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1.
为了探讨青年母水牛尿中嘌呤衍生物排出量的变化规律,试验选取3头24月龄左右、体重相近的青年瘘管母水牛,采用随机区组试验设计.分别饲喂3种不同采食水平的试验日粮.结果表明:随着采食水平的降低,营养物质的表观消化率呈递增趋势(P<0.05);粪氮(P<0.01)、尿氮(P<0.05)呈递减趋势;尿中嘌呤衍生物的排出量显著降低(P<0.05),且与微生物氮估测值之间有显著的回归关系:Y=3.542 7X-25.285 0(R2=0.990 7;n=3),Y=6.209 3X+7.567 9(R2=0.990 7;n=3;P<0.05),与可消化有机物干物质采食量之间也有存在显著的线性相关:Y=6.209 3X+7.567 9(R2=0.996 1;n=3;P<0.05);肌酸酐的排出量稳定在40 mmol/d左右,各处理间无显著差异(P>0.05).  相似文献   

2.
成纤维生长因子4(FGF4)是在哺乳动物胚胎发育过程中第一个被发现的FGF分子,在促进滋养层细胞的增殖方面具有广泛的作用。已经证实,FGF4是小鼠早期胚胎发育过程中的一个重要因子,异常表达会影响早期胚胎的发育,并影响小鼠胎盘的发育及功能。截至目前,有关FGF4在牛胎盘发育过程中的表达尚无报道。本试验运用石蜡切片HE、PAS、免疫荧光染色技术和实时荧光定量PCR(qRT-PCR)技术对妊娠早期牛胎盘组织结构特征及胎盘组织中FGF4的细胞定位和mRNA表达规律进行研究。结果显示,在所检测的各胎龄胎盘的羊膜、子叶及肉阜组织均检测到Fgf4 mRNA,各部位表达量依区域和孕龄而异;在牛胎盘块的单核滋养层细胞、滋养层巨细胞、肉阜上皮、子宫内膜上皮及子宫腺等部位的细胞质均观察到FGF4阳性反应,滋养层巨细胞及子宫腺上皮呈强染色。可见,在妊娠早期的牛胎盘组织存在FGF4及其mRNA,随着胎龄的增加其表达量在胎儿胎盘(子叶)表现为先降低而后增高的规律,而在母体胎盘(肉阜组织)则呈现先逐渐升高然后降低的趋势。  相似文献   

3.
饵料中蛋白质、糖类、脂类对点带石斑鱼生长的影响   总被引：2，自引：1，他引：1  
采用均匀设计U5(53)法研究了饵料中蛋白质(X1)、糖类(X2)、脂类(X3)对点带石斑鱼生长的影响。试验进行了56d。对增重率(Y1)、特定生长率(Y2)、饵料系数(Y3)做线性回归分析,得出增重率的回归方程为:Y1=-128.392+26.4063X3+0.0252005X12-1.11842X3(2R2=0.9672),特定生长率的回归方程为:Y2=-1.13695+0.280137X3+0.000250155X12-0.011822X3(2R2=0.9617),饵料系数的回归方程为:Y3=3.42262-0.0335425X2-0.0557297X3-0.00046018X12(R2=0.9860)。Y1max=106.502时,X1=56、X3=11.805;Y2max=1.307时,X1=56、X3=11.848;Y3min=0.73时,X1=56、X2=14、X3=14。糖类在Y1、Y2两个回归模型中被剔除。在糖类含量固定为6.00%的情况下,根据特定生长率的等值线图得出生产中饵料中蛋白质、脂类最适含量分别为48.30%和11.85%。  相似文献   

