Performance of an enzyme-linked immunosorbent assay for the diagnosis of Brucella ovis infection in rams

AIM: To describe the performance characteristics (sensitivity and specificity) of an enzyme-linked immunosorbent assay (ELISA) for the diagnosis of Brucella ovis infection in rams. METHODS: Sera from a negative (n = 2535) and a positive (n = 589) reference population were tested in an ELISA for anti-B. ovis antibodies and cut-off values calculated from the raw, log10-transformed and fitted data. Statistical methods were used to fit curves to the frequency distribution of the data and receiver-operated characteristics analysis used to optimise the cut-off values. RESULTS: Analysis of the frequency distribution of the positive ELISA values suggested a normal distribution of the data, whereas, in the case of the negative population, a Pearson type IV curve appeared to best fit the data. The cut-off values calculated as the mean plus 1.96 standard deviations (s.d.) from the raw, log-transformed and fitted ELISA data did not differ markedly. The differences were much greater at the mean plus 3.09 s.d. cut-off, with the cut-off value calculated from the log-transformed data giving a much better estimate of specificity. Optimisation (minimisation of classification error) of the cut-off calculated from the fitted curves suggested varying cut-off values, depending on the prevalence of B. ovis infection. Discussion: Calculation of cut-off values from curves that were fitted from the observed data give more accurate estimations of the performance characteristics of an assay than traditional calculations from observed values. They also allow the calculation of optimal cut-off values taking into account the prevalence of B. ovis infection and give additional information about the performance of the assay at cut-off values varied according to the epidemiological situation.     

Performance and rideability issues in horses as a manifestation of pain: A review of differential diagnosis and diagnostic approach

Nonspecific performance and rideability issues are more likely a manifestation of pain in the ridden horse rather than a true behavioural problem. A systematic and thorough investigation focusing on the potential presence of pain-related conditions is thus crucial in horses with such complaints. It can, however, be challenging to determine whether the complaint is indeed related to pain, where the pain is located, and what the underlying cause is. This review describes the challenges of pain recognition in ridden horses and summarises the recently developed ridden horse ethograms that might enable pain to be assessed in an objective, valid and reliable way. Furthermore, the differential diagnosis and diagnostic approach to horses presenting potentially pain-related performance and rideability issues are discussed.     

Laboratory diagnosis

Diagnosis of internal parasitism is based on many factors, including clinical signs, case histories of individual animals and the herds of which they are a part, and, finally, specific laboratory findings. Laboratory methods used can be divided into those associated with the qualitative and quantitative examination of feces for parasite eggs, larvae, and oocysts, and laboratory findings on changes in physiologic status of individuals that may be produced by specific parasites.     

副猪嗜血杆菌病的实验室诊断

当养猪场出现特征性临床症状并在仔猪上观察到病理性损伤时(临床症状参照"临床和病理诊断"章节),应怀疑发生了副猪嗜血杆菌感染,此病的确诊必     

棉油致肉种鸡生产性能和繁殖性能下降的事故报告

2006年11月,河南省武陟县焦作禽业公司肉种鸡场种蛋孵化率急剧下降,半个月内由80．9％下降至最低18．1％,同时产蛋率也出现下降,由83．5％下降至最低的74．8％。经过现场调查、原因分析、化验检测和防治效果验证,确诊为饲用豆油中掺有大量棉油导致的结果,现将调查和防治情况汇报如下：     

The diagnosis and differential diagnosis of cataract in the dog

Cataract is a common eye condition in the dog, classified in several ways and with a varied aetiology. The clinical appearance of hereditary cataract is described in the Boston Terrier, Miniature Schnauzer, Staffordshire Bull Terrier, Cavalier King Charles Spaniel, Golden Retriever, Labrador Retriever, Large Munsterlander, English Cocker Spaniel, American Cocker Spaniel, Afghan Hound, Welsh Springer Spaniel, German Shepherd Dog, Standard Poodle. Cataracts secondary to other eye diseases, both hereditary and non-hereditary, and to systemic conditions are also discussed, as well as the differential diagnosis of cataract.     

The accuracy of intraoperative cytopathological diagnosis compared with conventional histopathological diagnosis

To determine the accuracy of intraoperative cytopathological diagnosis compared with conventional histopathological diagnosis, the authors obtained 100 specimens from masses of various organ systems chosen randomly from 65 dogs, 30 cats, and five exotic animals. Of the 100 specimens, a specific diagnosis was obtained in 42%, the correct pathological process (i.e., mesenchymal neoplasia, epithelial neoplasia, round cell neoplasia, or inflammation) was identified in 41%, in 1% the diagnosis was deferred, and in 16% an incorrect diagnosis was obtained. The overall accuracy rate of intraoperative cytopathological examination was 83%, which increased to 90% by the exclusion of splenic masses. The accuracy rate of diagnosing neoplasia was 87%, with a sensitivity of 89% and a specificity of 100%. Intraoperative cytopathological examination is an accurate diagnostic method with good sensitivity and specificity for the identification of neoplasia.     

