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1.
一次注射法适宜采血时间的确定   总被引:1,自引:1,他引:1  
给绝食、强饲无氮日粮 (NFD)、分别以豆粕或棉粕为唯一氮源的CP2 0 %半合成饲粮的蛋青鸡 ,静脉一次注射 3 0 μCi3H Leu/kgBW ,于注射后 5、3 0min、4、2 4、3 6、48h翅静脉采血 ,测定各时间点的去蛋白血浆比放射性强度及 48h内排泄物的比放射性强度。通过定积分分析 ,一次静脉注射法检测内源氨基酸损失量的适宜采血时间为注射3H Leu后 2 0~2 4h。  相似文献   

2.
选取2 8日龄、体重相近的合浦灰鹅6 0只,随机分为3组,每组2 0只(1 0公,1 0母),饲粮(精料)粗蛋白质(CP)分别为12.50%(第1组),15.80%(第2组)和17.83%(第3组)。采用精料 青料(黑麦草等)混合方式饲喂,进行两阶段为期42 d的饲养试验。5周龄和9周龄时从饲养试验3个组中各选取4只体重接近的试鹅,测定鹅对饲粮(精料 青料)养分的代谢率。结果表明:(1)生长前期(28~49日龄),第2组日增重较高,但组间差异不显著;饲粮粗脂肪(EE)、中性洗涤纤维(NDF)、半纤维素和无氮浸出物(NFE)的代谢率显著高于其他两组(P<0.05)。(2)生长后期(50~70日龄)第1组日增重较高,但组间差异不显著;干物质(DM)、CP、EE的代谢率显著高于其他两组(P<0.05);粗纤维(CF)代谢率显著高于第2组(P<0.05)而与第3组无显著差异。(3)血清尿素氮含量随饲粮CP水平的降低而下降(P<0.05);血清转氨酶活性、脂类和脂蛋白含量等组间无显著差异;(4)饲粮粗蛋白质水平对肉鹅屠宰性能无显著影响。  相似文献   

3.
一次注射3H-Leu测定肉仔鸡内源氨基酸排泄量的方法学研究   总被引:2,自引:1,他引:1  
给强饲无氮饲粮(NFD),NFD+3.20%酶解酪蛋白(EHC),以豆粕为唯一氮源粗蛋白(CP)为5%及20%半合成饲粮的肉仔鸡,静脉注射30μCi/kg体重^3H-Leu注射后5min,4h,24h,36h及48h测定血浆游离Leu比放射性强度(SRp)及48h内排泄物比放射性强度(SR)。结果表明,不同饲粮排泄物内源Leu比放射性强度(SRe)与SRp定积分值与之比恒等,证明我们提出的一次注射  相似文献   

4.
选择平均体重约3 0 kg的杜长大三元杂交断奶仔猪70头,随机分成对照组和试验 、 、 、 组,进行为期86d (生长期3 3 d,肥育期5 3 d)的饲养试验。试验处理为:对照组全期饲粮不用糖蜜酒精废液蔗渣吸附发酵产物( MABFP) ,试验 、 、 、 组生长期饲粮分别使用2 %、4%、6%和8%的MABFP;肥育期饲粮分别使用4%、8%、1 2 %和1 6%的MABFP。每期的试验组和对照组均为等能等蛋白质饲粮。饲养试验结果表明:生长期,试验各组的日增重和饲料效率与对照组无显著差异( P>0 .0 5 ) ;肥育期,试验 、组日增重与对照组无显著差异( P>0 .0 5 ) , 、 组日增重低于对照组( P<0 .0 5 ) ;肥育期以及试验全期各试验组饲料效率有所降低。血清生化指标及胴体品质的分析结果表明:生长肥育猪饲粮使用MABFP,对猪血清生化指标、组织器官生理功能、肉猪胴体指标和猪肉品质等无不良影响。综上所述,MABFP可做生长肥育猪配合饲料的原料,建议其用量以6%~8%为宜,同时注意适当补充必需氨基酸  相似文献   

