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51.
动物性食品中的药物残留量虽然很低,但对人体健康的潜在危害却甚为严重,对畜牧业生产影响巨大,而且影响深远,是国内外普遍关注的 相似文献
52.
H. Gao M.S. Lund Y. Zhang G. Su 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2013,130(5):333-340
Breeding animals can be accurately evaluated using appropriate genomic prediction models, based on marker data and phenotype information. In this study, direct genomic values (DGV) were estimated for 16 traits of Nordic Total Merit (NTM) Index in Nordic Red cattle population using three models and two different response variables. The three models were as follows: a linear mixed model (GBLUP), a Bayesian variable selection model similar to BayesA (BayesA*) and a Bayesian least absolute shrinkage and selection operator model (Bayesian Lasso). The response variables were deregressed proofs (DRP) and conventional estimated breeding values (EBV). The reliability of genomic predictions was measured on bulls in the validation data set as the squared correlation between DGV and DRP divided by the reliability of DRP. Using DRP as response variable, the reliabilities of DGV among the 16 traits ranged from 0.151 to 0.569 (average 0.317) for GBLUP, from 0.152 to 0.576 (average 0.318) for BayesA* and from 0.150 to 0.570 (average 0.320) for Bayesian Lasso. Using EBV as response variable, the reliabilities ranged from 0.159 to 0.580 (average 0.322) for GBLUP, from 0.157 to 0.578 (average 0.319) for BayesA* and from 0.159 to 0.582 (average 0.325) for Bayesian Lasso. In summary, Bayesian Lasso performed slightly better than the other two models, and EBV performed slightly better than DRP as response variable, with regard to prediction reliability of DGV. However, these differences were not statistically significant. Moreover, using EBV as response variable would result in problems with the scale of the resulting DGV and potential problem due to double counting. 相似文献
53.
Yan Li Ying Jia Kai Wen Hua Liu Mingchun Gao Bo Ma Wenlong Zhang Junwei Wang 《Veterinary immunology and immunopathology》2013,151(3-4):331-336
Bovine viral diarrhea virus (BVDV) is a member of the genus Pestivirus within the family Flaviviridae. NS3 is one of the immunodominance regions of the BVDV viral proteins. To identify the potential B-cell linear antigenic epitopes within BVDV NS3 region, serial overlapping truncations covering the whole region were expressed and purified, and screened by multistep of Western-blot. We found (1VCKKITEHERCHVNI15), (20AFFGVMPRGTTPRAPVR36), (46RRGLETGWAYTHQGGI61), (281EGDMATGITYASYGYFC297), (426YSGEDPANLRVVTSQSPYVVVATNAIESGV455) and (481FIVTGLKRMAVTVGEQA497) can be recognized by the BVDV infected bovine serum. These proteins have been confirmed by indirect enzyme-linked immunosorbent assay (I-ELISA). The results of this study might open new perspectives on the structure and antibody–antigen reaction of the non-structural proteins and may aid in the clinical application as well. 相似文献
54.
为了解过氧化物酶(POD)和酯酶(EST)同工酶在果蔗生长中的变化规律,本研究选择不同的取样时期和植株不同器官,对8个果蔗品种利用垂直平板聚丙烯酰胺电泳得出的叶片、根组织不同生育时期POD、EST同工酶酶谱进行聚类分析,并检测其相关性。结果表明:(1)不同品种间同工酶谱的遗传相似系数存在差异,特别是外引黑皮果蔗(Badila)与中国地方品种之间存在着一定的遗传差异;(2)不同生育时期叶片或根部的POD同工酶和EST同工酶酶谱的聚类图都存在着差异;(3)叶片中的POD、EST酶谱在各个生育时期均达到极显著相关。说明叶片是这两种酶基因表达的最重要活性部位,因此叶片可以作为同工酶分析较为稳定和适宜的采样部位。 相似文献
55.
