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1.
鸡大肝大脾病(Big liver and spleen disease,BLS)是发生于商品代肉用产蛋母鸡的一种传染性疾病,1980年最先在澳大利亚发现,1988年Handlinger等对该病进行了描述.感染鸡直到性成熟后才出现临床症状,仅表现为精神沉郁、产蛋下降或达不到产蛋高峰.死亡率为1%.剖检患鸡或死亡鸡见肝脏、脾脏肿大,呈现腹膜炎和肠炎.  相似文献   

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国内信息     
产蛋期间鸭和鸡的肥胖基因台湾大学农学院畜产学系附设农业试验场沈添富、陈婉琳二先生对产蛋禽肥胖基因作了研究。他们萃取产蛋菜肉鸭和来航鸡各组织的总RNA ,用PCR引物针对菜鸭和来航鸡做反转录—聚合酶链锁反应 (RT PCR) ,以菜肉鸭、来航鸡的肝脏或脂肪组织的mRNA为模板 ,增  相似文献   

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日本名古屋大学农学部教授富田武宣布:1985年底利用假受精育种得到的鸡(白来航鸡)321只母鸡中22只(约7%)开始产红皮蛋。这项研究工作是由富田和爱知县综合农业试验场养鸡研究所研究组共同进行的。研究目的是将产红皮蛋的洛岛红鸡的基因导入产蛋率高的白来航鸡中、育成产红皮蛋的白来航鸡。该鸡种产蛋力强、蛋的价格也高(参阅本刊1986年4月7日号)。新育成的这种鸡开始产的红皮蛋是淡红色,与一般的红皮蛋的颜色不同。根据分析蛋壳  相似文献   

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目的:研究大孔吸附树脂纯化鸡枞皂苷的方法.方法:采用分光光度法测定鸡枞皂甙的含量,分别考察了树脂种类、样品液浓度、pH值、吸附流速、洗脱剂浓度对鸡枞皂甙分离纯化的影响.结果:HPD-450树脂最适合鸡枞皂苷的纯化.工艺条件为:洗脱剂乙醇的体积分数为40%,吸附流速为1~2mL/min,样品液浓度为2.5~4.0mg/mL,样品液pH值为5~7.采用HPD-450大孔吸附树脂对鸡枞皂甙进行纯化效果最优.结论:在上述条件下,大孔树脂可用于鸡枞皂甙的分离纯化.  相似文献   

5.
青海门源地区大(狂鸟)和雕鸮的食性比较   总被引:3,自引:0,他引:3  
1999~2002年的6~8月份,在青海门源地区收集了大(狂鸟)和雕鸮的吐弃块(pellets)和残留食物(food remains),带回实验室进行分检鉴定、研究分析.大(狂鸟)食物中共有736个猎物,其中高原鼢鼠28只、高原鼠兔139只、甘肃鼠兔142只、田鼠科动物422只、雀形目鸟类4只、香鼬1只;各猎物对大(狂鸟)食物的生物量贡献率分别为14.26%、40.79%、17.39%、26.99%、0.22%、0.35%.雕鸮食物中共有330个猎物,其中高原鼢鼠17只、高原鼠兔77只、甘肃鼠兔44只、田鼠科动物183只、雀形目鸟类2只、红脚鹬2只、高原兔5只;各猎物对雕鸮食物的生物量贡献率分别为11.83%、30.87%、7.36%、16.00%、0.15%、0.62%、33.17%.雕鸮的食物生态位宽度与大(狂鸟)的食物生态位宽度相近,食物生态位高度重叠,但是它们捕食同种猎物的比例显著不同.  相似文献   

6.
鸡传染性支气管炎病毒变异机制的研究进展   总被引:6,自引:0,他引:6  
鸡传染性支气管炎(Infectious bronchitis,IB),是由鸡传染性支气管炎病毒(Infectious bronchitis virus,IBV)引起鸡的一种急性、高度接触性传染病,可引起鸡呼吸道、输卵管、肾脏、肠道及腺胃等多部位病变.病鸡表现为咳嗽、喷嚏、发出气管啰音.幼鸡流鼻液,蛋鸡产蛋数量和质量下降,肉鸡食欲不振,肾型病鸡肾肿大、苍白,有大量尿酸盐沉积.鸡不分年龄、性别和品种均易感,但主要侵害1~4周龄的幼鸡[1].  相似文献   

