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1.
利用二次回归正交旋转组合设计方法研究了外源性环核苷酸(CNT)对商品代AA肉鸡增重影响及最佳应用时间,探讨了cAMP,cGMP与时间是互作关系,建立了数学模型,获得了最佳CNT用量及最佳应用时间。外源性CNT及应用时间对AA肉鸡体重影响的数学模型为:y=2.3859-0.0109x1+0.0145x23-0.。0114x3+0.0550x1x2+0.0150x1x3+0.0375x2x3=0.05  相似文献   

2.
采用聚丙烯酰胺凝胶电泳法对71头互助白牦牛4种血液蛋白质的多态性进行研究。结果表明:(1)血红蛋白显著HBF^+S^-,HB FS和HBF^-^S+三种表型,其表型频率分别为4.3%,94.3%和1.4%;(2)血清白蛋白、血清运铁蛋白和血清亲血色蛋白均呈单态,显现单一的ALBAA,TFDD和Hpl-1型;(3)互助白牦牛4种血液蛋白质的Ppoly为25.0%,H为0.0273。  相似文献   

3.
利用二次回归通用旋转组合设计方法研究了复合酶制剂对猪日增重的影响,探讨了α-淀粉酶,中性蛋白酶和脂肪酶之间的互作关系,建立了数学模型,确定了酶制剂的最佳使用剂量。复合酶制剂对日增重影响的函数模型为:Y=534.6772+22.9541X1+8.1627X2+3.2795X3-1.6125X1X2+17.3125X1X3+6.0375X2X3+8.8555X1^2-2.7587X2^2+4.3124  相似文献   

4.
将狂犬病病毒糖蛋白cDNA BglⅡ(1.67kb)片段正向插入pMT010/A^+BamHⅠ切点,构建重组质粒pMT010/A^+-Rgp,用EcoRⅠ+SalⅠ对pMT010/A^+-Rgp进行双酶切后,回收含有狂犬病病毒糖蛋白cDNA和绵羊MT启动子的2.76kb片段,通过显微注射技术将该片段注入小鼠单细胞受精卵雄前核内,在进行胚胎移植后,获得44只小鼠,经PCR、Southern杂交及原位  相似文献   

5.
冷地早熟禾种子生产的优化栽培技术研究   总被引:2,自引:0,他引:2  
采用3因素5水平二次回归正交组合设计试验,建立了冷地早熟种子产量(Y)与播种量(X1)、行距(X2)和施肥量(X3)的回归方程:Y=42.61+5.01X1-7.81X2+7.77X3=2.21Z1X2+1.41X1X3-0.41X2X3=4.64X1^2+6.36X2^2+8.56X3^2;并提出西宁地区冷地早熟禾种子生产的优化农艺措施,播咎量8kg/hm^2,播种行距20-30cm,种肥150  相似文献   

6.
采用BSG法对新一之濑和育2号优质种质资源的Giemsa-C带的诱导及带型分析表明,新一之濑的带型公式为2n=28=2CIT+1T^++1CIT+T^-+1IT+3CT^+T+2CI+2C+I,育2号为2n=28=2CIT+1CT+1T+2CIT+1T+4CT^+-+i+2ci+2c+I,2品种特征以着丝粒带(C)为主,其次为端带和中间带,2个桑品种未发现无带现象。断一之濑第4、8、10、14带纹  相似文献   

7.
白唇鹿血清生化指标测定   总被引:4,自引:1,他引:3  
测定了35头青海白唇鹿的19项血清生化指标。结果为Na^2+138.1±5.84mmol/L,K^+5.75±0.73mmol/L,Ca^2+2.42±0.20/L,P2.33±.38mmol/,Cl^-,102.2±6.03mmol/L,总蛋白87.50±6.17g/L白蛋白59.18±6.96g/L球蛋白28.34±5.26g/L,A/G,2.19±0.59,血清蛋白质组分(%)A67.57±  相似文献   

8.
环核苷酸(CNT)在豚鼠体内代谢规律的研究   总被引:3,自引:0,他引:3  
以豚鼠为实验动物,了^3H-cAMP、^3H-cGMP在动物体仙的转运与代谢规律,其示踪动力学模型可用于C=1229.5131e^=0.035lt+52.5227e^-0.0350t-1282.0368^-3.0878t,Ct=1276.4643e^-0.0364t+18.9551e^=0.0363t=1295.4194e^-3.2044t一级吸收二室模型来描述。研究还证明,cAMP、cGMP在动  相似文献   

