【摘要】：生產(chǎn)中給奶畜飼喂高精料日糧來(lái)滿足反芻動(dòng)物泌乳期能量需求的飼喂模式已成為一種流行趨勢(shì)。但是,奶畜攝入高精料日糧可導(dǎo)致瘤胃中揮發(fā)性脂肪酸的沉積和瘤胃液中異常代謝產(chǎn)物脂多糖的釋放增加,進(jìn)而轉(zhuǎn)移入血液,經(jīng)門靜脈入肝臟,從而影響肝臟基因表達(dá)和營(yíng)養(yǎng)重分配,然而其具體影響的途徑和機(jī)制尚不清楚。本研究以關(guān)中奶山羊?yàn)閯?dòng)物模型,模擬實(shí)際生產(chǎn)中的喂養(yǎng)模式,通過(guò)在日糧中添加高比例的精料來(lái)揭示長(zhǎng)期飼喂高精料日糧對(duì)關(guān)中奶山羊血液生化指標(biāo)和肝臟糖脂代謝的影響,為科學(xué)飼養(yǎng)泌乳期的奶山羊提供理論基礎(chǔ)。本課題的研究?jī)?nèi)容和結(jié)果如下:本試驗(yàn)選用14頭體重相近、健康狀況良好,泌乳初期的經(jīng)產(chǎn)2~3胎的關(guān)中奶山羊,隨機(jī)分為2組,對(duì)照組為6只,試驗(yàn)組為8只,其中對(duì)照組的奶山羊被飼喂精粗比為35:65的日糧,試驗(yàn)組的奶山羊被飼喂精粗比為65:35(高精料組)的日糧,試驗(yàn)期為19周,在試驗(yàn)期間可自由飲水,每日活動(dòng)兩次。1.采取頸靜脈血測(cè)定血液生化參數(shù),結(jié)果表明,飼喂高精料日糧的試驗(yàn)組奶山羊血漿中谷丙轉(zhuǎn)氨酶濃度顯著升高(P0.05),甘油三酯有下降的趨勢(shì)(P=0.099),但是,在長(zhǎng)期飼喂高精料日糧的條件下,血液中大部分的生化指標(biāo)并沒(méi)有發(fā)生顯著性的變化(P0.05)。2.運(yùn)用經(jīng)典的HE染色,染色結(jié)果顯示高精料日糧可以引起奶山羊肝細(xì)胞高度腫脹,體積變大,胞漿溶解,肝細(xì)胞呈腫脹變性或空泡樣變性。3.通過(guò)Real-time PCR檢測(cè)肝臟脂代謝相關(guān)基因表達(dá),結(jié)果顯示,長(zhǎng)期飼喂高精料日糧的試驗(yàn)組奶山羊肝臟脂代謝關(guān)鍵基因的表達(dá)均未發(fā)生顯著性變化(P0.05)。雖然,在長(zhǎng)期飼喂高精料日糧的條件下,實(shí)驗(yàn)組肝臟脂代謝相關(guān)基因LPL、SCD、FADS2 mRNA的表達(dá)量有所升高,但是卻沒(méi)有達(dá)到顯著的水平。4.Real-time PCR檢測(cè)肝臟糖異生關(guān)鍵酶的表達(dá),結(jié)果顯示,肝臟糖異生關(guān)鍵基因PEPCK-c和Fbp1的mRNA的表達(dá)均顯著下降(P0.05),說(shuō)明高精料日糧抑制了肝臟的糖異生作用。5.免疫印跡結(jié)果表明Fbp1的蛋白表達(dá)顯著下降(P0.05);但是,酶活性測(cè)定結(jié)果顯示Fbp1的活性顯著升高(P0.05)。6.通過(guò)Real-time PCR檢測(cè)肝臟轉(zhuǎn)錄相關(guān)調(diào)控因子的表達(dá),結(jié)果顯示,試驗(yàn)組奶山羊肝臟肝X受體和視黃醇γ受體mRNA的表達(dá)顯著降低(P0.05)。本研究結(jié)果顯示,長(zhǎng)期飼喂高精料日糧可導(dǎo)致血液中谷丙轉(zhuǎn)氨酶升高,提示這可能與肝細(xì)胞受損有關(guān),但是脂類代謝的相關(guān)基因表達(dá)均沒(méi)有發(fā)生顯著變化。肝細(xì)胞損傷可能抑制了肝臟轉(zhuǎn)錄相關(guān)基因的表達(dá),進(jìn)而抑制了肝臟糖異生作用。
[Abstract]:It has become a popular trend to feed dairy animals with high concentrate diets to meet the energy requirements of ruminants during lactation. However, intake of high concentrate diet led to the accumulation of volatile fatty acids in rumen and the release of abnormal metabolite lipopolysaccharide from rumen fluid, and then transferred into blood and liver through portal vein. Thus affecting liver gene expression and nutrient redistribution, however, the specific impact of the pathway and mechanism is not clear. In this study, Guanzhong dairy goat was used as an animal model to simulate the feeding mode in actual production. The effect of long-term feeding high concentrate diet on blood biochemical index and hepatic glucose and lipid metabolism of Guanzhong dairy goat was revealed by adding a high proportion of concentrate to the diet. To provide a theoretical basis for the scientific feeding of dairy goats during lactation. The research contents and results are as follows: 14 Guanzhong dairy goats with similar body weight and good health were randomly divided into two groups: control group (n = 6) and experimental group (n = 8). The milk goats of the control group were fed the diet of 35:65, and the