4.
三聚氰胺在鸭蛋中的沉积和消除规律的研究   总被引：2，自引：1，他引：1  
本试验旨在研究日粮中添加不同水平的三聚氰胺(melamine,MEL)在鸭蛋中的沉积和消除规律.选用体重为(1.66±0.16)kg和产蛋率为(75.15±3.29)%的19周龄健康金定产蛋鸭756只,随机分成7个处理,每个处理设6个重复,每个重复18只.7种试验日粮的MEL添加水平分别为:0、1、2、5、25、50和100 mg/kg.各处理分别连续饲喂含不同水平MEL的日粮21 d(沉积试验),随后改喂基础日粮21 d(消除试验),试验期共42 d.于沉积和消除试验的第1～11天、第13天、第15天、第17天和第21天分别测定鸭蛋可食部分中的MEL和三聚氰酸(cy-anuric acid,CYA)含量.结果表明,0～5 mg/kg的4个处理之间鸭蛋中MEL含量差异不显著(P>0.05),25～100 mg/kg的3个处理之间差异极显著(P<0.01),且均极显著高于0～5 mg/kg的4个处理(P<0.01);鸭蛋MEL含量(Y,mg/kg)与日粮MEL添加水平(X,mg/kg)的关系方程为:y=0.0121X+0.0165(R2=0.9994),MEL由日粮到鸭蛋中的生物富集系数为0.0121;通过鸭蛋排出的MEL(Y,mg/d)与蛋鸭摄人的MEL(X,mg/d)拟合的曲线为:Y=0.2618X+0.0947(R2=0.9999),MEL由蛋鸭到鸭蛋的母体转移系数为0.2618.日粮MEL添加水平越高,鸭蛋中的消除半衰期越短,完全消除需要的时间越长;5、25、50和100 mg/kg处理鸭蛋中的MEL含量(Y,mg/kg)随时间(X,d)消除方程分别为:Y=0.0802X-0.747(R2=0.7775)、Y=0.3268X-1.1608(R2=0.9871)、Y=0.5912X-1.3403(R2=0.9922)和Y=1.2004X-1.3956(R2=0.9883),根据上述方程计算各处理鸭蛋中MEL完全消除时间分别为3.48、7.81、9.31和14.61 d;鸭蛋中未检测到CYA.结果显示,MEL在产蛋鸭日粮中浓度越高,其鸭蛋中沉积最越大,消除时间越长.  相似文献   

5.
牛卵巢内卵泡及卵母细胞生长发育的组织学研究   总被引：3，自引：0，他引：3  
随机摘取牛离体卵巢18枚,常规石蜡切片,光镜下共观察卵泡5 818个,并测得卵泡、卵母细胞直径和透明带厚度（平均值）。结果:在整个卵泡发育过程中,卵泡与卵母细胞发育是完全显著正相关（P<0.01,R=0.9906）,其中腔前期P<0.01,R=0.9917,有腔期P<0.01,R=0.9951。腔前卵泡时期,卵泡和其卵母细胞直径增长幅度大体相等,而从有腔卵泡始,卵泡生长速度远远大于其卵母细胞。透明带与卵母细胞发育呈不显著正相关（P>0.05,R=0.9521）。  相似文献   

6.
优质肉鸡矮小型母系品系(S2系)产蛋性状的通径分析   总被引：2，自引：0，他引：2  
以4429只优质肉鸡矮小型母系品系(S2系)核心群个体产蛋数据为试验材料,运用通径分析法研究开产日龄(x1)、开产体重(x2)、开产蛋重(X3)、24周产蛋数(X4)、28周产蛋数(X5)5个产蛋性状因子与43周产蛋总数的关系.结果表明:各性状因子的通径系数分别为-0.17576、0.051788、-0.02997、0.259459、0.597501;28周产蛋数是影响43周产蛋数的主要决定因子.各性状(X1)对43产蛋数(Y)的最优回归方程为:Y=56.826-0.292X1+0.006X2-0.030X3+0.770X4>+3.106X5(P<0.01),总相关系数为0.8760,决定系数为0.7674.  相似文献   

7.
本文旨在通过测定常用植物性饲料中总磷、植酸磷和天然植酸酶的含量,并结合动物试验的结果,探讨建立猪植物性饲料可消化磷预测模型的可行性,为磷资源的有效合理利用、降低养殖业排泄物对环境的磷污染提供简便方法。选用19种植物性饲料原料和2种配合饲料,在分析测定其总磷、植酸磷和天然植酸酶酶活的基础上,以25 kg左右三元杂交生长瘦肉型猪为试验动物,采用6×6(2个)、4×4(3个)拉丁方设计,以玉米淀粉-豆粕为基础日粮,分别按替代法和回归法,测得了单一饲料原料中磷的表观消化率和真消化率,并建立了可消化磷的预测模型。所建立的预测模型分别为:表观可消化磷(g/kg)Y=-0.411 0.405X1-0.227X2 0.003 15X3(R2=0.822,RSD=0.272,P<0.001),其中X1=总磷(g/kg),X2=植酸磷(g/kg),X3=植酸酶活(FTU/kg),下同;真可消化磷(g/kg)二元模型Y=0.062 9 0.655X1-0.412X2(R2=0.859,RSD=0.386,P<0.001),三元模型Y=-0.220 0.589X1-0.304X2 0.003X3(R2=0.882,RSD=0.244,P<0.001)。可以用饲料总磷、植酸磷和天然植酸酶酶活指标来预测植物性饲料可消化磷的含量,比较而言,对真可消化磷预测结果的准确性更高。  相似文献   

