Escherichia coli challenge and one type of smectite alter intestinal barrier of pigs

An experiment was conducted to determine how an E. coil challenge and dietary clays affect the intestinal barrier of pigs. Two groups of 32 pigs （initial BW： 6.9 ± 1.0 kg） were distributed in a 2 x 4 factorial arrangement of a randomized complete block design （2 challenge treatments： sham or E. coil, and 4 dietary treatments： control, 0.3% smectite A, 0.3% smectite B and 0.3% zeolite）, with 8 replicates total. Diarrhea score, growth performance, goblet cell size and number, bacterial translocation from intestinal lumen to lymph nodes, intestinal morphology, and relative amounts of sulfo and sialo mucins were measured. The E. coli challenge reduced performance, increased goblet cell size and number in the ileum, increased bacterial translocation from the intestinal lumen to the lymph nodes, and increased ileal crypt depth. One of the clays （smectite A） tended to increase goblet cell size in ileum, which may indicate enhanced protection. In conclusion, E. coli infection degrades intestinal barrier integrity but smectite A may enhance it.     

不同饲养方式中蜂形态学初探

对饲养在圆木桶、墙洞、活框蜂箱中10年以上的中蜂蜂群进行工蜂标准采集,测定其工蜂的40个形态指标,对比分析吻长等9个与生产力相关的指标,结果表明,对圆木桶、墙洞、活框蜂箱三种饲养方式进行人为干预,能使中蜂蜂群与生产力相关的形态指标得到优化。     

Seroprevalence of subtype H3 influenza A virus in South Korean cats

To investigate the potential transmission of subtype H3 influenza virus to cats, a serological survey was carried out in South Korea. Serum samples (n = 1027) were obtained from 809 pet cats and 218 domesticated cats living in urban colonies (D-cats) from 2008 to 2010, and tested using an influenza anti-nucleoprotein (NP)-specific enzyme-linked immunosorbent assay (ELISA) and the haemagglutination inhibition (HI) test, which was recommended by the World Organization for Animal Health. Anti-influenza virus antibodies were detected in 3.12% and 2.43% of cat sera tested using the NP-specific ELISA and HI test, respectively. Anti-H3 antibodies were also identified when the HI assay was used for influenza virus serotyping. These data may indicate the sporadic transmission of subtype H3 influenza virus from other infected species to cats in South Korea.     

牛血清中口蹄疫病毒非结构蛋白抗体时间分辨荧光免疫分析检测方法的建立

为研究快速定量检测牛血清中口蹄疫病毒非结构蛋白抗体的方法,试验通过优化抗原表达条件等步骤,在大肠杆菌原核表达系统中表达可溶性的3A-3B融合蛋白,并基于纯化的可溶性融合蛋白建立口蹄疫病毒非结构蛋白抗体时间分辨荧光免疫分析检测试剂盒。结果表明:建立的方法能够检测牛血清中的口蹄疫病毒非结构蛋白抗体,敏感性高,特异性强,对其他相关的牛类病原无交叉反应,其组内与组间变异系数分别低于10%和15%,具有良好的重复性。对300份临床牛血清样品进行检测,同Procheck公司的口蹄疫非结构蛋白抗体试剂盒进行比较,阳性样品符合率96%,阴性样品符合率93.3%,总的符合率95.7%。重复性试验组内与组间变异系数均小于10%。文章首次建立了口蹄疫病毒非结构蛋白抗体时间分辨荧光免疫分析检测方法,同传统的ELISA方法相比,该检测方法特异性相当、敏感性更高,操作更简单、快速,具有较高的应用推广价值。     

Seroprevalence of chlamydial infection in dairy cattle in Guangzhou, southern China

Chlamydia spp. are obligate intracellular gram-negative bacteria that cause a wide range of significant diseases in humans and animals worldwide, resulting in significant economic losses. Chlamydial infection in cattle has been reported in many countries including China. However, there has been no survey of chlamydial infection of dairy cattle in Guangzhou, southern China. The objective of the present investigation was to examine the chlamydial seroprevalence in dairy cattle in Guangzhou, subtropical southern China by using an indirect hemagglutination assay (IHA). The overall seroprevalence of chlamydial infection in dairy cattle was 7.25% (29/400). Greater than or equal to eight-yr-old dairy cattle had the highest seroprevalence (10.34%), followed by those that were ≥ 6 years old or < 7 years old dairy cattle (10.20%), although there were no statistically significant differences among different groups (P > 0.05). Dairy cattle with 5 pregnancies had the highest seroprevalence (10.81%). These results indicate that chlamydial infection was present in dairy cattle in Guangzhou, subtropical southern China, and integrated strategies and measures should be executed to control and prevent chlamydial infection and disease outbreak in the study region.     

复合蛋白饲料替代豆粕饲喂蛋鸡作用效果

豆粕以其良好的营养特性．被誉为“植物性蛋白质饲料之王”．它与“动物性蛋白质饲料之王”鱼粉和“能量饲料之王”玉米组合的日粮是最佳配方,因为,三者可以相互取长补短．使日粮中各种氨基酸基本达到平衡,因此．豆粕在蛋白质饲料中的应用占有较大的比例,在很大程度上影响着畜禽饲料的成本。     

赖氨酸产业生存调查：经销商的过去、现状以及未来

近10年以来．中国赖氨酸工业蓬勃发展,一些生产商也发展壮大．涌现了像大成生化等全球性主要生产商．中国赖氨酸出口由本世纪初的不足千吨水平发展到2008年的15万t左右,8年增长达到150倍以上：而国内需求也由开始的10万t左右增长至2008年的25万t以上。