日粮不同蛋白水平对猪小肠CaSR基因表达及胃肠激素分泌的影响  

Effects of dietary protein contents on CaSR expressions in small intestine and serum gastrointestinal hormone levels

作　　者：赵秀英[1] 孟祥龙[1] 伍力[2] 李铁军[2] 丁立人[1] 朱伟云[1] 杭苏琴[1] 

机构地区：[1]南京农业大学消化道微生物研究室,江苏南京210095 [2]中国科学院亚热带农业生态研究所,湖南长沙410125

出　　处：《畜牧与兽医》2016年第12期30-35,共6页Animal Husbandry & Veterinary Medicine

基　　金：国家973项目(2013CB127301)

摘　　要：本试验旨在研究日粮蛋白水平对不同生理阶段猪胃肠道钙敏感受体(Calcium-sensing receptor,Ca SR)基因表达、血液胃肠激素分泌的影响,探讨蛋白水平与Ca SR基因表达和胃肠激素分泌的关系。选择健康、体重相近约10 kg(9.57±0.64)kg杜×长×大三元杂交断奶仔猪、35kg(36.47±0.20)kg生长猪和60 kg(62.30±0.07)kg肥育猪各18头,分阶段饲养,每阶段18头猪随机分为3组,每组6头,单栏饲养,以玉米-豆粕型日粮为基础,断奶仔猪日粮粗蛋白水平为20%、17%、14%,生长猪日粮粗蛋白水平为18%、15%、12%,肥育猪日粮粗蛋白水平为16%、13%、10%,饲养期分别为45、30、50 d,试验结束后屠宰,采集前腔静脉血液、小肠各部位组织,测定血液中胃肠激素水平、小肠各部位组织中Ca SR的表达。结果表明:当日粮蛋白水平降低后,不同阶段猪小肠Ca SR基因表达下调(P<0.05),断奶仔猪血清胆囊收缩素(CCK)、胰高血糖素样肽-1(GLP-1)和酪酪肽(PYY)浓度显著降低,生长猪血清CCK、葡萄糖促胰岛素肽(GIP)浓度也明显下降,而肥育猪只有血清GIP浓度显著降低(P<0.05);相关性分析表明,断奶仔猪空、回肠Ca SR表达与血中GLP-1和GIP显著正相关(P<0.05),回肠Ca SR表达与血中PYY存在显著正相关(P<0.05);生长猪十二指肠Ca SR表达与CCK显著正相关(P<0.05),而空、回肠Ca SR表达则与GIP显著正相关(P<0.05);肥育猪小肠各段Ca SR表达与胃肠激素无明显相关。我们的结果说明,降低猪日粮蛋白水平可下调小肠Ca SR基因表达和血液中CCK等胃肠激素的分泌,日粮蛋白水平对胃肠激素分泌的影响可能通过Ca SR介导。The objective of this experiment was to investigate the effect of dietary protein contents on expressions of Ca SR（ Calcium-sensing receptor） in small intestine and serum gastrointestinal hormone levels in different physiological stage of pigs and explore the relationship between Ca SR expression and gastrointestinal hormone secretion. Total 54 cross-bred（ Duroc × Landrace × Yorkshire） pigs with good health and similar body weight were selected,including 18 weaned pigs at 10 kg（ 9. 57 ± 0. 64） kg,18 growing pigs at 35 kg（ 36. 47 ± 0. 20） kg and 18 finishing pigs at 60 kg（ 62. 30 ± 0. 07） kg,respectively. Eighteen pigs in different stage were randomly divided into 3 groups and fed with corn-soybean meal basal diet. The dietary crude protein（ CP） levels for weaned pigs were 20%（ NRC standard）,17% and 14%,and for growing pigs were 18%（ NRC standard）,15% and 12%,and for finishing pigs were 16%（ NRC standard）,13% and 10%. After experimental period of 45 days for weaned pigs,30 days for growing pigs and 50 days for finishing pigs,respectively,all pigs were slaughtered. The Precaval vein blood and the small intestine tissue were collected for the analysis of gastrointestinal hormones and Ca SR expressions. With the reduction of dietary protein,serum concentrations of CCK,GLP-1 and PYY showed a significant decrease in piglets,and the same alteration as the CCK,GIP concentrations in growing pigs and GIP concentration in finishing pigs（ P 〈0. 05）. Low protein diets significantly de-creased the expression of CaSR in small intestine among piglets,growing and finishing pigs（ P 〈0. 05）. The correlation analysis suggested that a significant positive correlation were revealed in the expression of jejunal and ileal CaS R and the concentration of GLP-1 and GIP,the same variation between the expression of ileal CaSR and the concentration of PYY in piglets. In growing pigs,there was a significant positive correlation between the expression of CaSR in duodenum and the concentration

关 键 词：蛋白水平 断奶仔猪 生长猪 肥育猪 Ca SR 胃肠激素 

分 类 号：S811.3[农业科学—畜牧学]