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91.
Concurrent infection with bovine leukaemia virus (BLV) and Theileria annulata was diagnosed in a Friesian calf about 6 months of age at a dairy farm at the Qassim region of central Saudi Arabia. The disease ended fatally with signs of liver and heart failure. There was anorexia, pyrexia, anaemia, generalized oedema and jaundice. Haematology showed low RBC counts, PCV percentage and haemoglobin concentration and WBC counts. Lymphocyte differential was high. Examination of blood smears stained with Giemsa’s stain showed the presence of piroplasms in red blood cells. Autopsy showed enlarged lymph nodes and lymphosarcoma lesions in the omentum and the heart. There was hydroperitoneum, hydropericardium and hydrothorax. The liver was pale yellow and friable. Impression smears from sliced lymph nodes and stained with Giemsa’s stain showed presence of Koch’s blue bodies in lymphoblasts. Histopathological examination revealed fatty degeneration of hepatocytes and pleomorphic lymphoblasts and giant cells in lymph nodes. Lymphoblasts infiltrated the omentum and heart tissues. Amyloid was found around blood vessels in the liver, kidneys and lymph nodes. BVL infection was diagnosed by demonstrating antibodies against the virus in serum using agar gel immunodiffusion and was confirmed with ELISA.  相似文献   
92.
93.
番鸭花肝的是近年流行的一种新的番鸭疫病,其特征性病变是死亡番鸭的肝、脾、小肠等部位出现灰白色的坏死点,本文自广东省主要疫区分离到几株病毒,这些病毒在番鸭胚上可继代繁殖,其胚液可使番鸭妇病。不同途径感染试验表明该病毒通过肌肉注射、爪垫部注射、口服,同居感染均可使番鸭发病和死亡,并具有典型病变,分离毒不能使半番鸭,本地鸭,鸡发病。  相似文献   
94.
Oral lufenuron is reportedly an effective treatment for some cats with dermatophytosis. The purpose of this study was to determine if lufenuron, when used as a pre-treatment prior to challenge exposure, would be protective against the development of infection after the direct topical application of fungal macrocondia (Microsporum canis spores). Three groups (n = 6/group) of juvenile cats were treated with either monthly oral lufenuron (30 or 133 mg/kg) or placebo. After 2 months of treatment, kittens were challenged using 10(5)Microsporum canis spores applied to the skin under occlusion. Cats were examined weekly and the following data collected: Wood's lamp examination; scoring for scale/crust, erythema and induration; lesion size; and the development of satellite lesions. Fungal cultures were performed bi-weekly. All cats became infected; the infections progressed, and then regressed, in a similar fashion in all groups. There were no consistent statistically significant differences in weekly infection scores between treated and untreated cats throughout the study. Treated cats did not recover faster than untreated cats. We conclude that oral lufenuron at the dosing schedule and conditions used in this study did not prevent dermatophytosis or alter the course of infection by direct topical challenge.  相似文献   
95.
The objective of this study was to evaluate of the growth performance, serum biochemical indices, liver antioxidant parameters and ability of anti-infection with Aeromonas hydrophila by adding the fermented Chinese medicine by Bacillus Subtilis to the carp fish feed, and to find out the appropriate supplemental level of fermented Chinese medicine in diets. Carp fingerling with an initial body weight of (35±0.5) g were set up to 6 experimental diets supplemented with 0 (control group), 0.1‰, 0.5‰, 1‰, 2‰ and 3‰ fermented Chinese medicine for 56 days, respectively. Each group had 30 fish and set up 3 repetitions. After the feeding trail,the fish were challenged with Aeromonas hydrophila to calculate the relative percentage survival (RPS).The results showed as follows:Supplementing fermented traditional Chinese medicine by Bacillus subtilis, the weight gain rate (WGR), specific growth rate (SGR), condition factor (CF), the activities of lysozyme (LSZ), complement 3 (C3),total protein (TP),total anti-oxidation capacity (T-AOC),total superoxide dismutase (T-SOD) and catalase (CAT) in serum of common carp were enhanced at different degrees, while the feed coefficient (FCR)and malondialdehyde (MDA) in serum were declined at different degrees.When the fermented Chinese medicine supplemental levels were 2‰ and 3‰,the effects were significant (P<0.05)(except for C3, ALP and Cr).The experimental results of the virulence of common carp infected with pathogen Aeromonas hydrophila showed that,the fermented herbal could obviously improve the ability of anti-infection, the immune protective rate of the group with 2‰, 3‰ doses of the fermented Chinese medicine could reach 77.23% and 74.63%, respectively. From what had been discussed above, the group with 2‰ and 3‰ doses of the fermented Chinese medicine had significant effect on the growth performance, serum biochemical indices, liver antioxidant parameters and Aeromonas hydrophila anti-infection ability. Considering the cost of adding fermented Chinese medicine, the recommendations for the best additive quantity was 2‰.  相似文献   
96.
