肉鸡免疫抑制的诊断

许多因素看起来很像是免疫系统失调的征象,然而仍应对这些因素进行全面检查以便与其它真正由免疫抑制造成的近似和相同的临床表现相区别。为此目的,最好是同时结合进行现场诊断和实验室诊断。本文讨论肉鸡免疫抑制性病症的识别和诊断。     

实验性黄曲霉中毒的肉鸡发生免疫抑制

以0．3和1ppm的纯化黄曲霉毒素B1作肉鸡细胞免疫效应的研究，经喂0．3和1ppm黄曲霉素素B1的鸡，用醋酸α-萘酯酶反应检测其淋巴细胞数显著下降（P＜0．05），白蛋白和球蛋白量也显著下降（P＜0．05）。Pier等（1970）发现了黄曲霉毒素能抑制蛋白质的合成和抗体的产生。主要通过宿主迟发型过敏反应和组织移植排斥反应，以评价黄曲霉素素B1对细胞免疫的作用，尚未明确喂黄曲霉毒素B1的鸡的外周血液TI林巴细胞数，本研究测定了试验鸡的外周血液中经醋酸α-萘酯酶（ANAE）染色的T淋巴细胞的百分率。     

肉鸡免疫抑制综合征的诊治

<正>近2年来,在肉鸡养殖过程中出现了一种以免疫抑制为主的新病—免疫抑制综合征。本病主要发生在肉鸡上。由于本病给当前肉鸡生产造成了很大的损失,甚至使部分养殖户放弃养殖。对此,笔者将自己对本病的诊治经验介绍如下:1流行特点主要侵害20～35日龄的商品肉鸡,尤其是在免疫以后的4～6天     

浅析猪免疫抑制的防制

笔者在近些年的猪病诊治过程中经常遇到猪免疫抑制现象,导致了猪群免疫力和健康水平下降,对疾病的易感性增高,导致大批猪死亡或淘汰,给养猪生产带来很大的经济损失。     

家禽的免疫系统与免疫抑制

如我们所知，健康与疾病控制在商品家禽的生产管理中依然是优先关注的领域。饲养员和技术人员都花费了大量的时间来监测生产中鸡群的健康和生产性能。家禽饲养的许多方面（包括环境、遗传、免疫程序、预防和治疗药物、饲料添加剂、营养、卫生设施以及饲养场的生物安全）都影响着家禽的健康。     

肉鸡生产中的兽医卫生管理

1.鸡舍建设及位置——鸡舍简陋,规模过小,舍间密度过大,人鸡共栖,疾病不断 2.水源选择——院内或鸡舍内打井,浅层地表渗透水,大肠杆菌污染愈来愈重饮水标准:大肠杆菌103/升 3.冬季饲养,只保温,不通风,空气污浊,     

使肉鸡发挥最佳生产性能的措施

肉鸡生产企业的目标都是希望以尽可能最低的成本,获得最大的生产性能。这首先需要有优秀的品种。然而,由此带来的挑战是如何在所有影响因素之间找到平衡点。     

日粮添加铬制剂可减缓肉鸡免疫抑制

为研究在热应激(23.9~37℃)条件下,不同水平有机铬和无机铬(Cr)对肉鸡生产性能、免疫功能和血清无机物浓度的影响,韩国忠南国立大学的研究人员将1日龄150只肉雏鸡随机分为5个处理组,每个处理3个重     

鸡的免疫抑制及应对措施

20多年来,我国现代化畜牧业飞速发展,大群集约化、工厂化养鸡业技术也日趋完善。科学饲养中疫苗的免疫是其中非常重要的一个环节,但在免疫过程中往往会出现免疫抑制现象,使免疫效果较差或失败,给养殖场、户造成一定的经济损失。     

白羽肉鸡疾病流行特点与防治对策

禽病是导致我国家禽死亡、淘汰、生产性能下降的主要原因.现已成为制约我国养禽业健康发展的最重要因素.近几年来,我国因家禽发病死亡造成的直接经济损失年均超过100亿元;而间接经济损失的估算值则远超过100亿元;     

不同剂量环磷酰胺对肉仔鸡免疫抑制的影响

350只肉仔鸡随机分成5组,第1组为对照组,第2至5组为处理组。14日龄开始,对照组胸肌注射0.5ml的生理盐水,第2至5组分别按40、80、120、160mg/kg的剂量,同部位注射生理盐水稀释的环磷酰胺(CY)0.5ml,1次/d,连续注射3d。21、35、42、56日龄时每组随机抽取10只鸡进行屠宰取样,测定各组鸡的器官指数,另取3只鸡,测定脾脏淋巴细胞增殖转化。试验结果表明:一定剂量的环磷酰胺能显著降低肉仔鸡早期的体质量,且效果与注射剂量呈依赖关系,降低鸡早期脾脏指数和法氏囊指数,显著减少由ConA诱导的脾脏淋巴细胞增殖转化。     

