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排序方式: 共有598条查询结果,搜索用时 265 毫秒
161.
A. T. Mahne H. J. Marais L. M. Rubio‐Martinez J. H. Williams 《Equine Veterinary Education》2014,26(10):552-558
An 18‐year‐old Warmblood stallion was presented for an acute onset nonweightbearing right hindlimb lameness following a mild lameness of 2 weeks' duration. Severe swelling was present in the right femoral area. Despite extensive diagnostic procedures, no definitive diagnosis could be made. Packed red cell volume was persistently low. The horse improved with supportive treatment and was discharged at the owner's request. The horse presented 4 days later for bleeding from a previously made incision on the lateral femoral area. Due to deterioration of his condition, the stallion was subjected to euthanasia. Diagnosis of disseminated haemangiosarcoma, affecting primarily the hindlimb musculature and leading to pathological fracture of the femur was made at necropsy and subsequent histopathology. 相似文献
162.
Mahmoud G. El Sebaei Nagah Arafat Reham A. El-Shafei Mohamed A. El-Adl Amany Farag Abeer E. Aziza Abdelfattah H. Eladl 《Journal of animal physiology and animal nutrition》2021,105(1):129-139
This study was carried out to evaluate the effects of induced urolithiasis by high dietary calcium (Ca) or protein levels on biochemical analyte levels, redox status, selected inflammatory cytokines and histopathology in chickens. A total of 90 one-day-old white Hy-Line chicks were fed basal control diets containing 20% crude protein (CP) and 1% Ca until they reached 44 days of age. After that, the birds were divided into three groups (30 birds per group). All management factors (light, temperature, ventilation, stock density and diet) were identical among the three groups throughout the study except for the dietary Ca and protein percentages. Group I was fed a control diet containing 20% CP and 1% Ca, group II was fed a high-Ca diet containing 5% Ca, and group III was fed a high-protein diet containing 25% CP. Our findings clearly demonstrated that dietary imbalance (caused by high-Ca or high-CP levels) per se in chickens was physiologically harmful, as it was accompanied by post-mortem lesions; biochemical, redox status and histopathological alterations; and upregulation of inflammatory cytokines (interleukin (IL)-1β and IL-6). In particular, the birds fed the high-Ca diet clearly exhibited the most obvious alterations in most of the endpoints. In conclusion, this study constitutes the first extensive investigation of the effects of high-Ca or high-protein diets induced urolithiasis on growth performance, redox status, inflammatory cytokine levels and pathological characterization in chickens. 相似文献
163.
Philipe A. Leo Camila I. Amaral Willian H. M. Santos Matheus V. L. Moreira Leticia B. de Oliveira Erica A. Costa Mauricio Resende Raphael Wenceslau Roselene Ecco 《Journal of veterinary diagnostic investigation》2021,33(3):605
We investigated the occurrence and pathologic findings of transmissible viral proventriculitis (TVP) associated with the chicken proventricular necrosis virus (CPNV) in commercial broiler chickens in southeastern Brazil. Seventy-three broilers, 25–36 d old, with a history of reduced growth, were referred to our veterinary pathology services from 2013 to 2017. Broilers were clinically examined, weighed, and euthanized for postmortem examination. Broilers of different ages with proventricular histologic lesions were positive for CPNV by RT-PCR; however, the intensity of histologic lesions was higher among 33-d-old animals, and viral RNA detection was more frequent among those that were 28 d old. In the proventriculi of 35 of 73 (48%) broilers, lesions were characterized by glandular epithelial necrosis, lymphoplasmacytic and histiocytic infiltrates, and metaplasia of glandular epithelium to ductal epithelium. In 24 of 73 (36%) broilers with histologic TVP-compatible lesions, CPNV was detected by RT-PCR for the viral protein 1 (VP1) gene. Broilers with histologic lesions were lighter than expected compared to the Cobb 500 standard weight. TVP has not been reported previously in broiler chickens in Brazil, to our knowledge. 相似文献
164.
Akiko Sakuma Shizuka Sugawara Hikaru Hidaka Mitsuru Nakajo Yoshihito Suda Tomoyuki Shimazu Michael T. Rose Megumi Urakawa Tao Zhuang Guoqi Zhao Kouichi Watanabe Tomonori Nochi Haruki Kitazawa Kazuo Katoh Keiichi Suzuki Hisashi Aso 《Animal Science Journal》2020,91(1)
Mycoplasma pneumonia of swine (MPS) is caused by Mycoplasma hyopneumoniae (M.hp) and is a common chronic respiratory disease of pigs. Recently, a genetically selected variant of the Landrace pig (Miyagino L2) has a lower incidence of pulmonary MPS lesions. We investigated the pathological and immunological characteristics of MPS resistance in these pigs (n = 24) by comparing with the normal landrace pig (control: n = 24). The pathological MPS lung lesion score in MPS‐selected landrace pigs was significantly lower than in the control. The gene expression of interleukin (IL)‐12p40, which acts as a chemoattractant and a component of the bioactive cytokines IL‐12 and IL‐23, was significantly higher at the hilar lymph nodes, lung, and spleen in MPS‐selected landrace pigs than in control landrace pigs, and these were negatively correlated with the macroscopic MPS lung lesion score. In summary, we demonstrate that resistance against MPS in Miyagino L2 pigs is associated with IL‐12p40 up‐regulation, in comparison with normal landrace pigs without the MPS vaccine. In addition, a comparative study of macroscopic MPS lung lesions and IL‐12p40 gene expression in lung and hilar lymph nodes may lead to beneficial selection traits for the genetic selection for MPS resistance in pigs. 相似文献
165.
