Experimental studies with foot-and-mouth disease virus type Asia-1, responsible for the 2005 epidemic in China

This study was carried out to investigate the biological characteristics of the foot-and-mouth disease (FMD) virus strain Asia-1 China/2005, which is responsible for the 2005 epidemic in China. The result showed that this strain is not host restricted, and could not only cause FMD in cattle and sheep but also in pigs by either inoculation or direct contact.     

甜菜碱对奶牛采食量、泌乳性能和血液指标的影响

选用20头体重(597±11.8)kg、泌乳天数(88±4.5)d、日产奶(26.3±0.5)kg的经产奶牛,随机分为4组,采用4×4拉丁方设计,研究甜菜碱(0、50、100和150g/d)对泌乳早期奶牛采食量、泌乳性能和血液指标的影响。结果表明:日粮添加甜菜碱对奶牛的采食量、乳蛋白率、乳糖率和血糖浓度无显著影响,100g/d组和150g/d组鲜奶产量显著高于对照组和50g/d组(P<0.05);100g/d组和150g/d组4%乳脂校正乳、能量校正乳和乳脂产量显著高于对照组(P<0.05);100g/d组乳脂率显著高于对照组(P<0.05);100g/d组和150g/d组血浆游离脂肪酸和β-羟丁酸浓度显著低于对照组(P<0.05)。根据以上结果推断,甜菜碱的适宜添加水平为100g/d。     

城区宠物防疫管理

合肥是安徽的省会城市,随着人民生活水平的提高,城区养犬数量急剧增加,现仅合肥二环以内就有犬5万只左右。部分市民不文明养犬,随意遗弃犬,使得流浪犬数量增加,造成犬病的传播。一些动物诊所和宠物     

乳牛舍内环境空气中细菌数量与乳房炎的关系研究

采用自然沉降法对规模化泌乳奶牛舍内消毒前后空气细菌含量进行检测,同时对泌乳牛群进行乳房炎调查,对乳房炎奶牛乳汁中病原菌分离鉴定。结果表明,不同的牛舍不同的培养基其结果均不相同,NA培养基菌落数最高达77.8×103cfu/m3,S.S培养基在多个分布点无细菌生长。牛舍经过消毒后环境空气中的细菌总数大幅度减少,运动场空气细菌总数明显低于舍内。奶牛乳房炎的发生率与牛舍环境空气中的细菌总数呈正相关,细菌总数多的牛舍奶牛乳房炎的发病率也高。环境空气中和乳房炎奶牛乳汁中同时分离到金黄色葡萄球菌、大肠杆菌、伤寒沙门氏菌、肺炎克雷伯氏菌等。     

铁骑力士“煮酒论英雄”——2010年铁骑力士集团战略发展论坛暨核心客户年会隆重召开

<正>腊梅吐芬芳,冬尽春将至。1月15-16日,2010年铁骑力士集团战略发展论坛暨核心客户年会在四川省绵阳市新落成的总部学术报     

Source of fiber influences growth,immune responses,gut barrier function and microbiota in weaned piglets fed antibiotic-free diets

This study examined the impacts of different fiber sources on growth, immune status and gut health in weaned piglets fed antibiotic-free diets. Sixty piglets (BW = 8.18 ± 1.35 kg) were assigned to 3 dietary treatments based on BW and gender in a randomized complete block design (5 replicates/treatment and 4 piglets [2 barrows and 2 gilts]/replicate): (1) an antibiotic-free diet (control, CON); (2) CON + 6% wheat bran (WB); (3) CON + 4% sugar beet pulp (SBP). Dietary WB supplementation tended to increase ADG compared with CON from d 1 to 14 (P = 0.051) and from d 1 to 28 (P = 0.099). Supplementation of WB increased (P < 0.05) G:F compared with CON and SBP from d 1 to 14 and from d 1 to 28. Compared with CON, the addition of WB reduced (P < 0.05) diarrhea rate from d 1 to 14 and tended (P = 0.054) to reduce diarrhea rate from d 1 to 28. The addition of WB decreased (P < 0.05) serum diamine oxidase activity on d 14, and up-regulated (P < 0.05) ileal mRNA levels of occludin on d 28 when compared with CON. Piglets fed WB showed decreased (P < 0.05) serum interleukin-6 levels compared to those fed SBP and decreased (P < 0.05) ileal interleukin-8 levels compared to those fed CON and SBP on d 28. Supplementation of WB increased (P < 0.05) serum levels of immunoglobulin A (IgA), IgG and IgM compared with SBP on d 14, and increased (P < 0.05) the levels of serum IgA and ileal sIgA compared with CON and SBP on d 28. Piglets fed WB showed an enhanced (P < 0.05) α-diversity of cecal microbiota than those fed SBP, while piglets fed SBP showed reduced (P < 0.05) α-diversity of cecal microbiota than those fed CON. Compared with CON, the addition of WB elevated (P < 0.05) the abundance of Lachnospira and cecal butyric acid level. Piglets fed WB also showed increased (P < 0.05) abundances of Lachnospira and unclassified_f_Lachnospiraceae compared with those fed SBP. Collectively, the supplementation of WB to antibiotic-free diets improved performance, immune responses, gut barrier function and microbiota compared with the CON and SBP fed piglets. Therefore, supplementing weaned piglets with WB was more effective than SBP.     

