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51.
A 5-year-old imported Zangersheide gelding was evaluated for SC swellings over both forelimbs and lameness localized to the distal metacarpus. Ultrasound examination of the SC masses was compatible with verminous granulomas. Linear hyperechoic foci were present within the suspensory ligament branches of both forelimbs, suggestive of ligamentous parasitic infiltrates. A diagnosis of onchocerciasis was confirmed on biopsy of a SC mass. The gelding was treated with ivermectin and a tapering course of PO dexamethasone but was eventually euthanized. Necropsy confirmed the presence of SC eosinophilic granulomas and degenerative suspensory ligament desmitis, both with intralesional nematodes. Given the location and appearance of the nematode, a diagnosis of Onchocerca sp., most likely O. reticulata, was made. Onchocerciasis should be included as a differential diagnosis for multifocal suspensory ligament desmitis with these sonographic characteristics when paired with SC masses in imported European Warmbloods.  相似文献   
52.
鸡传染性法氏囊病(IBD)是一种严重危害养禽业的高度致死性和免疫抑制性传染病。为研制IBD重组火鸡疱疹病毒(HVT)活载体疫苗,本研究构建了表达鸡传染性法氏囊病病毒(IBDV)保护性抗原VP2基因的重组HVT并对其体外生物学特性进行了分析。通过RT-PCR扩增IBDV超强毒株VP2基因并克隆入pCI载体,获得重组真核表达质粒pCI-VP2。用限制性内切酶将携带CMV启动子的VP2基因表达框架切下,连接于入门质粒pENTR,构建获得重组入门质粒pENTR-VP2。将pENTR-VP2与HVT重组黏粒H3-Kan/ccdB进行LR重组反应,构建重组表达黏粒H3-VP2。用H3-VP2与其他4个相互重叠并覆盖HVT全基因组的黏粒共同转染鸡胚成纤维细胞(CEF),拯救获得重组病毒rHVT-VP2。将重组病毒在CEF中连续传至20代后用PCR、间接免疫荧光试验和免疫印迹试验进行检测,并绘制重组病毒体外生长曲线,分析其体外复制特性。结果表明,重组病毒rHVT-VP2能够稳定表达VP2蛋白,rHVT-VP2在CEF中的复制能力与亲本病毒无明显差异。重组病毒rHVT-VP2免疫鸡后能够诱导产生IBDV中和抗体,并对IBDV强毒株攻击引起的死亡提供90%免疫保护。重组病毒rHVT-VP2的构建为研制IBD重组HVT活载体疫苗奠定了基础,对IBD的防控具有重要意义。  相似文献   
53.
【目的】研究N,O-羧甲基壳聚糖对鸡的急性毒性,评价该药的安全性;【方法】以最大浓度的N,O-羧甲基壳聚糖(10.5%),按20ml/(kg·bw)(2.1g/(kg·bw)/次)剂量24h内给鸡灌服;【结果】给药后连续观察7天,各组试验鸡全部存活,临床、剖检均未见到异常变化,测不出LD50,根据新药审批办法中关于急性毒性的要求,进行最大耐受量的测定。鸡灌服给予N,O-羧甲基壳聚糖的最大耐受量为10.5g/(kg·bw),相当于临床拟用量的3500倍;【结论】N,O-羧甲基壳聚糖毒副作用很小,临床可以安全应用。  相似文献   
54.
The commercial, welfare and environmental impacts of rearing small colonies of free-range chickens in newly planted woodland at two sites in the UK, during the first 2 years of the enterprise, were investigated. Newly planted rather than established trees were used so that commercially viable species could be planted in a way that would suit the management of the chicken enterprise, and small colonies were used so that farmers wishing to diversify could buy into the system progressively. It was anticipated that marketing a high specification product would provide an immediate income, whilst waiting for the future investment in trees to grow.  相似文献   
55.
本研究以胰岛素样生长因子Ⅰ(insulin-like growth factors-Ⅰ, IGF-Ⅰ)基因作为候选基因,运用PCR-RFLP法检测基因变异,并分析其变异与鸡末期产蛋性能的相关性。以绿壳蛋鸡(n=113)作为试验材料,对IGF-Ⅰ基因5'调控区进行遗传多样性研究。研究结果表明,该调控区扩增产物经PstⅠ酶切后出现AA、AB、BB共3种基因型,经χ2检验绿壳蛋鸡在IGF-Ⅰ位点上符合Hardy-Weinberg平衡状态(P>0.05)。相关分析表明,IGF-Ⅰ基因5'调控区PstⅠ位点对于产蛋末期(14和15月龄)的产蛋性能没有显著影响(P>0.05)。  相似文献   
56.