5.
华东地区粉煤灰农田模拟试验和放射性分析   总被引:6,自引:0,他引:6  
史建君  徐寅良 《核农学报》2002,16(4):212-216
对浙江、福建、山东、江西、安徽和江苏 6省部分大型热电厂粉煤灰的采样分析表明 :粉煤灰中主要放射性成分为2 38U、2 32 Th衰变系和4 0 K ,比活度范围分别为 75~2 84Bq kg、60~ 1 64Bq kg和 1 2 0~ 73 8Bq kg。粉煤灰农田施用模拟试验表明 :当施用量达到 52 5t hm2 时 ,土壤中天然放射性核素2 2 6 Ra和2 2 8Ra的比活度分别是对照的 1 88倍和 1 3 9倍 ;生产的食品 (稻谷、玉米籽和麦粒 )中 2种核素的比活度与对照没有明显差异 ,对作物的食用安全性影响不明显  相似文献   

6.
采用3×3拉丁方试验设计,选用3头安装有永久性瘤胃、十二指肠近端瘘管和颈静脉插管,平均体重为20kg±2.5kg的健康湘东黑山羊为试验动物,饲喂Met水平分别为0.15%、0.25%和0.35%的3种试验日粮,旨在研究Met水平对山羊内源氮(EN)和内源氨基酸(ENAA)流量的影响,同时比较差量法和同位素稀释法测定山羊十二指肠EN和ENAA流量的差异。结果显示:日粮Met水平对山羊十二指肠EN和ENAA流量没有显著影响(P0.05);当日粮Met水平为0.15%时,差量法和同位素稀释法测定十二指肠EN和ENAA流量均最低,且2种测定方法之间无显著差异(P0.05);差量法测定EN和ENAA流量均低于同位素稀释法测定结果(P0.05)。结果表明:山羊十二指肠EN和ENAA流量不受日粮Met水平影响;差量法测定的十二指肠EN和ENAA流量低于同位素稀释法。  相似文献   

7.
为探究富含不饱和脂肪酸的过瘤胃脂肪对肉牛营养物质消化代谢和氮沉积的影响,本研究选用4头体重476±60 kg、年龄4.5岁、装有永久性瘤胃瘘管的晋南阉牛,以精补料和玉米青贮为基础饲粮,饲粮蛋白质按照1.15倍的维持营养需要量的85%(低)、100%(中)和115%(高)设计3个水平,并在此基础上添加干物质采食量的0%、2.5%、5.0%和7.5%的过瘤胃脂肪,采用3×4两因素设计,共形成12组饲粮组合,测定养分消化率、氮沉积率和血液生化指标。结果表明,第8组饲粮粗蛋白质(CP)的表观消化率极显著高于第2组、显著高于第3和第4组,第7和第10组显著高于第2组;第4、第7、第8、第11和第12组粗脂肪(EE)的表观消化率极显著高于第1、第2、第5、第9组,第3、第6和第10组显著高于第1、第2、第5、第9组;第8和第10组无氮浸出物(NFE)的表观消化率显著高于第11组;第8组中性洗涤纤维(NDF)的表观消化率显著高于第11组。第1、第5、第6、第8和第11组的氮沉积率显著高于第12组。第10组三酰基甘油酯酶(ATGL)活性显著高于第6组;第3、第4、第5、第2和第7组的胰岛素(INS)浓度极显著高于第8组;第1和第2组的胰高血糖素(GC)浓度显著高于第9和第11组;第7组的生长激素(GH)浓度显著高于第2、第4、第5、第9、第10和第11组。综上,在以饲粮蛋白质水平为标准前提下,过瘤胃脂肪适宜添加量为饲粮的5.0%。本研究为肉牛养殖和高档肉牛生产提供了一定的理论依据。  相似文献   