7.
下丘脑和垂体调节母鸡的生殖生理和产蛋性能。为了解其产卵调控机制,利用RNA-seq技术对高产和低产庄河大骨鸡的下丘脑和垂体组织进行测序和分析,获得SNP/InDel位点,并进行数据统计及生物信息学分析,以鸡基因组作为参考,对SNP所在基因进行GO富集分析。结果显示:SNP/InDel纯合子变异体数量高于杂合子变异体数量,垂体组织中的SNP/InDel数量高于下丘脑组织;SNP类型转换种类少于颠换,但转换类型的数量却远远高于颠换;垂体组织中的SNP所在基因的GO富集程度与生产性能呈负相关关系(P0.05),下丘脑组织中的SNP所在基因的GO富集程度与生产性能呈正相关关系(P0.05)。研究结果为大骨鸡的选育以及改善其生产性能的研究提供了理论依据。  相似文献   

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目的:探讨促卵泡素(FSH)对低产期肉用种母鸡在产蛋数量和孵化的影响,寻求较佳的用于提高低产期母鸡产蛋的激素剂量。方法:本试验采用同种激素不同剂量的处理方式,比较实验组和对照组产蛋量和孵化情况。结果:注射不同剂量的激素对鸡的产蛋有一定的影响,实验组一的平均产蛋数与对照组接近,其它四组均显著低于对照组(P<0.05),孵化率与健雏率与对照组无显著差异(P>0.05)。结论:小剂量激素处理对鸡产蛋量没有太大的影响,但大剂量会引起鸡生殖系统萎缩,激素处理对受精卵孵化及雏鸡生长并无负面影响。  相似文献   

9.
目的:探讨促卵泡素(FSH)对低产期肉用种母鸡在产蛋数量和孵化的影响,寻求较佳的用于提高低产期母鸡产蛋的激素剂量。方法:本试验采用同种激素不同剂量的处理方式,比较实验组和对照组产蛋量和孵化情况。结果:注射不同剂量的激素对鸡的产蛋有一定的影响,实验组一的平均产蛋数与对照组接近,其它四组均显著低于对照组(P〈0.05),孵化率与健雏率与对照组无显著差异(P〉0.05)。结论:小荆量激素处理对鸡产蛋量没有太大的影响,但大剂量会引起鸡生殖系统萎缩,激素处理对受精卵孵化及雏鸡生长并无负面影响。  相似文献   

10.
江淮棉区棉大卷叶螟主要寄生性天敌的寄生作用   总被引:2,自引:0,他引:2  
通过大田调查与室内饲养观察结果表明,江淮棉区棉大卷叶螟Sylepta derogataFabricius的主要寄生蜂(蝇)有7种:卷叶螟绒茧蜂Apanteles derogatae(Watanabe)、叶卷蚁形蜂Goniozus japonicus(Ashmead)、卷叶螟姬小蜂Sympiesissp.、菲岛扁股小蜂Elasmus philippinensis(Ashmead)、广黑点瘤姬蜂Xanthopimplapunctata(Fabricius)、广大腿小蜂Brachymeria lasus(Walker)和玉米螟厉寄蝇Lydella grisescens(Robineau-Desvoidy)。其中,卷叶螟绒茧蜂和卷叶螟姬小蜂为棉大卷叶螟幼虫期优势寄生蜂种,广大腿小蜂为幼虫-蛹跨期优势寄生性天敌。自然情况下,棉大卷叶螟的被寄生率高达25.7%,寄生性天敌对棉大卷叶螟种群起着重要的控制作用。  相似文献   