目的:观察芪参超微粉对雏鸡法氏囊疫苗免疫的影响。方法:将1日龄蛋公鸡360只随机均分为6组,21和35日龄,Ⅰ-Ⅴ组分别进行法氏囊疫苗首免和二免。14-21日龄,Ⅰ-Ⅲ组分别在基础日粮中添加1%、0.5%芪参超微粉和2%芪参散,Ⅳ组以玉屏风口服液饮水,V组为免疫对照组,Ⅵ组为不免疫空白对照组。试验前(14日龄,D0)及试验后第7(D7)、14(D14)、21(D21)、28(D28)、35(D35)、42(D42)天分别检测血清中IBD特异性抗体效价。试验后第7(D7)、21(D21)、35(D35)天检测外周血淋巴细胞增殖情况、血清中IL-2含量及体质量变化。结果:与免疫对照组相比,各用药组可以显著提高雏鸡法氏囊疫苗免疫效果,但各组间差异不显著。结论:芪参散经超微粉碎后使用较低剂量即可起到增强雏鸡免疫功能的作用。  相似文献   
57.
为探讨饲粮粗蛋白质水平对鲁西斗鸡肠道发育的影响,并建立肠道发育的生长模型,试验选用1日龄鲁西斗鸡雏鸡600只(公母各半),随机分为5个处理,每个处理6个重复,每个重复20只。试验分为0~6、7~12、13~18、19~24周4个阶段,采用单因子试验设计,各处理组分别饲喂不同蛋白质水平的饲粮。在6、12、18、24周末,每重复屠宰1只进行肠道指标的测定。结果表明:(1)饲粮粗蛋白质水平对6、12、18、24周末十二指肠、空肠及回肠长度和重量均无显著影响(P>0.05);(2)鲁西斗鸡十二指肠、空肠及回肠重量随周龄变化符合Logistic模型。  相似文献   
58.
夏业才  杨汉春 《中国家禽》2012,34(16):10-14
通过对鸡传染性支气管炎病毒(IBV)分离株SD060311和GD080122(肾型)的基因组进行RT-PCR扩增和基因序列测定,结果表明其基因组大小分别为27 788 nt和27 407 nt,与已报道的IBV全基因组序列大小不完全一致,但基因组编码基因的顺序与已报道的IBV一致,均为5′cap-Replicase-S-3a-3b-3c-M-5a-5b-N-poly (A)3 ′.与已报道的IBV毒株和火鸡冠状病毒进行比较,绘制系统进化树,结果显示,SD060311和GD080122(肾型)分离株自成一支,与中国分离株BJ株和A2株的亲缘关系最近.本研究不仅丰富了冠状病毒的生物信息数据库,且为进一步研究IBV致病机理和变异机制等奠定了基础.  相似文献   
59.
A study was conducted to determine the variations in physical characters and immunocompetence among scavenging local chicken ecotypes in Tanzania. Eighty-four adult scavenging local chickens from four eco-climatic regions of Tanzania were studied. Measurements of adult body weight, body length, shank length and egg weight and observations of plumage colour and pattern, earlobe colour, skin colour and the shape of the comb were conducted. The antibody response to sheep red blood cells, serum haemolytic complement and the cutaneous response to phytohaemagglutinin-P were assessed. Five ecotypes were identified and named Mbeya, Morogoro-medium, Ching'wekwe, Kuchi and Singamagazi. Singamagazi and Kuchi were significantly heavier, with longer shanks and heavier eggs than the other ecotypes. The average adult body weight for males ranged from 1621 g (Mbeya) to 2915 g (Singamagazi). Average female weights ranged from 1108 g (Morogoro-medium) to 2020 g (Singamagazi). Mean egg weights ranged from 37.65 g (Ching'wekwe) to 45.61 (Singamagazi). The Kuchi had mostly rose and walnut combs, while the other ecotypes were mostly single combed. In each ecotype there were chickens with a high or low antibody response to red blood cells, but there was a significant difference between the ecotypes.  相似文献   
60.
Rinderpest had been reported in most parts of Ethiopia when the Pan African Rinderpest Campaign (PARC) was launched. As a result of intensive disease investigation and strategic vaccination, most parts of the country are now considered provisionally free, and widespread vaccination has been replaced by clinical and serological surveillance. Details of any episodes of disease are recorded and followed up after laboratory confirmation of suspected cass using antigen-capture ELISA. This paper is based on observations on the performance of the antigen detection ELISA compared to the agar gel immunodiffusion (AGID) test, which also differentiates rinderpest from peste des petits ruminants (PPR). The stability of the specific viral antigen was monitored for 4 days, and rinderpest and PPR antigens were still detected, depending on the type of specimen. Antigen capture ELISA is more rapid, sensitive and virus specific than the AGID. Even if the cold chain of the specimen is compromised for a day or two during sample collection and submission, the specimen may still be suitable for testing by ELISA.  相似文献   
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