dairy goats of the test group were fed the diet of 65:35 (high concentrate group) for 19 weeks. During the trial period, they were free to drink water and exercise twice a day. The blood biochemical parameters were measured by jugular vein blood. The results showed that the plasma concentration of alanine aminotransferase in dairy goats fed high concentrate diet was significantly increased (P0.05), and triglyceride decreased (P0. 099). Under the condition of feeding high concentrate diet for a long time, most of the biochemical indexes in blood did not change significantly (P0.05). 2. The results of classical HE staining showed that high concentrate diet could cause high swelling of hepatocytes, large volume, cytoplasmic dissolution, swelling or vacuolar degeneration of liver cells. The expression of liver lipid metabolism related genes was detected by Real-time PCR. The results showed that there was no significant change in the expression of key genes of liver lipid metabolism in dairy goats fed with high concentrate diet for a long time (P0.05). Although the expression of liver lipid metabolism-related gene LPL,SCD,FADS2 mRNA was increased in the experimental group under the condition of high concentrate diet for a long time, it did not reach a significant level. 4. Real-time PCR was used to detect the expression of hepatic glycosylated key enzymes. The expression of mRNA in PEPCK-c and Fbp1 decreased significantly (P0.05), which indicated that high concentrate diet inhibited hepatic glycosylation. 5. Western blotting showed that the protein expression of Fbp1 decreased significantly (P0.05), but the activity of Fbp1 increased significantly (P0.05). The expression of transcription-related regulatory factors in liver was detected by Real-time PCR. The results showed that the expression of X receptor and retinol 緯 receptor mRNA in liver of dairy goats in the experimental group was significantly lower than that in the control group (P0.05). The results showed that long-term feeding of high concentrate diet led to the increase of blood alanine aminotransferase, suggesting that this may be related to the damage of hepatocytes, but the expression of genes related to lipid metabolism did not change significantly. Hepatocyte injury may inhibit the expression of transcriptional genes in the liver and thus inhibit the hepatic glycosylation.
【學(xué)位授予單位】：西北農(nóng)林科技大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：S827.5

【參考文獻(xiàn)】

相關(guān)期刊論文 前3條

1 薛妮娜;王曉娟;王莉莉;;肝臟G蛋白偶聯(lián)受體與糖代謝調(diào)節(jié)[J];中國(guó)藥理學(xué)通報(bào);2011年01期

2 左之才;鄧俊良;王哲;張乃生;李艷飛;牛淑玲;李紅梅;劉彩霞;;不同能量攝入水平對(duì)圍產(chǎn)期健康奶牛血清總膽紅素、蛋白及轉(zhuǎn)氨酶的影響[J];中國(guó)獸醫(yī)學(xué)報(bào);2007年06期

3 GRUYS E.,TOUSSAINT M.J.M.,NIEWOLD T.A.,KOOPMANS S.J.;Acute phase reaction and acute phase proteins[J];Journal of Zhejiang University Science;2005年11期

，

本文編號(hào)：2207328