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我县蛋鸡饲养场几年来流行鸡马立克氏病,经我县畜牧兽医中心的调查研究,在江苏家禽研究所的指导下,从1999年春实施1日龄和36日龄二次皮下注射马立克氏病火鸡疱疹病毒疫苗防制蛋鸡马立克氏病,取得了非常满意的效果。现介绍如下:1基本情况该鸡场一直采用一免法防制鸡马立克氏病,蛋鸡雏多数售给养鸡户,多在80日龄-105日龄期间发病,其发病率及死亡率多在65%-80%之间,经病理剖检证实为内脏肿瘤型,无有效治疗方法。在1999年春夏实行加强免疫(二免)后,马立克氏病发病率大幅度下降,实践证明防制效果非常显著… 相似文献
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为了研究1日龄雏鸡同时免疫新流法三联疫苗与马立克氏病活疫苗对马立克氏病活疫苗免疫效果是否有干扰,试验将1日龄雏鸡分为5组,第1组商品蛋鸡不免疫,第2组SPF鸡不免疫,第3组商品蛋鸡仅免疫马立克氏病活疫苗,第4组商品蛋鸡同时接种新流法三联疫苗与马立克氏病活疫苗,第5组空白对照鸡不免疫,于雏鸡8日龄时对第1~4组用马立克氏病超强毒Md5株进行攻毒,攻毒后90 d内连续观察临床症状、剖检变化及病理组织学变化。结果表明:第1,2组鸡出现精神沉郁、肢体麻痹等临床症状并有部分鸡死亡,对死亡鸡只剖检可见,肝脏、脾脏肿大,全身器官出现肿瘤;对剖检鸡只进行组织病理学观察,可见典型的马立克肿瘤病变。而第3~5组鸡则无任何临床病症出现。说明无论是单独免疫马立克氏病活疫苗或是与新流法三联疫苗同时免疫,均能对鸡只提供良好保护,同时免疫新流法三联疫苗与马立克氏病活疫苗不会影响马立克氏病活疫苗的免疫效果。 相似文献
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用灭活马立克氏病病毒和火鸡疱疹病毒混合制备了一种双价疫苗。给不分性别的日龄白来航鸡接种,21日龄时用感染强毒马立克氏病病毒的家禽血液攻毒。分别与火鸡疱疹病毒和灭活马立克氏病病毒进行比较,研究了这种疫苗的效力。双价疫苗明显推迟由马立克氏病引起的死亡。按马立克病特异性死亡和病变发生的百分比判定诱发出最高的保护效力。双价疫苗接种鸡各器官的眼观淋巴肿瘤和淋巴组织增生病变的发生率、范围和严重程度均低于其他攻毒鸡。此外,双价疫苗接种鸡的病毒血症水平始终显著低于其他鸡。 相似文献
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2020年11月份,江西省宜春市某散养鸡场50日龄鸡出现消化不良、精神萎靡、死前倒地抽搐并呈"劈叉姿势"症状,部分病鸡体表存在明显肿瘤。为了对发病鸡所患疾病进行诊断,采用发病情况调查、剖检病变、病理组织学观察及PCR检测方法进行鉴定,同时对阳性条带测序比对,构建系统进化树。结果表明:剖检病死鸡可见心脏、肝脏、肾脏、肺脏有大量灰白色肿瘤灶,脾脏明显肿大。送检病料病理组织切片符合马立克氏病的病理特征;病原核酸检测显示马立克氏病病毒、禽白血病病毒和禽网状内皮组织增殖病病毒为阳性;阳性条带测序比对结果显示禽网状内皮组织增殖病病毒序列与马立克氏病流行毒株有高度相似性,为假阳性结果。说明该鸡场鸡群感染了马立克氏病病毒和禽白血病病毒,可采取改善养殖环境并结合疫苗免疫等方式科学防控,养鸡场应重视马立克氏病的实验室鉴别诊断和防控。 相似文献
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随着养禽业规模化发展,雏禽和成禽调入与调出不断,禽传染病日益复杂,尤其是以肿瘤为主的禽传染病包括鸡马立克氏病、禽白血病、网状内皮组织增殖症等病发病率相对增高,给养禽业造成了巨大威胁。现针对这三种病的诊治与分辨,笔者进行如下分析。一、马立克氏病马立克氏病是由马立克氏病毒引起的一种肿瘤性疾病。该病主要感染鸡。出雏和育雏室的早期感染可导致很高的发病率和死亡率。年龄 相似文献
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鸡三种肿瘤病在广西的流行病学研究 总被引:23,自引:3,他引:20
对采自广西20个鸡场106群鸡的360只病、死鸡共1126份组织样品进行检测,结果马立克氏病的群阳性率为84.91%,个性阳性率为73.33%,网状组织增生症的群阳性率为25.47%,个体阳性率为13.61%,禽白血病的群阳性率为16.98%,个体阳性率8.89%,肿瘤病二重及三重感染率为21.92%,在有肿瘤病变和无肿瘤病变的病例中,马立克氏病的阳性率分别为77.85%和47.17%,其中60日龄以上鸡的阳性检出率显著高于60日龄以下的鸡(P<0.05),对马立克氏病和网状组织增生症而言,腺胃是最理想的检测组织。 相似文献
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人和家畜会发生癌症,禽也不例外,马立克氏病就是鸡的一种癌症.患这种病的鸡,许多内脏器官长出由异常的淋巴细胞构成的肿瘤组织团块,以致器官肿大变形,组织受到破坏.早在1907年,匈牙利一位兽医科学工作者马立克首先报道本病,他见到病鸡跛行、瘫痪、翅膀下垂等症状,就称之为"鸡麻痹症".其后许多科学家对此病进行了研究,从不同的角度考虑,把它称为"多发性神经炎"、"鸡神经淋巴瘤"、"禽白血病综合征"等等.一病多名,造成许多混乱.后经兽医工作者建议,于1964年,在世界兽医家禽协会会议上讨论通过,把这种病统一命名为马立克氏病. 相似文献
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马立克氏病(MD)是由疱疹病毒B群马立克氏病病毒(MDV)所引起的一种肿瘤性传染病。近年来,由于病毒毒力的增强,其症状已由原来神经麻痹型为主渐变为内脏肿瘤型为主。本文统计了两批肉种鸡发生MD的临床病变数据,以期为免疫、病理及临床工作者提供参考依据。一、发病前情况见表1。表1鸡群发病前情况二、发病情况A群于106日龄首先出现一只典型神经麻痹型马立克氏病病鸡。随后,鸡群食欲减退,鸡只逐渐消瘦,舍内地面散落羽毛增加;B群相继发病,情况见表2。表2两群鸡发病情况自第一例MD病鸡出现后,即实施诊断跟踪检测。对死亡鸡只和疑为MD的鸡只… 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献
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乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制. 相似文献