Survey of mycotic mastitis in dairy cows from Heilongjiang Province, China     

Yulong Zhou  Yachao Ren  Chunling Fan  Hong Shao  Zecai Zhang  Wenbin Mao  Chunbo Wei  Hongbo Ni  Zhanbo Zhu  Xilin Hou  Fanze Piao  Yudong Cui 《Tropical animal health and production》2013,45(8):1709-1714

A survey of the prevalence rate, pathogenic subspecies, and risk factors of mycotic mastitis in dairy cows from Heilongjiang Province, China, was conducted. Milk samples from 412 cows with chronic mastitis were collected and cultured on 8 % sheep blood agar, MacConkey agar, and Sabouraud agar with chloramphenicol. Counting of the morphologically distinct colonies was performed, as well as the isolation and identification of organisms through phenotypical and physiological criteria. Four hundred seventy-eight aerobic microorganisms were isolated. Yeasts and yeast-like fungi 35.6 % (170/478) and bacteria 64.4 % (308/478) were isolated. The fungal isolates were identified as Candida (79.4 %), Trichosporon (5.9 %), Aspergillus (7.1 %), Cryptococcus (2.4 %), and Rhodotorula (4.1 %). More than ten species of yeast were isolated including Candida krusei 50/135 (37 %), Candida rugosa 16/135 (11.9 %), and Candida lusitaniae 15/135 (11.1 %). A higher positivity (18.5 and 56.3 %) (P ≤0.05) was observed in cows from environmental temperatures of 0–15 and 15–35 °C than those at <0 °C and in cows affected by the disease for >45 and 30–45 days compared with cows suffering 10–30 days. Meanwhile, a statistically significant difference (44.9 vs. 31.4 %) (P ≤0.05) was observed under extensive raising systems vs. intensive raising systems. It appears that Candida is a major pathogen of mycotic mastitis of dairy cows. Extensive raising system, high environmental temperature (15–35 °C), and the duration of the disease (>30 days) were important risk factors of the incidence of mycotic mastitis. Here, we provide a theoretical foundation for research into preventing and treating mycotic mastitis of dairy cows in China.  相似文献   

百脉根不定根发育相关基因LcC2DP1的克隆与功能初步分析     

马思宇  肖芳斌  罗雪  韦飘  宋莉 《华中农业大学学报》2023,42(1):42-50

为研究百脉根（Lotus corniculatus L.）C2钙依赖蛋白激酶基因LcC2DP1在不定根形成过程中的功能,通过RACE法从百脉根中克隆LcC2DP1基因,利用qRT-PCR检测其时空表达模式,并通过农杆菌介导的瞬时表达系统在百脉根中过量表达LcC2DP1并鉴定其功能。结果显示：LcC2DP1基因全长705 bp,编码235个氨基酸,分子质量为25.95 ku,与蒺藜苜蓿同源性最高（82%）;在百脉根不定根分化过程中持续表达,表达部位为根、茎和叶片;与野生型亲本（WT）相比,转LcC2DP1基因百脉根（TP）的不定根分化提前1~2 d;在不定根分化的9~15 d ,其总根长分别是WT的168%、155%,根体积分别是WT的249%、161%,根尖数分别是WT的156%、137%。TP百脉根的总根长（P<0.01）、根体积（P<0.01）和根尖数（P<0.05）表现出一定的发育优势,表明LcC2DP1基因可能与百脉根不定根发育调控相关。  相似文献   

从江县鲤爆发性死亡病例实验室诊断     

胡安东  贺欣薇  杨霞  张飘  程振涛  姜海波  文明 《中国动物传染病学报》2019,(4):75-82

2018年10月贵州省从江县某水产养殖专业合作社鲤爆发死亡,本研究对死亡病例进行了流行病学调查、病理学观察、寄生虫学检查、细菌分离鉴定和病毒PCR检测等诊断。结果显示:病鲤病变以鳃丝溃烂、体表出血、肛门红肿和眼球凹陷为主要特征,组织的主要病变是肾小球萎缩出血、肾小囊空腔、鳃丝肿胀粘连及上皮细胞脱落等;细菌分离培养可得到圆形凸起、表面光滑的灰白色菌落,经染色镜检、生理生化鉴定和16S rRNA基因测序分析,鉴定该分离菌为嗜水气单胞菌;PCR检测显示鲤浮肿病毒(Carp edema virus,CEV)为阳性,未检出鲤春病毒血症病毒(Spring viremia of carp virus,SVCV)和鲤疱疹病毒(Koi herpesvirus,KHV);显微镜观察亦未见到寄生虫虫体;分别取分离菌和鲤浮肿病毒阳性病例组织悬液进行人工感染试验,均可引起健康鲤发生死亡。上述结果表明,从江县鲤的死亡是嗜水气单胞菌和鲤浮肿病毒混合感染所致。  相似文献   

试论原条合理造材   总被引：1，自引：0，他引：1  

朴世一  穆叶久 《森林工程》1999,(5)

