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131.
BACKGROUND: Retired racing Greyhounds are becoming common as pets. Because of their unique physiology, results of routine laboratory tests are frequently outside the reference interval for dogs. Compared with other breeds, Greyhounds have low serum protein concentrations, but the concentrations of different serum protein fractions have not been reported. OBJECTIVES: Our objectives were to evaluate the results of serum protein electrophoresis (SPE) in healthy, retired racing Greyhounds and compare them with a control group of age- and gender-matched non-Greyhound dogs. METHODS: Agarose gel electrophoresis was done using a standard method; the gels were stained with amido black and scanned with a Cliniscan 2 densitometer (Helena Laboratories, Beaumont, TX, USA). Protein fractions were identified by visual inspection of the electrophoretogram. A Student's t-test assuming equal variances was used to compare the concentration of the different fractions between groups. RESULTS: The concentrations of total protein, total globulins, and alpha-1-, alpha-2-, beta-1-, and beta-2-globulins were significantly lower and the albumin to globulin (A:G) ratio was significantly higher in Greyhounds than in non-Greyhound dogs (P < .05). There was no significant difference in albumin or gamma-globulin concentrations. CONCLUSIONS: Low serum protein concentrations in Greyhounds are the result of low concentrations of a- and b-globulins. These results should be kept in mind when evaluating both healthy and sick Greyhounds. Additional studies are needed to identify the individual proteins associated with low alpha- and beta-globulin concentrations in Greyhounds.  相似文献   
132.
刘飞  喻夜兰  邹冬生  朱育峰  黄月飞 《草业科学》2016,33(11):2259-2265
主要采用扫描电子显微镜技术,对收集的20个龙须草(Eulaliopsis binata)种质资源叶片进行电镜扫描,结果表明,不同种质资源叶片形态中的叶长、叶宽、叶面积,以及叶解剖结构中的叶片表皮厚度、叶片厚度、叶片气孔密度、叶片气孔长、叶片气孔宽、叶片纤维细胞直径、胞壁厚度、腔径、腔壁比等均呈现出显著或极显著差异,以优选造纸材料中重要指标壁腔比进行聚类分析,可将供试龙须草种质资源造纸性能分为最优、较好、较差和最差4类。试验结果可为中国南方丘陵区龙须草种质资源良种选育和开发利用研究提供依据。  相似文献   
133.
试验以21周龄新扬州种公鸡为对象,研究了不同粗蛋白水平日粮对种公鸡繁殖性能的影响。结果表明,粗蛋白质水平为14%的B组公鸡精液量、精子活力和精子密度均明显地高于粗蛋白水平为11%的A组和粗蛋白质水平为17%的C组,而精子畸形率为B组最低(P>0.05);日粮粗蛋白水平对成年种公鸡的睾丸性状影响不大(P>0.05),而年龄对公鸡的睾丸性状有着显著的差异(P<0.05);A组的血浆中睾酮T、促黄体素LH和促卵泡素FSH含量分别比B组高了6.34%、19.64%和3.88%,比C组高了7.20%、17.54%和9.84%,差异不显著(P>0.05)。  相似文献   
134.
Oocyte maturation in mammals is characterized by a dramatic reorganization of the endoplasmic reticulum (ER). In mice, the ER forms accumulations in the germinal vesicle (GV) stage and distinctive cortical clusters in metaphase II (MII) of the oocyte. Multiple evidence suggests that this ER distribution is important in preparing the oocyte for Ca2+ oscillations, which trigger oocyte activation at fertilization. In this study, we investigated the time course and illustrated the possible functional role of ER distribution during maturation of porcine oocytes by immunostaining with protein disulfide isomerase (PDI). PDI forms clusters in the cytoplasm of oocytes. After immunostaining, PDI clusters were identified throughout the cytoplasm from the GV to metaphase I (MI) stage; however, at the MII stage, the PDI formed large clusters (1–2 µm) in the animal pole around the first polar body. PDI distribution was prevented by bacitracin, a PDI inhibitor. Our experiments indicated that, during porcine oocyte maturation, PDI undergoes a dramatic reorganization. This characteristic distribution is different from that in the mouse oocyte. Moreover, our study suggested that formation of PDI clusters in the animal pole is a specific characteristic of matured porcine oocytes.  相似文献   
135.