8.
对51条青海湖裸鲤体重、体尺性状剖分测定及应用SAS(6.12版)系统软件进行相关回归分析,结果表明:Y1(体重)与X1(头重)、X2(鳍重)、X3(躯尾重)、X4(肠容物重)相关系数极显著,其最优回归方程式:总方程:Y1=-2.24390+0.99898X3+1.30604X4(R2=0.9210p0.0001),♀:Y1=1.93002+0.88362X3+1.24584X4(R2=0.9198P0.0001),♂:Y1=8.97641+1.20310X3(R2=0.9956p0.0001)。Y2(体长)与X5(头长)、X6(躯干长)、X7(尾长)相关系数极显著,其最优回归方程式:♀:Y2=3.62909+2.25776X5+1.10367X7(R2=0.8150p0.0032),♂:Y2=0.97145+0.95331X6(R2=0.9534p0.0077)。  相似文献   

9.
《畜牧与兽医》2015,(8):39-42
利用SPSS 11.5软件中的11种曲线回归模型对小尾寒羊羔羊体重和体尺进行曲线拟合,根据相关指数R2和T检验选择建立最优回归方程,并对曲线模型估计值与测量值进行了比较。生长发育最优回归方程如下,体高:Y=41.058 6+5.368 6X-0.370 7X2;体长:Y=46.263 3+13.116 1ln X;胸围:Y=48.779 5X0.261 6;胸宽:Y=14.036 7X0.231 2大腿围:Y=27.234 2X0.169 6;腰角宽:Y=5.678 6+6.375 5X-1.329 9X2+0.097 5X3管围:Y=e(2.149 1-0.407 8/X);体重:Y=9.062 8X0.733 0,上述拟合曲线方程均可靠(R2都在0.917 1~0.994 0之间),可以用来预测小尾寒羊早期生长发育体重及体尺。  相似文献   

10.
对成年斑嘴鸭胫长(X1)、胫围(X2)、胸宽(X3)、胸深(X4)、胸围(X5)、体斜长(X6)、龙骨长(X7)、体重(Y)8个性状进行相关分析、通径分析,并建立体重回归方程。结果表明,斑嘴鸭胸宽、胸深、胸围、体斜长、龙骨长与体重之间存在极显著的相关性(P<0.01),在各指标之间,也存在者复杂的相关性。胸深、胸围对体重的影响主要以直接作用为主,而胫围、体斜长和龙骨对体重的影响以间接作用为主。各指标对体重的决定系数大小排序为:R25>R24>R27>R23>R26>R21>R22。建立斑嘴鸭成年体重最优回归方程为:Y=-814.633+42.132X5+91.450X4-85.571X2(R2=0.717)。  相似文献   

11.
Objective   To determine bovine fetal characteristics significantly associated with increasing gestational age as measured via transcutaneous ultrasonography over the right flank.
Methods   The length of gestation at date of pregnancy diagnosis via transcutaneous and transrectal ultrasonography was determined for 224 dairy cattle by estimation from subsequent calving dates. A separate dataset was created for each measurable fetal characteristic (i.e. thoracic diameter, abdominal diameter, umbilical diameter, placentome length and placentome height) and risk factors significantly associated with gestational age at pregnancy diagnosis within each dataset, including the fetal characteristic, were identified.
Results   Abdominal diameter was the most frequently observed fetal characteristic and thoracic diameter was the least. Gestational age at pregnancy diagnosis (d) was significantly associated with fetal thoracic diameter (P < 0.01), abdominal diameter (P < 0.01) and umbilical diameter (P = 0.02) when measured via transcutaneous ultrasound. Within each model, sire breed, dam breed, dam age and/or calf sex were also significantly associated with gestational age. Gestational age at pregnancy diagnosis was not significantly associated with either placentome height or length (P > 0.05).
Conclusion   Fetal thoracic diameter, abdominal diameter and umbilical diameter were found to be significantly associated with gestational age between approximate days 73 to 190 of gestation. Transcutaneous ultrasonography may prove a useful method of estimating gestational age in the absence of accurate breeding records.  相似文献   

12.
One hundred and sixty-two 18-month-old farmed red deer were used to test the accuracy of pregnancy detection and equations for predicting gestational age. Deer ranging from 30 to 110 days gestation were examined by rectal ultrasonography using a 5 MHz transducer while they were standing. Each scan was recorded on video tape for measurements of uterine diameter, amniotic sac diameters, crown-rump length, head length, head diameter, nose length, chest depth, chest width and placentome base-apex length and width. Fetal age was calculated from the mean of the age predictions derived from each dimension measured on individual deer, for 132 deer between 44 and 110 days gestation. All the hinds diagnosed as pregnant produced offspring, and all the hinds diagnosed as not pregnant failed to produce offspring. Between one and six fetal and uterine dimensions were measurable and the number measurable increased with fetal age. The mean error of calving date prediction in 132 deer was 0.97 days. The error of prediction when measurements were made between 44 and 60 days was 0.44 days, whereas between 61 and 80 days and between 81 and 110 days the errors were +0.95 and +4.72 days, respectively. The estimates of calving date were all within 13 days of the calving date.  相似文献   