9.
通过静脉注射的方法研究了大肠杆菌仙毒素对山羊红细胞膜损伤的膜泵分子活性的变化及654-2(山莨菪碱)的保护效应。结果表明,ET处理组在1h,3h红细胞膜Na^+-K^+ATPase(腺苷三磷酸酶,简称ATP酶),Ca^2+,Mg^2+-ATPase活性均高于对照组,5h有下降趋势并一直持续到9h。  相似文献   

10.
通过4360只近交系小鼠体重分析,得出生长曲线:雄性r=25.2417/1+4.7803e^-0.40041x,相关系数R=0.9898,相关指数R^2=0.9797。雄性y=23.7645/1+3.9645e^-0.33397x,R=0.9825,R^2=0.9652。  相似文献   

11.
通过生长曲线非线性拟合模型可以预测家畜的生长发育速率以及生长曲线的变化情况。本研究运用Logistic、Gompertz和Von Bertalanffy模型分析拟合了高原型藏羊的早期生长发育曲线。结果表明:3种模型均能较好地拟合高原型藏羔羊的生长曲线(R2>0.99),其中,以Von Bertalanffy模型拟合效果最佳。在Von Bertalanffy模型中,公羔拐点月龄、拐点体重和最大日增重分别为1.35、12 kg和246.67 g·d?1,母羔拐点月龄、拐点体重和最大日增重分别为1.36、11.96 kg和239.33 g·d?1。根据此模型建立的高原型藏羊早期发育阶段的生长曲线,可为早期选育提供理论依据。  相似文献   

12.
使用Logistic模型配合家畜生长曲线时,应以家畜成年体重为模型中的最大生长量估计值,其他参数以实测值直接估计。采用四个实例比较了这种配合模型的方法与经典教科书上介绍的方法,表明这种新方法较优。  相似文献   

13.
Mastitis in cows can be defined as a binary trait, reflecting presence or absence of clinical mastitis (CM), or as a count variable, number of mastitis cases (NCM), within a defined time interval. Many different models have been proposed for genetic analyses of mastitis, and the objective of this study was to evaluate the predictive ability and sire predictions of a set of models for genetic evaluation of CM or NCM. Linear- and threshold liability models for CM, and linear, censored ordinal threshold, and zero-inflated Poisson (ZIP) models for NCM were compared in a cross-validation study. To assess the ability of these models to predict future data, records from 620492 first-lactation Norwegian Red cows, which were daughters of 3064 sires, were evaluated in a fourfold cross-validation scheme. The mean squared error of prediction was used for model comparison. All models but ordinal threshold model equally performed when comparing the overall predictive ability. This result was on average, across sick and healthy cows; however, the models behaved differently for each category of animals. For example, healthy cows were predicted better by the threshold and linear models for binary data and ZIP model, whereas for mastitic cows, the ordinal threshold model was by far the best model. Predicted sire effects and rankings of sires were highly correlated across all models. For practical purposes, the linear models are very competitive with the nonlinear models.  相似文献   

14.
数学模型在畜禽氨基酸需要量研究上的应用   总被引:1,自引:1,他引:1  
本文主要论述了线性模型、指数模型及折线模型在畜禽氨基酸需要量研究上的应用。  相似文献   

15.
河北柴鸡1~16周龄生长曲线分析与拟合的比较研究   总被引:18,自引:2,他引:18  
对河北柴鸡1-16周龄生长曲线进行了分析和非线性曲线拟合研究。结果表明,Logistic模型、Gompertz模型和Von Bertalanffy模型都能很好地拟合河北柴鸡的生长曲线(R^2分别为0.99598、0.99837和0.99809),但Gompertz模型在拟合度和预测体重效果方面相对较好。  相似文献   