为初步了解水貂隐孢子虫病的流行情况,作者于2005年11月份用饱和蔗糖溶液漂浮法检查了河北省肃宁县某水貂养殖场的469份粪便样品。结果,8份粪便样品为隐孢子虫阳性,总感染率为1.71%(8/469)。其中,白貂感染率为2.15%(5/233)、灰貂感染率为2.08%(1/48)、黑貂感染率为1.06%(2/188)。所查的8份隐孢子虫阳性样品均来自5~6月龄的水貂,表明幼龄水貂容易感染隐孢子虫病而老龄水貂不易感染。另外,8份阳性样品多数来自雄性水貂,显示水貂的隐孢子虫感染可能存在性别的差异性。根据卵囊形态和大小将水貂隐孢子虫初步鉴定为小球隐孢子虫(Cryptosporidium parvum)。同时,利用所收集的隐孢子虫卵囊进行了小白鼠感染试验,结果表明水貂源隐孢子虫不感染免疫抑制状态下的昆明系小白鼠。  相似文献   
97.
山东规模化养殖场毛皮动物多重感染病原学分析   总被引:2,自引:0,他引:2  
2012—2013年间,山东10个地市多家毛皮动物养殖场养殖的毛皮动物(狐狸、貉子、水貂)出现腹泻,皮肤湿疹,神经症状,空怀、流产、出血性肺炎等症状和病变类似的疫情,为探明其病因,本研究对发病规模化毛皮动物养殖场发病情况进行调查,并对送检的病料进行病原学检查,结果发现,犬瘟热病毒、细小病毒、阿留申病毒感染率分别为54.21%、47.30%、31.35%;肺炎克雷伯菌、奇异变形杆菌、肺炎双球菌、大肠杆菌、沙门杆菌、绿脓杆菌、加德纳菌的感染率分别为37.58%、25.05%、21.81%、14.04%、12.53%、10.37%、8.21%;犬瘟热病毒、细小病毒、阿留申病毒、肺炎克雷伯菌、奇异变形杆菌、肺炎双球菌6种病原的单独感染、二重感染、三重感染、四重感染分别为22.03%、39.52%、36.07%、2.38%,未见五重以上的感染。结果表明,近两年造成山东规模化场毛皮动物发病主要原因是由犬瘟热病毒、细小病毒、阿留申病毒与肺炎克雷伯菌、奇异变形杆菌、肺炎双球菌多重感染所致,这为规模化毛皮动物养殖场有效地控制疫病提供了理论依据。  相似文献   
98.
猪链球菌2型四川分离株猪体回归试验   总被引:5,自引:3,他引:5  
选用35~38日龄的健康断奶仔猪21头,分3组,用2005四川分离株SSsc0501分别经静脉、肌肉注射和口服3种途径感染,进行猪体回归试验。肌肉注射组(含菌0.6×108个/mL)16 h开始出现症状,至36 h全部死亡,发病率、病死率均为100%;静脉注射组(含菌0.2×108个/mL)25 h开始出现症状,48 h内全部死亡,发病率和病死率均为100%;口服攻毒组(含菌2×108个/mL)90 h后开始有发病症状,第9天有1头死亡,发病率75%,病死率33%。从感染病死猪的肝脏、脾脏、肾脏、心血、大脑、脑脊液、淋巴结、肺脏和关节液中均分离到链球菌,经鉴定为试验攻毒的目的菌,表明猪体能够很好地用于猪链球菌2型动物感染模型,同时说明该菌侵害器官广泛,为进一步探讨该病的综合防制提供了重要技术依据。  相似文献   
99.
影响马立克氏病毒感染的因素及疫苗免疫策略   总被引:1,自引:0,他引:1  
马立克氏病毒是高度细胞结合性、嗜淋巴组织的α疱疹病毒,其致病过程包括淋巴细胞的溶细胞感染和潜伏感染以及易感鸡体内CD 4 T细胞的致瘤性转化。宿主的遗传抗性、细胞免疫、体液免疫以及相关细胞因子和淋巴细胞等对M DV的感染过程有重要影响。针对M D肿瘤抗原的靶向免疫应答的保护性抗原分子和宿主细胞因子疫苗是今后疫苗研究的方向。  相似文献   
100.
We examined exogenous and endogenous development of Eimeria procera in experimentally infected grey partridges (Perdix perdix). Our examination included data on morphology, localization, duration of schizogony and gametogony and morphology of sporulated oocysts. The endogenous stages of E. procera developed in large numbers within the epithelial cells of caecal crypts. The asexual development comprised three generations of schizonts. The first fully developed macrogametes and microgamonts were observed on Day 5 post-infection (p.i.) in histologic section. The patent period began on Day 6 p.i. and ended on Day 11 p.i. with peak production of oocysts on Days 7 and 8. Long oval oocysts of E. procera measured 25.78–28.13 μm in length and 14.06–15.24 μm in width, sporulation time ranged from 18 to 24 h at 25°C and from 36 to 48 h at 20°C.  相似文献   
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