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91.
Serial ultrasound examinations of the gravid uterus of a Jenny donkey (Equus asinus) carrying a transferred extraspecies horse (Equus caballus) conceptus between 11 and 33 days of gestation demonstrated that the embryo died before Day 33 even though the conceptus persisted in the uterus and the horse chorionic girdle invaded the maternal endometrium to form a circle of typically large horse endometrial cups in the right uterine horn. The high concentrations of horse CG secreted by these cups with its higher than usual ratio of FSH-like to LH-like biological activities of 1.4 compared to the 0.1 ratio of normal donkey CG hyper-stimulated the donkey’s ovaries to develop multiple large accessory follicles and resulting secondary corpora lutea which secreted high concentrations of progestagens that persisted in her bloodstream for the next 90 days. This case illustrated that, in all likelihood, girdle invasion can happen after the death of the embryo indicating autonomy of the chorionic girdle.  相似文献   
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93.
本研究旨在对广灵驴腺苷琥珀酸裂解酶(adenylosuccinatelyase,ADSL)基因进行克隆及生物信息学分析,并检测其在不同组织中的表达情况,为探究ADSL基因在广灵驴肌苷酸合成及风味形成中的作用机制提供理论参考。根据GenBank中公布的马(登录号:XM_001917207.5)、牛(登录号:NM_001102377.2)、猪(登录号:GU249574.1)等物种的ADSL基因mRNA序列,通过Primer Premier 3.0在线工具设计同源引物,RT-PCR法扩增并克隆ADSL基因序列,对编码序列进行结构与功能分析,最后用实时荧光定量PCR检测ADSL基因在广灵驴心脏、肝脏、脾脏、肺脏、肾脏、背最长肌组织中的表达水平。结果显示,广灵驴ADSL基因CDS长1 473 bp,编码490个氨基酸,提交至NCBI,登录号:MW037837,其核苷酸序列与马、牛、双峰驼、猪、绵羊、人、小鼠的相似性分别为99.5%、90.8%、92.3%、90.4%、90.7%、90.5%和86.0%。进化树分析结果表明,广灵驴与马的种属关系最近,与小鼠的亲缘关系最远。ADSL蛋白分子质量为55.44 ku,等电点为6.52,平均疏水指数为-0.243,是一种不稳定的酸性亲水蛋白。ADSL蛋白有41个磷酸化修饰位点,6个糖基化修饰位点,没有信号肽和跨膜结构,有1个卷曲螺旋。ADSL蛋白主要定位在细胞质,α-螺旋(68.98%)是主要的二级结构。ADSL基因在广灵驴6个组织中都有表达,其中肺脏中的表达量最高,显著高于其他组织(P<0.05),其次是心脏和肝脏,脾脏、肾脏和背最长肌中的表达量最低。本研究结果为今后探究ADSL基因在广灵驴肌苷酸合成及风味形成的分子机制奠定基础。  相似文献   
94.
REASON FOR PERFORMING STUDY: Dental disorders have recently been recognised as having major clinical and welfare implications in donkeys. However, no investigation appears to have examined the association of dental disorders with managemental factors and any intercurrent illness. OBJECTIVES: To determine the association of dental disorders observed in a post mortem study with age group, body condition score, time since last dental treatment, feeding and the illness that necessitated euthanasia or caused death. METHODS: A prospective study documented the type and prevalence of dental disorders in 349 mainly aged donkeys (median estimated age of 31 years) that were subjected to euthanasia over an 18 month period in 2005'Aì2006. The estimated age, body condition score, supplemental feed status, time since last dental treatment and nature of the intercurrent disease that necessitated euthanasia or caused death were also recorded. Multivariable analysis was performed to examine associations of these factors with specific dental disorders and between specific dental disorders. RESULTS: There was a high prevalence (93.4%) of significant dental disease. Age group was significantly associated with the presence of dental disorders and an older age range was a high risk factor for the presence of cheek teeth (CT) diastemata. There was a significant association between the presence of CT diastemata and the concurrent presence of displaced, missing and worn CT. There was also a significant association between the presence of diastemata and colic. CONCLUSIONS AND POTENTIAL RELEVANCE: Aged donkeys have a high prevalence of dental disorders especially of CT diastemata. Dental disorders and, in particular, the presence of CT diastemata were significantly associated with colic. Routine, prophylactic dental treatments should be performed, especially in aged donkeys.  相似文献   
95.