16.
Different models are available to estimate species’ niche and distribution. Mechanistic and correlative models have different underlying conceptual bases, thus generating different estimates of a species’ niche and geographic extent. Hybrid models, which combining correlative and mechanistic approaches, are considered a promising strategy; however, no synthesis in the literature assessed their applicability for terrestrial vertebrates to allow best-choice model considering their strengths and trade-offs. Here, we provide a systematic review of studies that compared or integrated correlative and mechanistic models to estimate species’ niche for terrestrial vertebrates under climate change. Our goal was to understand their conceptual, methodological, and performance differences, and the applicability of each approach. The studies we reviewed directly compared mechanistic and correlative predictions in terms of accuracy or estimated suitable area, however, without any quantitative analysis to support comparisons. Contrastingly, many studies suggest that instead of comparing approaches, mechanistic and correlative methods should be integrated (hybrid models). However, we stress that the best approach is highly context-dependent. Indeed, the quality and effectiveness of the prediction depends on the study's objective, methodological design, and which type of species’ niche and geographic distribution estimated are more appropriate to answer the study's issue.  相似文献   

17.
为研究儋州鸡生长发育规律和各阶段的生长速度,本试验采用Gompertz、Logistic和Bertalanffy 3种非线性模型对黑色羽系和麻花色羽系儋州鸡0~18周龄体重生长数据进行拟合和分析,选取黑色羽系、麻花色羽系儋州鸡各200只(公、母各半),分别于0、2、4、6、8、10、12、14、16和18周龄晨饲前空腹称重并记录,并利用3种非线性模型对儋州鸡生长曲线进行拟合比较分析。结果显示,2种羽色儋州鸡实测生长曲线基本一致,接近于"S"型,符合正常生长发育规律,2种不同羽色儋州鸡母鸡0~18周龄的体重实测值差异不显著(P>0.05),公鸡0~16周龄的体重实测值差异不显著(P>0.05),而16~18周龄麻花色羽系公鸡体重显著高于黑色羽系公鸡(P<0.05)。3种非曲线模型拟合度(R2)均在0.992以上,均能较好地拟合2个羽系儋州鸡的生长曲线,且模型的预测曲线与实际观测曲线基本吻合,但Gompertz模型曲线吻合度高于Logistic和Bertalanffy模型曲线,且母鸡比公鸡拟合效果好。本研究结果初步揭示了儋州鸡的生长发育规律和各阶段的生长特征,可为儋州鸡选育、生产和产业化发展提供科学依据。  相似文献   

18.
不同能量水平对朗德鹅生长曲线的影响研究   总被引:2,自引:0,他引:2  
在不同能量水平下,运用Logistic模型和Gompertz模型对朗德鹅0~10周龄生长曲线进行了分析和非线性曲线拟合研究。结果表明,不同生长阶段,朗德鹅公鹅、母鹅的适宜能量水平不同,Logistic模型和Gompertz模型都能很好地拟合朗德鹅的生长曲线,但Gompertz模型在拟合度和预测体重效果方面相对较好。中等能量水平下,2周龄前公鹅、母鹅的生长曲线基本一致,之后公鹅则明显高于母鹅,且保持较长时间的快速生长状态,公鹅的拐点体重显著高于母鹅,但拐点日龄的出现却晚于母鹅。  相似文献   

19.
运用动物模型BLUP法时敖汉细毛羊的早期性状和产毛性状进行分析得出:模型(1)适合估计周岁重、断乳毛长度和断乳毛细度;模型(4)适合估计初生重和断乳重;模型(5)适合估计产毛量、体重和毛长度;模型(7)适合估计毛细度、毛弯曲分、毛密度分和毛油汗分.  相似文献   

20.
奶牛泌乳曲线数学模型拟合和早期预报   总被引:11,自引:2,他引:9  
本研究根据北京地区黑白花奶牛500个完整泌乳期的产奶记录资料研究了Wood模型、改进多项式模型、回归模型的拟合以及回归模型的预报情况。拟合结果表明,利用Wood模型来估计北京地区黑白花奶牛产奶量是可行的,但在取样间隔天数较大时估计奶量与实际奶量间有较大的偏差。鉴于此,作者提出了改进多项式模型,采用了ALI的回归模型,按对Wood模型进行拟合的同样方法对这两个模型进行了拟合,拟合精确度都较Wood模型有所改进。取样间隔天数大时,改进多项式模型的拟合精确度提高的幅度较大。回归模型的预报奶量与实际奶量呈较一致的变化规律,这对早期选种具有一定的实践意义。  相似文献   

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