13.
Twenty-nine farmed red deer hinds two years of age or older were observed during mating in April, and the dates of oestrus and, or, mating were recorded. From May 28 to August 13, at approximately weekly intervals, the deer's uteri and associated structures were examined by rectal ultrasound using a 5 MHz transducer while the deer were held standing in a restraining device. The uterine diameter, amniotic sac diameters, crown-rump length, head length, nose length, chest depth, chest width and placentome base-apex and width were measured for each scan. Quadratic regression equations were computed for each measurement with age, using data from hinds with known mating dates, and the chronological sequence of appearance of a range of uterine and fetal characteristics was recorded. There were significant quadratic regressions. (P less than 0.001) for each of the measurements. The accuracy of pregnancy detection to 117 days after conception was 99.3 per cent and to 132 days after conception 97.4 per cent. The confirmation of non-pregnancy was 96.5 per cent accurate. The regressions of each measurement by age should provide an accurate method for the estimation of fetal age in red deer.  相似文献   

14.
In order to determine the variability inherent in conceptus-related measurements in first trimester bovine pregnancies, conceptus and fetometric parameters from beef cattle pregnancies (n=103) estimated to be between Days 36 and 103 of gestation were examined. During this period, the protein concentration of amniotic fluid ranged between 0.181 and 0.501mg/mL. The amniotic fluid volume gradually increased from <1mL at Day 36 to 950mL at Day 103 (R(2)=0.9275) and amniotic compartment dimensions (length, R(2)=0.9713; width, R(2)=0.9802) increased predictably with fetal growth. Conversely, allantoic fluid protein concentration and volume correlated weakly with fetal age. A significant linear correlation existed between fetal crown rump length (CRL) and crown nose length (R(2)=0.9899) confirming that either measurement can be employed in the ultrasonographic estimation of fetal age. The amniotic compartment and fetometric data presented here have both research and clinical value, particularly in relation to fetal development evaluation and pregnancy viability diagnosis.  相似文献   

15.
The interrelationships among d-11 conceptus size, d-105 placental weight, placental efficiency (the ability of the placenta to support fetal growth and development), fetal erythropoiesis, and uterine capacity were examined in 1/2 Meishan, 1/2 White crossbred gilts that were unilaterally ovariohysterectomized at 90 to 100 d of age. In Exp. 1, gilts were mated after at least one normal estrous cycle and then slaughtered at 105 d of gestation and number of fetuses and CL, placental weights, fetal weights, hematocrits, fetal plasma iron, and fetal plasma folate were measured. In Exp. 2, gilts were mated and plasma progesterone was measured on d 2 and 3 of gestation. On d 11, the length of the remaining uterine horn was recorded and the uterine horn was flushed with minimal essential medium. Number of CL, conceptus number, conceptus diameters, and total uterine flush retinol-binding protein (tRBP), acid phosphatase (tAP), and folate-binding protein (tFBP) were measured. Gilts were mated again and slaughtered at 105 d of pregnancy and the same traits measured in Group 1 were recorded. Plasma progesterone concentrations on d 2 and 3 were correlated with average conceptus diameter on d 11 (r = 0.60, P < 0.01, for each day). In contrast, tRBP (r = 0.49, P < 0.01), tAP (r = 0.53, P < 0.01), and tFBP (r = 0.51, P < 0.01) in uterine flushings on d 11 were only correlated with d-3 plasma progesterone concentrations. No correlations between d-11 average conceptus diameter or d-11 uterine length with d-105 uterine capacity were observed. Uterine capacity was negatively correlated with placental weight, fetal weight and fetal hematocrit (r = -0.36, P < 0.01; r = -0.44, P < 0.01; r = -0.32, P < 0.01; respectively). Hematocrits were correlated with fetal plasma iron (r = 0.50, P < 0.01) and folates (r = 0.44, P < 0.01). Hematocrit, plasma iron, and plasma folate were each correlated with residual fetal weights after adjusting for placental weight (a measure of placental efficiency), and accounted for 11% of the variation in this trait. These data suggest that conceptus diameter and uterine protein secretion on d 11 may be influenced by the onset of progesterone secretion by the CL, but do not support an influence of conceptus growth during early pregnancy on uterine capacity. These results also suggest that reducing placental and fetal weights will likely result in increased uterine capacity.  相似文献   

