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21.
The accuracy of clinical observations was estimated using Bayesian latent-class models with two or more independent tests. Four veterinarians carried out systematic independent clinical examinations on 155 pigs in three herds. Based on the results of binary recordings of clinical observations on dullness, poor body condition (PBC), skin lesions, lameness, respiratory disease, and diarrhea, a latent disease state for each clinical disease was estimated using Gibbs sampling.

The accuracy of the clinical observations differed for the four observers and for different clinical signs. Population parameters were estimated from a Bayesian hierarchical model, and the accuracy of a random observer was calculated. We concluded that the accuracy of the veterinarians in this study substantiated the need to pursue more-precise definitions of the clinical findings and that larger sample sizes would be needed to provide reasonable variance estimates. Finally, we concluded that the uncertainty in the clinical decision-making process (starting with the clinical examination) needs to be represented fully.  相似文献   

22.
Genotyping of bovine leucocyte antigen DRB3.2 (BoLA-DRB3.2) in a total of 523 Norwegian Red (NR) cows from two groups selected for high protein yield and low clinical mastitis, respectively, identified 27 previously reported BoLA-DRB3.2 alleles across the groups. Significant differences in BoLA-DRB3.2 allele frequencies were found between the selection groups. Alleles *13, *18, *22 and *27 had a significantly higher frequency in cows selected for low clinical mastitis, while alleles *3, *9, *11 and *26 had a higher frequency in cows selected for high protein yield. Associations between BoLA-DRB3.2 alleles and clinical mastitis were analysed based on mastitis data from 741,072 first-lactation NR cows, of which 452 were genotyped. Alleles *22 and *26 were found to be associated with increased clinical mastitis, while alleles *7, *11, *18 and *24 had a favourable effect on mastitis resistance. Contradictory results from different studies investigating associations between BoLA-DRB3.2 alleles and mastitis indicate that future studies should focus on associations of mastitis with BoLA haplotypes rather than with single BoLA genes.  相似文献   
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Objective: To provide evidence that naturally occurring sepsis in dogs provides a unique opportunity to test new therapies in clinically relevant settings. Data sources: Human and veterinary literature. Human data synthesis: Sepsis is a devastating condition responsible for most intensive care unit deaths. Most clinical trials targeting inflammatory mediators of sepsis have failed to improve outcome in clinical patients despite promising results in laboratory animal models. Animal models of sepsis fail to reproduce the clinical syndrome and therefore lead to conclusions that may not be relevant to clinical care. Veterinary data synthesis: Sepsis is recognized but not well‐characterized in companion animal species. Despite some species variability, the cardiopulmonary response to sepsis in dogs is similar to humans. Additionally, inflammatory and coagulation changes that accompany canine sepsis are consistent with those documented in humans. Sepsis secondary to canine parvoviral infection offers the advantages of relative population homogeneity, predictable course, and easy early diagnosis. The disadvantages of canine parvovirus are that it affects a predominantly young and healthy population and results in low mortality with aggressive supportive care. Septic peritonitis and pneumonia have high mortality but can be challenging to diagnose, have a variable course, and affect a heterogeneous population, which can be an advantage or a disadvantage. Conclusions: Similar to trials currently being performed in canine cancer patients, veterinary clinical trials of new sepsis therapeutics may provide a unique opportunity to advance the treatment of sepsis in dogs, humans, and other species. Spontaneous sepsis from canine parvovirus, peritonitis, and pneumonia are common clinical conditions in which therapeutics can be tested.  相似文献   
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Robust threshold models with multivariate Student's t or multivariate Slash link functions were employed to infer genetic parameters of clinical mastitis at different stages of lactation, with each cow defining a cluster of records. The robust fits were compared with that from a multivariate probit model via a pseudo‐Bayes factor and an analysis of residuals. Clinical mastitis records on 36 178 first‐lactation Norwegian Red cows from 5286 herds, daughters of 245 sires, were analysed. The opportunity for infection interval, going from 30 days pre‐calving to 300 days postpartum, was divided into four periods: (i) ?30 to 0 days pre‐calving; (ii) 1–30 days; (iii) 31–120 days; and (iv) 121–300 days of lactation. Within each period, absence or presence of clinical mastitis was scored as 0 or 1 respectively. Markov chain Monte Carlo methods were used to draw samples from posterior distributions of interest. Pseudo‐Bayes factors strongly favoured the multivariate Slash and Student's t models over the probit model. The posterior mean of the degrees of freedom parameter for the Slash model was 2.2, indicating heavy tails of the liability distribution. The posterior mean of the degrees of freedom for the Student's t model was 8.5, also pointing away from a normal liability for clinical mastitis. A residual was the observed phenotype (0 or 1) minus the posterior mean of the probability of mastitis. The Slash and Student's t models tended to have smaller residuals than the probit model in cows that contracted mastitis. Heritability of liability to clinical mastitis was 0.13–0.14 before calving, and ranged from 0.05 to 0.08 after calving in the robust models. Genetic correlations were between 0.50 and 0.73, suggesting that clinical mastitis resistance is not the same trait across periods, corroborating earlier findings with probit models.  相似文献   
25.