Avian leukosis virus subgroup A (ALV‐A) is a retrovirus which infects egg‐type chickens and is the main pathogen of lymphoid leukosis (LL) and myeloid leukosis (ML). In order to greatly enhance the diagnosis and treatment of clinical avian leukemia, two monoclonal antibodies (MAbs) to ALV‐A were developed by fusion between SP2/0 and spleen cells from mice immunized with expressed ALV‐A env‐gp85 protein. Using immunofluorescence assay (IFA), two MAbs reacted with ALV‐A, but not with subgroups B and J of ALV. Western blot tests showed that molecular weight of ALV‐A envelope glycoprotein recognized by MAbs was about 53 kD. Isotyping test revealed that two MAbs (A5C1 and A4C8) were IgG1 isotypes. These MAbs can be used for diagnosis and epidemiology of ALV‐A.  相似文献   
136.
A grazing trial was conducted at the Kokstad Agricultural Station to compare the dry matter digestibility (DMD) and crude protein content (CP) of diets selected by four fistulated cattle which were continuously and rotationally grazing sourveld. Two stocking rates of 1,0 and 2,3 animals/ha (0,5 and 1,2 LSU/ha) were applied under each grazing method. The mean DMD and CP values of diets selected in the continuous and rotational grazing treatments, respectively, were: DMD=64,3%, 62,3%; CP=6,63%, 6,88%. The effect of stocking rate on the quality of the diet selected varied between the two grazing methods. DMD and CP of diets selected under rotational grazing decreased with time during the week‐long period of stay in each paddock. On average, DMD and CP values on the first and sixth day respectively, were: DMD=66,6%, 60,5%; CP=8,37%, 6,01%. These differences were more pronounced at the higher than at the lower stocking rate. It was concluded that, although some of the treatment differences were small, grazing method differences in the DMD of diets might at least partially account for observed differences in livemass gains under the two grazing systems.  相似文献   
137.
The quality of diet selected by steers fistulated at the oesophagous was related to veld condition in a simulated rotational grazing system on the Natal Sour Sandveld. Six camps, ranging in veld condition score from 8,5 to 53%, were grazed simultaneously for a two‐week period in spring, summer, autumn and winter. Fistula samples were collected on the first, middle and last day of a period of occupation in a camp. Samples were analysed in terms of crude protein (CP), in vitro digestibility (IVD) and plant‐part (% leaf, % stem and % dead material) composition. Dietary quality in terms of CP, IVD and plant‐part composition was not related to veld condition but was dependent largely (P≤0,01) upon season and to a lesser extent upon period of occupation in a camp. It was concluded that in sourveld areas, where dietary quality may be limiting, the veld condition score may be a poor index of potential animal production.  相似文献   
138.
营养水平对仔猪断奶综合征的影响   总被引:2,自引:0,他引:2  
试验选取杜×长×大三元杂交仔猪,随机分为2个处理组,每个处理3个重复,每个重复10头仔猪.试验组饲喂5008配合日粮.对照组饲喂5000配合日粮.针对仔猪断奶综合征的表现特征,分别测定各组猪生长性能和腹泻率等指标.试验结果表明,饲粮中合有高水平的蛋白质及能量对断奶仔猪有促生长作用,可缓解仔猪断奶综合征的发生.  相似文献   
139.
表达新城疫病毒F基因重组鸡痘病毒的筛选   总被引:1,自引:0,他引:1  
将转移载体P11SF和PN11SF分别与282E4株鸡痘病毒(282E4 strain fowlpox virus,282E4FPV)和大空斑株鸡疽病毒(large plaque strain fowlpox virus,LP FPV)共转染鸡胚成纤维细胞,通过蓝斑筛选,得到4株重组鸡痘病毒rFPV282E4-SFA、rFPVLP,-SFA、rFPV282E4-SFB和rFPVLP-SFB,通过PCR和间接免疫荧光鉴定均为阳性,另外将各重组病毒分别传20代,测其遗传稳定性,结果显示均具有良好的稳定性。对SPF鸡进行免疫效力试验,攻毒后均100%保护,而对于商品鸡,保护率分别为64%、60%、52%和88%。  相似文献   
140.
本试验选用五龙鹅蛋用系与快长系各150只进行网床育肥试验,测定血浆总蛋白质含量,并进行PAGE电泳。结果显示:初生雏鹅血浆总蛋白质含量较高,随着日龄(1~90 d)增加呈先下降后升高趋势,以对数函数和抛物线函数分段拟合效果较佳,R2为0.9445、0.9568;血浆总蛋白质含量在性别间差异不显著,品系间差异显著。PAGE电泳结果表明:血浆中蛋白质种类在品系、性别间没有差异,随日龄的增加亦没有条带变化。清蛋白含量的变化是引起血浆总蛋白质含量变化的主要因素。  相似文献   
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