Inactivation of the Wnt/β-catenin signaling contributes to the epithelial barrier dysfunction induced by sodium oxalate in canine renal epithelial cells

High oxalate consumption has been recognized as a risk factor for renal calcium oxalate stones in companion animals (dogs and cats). However, the cellular signaling involved in oxalate-induced dysfunction in renal tubular epithelial cells remains not fully elucidated. In this study, Mardin–Darby canine kidney (MDCK) cells, an epithelial cell line derived from canine kidney tubule, were tested for cell proliferation activity and barrier function after being exposed to sodium oxalate (NaOx). Further, the involvement of Wnt/β-catenin in NaOx-induced renal epithelial barrier dysfunction was evaluated. MDCK cells treated with NaOx exhibited reduction in cell proliferation and migration. Besides, NaOx exposure led to a decrease in transepithelial electrical resistance and an increase in paracellular permeability. The deleterious effects of NaOx on epithelial barrier function were related to the suppressed abundance of tight junction proteins including zonula occludens, occludin, and claudin-1. Of note, protein levels of β-catenin and phosphorylated (p)-β-catenin (Ser552) in MDCK cells were repressed by NaOx, indicating inhibitory effects on Wnt/β-catenin signaling. An inhibition of glycogen synthase kinase-3β (GSK-3β) by SB216763 enhanced the abundance of β-catenin and p-β-catenin (Ser552), and protected against epithelial barrier dysfunction in NaOx-treated MDCK cells. The results revealed a critical role of Wnt/β-catenin signaling in the epithelial barrier function of MDCK cells. Activation of Wnt/β-catenin signaling might be a potential therapeutic target for the treatment of oxalate-linked renal stones.     

动物组织碱水解处理技术的研究进展

碱水解是近年来发展起来的一种动物组织处理技术,通过NaOH或KOH等碱性物质在高温高压条件下催化动物组织水解为无害的固体残渣和废液并实现组织的灭菌和分解,具有彻底灭活病原微生物、不产生有害气体、操作简单、费用低廉等优点。本文从原理、应用及研究进展等方面,综述了碱水解处理技术的发展与现状。比较分析了碱水解相对于传统组织处理方法的优势,介绍了组织处理机的类型、存在的问题和未来发展趋势。     

BCG诱导RAW264.7细胞脂肪酸氧化对细胞自噬和促炎因子表达的调控作用

旨在探究脂肪酸氧化（fatty acid oxidation,FAO）对BCG介导的RAW264.7细胞自噬和促炎因子表达的调控作用。用BODIPY染色和游离脂肪酸定量试剂盒检测BCG感染后RAW264.7细胞中脂滴聚集情况以及脂肪酸含量;Western blot检测BCG感染对肉毒碱棕榈酰基转移酶1A （CPT-1A）表达的影响;Etomoxir （100 μmol·L^-1）预处理细胞2 h后,BCG感染细胞6 h,检测RAW264.7细胞中BCG存留量,并用Western blot方法检测自噬相关蛋白（Beclin1、LC3-II）和溶酶体蛋白（Rab7）的表达情况;用免疫荧光方法和mRFP-GFP-LC3荧光双标腺病毒分别检测自噬小体聚集和自噬流;荧光定量PCR和ELISA分别检测促炎因子IL-1β、IL-6和TNF-α mRNA表达情况以及在细胞培养上清中的含量。结果显示,BCG感染促进RAW264.7细胞中脂滴聚集和CPT-1A的表达,而游离脂肪酸含量降低;Etomoxir预处理抑制了细胞中BCG存活,并上调了Beclin1、LC3-II和Rab7表达,且细胞中出现大量自噬小体聚集,自噬流增强,却抑制了促炎因子IL-1β、IL-6和TNF-α mRNA表达与分泌。综上表明,抑制FAO可促进BCG感染诱导的RAW264.7细胞自噬,并抑制BCG感染引起的炎症反应。     

饲用荞麦在畜牧业中的应用与研究

荞麦(Fagopyrum esulentum)原产于中国,其栽培种甜荞和苦荞在世界各地已被广泛种植,我国西南地区蕴含着丰富的野生荞麦资源。荞麦营养丰富,除含有常见的蛋白质、纤维素和糖类外,还富含芦丁等抗氧化物质,具有耐瘠薄、抗病虫害、适应性强、生长迅速等优点,特别是一些野生种叶片大、叶量多,更适合于刈割,这些优点使其成为一种很具有发展潜力的优质牧草资源。但目前荞麦的饲用价值仍未得到充分的发掘与利用。本文着重介绍了荞麦在我国的栽培、饲用历史和现状,结合荞麦饲用于猪、反刍动物及家禽等方面的研究进展,分析了荞麦在饲用化发展中将面临的问题,并对其应用前景进行了评价与展望。