Cutaneous expression of behavioural processes remains unexplored in donkeys. This case report describes a case of traumatic alopecia in two donkeys secondary to mutual hair plucking behaviour. Two genetically unrelated, male castrated, 4-year-old Cotentin donkeys living together were presented for a 2-year history of alopecic, mainly nummular, nonpruritic lesions developing on the back, loin and croup. The general physical examination and behavioural assessment were unremarkable. Trichoscopy, scrapings and cytology were performed. Superficial bacterial infection was diagnosed but a 2-week course of antibacterial treatment showed no improvement. Histopathological examination showed features compatible with traumatic alopecia and consistent with several behavioural causes of alopecia resembling human trichotillomania or acute traction alopecia, canine traction alopecia, feline self-induced alopecia and murine barbering. Separation of the donkeys led to complete long-term remission. Clinical and histopathological findings in our case share lots of similar features with the different mechanical traumatic alopecic disorders mentioned above, making it impossible to simply classify the described affection. Whether alopecic lesions resulted from an exclusive behavioural process (either abnormal excessive mutual grooming or other social interactions) or were associated with underlying causes of pruritus is uncertain. Mechanical alopecia secondary to a behavioural process should therefore be suspected in cases of permanent patchy alopecic nummular lesions on donkeys living in groups.  相似文献   
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97.
本试验旨在研究饲粮粗蛋白质(CP)水平对断奶驴驹营养物质消化代谢及血清生化指标的影响。选取体况良好的5~6月龄公驴驹30匹,体重(88.21±5.79)kg,随机分为3组,每组10匹,分别饲喂消化能一致而CP水平分别为12.10%(Ⅰ组)、13.95%(Ⅱ组)和15.87%(Ⅲ组)的试验饲粮。试验期70 d,预试期10 d,正试期60 d;其中前31天为试验前期,后29天为试验后期。结果表明:1)Ⅰ组的粗脂肪(EE)和碳水化合物(CHO)的表观消化率有高于Ⅱ、Ⅲ组的趋势(P=0.083、P=0.077)。2)Ⅰ组的钙、磷摄入量极显著高于Ⅱ、Ⅲ组(P<0.01),Ⅲ组的粗纤维(CF)、酸性洗涤纤维(ADF)摄入量极显著高于Ⅰ、Ⅱ组(P<0.01)。Ⅰ、Ⅱ组的粪中磷含量显著高于Ⅲ组(P<0.05),Ⅲ组的粪中ADF含量显著高于Ⅰ组(P<0.05)。Ⅰ、Ⅱ组的尿中钙含量显著高于Ⅲ组(P<0.05),Ⅱ组的尿中磷含量显著高于Ⅰ、Ⅲ组(P<0.05)。3)Ⅲ组的食入氮极显著高于Ⅰ、Ⅱ组(P<0.01),Ⅲ组的粪氮和沉积氮显著高于Ⅰ、Ⅱ组(P<0.05),Ⅲ组的尿氮显著高于Ⅰ组(P<0.05),Ⅰ组的氮的生物学价值显著高于Ⅱ、Ⅲ组(P<0.05),Ⅲ组的尿能极显著高于Ⅰ、Ⅱ组(P<0.01)。4)试验前期,Ⅱ、Ⅲ组的血清总氨基酸含量显著高于Ⅰ组(P<0.05),Ⅰ组的血清免疫球蛋白M(IgM)含量显著高于Ⅱ组(P<0.05),Ⅲ组的血清补体3(C3)含量显著高于Ⅱ组(P<0.05)。试验后期,Ⅱ、Ⅲ组的血清总氨基酸含量显著高于Ⅰ组(P<0.05)。由此可见,饲粮CP水平的提高增加了CF、ADF摄入量及氮的摄入量、沉积量,提高了血清总氨基酸含量,降低了钙、磷的摄入量及EE、CHO的消化率和氮的生物学价值,同时降低了能量利用率,对钙、磷、CF、中性洗涤纤维(NDF)、ADF的消化代谢无影响。本试验条件下,驴驹饲粮的适宜CP水平为12.10%。  相似文献   
98.