本文论述和分析了我国原条合理造材技术的发展和研究情况,归纳和探讨合理造材方法。  相似文献   

新型低压绝缘分裂导线供电模式的实施与展望   总被引：14，自引：2，他引：12  

朴在林  周启龙  纪建伟  张秀然  张俊亮 《农业工程学报》1999,15(4):172-176

针对目前低压电网普遍存在的电能损耗偏高、电压质量差及窃电严重等问题,研制一种新型低压绝缘分裂导线,并基于该导线结构特点提出了供电新模式。示范区二年多的实施结果表明,其经济社会效益显著,对减轻农民电费负担、节支增效有重要的实际意义。  相似文献   

烤烟新品种优质、适产性的初步研究   总被引：1，自引：0，他引：1  

朴哲浩  俞昌元  朴哲义 《延边大学农学学报》1999,(1)

品种“云８５”产值最高,品种９５３０４、９５３０９分别位于第二、第三．３个品种外观质量都与２个对照相仿,化学成分协调．评吸鉴定结果品种９５３０４、９５３０９都优于“云８５”,相近主对照ＮＣ８９,优于副对照Ｋ３２６．  相似文献   

克百威、丁硫克百威和丙硫克百威登记现状及其潜在风险关注分析   总被引：1，自引：0，他引：1  

朴秀英  吕宁  林荣华  宗伏霖  刘学 《农药科学与管理》2015,(4):10-16

本文介绍了克百威、丁硫克百威和丙硫克百威登记和管理现状,分析了蔬菜、水果、食用菌和茶叶中克百威残留监测及残留超标原因,比较了各国(地区组织)的克百威最大残留限量,阐述了美国和欧盟国外对水生生物和鸟类风险评估结论,提出了风险评估与管理方面的建议。  相似文献   

固相萃取-气相色谱方法测定水中毒死蜱含量的不确定度评定   总被引：1，自引：0，他引：1  

周艳明  朴秀英  王晓军  姜辉  魏启文 《农药科学与管理》2015,36(7)

本文建立了利用固相萃取-气相色谱法测定水中毒死蜱含量的方法,通过数学模型分析并计算了检测过程中的不确定度分量,并计算出相对扩展不确定度。  相似文献   

基于改进蚁群算法的农网送电线路设计路径寻优     

李鹏  朴在林  王剑委 《农业工程学报》2009,25(11):232-235

送电线路的路径选择是线路设计中的重要环节,直接影响工程总造价及运行可靠性。该文针对送电线路选择路径的特点,建立全局最优路径的搜索模型,形成简单的连通图,并对基本蚁群算法的选择策略及信息素更新进行改进,同时考虑了地质状况、水文情况及林带征地等对线路路径选择的影响,最后利用改进的算法直接在模型上进行全局最优路径搜索。仿真结果表明,此方法可以准确地搜索到送电线路的全局最优路径。  相似文献   

Lysine restriction and realimentation affected growth,blood profiles and expression of genes related to protein and fat metabolism in weaned pigs     

Y. X. Yang  J. Guo  Z. Jin  S. Y. Yoon  J. Y. Choi  M. H. Wang  X. S. Piao  B. W. Kim  B. J. Chae 《Journal of animal physiology and animal nutrition》2009,93(6):732-743

To investigate the effects of lysine restriction and subsequent realimentation on growth performance, blood profiles and gene expression of leptin and myostatin, 128 weaned pigs [initial body weight (BW) 6.96 ± 1.07 kg, 26 ± 2 days of age] were randomly allotted to four treatments. The starter diets during the first 2 weeks (P1) contained 100%, 80%, 70% or 60% of recommended lysine levels ( National Research Council, 1998 ). Then, common grower 1 and 2 diets were offered for 2 weeks (P2 and P3) each. During P1, average daily gain (ADG) was linearly reduced (p < 0.05) with the increasing levels of lysine restriction. Growth rate was greater in pigs previously fed lysine‐restricted diets than well‐fed pigs although it did not reach a significant level during realimentation. However, the final BW and overall ADG were the lowest (p < 0.05) and F/G was poor in pigs fed 60% lysine diet. Relative visceral organ weights and composition of skeletal muscle were similar (p > 0.05) among the treatment. Blood triglyceride and glucose levels were increased (p < 0.05) during P1, while blood urine nitrogen, total protein and albumin levels were decreased (p < 0.05) during P2 with the reduction in dietary lysine levels. The abundance of myostatin mRNA in skeletal muscle and leptin mRNA in subcutaneous adipose tissue were lower (p < 0.05) in lysine‐restricted pigs than in pigs fed non‐restricted diets. In conclusion, 80% and 70% lysine restriction of starter diets resulted in inferior growth and compensatory growth effect was noted during realimentation, while 60% lysine restriction had a negative influence on growth performance. Moreover, the changes in myostatin and leptin mRNA abundance caused by nutritional manipulations may be involved in the regulation of protein and fat deposition in young pigs.  相似文献