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K. Hausmann 《Protoplasma》1979,100(2):199-213
Summary The membranes of the pellicle of the ciliatePseudomicrothorax dubius are investigated using thin section electron microscopy and freeze-fracture replicas. The plasma membrane is covered by a surface coat and is connected to the outer alveolar membrane by short, sometimes branched, bridges. The inner alveolar membrane is coated on both sides. The epiplasm lies in intimate contact with the cytoplasmic surface of this membrane, and there is a corresponding deposit on the other surface. This deposit is regularly striated.The epiplasmic layer and the alveoli are interrupted at sites of cytotic activity,e.g., the attachment sites of trichocysts, the cytoproct, and the parasomal sacs. The striated deposit ends where the epiplasm ends, indicating a direct relationship between these two epimembranous layers.There is a deposit along the sides of the first part of the tip of the trichocysts, and in this region the trichocyst membrane is free of intramembranous particles.The membrane of the parasomal sacs has a coat on both surfaces. That on the extraplasmic surface is similar to the surface coat of the plasma membrane. The origin of the cytoplasmic coat is unknown. The cytotic activity of these sacs is indicated by their highly irregular profiles.  相似文献   

13.
Summary The differentiation of the spermatid, especially in reference to the formation of the flagellum, and transformation of the shape of the nucleus was investigated in the domestic fowl.In the early stage of the spermatid, a prominent Golgi apparatus appears around the centrioles. The Golgi vesicles then surround the axial-filament complex which develops from the distal centriole. These vesicles fuse to form continuous membrane at the earliest stage of flagellar formation, and in the succeeding stage Golgi lamellae are attached to the plasma membrane of the developing flagellum. From these observations, it is assumed that Golgi apparatus may be a source of the membrane system of the flagellum.The microtubules distributed around the nucleus form the circular manchette. The anterior region of the nucleus with the manchette is cylindrical in shape and the posterior region without it remains irregular in shape. When the circular manchette has been completed, the whole nucleus acquires a slender cylindrical shape. The circular manchette then changes into the longitudinal manchette. The nuclei of spermatids without a longitudinal manchette are abnormal in shape. In view of these observations it is assumed that the nuclear shaping of the spermatid may be accomplished by circular manchette and the maintenance of shape of the elongated nucleus by longitudinal manchette.The authors wish to thank Mr. Takayuki Mori for his helpful suggestions and technical advices  相似文献   

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This study aimed to analyze the aqueous humor (AH) and the vitreous body (VB) of the eye of the adult frog Rana temporaria L. as a representative species of amphibians, which lead a semi-terrestrial life. The presence of collagen, albumin, uric acid and electron donors was shown in both media; however, there are slight differences in their concentrations. To determine collagen, a spectral-fluorescent probe, cyanine dye, was used. The presence of collagen in AH of the frog was found at the first time. The total content of electron donors (ascorbic and uric acids, tryptophan, and tyrosine) in VB and HA was roughly estimated at ~ 1.5 × 10− 4 mol/L. Both VB and AH absorb light in similar UV regions. The total protein and albumin contents in AH were found to be somewhat higher than those in VB. The uric acid content was at an equally low level in both intraocular media. It is supposed that the similarity of VB and AH compositions shown in this work is due to some exchange between VB and AH contents in the course of accommodation. The role of intraocular fluids in physiological functions of the eye and in protecting the retina against UV light is discussed.  相似文献   

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Summary The choriocapillaris is a fenestrated capillary bed located posterior to the retinal pigment epithelium. It serves as the main source of supply to the photoreceptors, retinal pigment epithelium, and other cells of the outer retina. The permeability of these capillaries to intravenously injected ferritin (MW — approx. 480,000; mol. diam. 11 nm) was examined in the mouse, rabbit, and guinea pig, each of which is characterized by a different type of retinal vascularization. In all three species, the bulk of the ferritin remained in the capillary lumina, where it appeared to be blocked at the level of the diaphragmed fenestrae. Some ferritin was present in endothelial cell vacuoles. The results confirm previous work on the rat choriocapillaris and indicate that the barrier function of the choriocapillary endothelium is present even among species in which the retinal circulation differs significantly.Supported by NIH grant EY03418  相似文献   

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