用精益擦亮眼睛(1)——兼谈英惠尔公司的精益生产案例

<正>1概述经济全球化的迅猛发展与技术变革的日新月异,使全世界的经济环境发生了深刻变化,使当今的企业管理面临诸多挑战。由于市场经济的发展,买方市场上的企业竞争和全球市场一体化带来的国际竞争日益加重了企业应对市场变化     

用精益擦亮眼睛(2)——兼谈英惠尔公司的精益生产案例

<正>4英惠尔为何要推行精益生产?4.1学习型组织的内在驱动英惠尔成立近10年,经过艰苦探索与不懈努力,业务发展取得了长足进步,在国内饲料添加剂行业居于领先地位,并且已经摸索出了一整套行之有效的市场营销模式。根据公司长远发展     

Multilocus sequence typing of Campylobacter jejuni from broilers

Campylobacter jejuni isolates from a national Swedish Campylobacter monitoring in broilers were characterized by multilocus sequencing typing (MLST) in order to study the genetic diversity of this bacterial population. Isolates were initially characterized by pulsed-field gel electrophoresis (PFGE). One hundred were chosen for MLST genotyping. PFGE identified 69 distinct types compared to 44 different sequence types (STs) identified with MLST. Eighteen STs had not been described previously, while the remaining 26 STs were assigned to previously known clonal complexes. The majority of isolates were of genotypes noted in broilers and in humans in earlier studies. However, three clonal complexes, ST-206 complex, ST-677 complex and ST-1034 complex, previously associated with wild bird and environmental samples, were among the genotypes found. This study shows that most of the Swedish broiler isolates were of genotypes noted as common in broilers. However, it also highlights the potential influence of environmental sources on the broiler C. jejuni genotypes.     

通威风范:认真与清醒

通威集团经过18年的艰苦创业,取得了令人瞩目的成绩,已发展成为中国最大的水产饲料及重要的畜禽饲料生产企业。作为中国水产行业的领头羊,通威以其“认真与清醒”的独特品质和海纳百川的胸怀,不折不扣地展示着自己作为领头羊的王者风范,悄然而坚实地打造着自己的“水产王国”:建立水产科技园,在全国率先推出第一条品牌无公害鱼,建立了从苗种繁育、饲料生产、水产养殖、深加工等完整的产业链等。探寻通威集团发展的成功之路,我们不难发现:良好管理是企业发展的关键,追求一流的品质是企业核心所在,而完善的服务则能创造出更高的价值。1追求卓…     

Isolation of Campylobacter from circulating blood of commercial broilers

Campylobacter spp. are present in organs and tissues of broiler chickens but the dissemination route is unclear. The aim of the current study was to determine Campylobacter prevalence within circulating blood of commercial broilers. Broilers were acquired from 19 flocks originating from three commercial poultry processing companies. Using aseptic blood collection techniques, 5 ml of circulating blood was collected from each bird and the sample analyzed for Campylobacter. The Campylobacter colonization status of each bird was determined by aseptically sampling and analyzing the ceca. Campylobacter was recovered from 58% (11/19) of flocks sampled. From the 248 total birds sampled, 12% and 46% of the birds had Campylobacter in the blood and ceca, respectively. This study documents Campylobacter prevalence in the circulating blood of commercially raised broilers. Campylobacter presence in the circulatory system may indicate the path used by the organism for rapid dissemination to organs and tissues. From a processing viewpoint, Campylobacter presence in circulating blood of market-age broilers may increase the likelihood of cross-contamination between birds during slaughter.     

Virus-induced immunosuppression

Infection with a variety of viruses results in the suppression of the host's immune system. Several mechanisms thought to be responsible for this effect are discussed: infection and alteration of lymphocytes and macrophages, production of soluble suppressor factors, and the induction of suppressor cells. The clinical significance of virus-induced immunosuppression is also discussed.     

Antimicrobial resistance in Clostridium perfringens isolates from broilers in Belgium

The antimicrobial susceptibility of Clostridium perfringens strains isolated from Belgian broilers between May and September 2007 was investigated. All 39 tested isolates were sensitive to enrofloxacin, erythromycin, tylosin, florfenicol and bacitracin. Twenty-six (66%) and 24 (61%) out of the 39 tested isolates showed acquired resistance to tetracycline and lincomycin, respectively. The C. perfringens isolates were also screened by PCR for the presence of the resistance genes tet(K), tet(L), tet(M), tetB(P), tet(O), tet(W), lnu(A) and lnu(B). In 22/26 tetracycline resistant strains and 7/24 lincomycin resistant strains, resistance could be attributed to one or more of these genes. An extended frequency distribution range of MICs was seen for ampicillin. These data are consistent with data derived from studies carried out in 1980 and in 2004, indicating that no changes in antimicrobial resistance patterns have taken place during time in C. perfringens isolates from broilers in Belgium.