摘要
本试验旨在通过探讨饲粮叶酸水平对1～15周龄鹅生长性能、血清生化指标和酶活性及肝脏亚甲基四氢叶酸还原酶(MTHFR)基因表达量的影响,以确定在育雏期(1～4周龄)、育成期(5～15周龄)鹅饲粮中叶酸的适宜添加水平。试验选用1日龄青农灰鹅360只,随机分为6个组,每组6个重复,每个重复10只鹅。试验鹅分别饲喂在基础饲粮中添加0(对照组)、1、2、4、8、16 mg/kg叶酸的试验饲粮。试验期15周。结果表明:1)饲粮添加叶酸能显著或极显著提高1～4周龄鹅平均日增重(P<0.05或P<0.01),显著降低1～4周龄鹅料重比(P<0.05),降低死淘率。2)饲粮添加叶酸能显著降低1～4周龄鹅血清葡萄糖含量(P<0.05),显著提高1～4周龄鹅血清甘油三酯含量(P<0.05)。饲粮添加8 mg/kg叶酸可显著降低1～4周龄鹅血清尿素氮含量(P<0.05);添加16 mg/kg叶酸可显著降低5～15周龄鹅血清尿素氮含量(P<0.05)。饲粮添加2～16 mg/kg叶酸可显著降低1～4周龄和5～15周龄鹅血清同型半胱氨酸含量(P<0.05)。3)饲粮添加1、2 mg/kg叶酸可显著提高1～4周龄鹅血清MTHFR活性(P<0.05),显著降低血清二氢叶酸还原酶(DHFR)活性(P<0.01,P<0.05),添加2 mg/kg叶酸可显著降低血清谷草转氨酶和乳酸脱氢酶活性(P<0.05)。饲粮添加2 mg/kg叶酸可显著提高5～15周龄鹅血清M THFR活性(P<0.05)。4)1～4周龄,MTHFR基因表达量与M THFR活性显著正相关(P<0.05),与DHFR活性显著负相关(P<0.05);5～15周龄,MTHFR基因表达量与MTHFR和谷丙转氨酶活性显著负相关(P<0.05)。由以上结果可知:1)根据生长性能建立的回归方程得出,建议鹅饲粮中育雏期叶酸添加水平为2.45 mg/kg,育成期添加水平为2.08 mg/kg;添加叶酸可降低死淘率;2)叶酸水平对鹅血清生化指标和酶活性有重要的调控作用;3)叶酸对鹅肝脏中MTHFR基因的表达量有直接影响,MTHFR基因表达量与MTHFR、DH-FR和谷丙转氨酶活性密切相关。
This experiment was conducted to study the effects of dietary folic acid level on growth perform- ance, serum biochemical parameters and enzyme activity and methylenetetrahydrofolate reductase （MTHFR） gene expression of geese, and to determine the folic acid optimum supplemental level of geese aged 1 to 4 weeks （brooding period） and 5 to 15 weeks （finishing period）. Three hundred and sixty 1-day-old Qingnong- hui geese were randomly selected and divided into 6 groups with 6 replicates per group and 10 geese per repli- cate. Geese in the six groups were fed the basal diet supplemented with 0 （control）, 1, 2, 4, 8 and 16 mg/kg folic acid, respectively. The experiment lasted for 15 weeks. The results showed as follows： 1 ） di- etary folic acid significantly increased average daily weight gain of geese aged 1 to 4 weeks and 5 to 15 weeks （ P 〈 0.05, P 〈 0.01 ） , significantly decreased feed to gain of geese aged 1 to 4 weeks （ P 〈 0.05 ）, and re- duced mortality rate. 2） Dietary folic acid significantly decreased serum glucose content of geese aged 1 to 4 weeks （ P 〈 0.05 ）, and significantly increased serum triglyceride content （ P 〈 0.05 ）, and the supplementa- tion of 8 mg/kg folic acid significantly decreased serum urea nitrogen content （P 〈 0.05 ）. The supplementa- tion of 16 mg/kg folic acid significantly decreased serum urea nitrogen content of geese aged 5 to 15 weeks （ P 〈 0.05 ）. The supplementation of 2 to 16 mg/kg folic acid significantly decreased serum homocysteic acid content of geese aged 1 to 4 weeks and 5 to 15 weeks （P 〈 0.05 ）. 3 ） The supplementation of 1 and 2 mg/kg folic acid significantly increased serum MTHFR activity of geese aged 1 to 4 weeks （P 〈 0.05 ）, and signifi- cantly decreased serum dihydrofolate reductase （DHFR） activity （P 〈 0.01 or P 〈 0.05 ）, and the supplemen- tation of 2 mg/kg folic acid significantly decreased serum glutamic-oxaloacetic transaminase and lactate dehy- drogenase activity （ P 〈 0.05 ）. The supplementation of 2 mg/kg folic acid significantly increased serum MTH- FR activity of geese aged 5 to 15 weeks （P 〈 0.05 ）. 4 ） In the brooding period, the MTHFR gene expression was significantly positive correlation with MTHFR activity （ P 〈 0.05 ）, and significantly negative correlation with DHFR activity （ P 〈 0.05 ）. In the finishing period, the MTHFR gene expression was significantly nega- tive correlation with MTHFR and glutamic pyruvic transaminase activity （ P 〈 0.05 ）. It is conclusion that： 1 ） according to the regression equation between growth performance and dietary folic acid level, the suggestion of optimum dietary folic acid level is 2.45 mg/kg in brooding period, and 2.08 mg/kg in finishing period. Diet- ary folic acid can decrease mortality rate. 2 ） Dietary folic acid level has an important role in the regulation of serum biochemical parameters and enzyme activity. 3 ）Folic acid has a direct impact on MTHFR gene expres- sion in geese liver, and MTHFR gene expression is closely related to the activities of MTHFR, DHFR and glu- tamic pyruvic transaminase.
出处
《动物营养学报》
CAS
CSCD
北大核心
2013年第5期985-995,共11页
CHINESE JOURNAL OF ANIMAL NUTRITION
基金
国家水禽产业技术体系专项基金(CARS-43-11)
关键词
叶酸
鹅
生长性能
血清生化指标
酶活性
MTHFR基因表达量
folic acid
geese
growth performance
serum biochemical parameters
enzyme activity
MTHFRgene expression
