甘露寡糖、中药和微生态制剂对肉鸡抗氧化性能的影响

1992只1日龄AA肉鸡随机分为4个处理组，饲喂四种不同的日粮。42日龄测定各组肉鸡组织及血清抗氧化指标的水平。结果表明：（1）除心脏和血清外，各试验组MDA含量均与Ⅳ组差异显著（P〈O．05）。（2）肝脏中SOD变化较明显，各试验组均高于Ⅳ组，且差异显著（P〈O．05）。心脏各组之间差异不显著。（3）心脏GSH—Px含量以Ⅱ、Ⅲ组较高，且均与Ⅳ组差异显著。血清以Ⅱ组最高，且与其他各组之间差异显著（P〈0．05）。（4）心脏T—AOC含量变化较大，各试验组均高于Ⅳ组，且差异显著（P〈0．05）。血清以Ⅱ组最高，且与其他试验组差异显著（P〈0．05）。     

Isolation,Identification and Biological Characteristics of Staphylococcus chromogenes from Tibetan Pigs

In order to understand the infection of Staphylococcus disease in healthy Tibetan pigs in Linzhi city,Tibet.232 samples were collected from the slaughterhouse in Bahe town,Gongbujiangda county,Linzhi city,Tibet,the teaching practice ranch at the Tibet Agriculture and Animal Husbandry University in Bayi district,Linzhi city,and the slaughterhouse in Bayi district,Linzhi city.These samples were isolated,cultured and identified,and one isolated strain was systematically studied for biological characteristics.Epidemiological survey results showed that 73 of 232 samples were positive for Staphylococcus,the positive rate was 31.47%,16 positive samples were detected in the slaughterhouse of Bahe town,Gongbujiangda county,Linzhi,Tibet,with a detection rate of 23.89%(16/67),43 positive samples were detected in the pastures of the teaching practice ranch at the Tibet Agriculture and Animal Husbandry University in Bayi district,Linzhi city,with a detection rate of 34.40% (43/125),14 positive samples were detected in the slanghterhouse in Bayi district,Linzhi city,with a detection rate of 35.00% (14/40).Through PCR identification,gene sequencing and biochemical identification,5 strains of Staphylococcus chromogenes were isolated,and one of them (Sa LZ1) was studied systematically.The biological characteristics of the isolated strains showed that the Sa LZ1 strain formed round white convex colonies on the agar medium,with regular edges,smooth surfaces,and opaque white colonies.The isolates were Gram-positive cocci bacteria.PCR sequencing results showed that the isolate had the highest homology with Staphylococcus chromogenes (GenBank accession No.:MG576253.1),positive for serum inulin,manicol,glucose,saccharose,lactose,negative for arabinose,sodium hippurate,raffinose,xylose,urea,etc,consistent with the biochemical characteristics of Staphylococcus chromogenes.The logarithmic growth period of isolated bacteria was 5 to 10 h.The pathogenicity test of mice showed that the mortality rate of mice reached 100% when the concentration of Sa LZ1 strain reached 3.5×10⁹ CFU/mL.And the results of pathological section showed that Sa LZ1 strain could cause the visceral tissue of mice to develop pathological changes.The above results provided a theoretical basis for the prevention and control of Staphylococcus suis in Linzhi,Tibet.     

啤酒酵母葡聚糖对断奶仔猪生产性能及淋巴细胞转化率的影响

为了探讨啤酒酵母葡聚糖在断奶仔猪日粮中的适宜添加剂量及其对断奶仔猪细胞免疫功能的影响,本研究进行了2个试验。试验1选用100头(28±2)d断奶的二元杂交断奶仔猪,按单因子试验设计随机分为5个处理,分别饲喂含葡聚糖0、25、50、100mg/kg和200mg/kg的日粮。结果表明:随葡聚糖添加剂量的增加,平均日增重在14￣28 d及0￣28 d呈二次曲线变化(P<0.05)。试验2选用80头(28±2)d断奶的二元杂交断奶仔猪,随机分为2个处理,分别饲喂含葡聚糖0mg/kg和50mg/kg的日粮。在试验的第14天和第28天,每重复取1头仔猪前腔静脉采血,测定外周血淋巴细胞转化率。结果显示,在断奶仔猪日粮中添加50mg/kg葡聚糖提高了仔猪在14￣28d及0￣28d的日增重(P<0.05)。而且,也提高了仔猪在0￣14 d、0￣28 d及28￣35 d的平均日采食量(P<0.05)。但是对淋巴细胞转化率没有影响。结果表明:在断奶仔猪日粮中添加50mg/kg啤酒酵母葡聚糖,可以提高断奶仔猪的生产性能,而且没有性别差异。     

Insulin like growth factor-1 protects c17.2 neural stem cells against radiation-induced injury

