利用废弃沙坑驯化养鱼试验     

李云龙  樊金宏等 《黑龙江水产》2001,(3):14-15

随着城镇建设规模的扩大和高速公路的修建,需要大量的沙石、土方、而取完土方、沙石的场地大都是常年积水、沟壕交错、杂草从生,因无法复耕而被废弃,造成了巨大的土地资源浪费。据不完全统计,仅我县这样的废弃地就有100多处约4000多亩。有些人利用现有的自然条件养鱼,都因水凉、水位无法控制和捕捞困难而失败了。为了废物利用,发展养殖业,今年我们利用两处废沙坑建鱼池30亩,进行了养鱼试验,用科学合理的方法生产及管理,取得了良好的效果,探索出一条新的养鱼模式。  相似文献   

奶牛性别控制研究的新进展   总被引：1，自引：0，他引：1  

闻新棉  张俊功  李云龙 《山东畜牧兽医》2004,(3):37-38

动物性别的差异直接影响着人们对其利用的价值。对于奶牛养殖业，性别控制和早期胚胎的性别鉴定是人们长期以来期望应用到养殖业中的一个意义重大的课题。由于胚胎冷冻、胚胎分割及胚胎移植技术的发展，奶牛的性别控制显得越来越重要而且易于实现。  相似文献   

中国工业设计的发展     

张坤  乔浩轩  李云龙  连帅可 《山东饲料》2014,(2)

中国工业设计的发展有一步到位的直接,也有黑暗中摸索的缓慢。在工业设计这一概念引入中国的三十多年间,它有从不被重视到慢慢受到关注,期间经历了太多的困难。改革开放以来,中国成为了世界的工厂,我们走到哪里看到的是中国制造而不是中国创造。凤凰总会涅槃,中国的工业设计必将会走向世界。  相似文献   

鸽子毛滴虫病的防治     

李云龙 《中国畜禽种业》2012,8(7):131-131

鸽子的毛滴虫病是世界性分布的鸽原虫病。常发生于鸽上消化道,尤其是咽、喉部,导致口腔溃疡。本病发病率较高,对鸽的危害性极大,是鸽的常见病。1病原病原是鞭毛虫纲、毛滴虫科、毛滴虫属的禽毛滴虫,是原生动物的单细胞鞭毛虫。虫体呈梨形或长圆形,前端有4根前鞭毛,虫体外披一片沿虫体边缘向后伸延的波动膜和一根伸出虫体末端的轴刺。虫体凭借上述器官在体液中作螺旋式运动,以分裂方式增殖,约4小时便可增殖一世代。  相似文献   

植物免疫诱抗剂对黄瓜白粉病的防治试验     

王胤  李锦  张欣颖  李云龙  胡彬  孙海  郑建秋  曹金娟  王俊侠 《蔬菜》2021,(3):39-42

为明确植物免疫诱抗剂对黄瓜白粉病的田间防治效果,选择不同浓度5%氨基寡糖素水剂开展病害防治试验,并以0.5%几丁聚糖水剂为生物药剂对照,以42.4%唑醚·氟酰胺悬浮剂为化学药剂对照,以清水为空白对照。结果显示:5%氨基寡糖素水剂667 m²用量30 mL对黄瓜白粉病具有较好的防治效果,第1次施药后7 d防效达76.1%,推荐在病害发生初期间隔7 d连续施用2~3次。  相似文献   

Progression of Mycoplasma hyosynoviae infection in three pig herds. Development of tonsillar carrier state, arthritis and antibodies in serum and synovial fluid in pigs from birth to slaughter     

Hagedorn-Olsen T  Nielsen NC  Friis NF  Nielsen J 《Zentralblatt für Veterin?rmedizin. Reihe A》1999,46(9):555-564

In this investigation, natural infection with Mycoplasma hyosynoviae was followed in groups of individual pigs in three different herds with regard to occurrence of tonsillar carrier state, clinical arthritis and development of antibodies in serum and in synovial fluid. Antibodies were detected by a polyclonal enzyme-linked immunosorbent assay (ELISA) developed for experimental use. The infection with M. hyosynoviae progressed very differently in the three herds investigated. In one herd, the infection was apparently limited to adult pigs. In a second herd, all pigs became tonsillar carriers of M. hyosynoviae, but no mycoplasma-related arthritis nor any serological response was demonstrated within the growing-finishing period. In the third herd investigated, tonsillar infection was detected in all pigs, clinical cases of M. hyosynoviae arthritis followed and a moderate serological response was observed in some, but not all, pigs. In all three herds, M. hyosynoviae infection was carried in the tonsils of the adult pigs, but it was only occasionally transmitted from sows to piglets. Maternal antibodies were transferred to the piglets and persisted for approximately 8-12 weeks. After weaning, some pigs became infected before 20 weeks of age, while others did not. In the majority of cases, the tonsillar infection was established from 11 weeks of age or older. A latent tonsillar infection was present for a period of several weeks within the group of investigated pigs before cases of generalized infection and arthritis were seen. In some cases, generalization of M. hyosynoviae infection in the blood and in joints was observed in spite of the detection of an active serological response a few weeks earlier. The present work suggests that generalization of the infection and development of arthritis may depend on age, immunity, virulence factors and/or infection pressure; in some herds maybe combined with certain triggering mechanisms such as stress and lowered general resistance.  相似文献   

