【作者】 郑智勇；

【导师】 周杰；

【作者基本信息】 安徽农业大学 ， 基础兽医学， 2008， 硕士

【摘要】 皖西白鹅是我国优良的中型鹅品种之一。它主要分布于安徽省的皖西山区及河南省的固始县,属国家二类禽类保护动物,并确定为“国家级畜禽品种资源保护”品种。本试验通过研究在粗饲条件下与世界公认的优秀品种朗德鹅所表现的生长和生产性能的比较,评价皖西白鹅的品种特点,探索其肝脏和肌肉的生长调节机理。试验动物选自安徽省皖西白鹅保种基地,皖西白鹅、朗德鹅各半,共计340只。饲养于安徽省六安市皖西白鹅保种基地。所有鹅只混合饲养,自由采食、饮水。参考皖西白鹅的最佳饲养标准。实验动物日粮标准设计如下:1～28 d代谢能为11.58MJ/kg,粗蛋白为18.16%;29～70d代谢能为10.99MJ/kg,粗蛋白为13.68%。29～56d草料比为3:1,57～90d草料比为1:1饲养至90日龄屠宰,随机选取皖西白鹅和朗德鹅各20只(公母各半)。屠宰前禁食12 h。拔毛后称得屠体重。血液样品的采集:翅静脉采血。组织样品的采集:迅速采出鹅的肝脏和胸肌组织块放在2ml离心管中,立即置于液氮中。测定的屠宰指标有屠体重、半净膛、全净膛、全净膛率、肝脏重、肝重率、胸肌重、胸肌率。按照国标方法测定胸肌中肌间脂肪含量。使用半自动生化分析仪测定血清中甘油三酯(TG)、总胆固醇(TCHO)、高密度脂蛋白(HDL-C)、低密度脂蛋白(LDL-C)水平;采用SN-695B型智能放免γ测量仪测定血清中胰岛素(INS)水平、游离T3、T4水平。用相对定量RT-PCR方法测定肝脏组织和肌肉组织中生长激素受体(GHR)、胰岛素样生长因子1(IGF-1)及胰岛素样因子1受体(IGF-1R)mRNA表达水平。实验结果如下:(1)在粗饲条件下,90日龄的皖西白鹅肝脏重和肝重率高于朗德鹅,并且达到极显著水平(p＜0.01);体重、半净膛、全净膛、全净膛率、胸肌重、胸肌率等屠宰指标皖西白鹅与朗德鹅并无显著差异。(2)皖西白鹅胸肌肌间脂肪含量高于朗德鹅,并且达到极显著水平(p＜0.01);而在两品种鹅的公母间没有显著差异(p＞0.05)。(3)皖西白鹅的血清中TG、TCHO、HDL-C含量高于朗德鹅,并且达到显著水平(p＜0.05),血清中LDL-C含量公母间差异不显著;朗德鹅血清中LDL-C和HDL-C含量在公鹅极显著高于母鹅(p＜0.01)。(4)两种鹅血清中游离T3水平并没有显著差异,而皖西白鹅血清中T4水平极显著高于朗德鹅(p＜0.01)。两种鹅血清中胰岛素(INS)水平没有显著差异。(5)皖西白鹅和朗德鹅肝脏中的GHR mRNA相对β-actin的表达量分别为0.93±0.05,0.91±0.05,无显著差异。皖西白鹅组IGF-1mRNA相对β-actin的表达量(1.00±0.04)极显著高于朗德鹅组(0.78±0.04),(p＜0.01)。皖西白鹅和朗德鹅肝脏中IGF-1R的mRNA相对β-actin的表达量分别为0.81±0.07和0.83±0.07,没有显著差异。(6)皖西白鹅和朗德鹅胸肌组织中的GHR mRNA相对β-actin的表达量分别为0.82±0.05,0.84±0.05,无显著差异。皖西白鹅和朗德鹅胸肌组织中IGF-1mRNA相对β-actin的表达量分别为0.79±0.04,0.77±0.04,无显著差异。皖西白鹅和朗德鹅胸肌组织中IGF-1R的mRNA相对β-actin的表达量分别为0.82±0.07,0.82±0.07,也没有显著差异。(7)朗德鹅血清中TG和HDL-C、LDL-C、TCHO含量以及肝重率间均呈极显著正相关(p＜0.01);TCHO和LDL-C、HDL-C含量间分别呈高度极显著正相关(p＜0.01);LDL-C和HDL-C含量间呈高度极显著正相关(p＜0.01)。(8)鹅体重与肝脏重相关(r=0.35,p＜0.05),体重与胸肌重显著相关(r=0.79,p＜0.01)。肝重率与肝脏组织中IGF-1的mRNA的丰度显著相关(r=0.67,p＜0.01)。胸肌重与胸肌组织中IGF-1的mRNA的丰度显著相关(r=0.57,p＜0.05)。结论:在粗饲条件下,皖西白鹅与朗德鹅在肝脏重和肝重率方面有显著差异(p＜0.01),而在其它屠宰指标方面没有显著差异;皖西白鹅与朗德鹅在血脂代谢方面存在种间差异;推测鹅肝脏和胸肌组织自分泌的IGF-1在对其生长调节其主要作用。更多还原