AIM:To investigate the protective effect of insulin like growth factor-1 (IGF-1) against radiation-induced injury in c17.2 neural stem cells.METHODS:c17.2 neural stem cells were cultured in vitro and identified by nestin immunohistochemistry and X-gal staining.The IGF-1 adenoviral vector was transfected into c17.2 neural stem cells.The expression of IGF-1 was detected by IGF-1 immunohistochemistry.Necrosis and apoptosis of c17.2 neural stem cells were induced by radiation at doses of 4 Gy,6 Gy and were detected by flow cytometry and TUNEL test.The effect of IGF transfection on the degree of necrosis and apoptosis in these cells was also observed.RESULTS:c17.2 cells were identified by nestin and X-gal staining.Immunohistochemistry verified the expression of IGF-1 in the c17.2 neural stem cells transfected with adenoviral vector.At the same doses of radiation,the rates of apoptosis and necrosis in c17.2 neural stem cells transfected with IGF-1 were lower than those in the cells without IGF-1 adenoviral vector transfection.CONCLUSION:The rate of necrosis and apoptosis of c17.2 neural stem cells induced by radiation is decreased by transfection of IGF-1 adenoviral vector.IGF-1 shows a protective effect on c17.2 cells.     

《科技导报》（半月刊）欢迎订阅、欢迎投稿、欢迎刊登广告

AIM: To study the effects of ultraviolet (UV) on mitochondrial functions and apoptosis in HaCaT cells. METHODS: After irradiation by UV at low dose (UVA 2 J/cm2，UVB 10 mJ/cm2) and high dose (UVA 6 J/cm2，UVB 30 mJ/cm2), HaCaT cells were cultured for 15 hours. Flow cytometry was used to measure mitochondrial membrane potential, mitochondrial mass and apoptotic rate. Annexin V-FITC/PI staining of apoptotic cells was analyzed by laser confocal microscopy. RESULTS: After UV irradiation, cell proportion with low mitochondrial membrane potential increased with irradiation doses. The proportion of control group, low dose group and high dose group were 7.94%±1.02%, 25.87%±4.55% and 39.27%±5.32%, respectively. Cells proportion with low mitochondrial mass increased with irradiation doses. The proportion of control group, low dose group and high dose group were 15.19%±1.58%, 40.36%±4.41% and 68.79%±5.46%, respectively. The hypodiploid peaks of DNA content analysis represented the apoptotic rate of HaCaT cells. The apoptotic rate of control group, low dose group and high dose group were 1.82%±0.51%, 30.16%±5.47% and 58.49%±5.98%, respectively. To analyze the cells apoptosis by staining with annexin V-FITC and PI, the results were consistent with those of DNA content analysis. Cells in control group showed almost no positive staining cells. Single annexin V-FITC positive cells in low dose group and double positive cells in high dose group were predominant, respectively. CONCLUSION: UV irradiation induces HaCaT cell mitochondrial depolarization, as well as mitochondrial mass loss. These changes are related to cell apoptosis.     

鸡β-防御素在大肠杆菌中的高效表达及复性

鸡β-防御素(gallinacin-3,Gal3)是鸡体内重要的防御因子,本试验研究了鸡Gal3融合蛋白在大肠杆菌中高效表达的规律,并探索了重组蛋白质的复性工艺.结果表明,加入诱导剂后1h,开始有可检出量的重组蛋白质表达,2h的表达水平已接近最大量;化学诱导剂IPTG 0.2～1.2mol/L对重组蛋白的产量没有明显影响.经Lablmage软件分析,融合蛋白的产量可达菌体总蛋白的35%以上,且主要以包涵体形式存在.将所获包涵体用8mol/L尿素溶解后,分步稀释于含有氧化型谷胱甘肽和还原型谷胱甘肽的复性系统中,重组蛋白得到完全复性.12mg/L复性的重组鸡Gal3能抑制肠炎沙门氏菌的生长,24mg/L能抑制肠致病型大肠杆菌的生长.     

附睾功能及其对精子成熟的影响

哺乳动物的附睾为精子的成熟提供了特殊的微环境，是精子成熟、保护、运输和贮存的部位，在生殖过程中起着重要作用。附睾上皮细胞的合成、分泌、转运等功能使精子发生了一系列结构、生化和功能的改变．从而使精子获得受精和运动能力。作者对附睾的形态结构、功能和对精子成熟影响研究现状等作简要综述。     

二重PCR检测鸭瘟病毒和鹅细小病毒的初步研究

根据鸭瘟病毒(Duck plague virus,DPV)DNA聚合酶基因和鹅细小病毒(Goose parvovirus,GPV)NS基因序列分别设计2对引物,应用这2对引物对混合样品中鸭瘟病毒和鹅细小病毒进行了二重PCR扩增。PCR产物的琼脂糖凝胶电泳结果表明2条特异性带为563bp(DPV)和1146bp(GPV),与实验设计相符,且与常规单一PCR结果一致。二重PCR反应检测出的DPV含量相当于20个PFU;检测出的GPV含量相当于0.1个ELD50,对禽痘病毒和减蛋综合征病毒的核酸未能扩增出任何条带,特异性良好。该二重PCR能够在一次扩增反应中检测两种病毒,为两种鹅病的病原检测和诊断提供了一种简便、经济、快速的手段。