目前临床上常用的免疫抑制药物如激素、环磷酰胺、环孢菌素等的毒副作用较大,且不能从根本上控制疾病的发生和发展,而中药免疫抑制剂应用免疫耐受机理,具有毒副作用小、疗效好等特点,故广泛应用于临床。作者对近年来有关中药免疫抑制作用的基础研究及临床作用作一综述,就其研究过程中存在的不足及发展趋势提出自己的见解,为今后中药免疫抑制剂的研究开发提供参考。  相似文献   
26.
A review is given about pathogenetic and clinical aspects of the well-known as well as of recently detected members of the family Coronaviridae. Special attention is paid to coronavirus infections of domestic cattle and pets, whereas avian, murine, rat and human coronaviruses are summarized briefly.  相似文献   
27.
猫下泌尿道综合征(FLUTD)是猫最常见的疾病之一,因其发病率高、病因复杂、确诊困难、治疗后易复发等特点,逐渐成为猫科疾病的研究热点。FLUTD包括多种疾病类型,精准治疗、合理预防已成为科学防控该疾病的关键。本文从FLUTD的分类、流行病学及风险因子、发病机制、临床症状、诊断和防治对该综合征进行综述,以推动猫下泌尿道综合征的深入研究及临床诊疗的发展。  相似文献   
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【目的】 研究连花柴芩可溶性粉对风热犯肺所导致的鸡发热、咳嗽、食欲减退、口渴喜饮等证候的临床疗效。【方法】 采用鸡传染性支气管炎病毒人工攻毒建立风热犯肺证肉鸡病例模型,将出现典型风热犯肺证临床症状的150只鸡纳入到试验中,并随机分为5组,30只/组,分别为连花柴芩可溶性粉高、中、低剂量组(连花柴芩可溶性粉浓度分别为4、2、1 g/L),麻杏石甘颗粒药物对照组(1 g/L),模型对照组,另设30只为健康对照组。除健康对照组和模型对照组外,各试验组连续饮水给药5 d,记录给药前后鸡的精神状态、体温、呼吸道症状、采食及饮水的变化,并检测各组鸡的免疫器官指数、外周血免疫细胞亚群指标,综合考察连花柴芩可溶性粉的临床疗效。【结果】 连花柴芩可溶性粉高、中剂量组对风热犯肺所致的鸡发热、咳嗽的总有效率分别为90.00%和86.66%,显著高于模型对照组(P<0.05),且对病鸡采食量下降、饮水量增多具有较好的缓解效果(P<0.05);连花柴芩可溶性粉能提高病鸡免疫器官指数,促进病鸡外周血中CD3+、CD4+、CD8+ T淋巴细胞增殖,且连花柴芩可溶性粉高、中剂量显著高于模型对照组(P<0.05)。【结论】 连花柴芩可溶性粉对风热犯肺所致的鸡发热、咳嗽、食欲减退、口渴喜饮具有较好的缓解和治疗效果,结合药物量效关系和经济成本等因素综合考虑,推荐连花柴芩可溶性粉临床应用剂量为2 g/L,饮水给药,连用5 d。  相似文献   
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