高十二指肠和空肠绒毛高度，提高了小肠黏膜二糖酶的活性。结果表明，添加乳酸能促进仔猪消化酶的发育，并通过胃和小肠多个环节的作用，提高仔猪对饲料营养物质的消化能力，从而促进仔猪的生长。

Effects of lactic acid on development of digestive enzyme in piglets

Abstract: Experiment was conducted to evaluate the effects of lactic acid on development of digestive enzyme in piglets. 144 Duroc×Landrace×Yorkshire piglets were divided into 3 groups randomly， the control（basal diet），basal+3 g·kg-1 lactic acidifier and basal+6 g·kg-1 lactic acidifier， and the experiment lasted for 28 days. On the 7th， 14th and 28th day of experiment， 9 pigs were slaughtered， gastric and duodenal contents were taken out， duodenum and jejunum were taken for tissue slice， the intestinal mucosa was scraped for determination of enzyme activities. The pH and buffer value of feed were determined before animal trial. The pH of gastric and duodenum content， pepsin activity of gastric content， tripsin activity of duodenum content， disaccharidase activity of small intestinal， height of intestinal villus， and mucosa disaccharidase activity were determined on the 7th，14th and 28th day of trial. Results showed that supplement of lactic acid decreased pH of feed and gastric content， increased the pepsin activity of gastric content; increased the tripsin activity of duodenum content and disaccharidase activity of small intestinal; increased height of duodenum and jejunum villus; increased mucosa activity of disaccharidase. The results indicated addition of lactic acid improved the development of digestive enzyme， and promoted growth performance of pig via improvement of gastric and small intestinal development.