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971.
972.
Duan H Chai T Müller W Zucker BA 《Berliner und Münchener tier?rztliche Wochenschrift》2006,119(1-2):40-44
Concentration of airborne endotoxins, airborne aerobic bacteria and airborne aerobic gram-negative bacteria were measured in 3 rabbit houses. Further, the species composition of the airborne gram-negative bacterial flora was investigated. The total amount of airborne endotoxin ranged from 22 to 774 EU/m3 (Endotoxin Units/m3). The number of total airborne aerobic bacteria varied between 780 and 20100 CFU/m3, the number of airborne aerobic gram-negative bacteria between 39 and 1030 CFU/m3. Most gram-negative bacterial isolates belonged to the family Enterobacteriaceae with E. coli as primary species. In two rabbit houses also airborne Pasteurella multocida spp. multocida, the most common respiratory pathogen of rabbits, was isolated. 相似文献
973.
974.
为掌握布鲁氏菌病活疫苗(M5-90株)免疫后的绵羊抗体水平、消长情况和不良反应发生情况,选择育肥羊和怀孕母羊各100只,分别用皮下注射免疫和点眼免疫法,开展了3个月的跟踪观察和定期检测。结果表明:布鲁氏菌病活疫苗(M5-90株)对育肥羊注射免疫后15 d的平板凝集抗体转阳率达100.0%,90 d降至22.7%;点眼免疫后15 d的平板凝集抗体转阳率达85.4%,90 d日降至0;个别3月龄以下育肥羊对注射免疫和点眼免疫均会发生一定程度不良反应,甚至死亡。活疫苗(M5-90株)对怀孕母羊皮下注射免疫后15 d的平板凝集抗体转阳率达100%,90 d降至14%;点眼免疫后15 d的平板凝集抗体转阳率达95.9%,90 d降至6.4%;注射免疫和点眼免疫均能造成一定比例的母羊流产和其他不良反应。因此,布鲁氏菌病活疫苗(M5-90株)不宜用于3月龄以下羔羊和怀孕母羊的免疫。 相似文献
975.
976.
Jie Zhang Jie Chai Zonggang Luo Hang He Lei Chen Xueqin Liu Qinfei Zhou 《Animal Science Journal》2018,89(1):202-210
Crossbreeding is an effective method of improving the efficiency and profit of production in commercial pig operations. To understand the effect of crossbreeding on meat and nutrient quality, a combination including three purebred (Duroc, D; Landrace, L; Yorkshire, Y) and two crossbred pig lines (Landrace × Yorkshire, LY; Duroc × (Landrace × Yorkshire), DLY) frequently used internationally were studied. The results showed that meat from the LY and DLY crosses had lower values for lightness , shear force and epinephrine and higher values for drip loss, C18:1, insulin, glucagon and monounsaturated fatty acids than D, L and Y pigs. Moreover, LY had higher values for post mortem pH and lower values for a* and b* than the purebreds. In contrast, DLY had lower values for pH and higher values for a* and b* than the purebreds. Meat quality‐related gene analysis showed that the CAST, IGF2 and MC4R gene expression levels in the LY and DLY pigs were significantly higher than those in the D, L and Y pigs. These results indicate that crossbreeding can alter the meat quality, nutritive value, energy metabolism and gene expression of pigs. Future research should focus on microRNA expression and DNA methylation that regulate gene expression and thus affect the meat quality. 相似文献
977.
Y. Merbl A. Sommer O. Chai I. Aroch G. Zimmerman A. Friedman H. Soreq M.H. Shamir 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2014,28(6):1775-1781
Background
Idiopathic and acquired epilepsy are common in dogs. Up to 30% of these dogs are refractory to pharmacological treatment. Accumulating experimental evidence indicates that brain immune response and presence of inflammatory mediators decrease the threshold for individual seizures and contribute to epileptogenesis.Hypothesis
Dogs with seizures have higher cerebrospinal interleukin‐6 (IL‐6) and tumor necrosis factor‐α (TNF‐α) concentrations compared to dogs with no seizures.Methods
A prospective double blinded study; cerebrospinal fluid (CSF) and serum IL‐6, TNF‐α and total protein (TP) concentrations were measured by a blinded investigator for the study group and CSF IL‐6 and TNF‐α levels and TP concentrations were measured in the control group (CG).Animals
Dogs presented with seizures that had enough CSF collected to allow analysis were included in the study group. Twelve apparently healthy, quarantined, stray dogs served as control (CG).Results
Cerebrospinal fluid TNF‐α and IL‐6 concentrations were significantly higher (P = .011, P = .039) in dogs with seizures (0 ± 70.66, 0.65 ± 10.93 pg/mL) compared to the CG (0 ± 19, 0.73 ± 0.55 pg/mL). When assessing cytokine concentrations of specifically the idiopathic epilepsy (IE) dogs compared to the CG, only TNF‐α concentrations (8.66 ± 62, 0 ± 19 pg/mL) were significantly higher (P = .01). CSF TP concentrations were not significantly higher in the study dogs compared to the CG.Conclusions and Clinical Importance
Higher TNF‐α and IL‐6 concentration in the CSF of dogs with naturally occurring seizures. The higher supports the hypothesis that inflammatory processes through certain mediators play a role in the pathogenesis of seizures in dogs. 相似文献978.
979.
Hu Zuqing Chai Ruirui Liu Xin Dong Yao Su Dan Desneux Nicolas Tan Xiaoling Luo Chen 《Journal of pest science》2022,95(3):1273-1285
Journal of Pest Science - Evolution of the spread strategies of plant pathogens may be described using the vector manipulation hypothesis (VMH), which posits that pathogens can enhance their... 相似文献
980.
我校公共选修课现状及其应对分析 总被引:11,自引:0,他引:11
本文通过我校开设公共选修课的实践经验,阐述了校级选修课在培养大学生科学文化素质方面所起到的重要作用,以及现阶段我校公共选修课面临的各种问题。并针对所出现的问题提出解决措施。 相似文献