Mycoplasmas isolated from the respiratory tract of cattle and goats in Tanzania   总被引：3，自引：0，他引：3  

Kusiluka LJ  Ojeniyi B  Friis NF  Kazwala RR  Kokotovic B 《Acta veterinaria Scandinavica》2000,41(3):299-309

A microbiological study of the mycoplasma flora in the respiratory tracts of cattle and goats in selected regions of Tanzania is described. In the examination of cattle, mycoplasmas were isolated from 60 (17.8%) of the 338 examined lung samples, 8 (47.1%) of the 17 lymph nodes, 4 (13.3%) of the 30 pleural fluid samples and 4 (3.9%) of the 103 nasal swabs examined. All the isolates were identified as Mycoplasma mycoides subsp. mycoides, Small Colony type except for one isolate from pleural fluid which was identified as Mycoplasma arginini. M. mycoides subsp. mycoides, Small Colony type was isolated from samples originating from Dodoma, Iringa, Mbeya, Morogoro and Shinyanga regions where outbreaks of contagious bovine pleuropneumonia had been reported. In the examination of goats, mycoplasmas were isolated from 54 (34.0%) of the 159 examined lung samples, 41 (18.1%) of the 226 nasal swabs and 4 (40.0%) of the 10 pleural fluid samples. The species demonstrated were Mycoplasma capricolum subsp. capripneumoniae, M. mycoides subsp. mycoides, Small Colony type Mycoplasma ovipneumoniae and M. Capricolum subsp. arginini. The isolation of M. capripneumoniae in the Coast and Morogoro regions confirmed the presence of contagious caprine pleuropneumonia in the regions.  相似文献   

Increasing prevalence of Mycoplasma bovis in Danish cattle     

Kusiluka LJ  Ojeniyi B  Friis NF 《Acta veterinaria Scandinavica》2000,41(2):139-146

A study on the prevalence of mycoplasmas in pneumonic bovine lungs was performed on material submitted for diagnostic purposes at the Danish Veterinary Laboratory, Copenhagen. Among the 50 examined cases 43 (86.0%) were found to be infected with mycoplasmas. The predominant mycoplasmas were Ureaplasma spp. (72.0%), M. dispar (48.0%) and M. bovis (24.0%). Other mycoplasmas were M. bovirhinis (20.0%) and M. bovigenitalium (6.0%). Among the infected lungs multiple species infections were predominant (76.7%) over single species infections (23.3%) with M. dispar-Ureaplasma (25.6%), M. bovis-Ureaplasma (18.6%) and M. dispar-M. bovirhinis-Ureaplasma (11.6%) infections being the most frequently encountered combinations. There appears to be an increasing prevalence of M. bovis (24.0%) as compared to earlier reports (0.6-2.0%), thus calling for special attention upon this mycoplasma. Pulsed field gel electrophoresis (PFGE) analysis of 11 field isolates of M. bovis from 9 different farms revealed different profiles except for 2 isolates which were recovered from the same farm. Because mycoplasmas belonging to the 'M. mycoides cluster' were not encountered during this study; it appears that the Danish cattle population is still free from this group of mycoplasma in spite of their presence in some other European countries.  相似文献   

荧光定量PCR检测小鼠卵母细胞中Mad2 mRNA的表达     

王建英  杭苏琴  李云龙 《畜牧与兽医》2006,38(10):11-14

目的:应用SYBR G reen I染料法建立检测Mad2 mRNA表达的实时荧光定量PCR的方法,并探讨小鼠卵母细胞减数分裂成熟中Mad2 mRNA的表达。方法:采用实时荧光定量PCR的方法,以SYBR G reen I为荧光染料,梯度稀释的重组质粒为模板制作标准曲线,并以此方法分析了小鼠卵母细胞减数分裂成熟过程中Mad2 mRNA表达的动态变化。结果:建立了实时荧光定量检测方法分析小鼠卵母细胞中Mad2 mRNA的表达,该方法灵敏、特异,扩增效率接近100%。进行了标准曲线的制作,以及对目的基因Mad2转录水平的绝对定量。结论:实时荧光定量PCR是检测基因表达水平的理想选择,在小鼠卵母细胞减数分裂成熟过程中Mad2 mRNA表达存在动态变化。  相似文献   

庆城县光能资源对农作物生长的影响     

李云龙 《甘肃农业》2004,(8):57-57

庆城县光照日数多 ,太阳辐射量大 ,属北方长日照地区。光资源相对大于全国其它地区 ,对农作物的生长极为有利 ,但利用率低 ,距自然条件下的最大光能利用率相差很远。  相似文献