[目的]调查山东省聊城市规模化驴场中马流感病毒的感染情况,并分析其可能的来源。[方法]从聊城的规模化驴场采集病料和血清,通过HI试验检测驴血清中的马流感病毒H3N8亚型抗体的阳性率。使用RT-PCR技术扩增肺脏和鼻腔棉拭子样品中的马流感病毒M基因,对获得的马流感病毒M基因与不同流感病毒的M基因进行序列比对,推测其来源。[结果]HI试验表明,120个血清样品中马流感病毒H3N8亚型血清抗体阳性率为33.3%(40/120);其中,母驴的马流感病毒H3N8亚型血清抗体阳性率为42.5%(17/40)、公驴为32.5%(13/40)、驴驹为25.0%(10/40)。通过RT-PCR检测发现,32.3%(21/65)的样品可测出目的条带。通过序列比对得出,该试验获得的流感病毒M基因与马属动物的H3N8亚型流感病毒高度同源(CY032222、CY032318、CY028821等),同源性最高可达99.8%。[结论]马流感病毒在聊城周边的数个规模化养驴场发生流行。该研究从驴体内分离的流感病毒M基因属于马流感病毒H3N8亚型M基因。  相似文献   
99.
本试验旨在研究长途运输应激对驴血液指标的影响。试验以12头体重(140.8±5.2)kg的德州驴为研究对象,运输距离约950km,发车地气温为-20℃,目的地气温为-10℃,历时21h,其中包括10次停车观察(≤20min)。分别在运输前、运输后0h和运输后3、5、7、9、15d采集颈静脉血15mL,进行血液激素指标、血常规指标和血液生化指标检测,并分别记录运输前、运输后0h和运输后10、20、30d体重。结果显示,与运输前相比,落地后0h血清中促肾上腺皮质激素(ACTH)、热休克蛋白90(HSP90)和皮质醇(cortisol)浓度均显著升高(P<0.05),落地后3、5、7、9、15d内逐渐降低,ACTH和HSP90基本恢复至运输前水平;中性粒细胞总数(Neu)、红细胞总数(RBC)和血红蛋白浓度(HGB)均较运输前显著上升(P<0.05),白细胞总数(WBC)有所上升但与运输前差异不显著(P>0.05),淋巴细胞总数(LYM)较运输前显著下降(P<0.05);血清总蛋白(TP)、血清白蛋白(ALB)、肌酐(CREA)、乳酸脱氢酶(LDH)、运输前后均未发生显著变化(P>0.05),谷草转氨酶(AST)、肌酸激酶(CK)、尿素(UREA)均较运输前显著上升(P<0.05);体重较运输前显著下降(P<0.05),运输后10d内体重已恢复至运输前水平。上述结果表明,长途运输可诱发驴的应激反应、肝脏损伤、机体代谢水平升高等,但免疫系统未受到明显损害,在落地后15d内机体逐渐从应激反应中恢复至运输前状态。  相似文献   
100.
驴的精液冷冻保存技术是在马的基础上逐渐发展起来的,特别在近十年来,有关研究明显增多,在诸多方面取得了积极的成果。文章主要以驴精液冷冻保存技术环节的发展为侧重点,就其研究成果进行了总结。  相似文献   
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