Guangjun Guo Jianchang Gao Xiaoxuan Wang Yanmei Guo J.C. Snyder Yongchen Du 《Breeding Science》2013,63(3):239-245
An accurate and simple evaluation method is crucial for identifying whitefly resistance in tomato breeding. We developed an in vitro method for evaluating resistance of tomato leaves and tested this on wild and cultivated tomato varieties. We found that young leaves observed for whitefly oviposition after 8 hours provided appropriate comparative conditions. This method effectively distinguished resistance among tomato cultivars and wild species and also demonstrated significant difference in oviposition rates among leaf positions on susceptible cultivars. The in vitro test was as precise as in vivo test using intact plants and had advantages over in vivo test, and can be used for evaluating resistance in large populations. 相似文献
56.
猪繁殖与呼吸综合征病毒实验感染SPF猪外周血单核细胞和肺泡巨噬细胞早期凋亡细胞的观察 总被引:7,自引:0,他引:7
采用Annexin V-FITC/PI双染色法,用流式细胞仪检测了猪繁殖与呼吸综合征病毒(PRRSV)实验感染SPF猪不同时期外周血单核细胞和肺泡巨噬细胞感染Annexin V-FITC^+/PI^-细胞群(早期凋亡细胞群)。结果显示,PRRSV感染猪外周血单核细胞和肺泡巨噬细胞Annexin V-FITC^+/PI^-细胞群的表达率均明显高于正常对照猪,感染后24h表达率达最高值。 相似文献
57.
应用改良阻断ELISA检测禽网状内皮组织增殖病血清抗体 总被引:3,自引:0,他引:3
应用禽网状内皮组织增殖病病毒纯化抗原和抗REV单克隆抗体建立了改良阻断ELISA用于鸡血清中REV抗体检测,并对北京地区鸡群中随机采样的36份血清样本进行了检测,阳性率为5.6%。与间接ELSIA的检测结果进行了统计学比较,两种方法的阳性率无显著差异。结果表明本试验所建立的改良阻断ELISA可以用于鸡群REV感染的血清学调查。 相似文献
58.
今天,我们大家欢聚一堂,隆重举办中国饲料工业协会第五届大型企业联谊会暨2009饲料行业发展高层论坛,这是饲料行业的一大盛事.我谨代表农业部对会议的成功举办表示热烈的祝贺!近几年来,畜牧业发展很不平凡,难题多、任务重、压力大. 相似文献
59.
60.
Qi SS Wang WH Gao Q Xu XH He WH Zhaxi YP Tai LF 《Tropical animal health and production》2011,43(6):1219-1223
The distribution, size, and appearance of Peyer's patches vary according to species. In order to determine the anatomical
characteristics of Peyer's patches in small intestine of Bactrian camel, and age-related changes in the number of Peyer's
patches, 40 Bactrian camels of the following four age groups were studied: young (0.5–2 years), pubertal (3–5 years), middle-aged
(6–16 years), and old (17–20 years). The exact number of Peyer's patches was recorded, and the appearance of Peyer's patches
was described in detail. The results indicated that Peyer's patches of Bactrian camels not only have a particular anatomical
location and distinct appearance but also change with age. They were distributed in the whole small intestine and there were
four distinct types of Peyer's patches: nodular, faviform, cup-shaped, and cystic form Peyer's patches. However, the nodular
and cystic form Peyer’s patches are specific to Bactrian camel, which have not been found in other animals including Dromedary
camel. In addition, the distribution density of Peyer's patches in ileum was the maximum, then was jejunum and duodenum. Further
statistical analysis showed that the number of Peyer's patches was altered with age. The number peaked in 5-year-old camels
and declined subsequently with age. However, there was little change in the size of Peyer's patches in different age groups;
no age-related macroscopic variations in the shape or size of the Peyer's patches were found. Results obtained from this study
provide the basic information to further study on the gastrointestinal mucosal immunity of Bactrian camel. 相似文献