对黄瓜枯萎病抗病品种长春密刺、感病品种津研四号的幼苗伤根接种后根、根-茎、茎3个部位病菌生长及组织的变化进行了观察,结果表明品种间存在明显差异。病菌从伤口进入导管后菌丝向上扩展的速度在抗病品种中较感病品种中慢,原因可能在于导管分子类型不同;抗病品种的皮层薄壁细胞间隙未观察到菌丝,表明抗病品种能抵抗病菌通过表皮的入侵。两品种都观察到木质部导管中出现侵填体、壁的覆盖物、褐色物质及皮层薄壁细胞木栓化,但这些反应在抗病品种中出现较早,表明抗病品种较早形成保卫反应。 相似文献
166.
兔病毒性出血症弥漫性血管内凝血动态研究 总被引:1,自引:0,他引:1
对兔出血症的凝血象和组织病理学变化进行了动态研究。结果表明:兔出血症伴有弥漫性血管内凝血(DIC)病理过程,并呈动态发展规律。凝血象检测发现:感染后6h凝血酶原时间(PT)、白陶土部分凝血活酶时间(KPTT)缩短或正常,为高凝期,该期短,很快进入低凝期。感染后18hPT、KPTT显著延长,死前更明显。血小板数(PC)呈渐进性降低,纤维蛋白(原)降解产物(FDP)在感染后6h显著增加(P<0.01),感染后18h达高峰值。组织病理学观察表明:肺的病变严重而且有规律,感染后12h肺的微血栓检出率最高,同时在心、肝、肾、脑等器官也见微血栓。感染后24h或死兔的肺出血严重,血栓少见,表现为纤溶亢进的特征性变化。此外,患出血症的兔血管壁早期损伤明显,先于高凝期,可能是DIC的启动因素之一。 相似文献
167.
从养殖大菱鲆(Scophthalmus maximus)患病鱼体中分离出一种寄生性纤毛虫,通过活体观察、碳酸银法染色和扫描电镜对其形态学进行特征分析。经鉴定,该纤毛虫为蟹栖异阿脑虫(Mesanophrys carcini Groliere & Leglise,1977),隶属于寡膜纲、盾纤目、嗜污科、异阿脑虫属。患病鱼常表现为静伏池底,体色变暗,活力弱,摄食差,生长减慢,并发生急、慢性死亡。最明显的特征是病灶部位变白,略有浮肿,触摸柔软。流行病学特征显示,在大菱鲆的苗期、养成期、亲鱼培育期均可发生纤毛虫感染,幼鱼期发生率较高,发病水温14-20℃,盐度12~40。组织病理学观察分析表明,病灶组织处以盾纤虫为主要入侵微生物,常伴有细菌存在,但没有发现病毒性细胞病变和霉菌等其他寄生生物。 相似文献
168.
169.
170.
Since 1993, an epizootic viral disease has occurred in net-cage cultured red sea bream, Pagrus major (Temminck & Schlegel), in Peng-hu Island located on the south-western coast of Taiwan. The diseased fish exhibited abnormal swimming and were lethargic, but few visible external signs were observed. The cumulative mortality because of the disease sometimes reached 50-90% over 2 months. Histopathogical studies of the affected fish showed enlarged basophilic cells in the gill, kidney, heart, liver and spleen. These necrotic cells were Feulgen-positive and stained blue using Giemsa. Transmission electron microscopy revealed icosahedral virions in the cytoplasm of the necrotic cells. The viral particles consisted of a central nucleocapsid (75-80 nm) and envelope, and were 120-150 nm in diameter. These results suggest that the virus belongs to the Iridoviridae. Using polymerase chain reaction (PCR), approximately 570 bp fragments were produced from the viral DNA using as a template 1-F and 1-R primers derived from red seabream iridovirus (RSIV) from red sea bream in Japan. Similar results were also obtained using nested-PCR with different primer sets (1-F, 2-R and 2-F, 1-R). Although the size and some features of epizootics of this virus differed from RSIV in Japan, it shows close genetic affinities with the latter and it is suggested that RSIV has been introduced to Taiwan. 相似文献