8.
选用体重约3 0kg的杜×长×大三元杂生长猪9 6头,随机分成4个处理组,每组6个重复,每重复4头,公母比为1∶1。A组为对照组,饲喂基础饲粮,B、C、D组为试验组(分别以2 5 0、5 0 0、750 U植酸酶/kg饲粮取代基础饲粮中的40%、60%、80%磷酸氢钙),以研究玉米豆粕型饲粮中添加植酸酶对生长猪生长性能和血液生化指标的影响。42 d的饲养试验结果表明:与对照组相比,B、C、D组的日增重分别提高了1.05%(P>0.05)、4.09%(P<0.05)、2.64%(P>0.05);饲料/增重比分别较对照组降低了2.18%、2.62%、1.75%;生长增重的饲料成本分别是对照组的97.38%、97.03%和97.73%;血清中钙含量分别提高了4.22%、4.22%、8.12%(P<0.05);血清中磷含量分别提高了1.46%、0.36%、14.23%(P<0.05),其他生化指标组间无明显差异。  相似文献   

9.
农牧结合生态工程是个复杂的农业生态、经济和技术系统工程,它由植物(种植业)、动物(养殖业)和微生物(连接种养业)3个子系统组成,其关键是建设以“四三二一”畜牧业生产模式为主要内容的高效节粮型畜牧业生态工程。农牧结合种植结构主要模式有“一粮一饲”、“一粮一经”、“两饲一粮”和“一粮一经一饲”等多种模式。农牧结合型种植模式的核心是因地制宜建立以粮食生产为基础,饲料生产为重点,经济作物生产为动力,并有机配合和协调发展粮-经-饲三元种植新模式,3种作物种植参考比例为5∶2∶3。  相似文献   

10.
为了解肉牛舍安装接力送风和饲粮中添加烟酸铬对肉牛生长性能、肉牛生理和牛舍环境的影响,研究了南方夏季安装接力送风机和饲粮添加铬对拴系敞篷饲养肉牛舍热环境及对肉牛日增质量的影响。试验采用双因素设计,选取36头平均体质量为392.8 kg的西杂肉牛,随机分成4个处理,处理1组牛舍安装风机,并在饲粮中添加烟酸铬;处理2安装风机,饲粮中不添加烟酸铬;处理3组不安装风机,但饲粮中添加烟酸铬;处理4(对照组)不安装风机,不添加烟酸铬。铬的添加量为800μg/kg,进行为期30 d生长试验。试验分别测定了牛舍的环境指标、肉牛生理指标和肉牛日增质量,并对经济效益进行了分析。结果如下:1安装接力送风机牛舍14:00平均室温可降低1.9℃(P0.01),风速增加5.6倍(P0.01),降低温湿指数(temperature and humidity index,THI)5.65%(P0.01);2饲粮添加铬降低热应激肉牛呼吸频率2.37次/min(P0.01),降低直肠温度0.18℃(P0.01),安装风机降低呼吸频率6.97次/min(P0.01),安装风机和饲粮添加铬对肉牛呼吸频率和直肠温度无交互作用。3处理1组肉牛平均日增质量比处理2、处理3和对照组分别提高了44.16%(P0.05)、35.37%(P0.05)和79.03%(P0.05)。处理2组和处理3组比对照组平均日增质量提高了24.19%(P0.05)和32.26%(P0.05)。处理1组比对照组增加毛利8.72元/(头·d)。表明南方夏季肉牛舍安装风机和饲粮中添加铬800μg/kg均缓解了肉牛湿热应激,提高了平均日增质量和经济效益,二者结合使用效果较好。  相似文献   

11.
The effect of hydrolyzed casein (HC) on the expression of three mucin genes (Muc2, Muc3, and Muc4) in the rat intestine was investigated using quantitative real-time polymerase chain reaction. After a 10 day acclimatization period, rats received for 8 days the test diets containing either HC or a synthetic amino acid (SAA) mixture as the sole source of nitrogen or a protein-free (PF) diet (n = 12 per treatment). The addition of HC or the SAA mixture to the diet significantly improved average daily gain, average daily food intake, and gain:feed ratio as compared with the PF diet. Terminal ileal endogenous N flow was significantly higher for the HC-fed rats in comparison with either the SAA or the PF rats (p < or = 0.001). HC supported a significant increase of Muc3 mRNA (277 and 229% of that for diets PF and SAA, respectively; p < or = 0.05) in the small intestinal tissue and Muc4 mRNA (325 and 265% of that for diets PF and SAA, respectively; p < or = 0.05) in the colon. In conclusion, HC enhances ileal endogenous N flow and up-regulates in vivo the expression of some individual mucin genes.  相似文献   