【Abstract】 Wanxi White Goose is a superordinary middle-typed goose.It mainly located in mountainous areas in the west of Anhui Province and Gushi County in Henan Province.It was identified as the country second class protected poultry and "national-level animal species resources Protection variety".In this study,growth characteristics of Wanxi geese were estimated by compared with production traits of Landaise Geese,which were received as an excellent variety all over the world,were expressed under crude fed.The test animal came from Wanxi white geese breed-conservation base in AnHui province,including 170 Wanxi white geese and 170 Langdaise geese.All the geese were fed together,ate and drank freely.Making reference to the best feeding standard,the diet for the test animal was designed as follows:metabolizable energy was 11.58MJ/kg and the crude protein was 18.16%during 1-28d;matabolizable energy was 10.99MJ/kg and the crude protein was 13.68%during 29-70d.The forage ratio was 3:1 from 29 to 56d,1:1 from 57 to 90d.20 Wan-xi white geese and 20 Langdaise geese each were chosen randomly to be sacrificed(half males and half females) after 12 hours fasting.Blood samples were collected via wing vein.The liver and pectoral muscle were put into 2ml centrifuge tube and preserved in fluid nitrogen.And the following slauger index should be detected including dressed weight,half-eviscerated weight,eviscerated weight,eviscerated weight index,liver weight,liver index,pectoral muscle weight and pectoral muscle index. Intramuscular fat was tested by the national standard method.The semi-automatic biochemical analyzer was used to test serum triglyceride(TG),total cholesterol(TCHO), high-density lipoprotein cholesterol(HDL-C),low-density lipoprotein cholesterol (LDL-C).The smart-SN-695B RIAγ,measuring instrument was used to test insulin(INS), free Triiodothyronine(T3),free Thyroxine(T4) level in serum.The total RNA was extracted from liver and muscle to measure the abundance of the growth hormone receptor (GHR),insulin like growth factor-1(IGF-1) and insulin like growth factor-1 receptor (IGF-1R) by Semi-quantitative RT-PCR usingβ-actin as an internal standard.The results are as follows:(1)In rough feeding conditions,the 90-day-old Wanxi White Geese liver and liver weight-rate were significantly higher than that of Langdaise Geese(p<0.01);But Dressed weight,Half-eviscerated weight,Eviscerated weight,Eviscerated weight Index,Pectoral Muscle weight,Pectoral Muscle index there was no significant difference between two breeds.(2) Intramuscular fat content in pectoral muscle of Wanxi White Geese was significantly higher than that of Langdaise Geese(p<0.01);Intramuscular fat content was no significant sex difference in two varieties(p>0.05).(3) Plasma TG,TCHO,HDL-C were exactly higher in Wanxi White Geese than those in Landaise Geese(p<0.01);in Langdaise Geese serum,levels of LDL-C and HDL-C there was a significant sex difference(p<0.01).(4) Plasma free T3 and INS were no significant difference between two varieties.The level of free T4 in Wanxi White Geese was exactly higher than that in Landaise Geese(p<0.01)(5) IGF-1 mRNA expression was higher in Wanxi White Geese(1.00±0.04) than that in Landaise Geese(0.78±0.04)(p<0.01).GHR and IGF-1R mRNA expression were no significantly different between Wanxi White Geese(0.93±0.05,0.81±0.07) and Landaise Geese(0.91±0.05,0.83±0.07)(p>0.05).(6).In Pectoral muscle,GHR,IGF-1 and IGF-1R mRNA expression were no significant difference between Wanxi White Geese(0.82±0.05,0.79±0.04,0.82±0.07) and Landaise Geese(0.84±0.05,0.77±0.04,0.82±0.07)(p>0.05).(7) Significant positive correlation was found among plasmaTG,TCHO,HDL-C in both of tow breeds.And significant positive correlation was also found between liver index and plasma TG in Landaise Geese.(8) Significant positive correlation was found between body weight and liver weight (r=0.35,p<0.05).The liver index with the expression of IGF-1mRNA in liver also had significant positive correlation(r=0.67,p< 0.O1 ).Significant positive correlation was found between body weight and Pectoral muscle weight(r=0.79,p<0.01 ).The Pectoral muscle weight with the expression of IGF-1 mRNA in Pectoral muscle also had significant positive correlation(r=0.57,p<0.05)Conclusion:under rough feeding conditions,there was a significant difference between two breeds only in the liver weight and liver index(p<0.01);In two breeds,it is resemble in metabolic mechanism of cholesterol but significant difference in the growth of liver and metabolic mechanism of TG;autocrine of IGF-1 maybe play an important role during the growth of liver and muscle in Geese.更多还原