16.
The concentration of bovine placental lactogen (bPL) was determined in fetal placentomes, allantoic fluid, amniotic fluid, maternal and fetal plasma throughout pregnancy. In addition, chromatofocusing chromatography was used to separate the different forms of bPL found both in fetal serum and in placental homogenates in order to determine whether the different forms that have been reported to exist in the cotyledon are also found in the fetal circulation. Reproductive tracts were collected from cows between 109 and 247 days of pregnancy. The concentration of bPL in the fetal cotyledonary tissue was measured by both radioreceptor assay and radioimmunoassay, both assays showed that the concentration of bPL in the fetal portion of the placentomes remained constant throughout the period of pregnancy tested. The mass of the placenta increased approximately 10-fold during the period of study but the concentration of bPL in the maternal plasma was low (0.9±0.1 ng/ml) at all stages of pregnancy tested. The mean concentration of bPL (Mean ± S.E.M.) in amniotic and allantoic fluid was 0.4±0.1 and 1.2±0.2 ng/ml respectively. Fetal blood contained the highest concentrations of bPL, from 11.6 to 18.4 ng/ml, and the concentration tended to decrease with advancing gestation (slope = 0.07, P = 0.001). Several forms of bPL were found in the fetal circulation; however, a higher percentage of forms with more acidic isoelectric points were found in the fetal serum than in placental homogenates. These results suggest that either some forms of bPL are more stable or that the hormone isolated from placental tissue is not representative of the final secreted product.  相似文献   

17.
A study was undertaken to estimate gestational age, in terms of days from parturition, in medium and small size dogs by ultrasonographic examination. Serial ultrasonographic examinations were performed in four medium size pregnant bitches throughout two consecutive pregnancies and three small size pregnant bitches throughout one pregnancy, in order to determine the range of variation in the size of selected fetal structures throughout gestation. Formulae were derived to estimate the expected delivery date for both groups of bitches by measuring anatomical fetal structures, so that this method could be applied to a large number of different breeds. The determination of gestational age could be achieved with reasonable precision by selecting fetal structures. Prediction of parturition date was accurate to within one day by ultrasonographic measurement of the diameter of the gestational sac in early pregnancy and the biparietal diameter in late pregnancy in both small size breeds and medium size breeds.  相似文献   

18.
本文对酶花鹿血清羟脯氨酸、碱性磷酸酶活性年周期变化的研究结果表明：血清的羟脯氨酸含量和碱性磷酸酶活性变化,生茸期均极显著地高于非生茸期（Ｐ＜００１）。血清的羟脯氨酸含量（Ｘ）和碱性磷酸酶活性（Ｙ）在年周期变化上呈极显著正相关（Ｐ＜００１）,其回归方程为Ｙ＝５．３４Ｘ＋１３．２６（ｒ＝０．５５,ｎ＝２５）。  相似文献   

19.
妊娠早期绵羊子宫和胎儿实测与超声探查比较   总被引：2，自引：0，他引：2  
用Ｂ超跟踪探查的９头妊娠母羊，分别于妊娠５７、５８、５９、６０、８６、８７、８８、９６和１００ｄ剖检，实测其于叶直径、胎儿冠一臀长、头长和胎儿主要内脏。结果发现，直径最大的子叶在妊娠８６ｄ，说明以测子叶直径来预测胎龄，只适用于妊娠８６ｄ以前；妊娠５９ｄ观察到有胃液，妊娠８６、９６ｄ先后在直肠和结肠观察到有胎粪蓄积，９６和１００ｄ在羊水和胃内发现有小粪球，说明此时已有排粪和吞咽反射；妊娠８７和８８ｄ观察到膀胱有尿蓄积和睾丸降入阴囊。  相似文献   

20.
用5MHz线阵探头对14只母犬从配种后18d开始，每2d用B超探查1次；配种后36～48d，每3d探查1次；48d以后，于52、57d各探查1次。结果表明，于配种后18～22d确诊7只犬妊娠，7只空怀。有3只犬分剐在配种后24、36、39d发生流产。观察胎囊、胎儿、胎心、胎动、胎儿脏器、胎儿骨骼出现时间和测量胎囊大小、冠臀长、胎儿身长、头长、双顶径、胸深和心区大小，证明胎囊大小、胎儿冠臀长、身长、头长、双顶径、胸深与胎龄呈显著正相关。在配种后18～30d，观察子宫暗区大小可预测胎龄。在配种32d以后，观测胸深、双顶径或头长。可精确预测胎龄。  相似文献   

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