12.
The nutritional effects in the rat of raw lentil meal or its fractions have been evaluated in three feeding trials. Growth, gain/feed ratio, apparent N digestibility, and N retention were significantly (p < 0.05) reduced by the inclusion of whole lentil meal, dehulled lentil meal, or ethanol-extracted lentil meal as the sole source of protein in the diet. Pure lentil lectin and lectin-depleted albumin proteins had no significant negative effect on nutritional performance. In contrast, growth, gain/feed ratio, protein conversion efficiency, N digestibility, and N retention were significantly (p < 0.05) reduced by diets containing lentil globulins or lentil hulls. The poor nutritional quality of raw lentil meal for rats is therefore likely to be primarily due to the combined effects of these two components.  相似文献   

13.
Tilapia is a warmwater fish with mild flavor. Nearly 8.6 million kg are produced domestically, and ≈22.7 million kg are imported. Corn gluten meal (60% protein fraction) is a product obtained from wet-milling of corn. Diets (36% protein) containing 36–44% corn gluten meal with different levels of lysine and fish meal were formulated and fed to tilapia in aquaria for 12 weeks. Weight gain (WG) of tilapia fed diets containing the highest level of lysine (7.4% protein) with 4% fish meal was equal to that of fish fed a commercial control diet. Diets with lower lysine resulted in lower WG. The feed conversion ratio (FCR) and protein efficiency ratio (PER) of tilapia fed experimental diets containing adequate levels of essential amino acids and fish meal were the same as for fish fed the commercial control diet (also containing fish meal). Fish fed diets containing lower lysine levels had less favorable FCR and PER. This study shows that corn gluten meal is utilized at high levels in tilapia diets, particularly if essential amino acids are provided in adequate amounts.  相似文献   

14.
A recently developed assay for determining available lysine (true ileal digestible reactive lysine) in foods and feedstuffs was applied to 20 commercially available cat foods. Semisynthetic diets, containing cat food as the sole protein source, were prepared. Titanium dioxide was included as an indigestible marker. The diets were fed to growing rats and digesta from the terminal ileum collected and analyzed, along with the diets, for reactive lysine. True reactive lysine digestibility was determined after correction for endogenous lysine loss at the terminal ileum of rats fed an enzyme-hydrolyzed casein-based diet. The amounts of digestible total lysine (conventional method) were also determined. Ileal total lysine digestibility significantly (P<0.05) underestimated (3.6-10.2%) lysine availability (ileal reactive lysine digestibility) for most of the cat foods tested. Ileal digestible total lysine significantly (P<0.05) overestimated the amount of dietary available lysine for all of the cat foods tested by between 38 and 143%. Total lysine digestibility determined using the conventional method of lysine analysis was inaccurate when applied to commercially available cat foods.  相似文献   

15.
A commercial, high-glucosinolate, rapeseed meal with no added salt or mixed with 2, 5, or 10% NH4HCO3 was extruded under different processing conditions using the Wenger TX-52 twin-screw extruder. Male Wistar rats were fed 13 diets containing 15% rapeseed meals (including nonextruded) or a casein-based control diet. After six weeks, blood samples were taken, and serum was analyzed for thyroid hormones. Extrusion processing under all salt and steam conditions tested reduced glucosinolate levels in the meal, but no significant correlation was found between intensity of the treatment conditions and glucosinolate reduction. Higher weight gains, feed efficiencies, and thyroid hormone profiles were observed with use of the extruded meals; but no treatment completely detoxified the meal. Histopathological evaluation showed that thyroid and other tissue abnormalities occurred in all animals except those fed the casein diet. Antinutrients, including glucosinolates and probably volatile nitriles, in the meal were reduced by extrusion processing under the basic conditions of this experiment.  相似文献   