枯草芽孢杆菌对脂多糖应激肉仔鸡生长性能、免疫性能和血清抗氧化性能的影响

本试验旨在研究枯草芽孢杆菌(BS)对脂多糖(LPS)应激肉仔鸡生长性能、免疫性能和血清抗氧化性能的影响。选用1日龄健康爱拔益加(AA)肉仔鸡192只(公母各占1/2),采用2×2两因子试验设计,2个因子分别为饲粮(饲喂基础饲粮或添加200 g/t BS的试验饲粮)和LPS应激(口腔灌服LPS溶液或生理盐水),随机分为：1)基础饲粮+生理盐水组;2)基础饲粮+LPS组;3)试验饲粮+生理盐水组;4)试验饲粮+LPS组,共计4个组,每组6个重复,每个重复8只鸡,试验期为28 d,分为3个阶段,包括应激前期(第1～14天)、LPS应激期(第15～21天)、恢复期(第22～28天)。结果表明：1)在第1～14天,饲粮中添加BS可显著提高肉仔鸡平均日增重(ADG)(P<0.05)。LPS应激显著降低第15～21天、第22～28天ADG(P<0.05),而饲粮中添加BS的肉仔鸡ADG显著高于未添加BS的肉仔鸡(P<0.05)。在第22～28天,饲粮中添加BS可显著降低饲料转化率(FCR)(P<0.05)。2)在第21和28天,LPS应激条件下,LPS应激显著提高脾脏指数(P...     

酸汤对断奶仔猪生长性能、免疫性能、抗氧化性能及肠道微生物区系的影响

本试验旨在研究酸汤对断奶仔猪生长性能、免疫性能、抗氧化性能及肠道微生物区系的影响。试验选用31日龄、体重[(5.34±0.86)kg]相近、健康的断奶仔猪45头,随机分为5组,每组3个重复,每个重复3头。试验Ⅰ组为对照组,饲喂基础饲粮,试验Ⅱ、Ⅲ、Ⅳ、Ⅴ组分别在基础饲粮的基础上添加0.5%、1.0%、1.5%、2.0%的酸汤。预试期7 d,正试期40 d。结果表明:试验Ⅱ、Ⅲ、Ⅳ、Ⅴ组的平均日增重(ADG)显著高于试验Ⅰ组(P<0.05);试验Ⅴ组的腹泻率显著低于试验Ⅱ、Ⅲ、Ⅳ组(P<0.05);试验Ⅴ组血清免疫球蛋白G(IgG)的含量为2.86 g/L,显著高于试验Ⅰ、Ⅱ、Ⅲ组(P<0.05);试验Ⅴ组血清超氧化物歧化酶(SOD)活性显著高于试验Ⅰ、Ⅱ、Ⅲ、Ⅳ组(P<0.05);试验Ⅳ组血清谷胱甘肽过氧化物酶(GSH-Px)活性显著高于其余各组(P<0.05);试验Ⅳ组血清丙二醛(MDA)含量显著低于试验Ⅰ、Ⅱ组(P<0.05)。试验Ⅴ组空肠绒隐比显著高于试验Ⅰ组(P<0.05);饲粮中添加酸汤有增加盲肠厚壁菌门相对丰度、降低拟杆菌门相对丰度的趋势,试验Ⅳ组盲肠乳杆菌属相对丰度显著高于试验Ⅰ组(P<0.05)。综上可知,饲粮中添加适量酸汤能提高断奶仔猪的生长性能、免疫性能以及抗氧化性能,一定程度上促进小肠形态发育以及改善盲肠菌群结构,可作为断奶仔猪饲料添加剂。     

杜蒙羊肉用性能活体检测及屠宰性能对比分析

[目的] 评价杜蒙羊的肉用性能、屠宰性能及肉品质。[方法] 选取60只杜蒙羊,公母各半,于5月龄时利用超声波背膘检测仪对羊只进行活体肉用性能检测,于6月龄时对羊只进行屠宰,测定主要屠宰性能指标以及肉品质和安全性评价指标;对杜蒙羊公羊和母羊的活体肉用性能指标、主要屠宰性能指标、肉品质和安全性评价指标进行统计学分析和比较。[结果] 杜蒙羊活体肉用性能指标检测结果表明,公羊的腰肌厚度和眼肌面积显著（P<0.05）大于母羊,背膘厚度与母羊差异不显著（P>0.05）;屠宰后肉用性能指标测定结果表明,公羊的背脂厚和眼肌面积显著（P<0.05）大于母羊。屠宰性能指标测定结果表明,杜蒙羊公羊的胴体重、净肉重、宰前活重均显著（P<0.05）高于母羊,公羊的屠宰率、胴体净肉率高于母羊,但无显著（P>0.05）差异;母羊的大腿骨重、小腿骨重、大腿骨长、小腿骨长均显著（P<0.05）低于公羊,公羊和母羊的4个骨指标两两之间呈正相关,大腿骨重和小腿骨重更接近线性相关。肉品质和安全性评价指标测定结果表明,杜蒙羊公羊的肌内脂肪含量显著（P<0.05）低于母羊;公羊的胴体肌肉水分含量与母羊差异不显著（P>0.05）;公羊和母羊肌肉中的铅、铬、汞、砷元素含量均符合《农产品安全质量 无公害畜禽肉安全要求》（GB 18406.3—2001）,母羊肌肉中的铬含量和汞含量显著（P<0.05）低于公羊。[结论] 杜蒙羊公羊的活体肉用性能和屠宰性能优于母羊,母羊的肉品质优于公羊。