Department of Animal Science, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada.
J Anim Sci. 2011 Aug;89(8):2485-90. doi: 10.2527/jas.2010-3204. Epub 2011 Mar 31.
An experiment was conducted to determine the effect of dietary phytic acid (PA) and phytase supplementation on small intestinal histomorphology and Na-dependent glucose transporter 1 (SGLT1) gene expression in piglets. Twenty-four piglets with an average initial BW of 7.60 ± 0.73 kg were randomly assigned to 3 experimental diets, to give 8 piglets per diet. The diets were a casein-cornstarch-based diet that was supplemented with 0 or 2% PA, or 2% PA (as Na phytate) plus an Escherichia coli-derived phytase at 500 phytase units/kg. The basal diet was formulated to meet the 1998 NRC energy, digestible AA, mineral, and vitamin requirements for piglets. After 10 d of feeding, the piglets were killed to determine small intestinal histomorphology and small intestinal SGLT1 gene expression. Phytic acid supplementation did not affect (P > 0.1) villus height (VH) and the VH-to-crypt depth (CD) ratio, but did decrease (P < 0.05) CD in the jejunum. Phytase supplementation did not affect (P > 0.1) VH, CD, and the VH-to-CD ratio. Phytic acid supplementation reduced SGLT1 gene expression in the duodenum, jejunum, and ileum by 1.1-, 5.4-, and 2.4-fold, respectively. Phytase supplementation increased SGLT1 gene expression in the jejunum by 2.6-fold, but reduced SGLT1 gene expression in the duodenum and ileum by 2.0- and 4.0-fold, respectively. In conclusion, PA reduced CD in the jejunum and SGLT1 gene expression in the duodenum, jejunum, and ileum, whereas phytase supplementation increased the expression of SGLT1 in the jejunum. The reduced SGLT1 gene expression by PA implies that PA reduces nutrient utilization in pigs partly through reduced expression of SGLT1, which is involved in glucose and Na absorption. The increased expression of SGLT1 in the jejunum by phytase supplementation implies that phytase alleviated the negative effects of PA partly through increased expression of SGLT1.
进行了一项实验，以确定日粮植酸（PA）和植酸酶添加对仔猪小肠形态学和钠依赖性葡萄糖转运体 1（SGLT1）基因表达的影响。24 头平均初始体重为 7.60±0.73kg 的仔猪被随机分配到 3 种实验日粮中，每种日粮 8 头仔猪。日粮以酪蛋白-玉米淀粉为基础，补充 0 或 2%的 PA，或 2%的 PA（以植酸钠形式）加 500 植酸酶单位/kg 的大肠杆菌来源的植酸酶。基础日粮的配制符合 1998 年 NRC 能量、可消化氨基酸、矿物质和维生素对仔猪的需求。饲养 10d 后，处死仔猪以确定小肠形态学和小肠 SGLT1 基因表达。植酸添加并未影响（P＞0.1）绒毛高度（VH）和 VH-隐窝深度（CD）的比值，但降低了空肠的 CD（P＜0.05）。植酸酶添加并未影响（P＞0.1）VH、CD 和 VH-CD 比值。植酸添加使十二指肠、空肠和回肠的 SGLT1 基因表达分别降低了 1.1、5.4 和 2.4 倍。植酸酶添加使空肠的 SGLT1 基因表达增加了 2.6 倍，但使十二指肠和回肠的 SGLT1 基因表达分别降低了 2.0 倍和 4.0 倍。总之，PA 降低了空肠的 CD 和十二指肠、空肠和回肠的 SGLT1 基因表达，而植酸酶添加增加了空肠的 SGLT1 表达。PA 降低 SGLT1 基因表达表明，PA 通过降低参与葡萄糖和 Na 吸收的 SGLT1 表达，部分降低了猪对养分的利用。植酸酶添加增加空肠 SGLT1 表达表明，植酸酶部分通过增加 SGLT1 表达缓解了 PA 的负面影响。