16.
The nutritional effect of diet containing decorticated sesame seed extracted with isopropanol (DSS-Iso) was evaluated on growth performance, food efficiency ratio, plasma and tissue lipid profile, plasma protein content, and erythrocyte membrane lipid profile of rats on a comparative basis with diets containing casein (control), soybean meal, and decorticated sesame seed extracted with hexane (DSS-Hex). Rats fed a DSS-Iso-based diet showed body weight gain and food efficiency ratio similar to those of the control groups fed diets prepared with casein, soybean meal, and DSS-Hex. However, dietary proteins exerted a separate effect on plasma lipid concentrations of the rats. Rats fed a DSS-Iso-based diet showed significant decreases in plasma total cholesterol (p < 0.01), triglyceride (p < 0.01), and VLDL+LDL cholesterol (p < 0.01) concentrations in comparison to the rats fed diet containing casein. No significant differences in plasma lipid concentrations were observed for the rats fed diets prepared with soybean meal, DSS-Hex, and DSS-Iso. Rats fed the different dietary proteins did not show much variation in plasma proteins, liver lipids, and erythrocyte membrane lipid concentrations, which suggests that DSS-Iso could be a suitable edible protein like casein or soybean meal.  相似文献   

17.
The aim was to determine the fate of transgenic and endogenous plant DNA fragments in the blood, tissues, and digesta of broilers. Male broiler chicks (n = 24) were allocated at 1 day old to each of four treatment diets designated T1-T4. T1 and T2 contained the near isogenic nongenetically modified (GM) maize grain, whereas T3 and T4 contained GM maize grain [cry1a(b) gene]; T1 and T3 also contained the near isogenic non-GM soybean meal, whereas T2 and T4 contained GM soybean meal (cp4epsps gene). Four days prior to slaughter at 39-42 days old, 50% of the broilers on T2-T4 had the source(s) of GM ingredients replaced by their non-GM counterparts. Detection of specific DNA sequences in feed, tissue, and digesta samples was completed by polymerase chain reaction analysis. Seven primer pairs were used to amplify fragments ( approximately 200 bp) from single copy genes (maize high mobility protein, soya lectin, and transgenes in the GM feeds) and multicopy genes (poultry mitochondrial cytochrome b, maize, and soya rubisco). There was no effect of treatment on the measured growth performance parameters. Except for a single detection of lectin (nontransgenic single copy gene; unsubstantiated) in the extracted DNA from one bursa tissue sample, there was no positive detection of any endogenous or transgenic single copy genes in either blood or tissue DNA samples. However, the multicopy rubisco gene was detected in a proportion of samples from all tissue types (23% of total across all tissues studied) and in low numbers in blood. Feed-derived DNA was found to survive complete degradation up to the large intestine. Transgenic DNA was detected in gizzard digesta but not in intestinal digesta 96 h after the last feeding of treatment diets containing a source of GM maize and/or soybean meal.  相似文献   

18.
Metabolic engineering was applied to the development of Escherichia coli capable of synthesizing tyrosol (2-(4-hydroxyphenyl)ethanol), an attractive phenolic compound with great industrial value, from glucose, a renewable carbon source. In this strain, tyrosine, which was supplied not only from the culture medium but also from the central metabolism, was converted into tyrosol via three steps: decarboxylation, amine oxidation, and reduction. The engineered strain synthesized both tyrosol and 4-hydroxyphenylacetate (4HPA), but disruption of the endogenous phenylacetaldehyde dehydrogenase gene shut off 4HPA production and improved the production of tyrosol as a sole product. The engineered mutant strain was capable of producing 0.5 mM tyrosol from 1% (w/v) glucose during a 48 h shake flask cultivation.  相似文献   

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