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51.

Background

The acute phase proteins (APP) serum amyloid A (SAA), haptoglobin, and fibrinogen are valuable blood biomarkers in equine inflammatory diseases, but knowledge of factors influencing their concentrations in blood and peritoneal fluid (PF) of horses with colic is needed.

Objectives

The objective of this study was to investigate the influence of demographics (age, sex, breed), disease process (simple obstruction, strangulating obstruction, inflammatory), disease location, disease duration, hypovolemia, and admission hospital on concentrations of APP, lactate and white blood cell counts (WBC) in horses with colic admitted to 2 referral hospitals.

Animals

The study included 367 horses with colic admitted at 2 referral hospitals.

Methods

Prospective multicenter observational study of clinical data, as well as blood and PF biomarkers. Associations between biomarker concentrations and clinical variables were analyzed using multivariate linear regression analysis.

Results

Increasing pre‐admission duration of colic was associated with increased concentrations of APP in blood and PF. Blood concentrations of SAA and fibrinogen were associated with disease process (inflammatory, strangulations, simple obstructions) in more colic duration groups (5–12 and >24 hours) than any of the other biomarkers. No relevant associations between demographic factors, hospital, or hydration status and the measured biomarkers were found.

Conclusions and Clinical Importance

In horses with colic, concentrations of APP are associated mainly with disease process and duration of colic and may thus be used for assessment of disease independently of demographic or geographic factors. Serum amyloid A may be a diagnostic marker for use in colic differential diagnosis, but further evaluation is needed.  相似文献   
52.
新品系A系兔生长发育及部分特征特性测定   总被引:2,自引:1,他引:2  
对127只五世代的新品系A系兔进行测定,结果表明:A系兔早期增重较快、肉质良好。35日龄断奶个体重0.7kg左右,56日龄重1.3kg,90日龄重2.17kg,与德国白兔同期体重相近。断奶~56日龄、56~90日龄平均日增重分别为28g和26g,幼兔(断奶~90日龄)成少这96.06%,料重比为3.541。3月龄A系兔全净率51.14%、肉骨比为4.66:1。兔肉PH值6.21,失水率18.29%  相似文献   
53.
模拟干旱和盐胁迫下沙冬青种子硬实特性和抗逆性的研究   总被引:1,自引:1,他引:1  
将1~5 d内每天吸胀的沙冬青(Ammopiptanthus mongolicus)种子视为不同硬实程度的种子T1,T2,T3,T4和T5,与第5 d仍未吸胀的硬实种子(记作Tr)作为试材对其硬实特性和抗逆性进行研究,以期为沙冬青种子栽培驯化提供理论依据。结果表明:随着硬实程度的提高,种子的发芽势、发芽指数、活力指数呈上升趋势;电导率和丙二醛(MDA)含量逐渐下降;可溶性蛋白含量逐渐上升。不同处理对种子的硬实破除效果表明,80℃热水浸泡种子可达到最佳破除效果。通过测定模拟干旱胁迫和盐胁迫下不同硬实程度种子的超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性和脯氨酸(Pro)含量,表明在相同逆境条件下,随硬实程度的加深,除极个别外,各项指标值均有不同程度的升高,且一定胁迫强度下硬实种子萌发幼苗的各酶活性和脯氨酸含量均极显著高于其他萌发幼苗(P<0.01),因此,硬实种子比非硬实种子有较强的保护酶调节系统。硬实程度越高,耐旱和耐盐能力也随之升高。  相似文献   
54.
Bacteria from the nasal cavity and trachea were cultured, and serum antibody titers determined for Pasteurella haemolytica serotype 1 in 164 beef calves obtained from a closed herd on range pasture. At the first sampling, P. haemolytica serotype 1 was cultured from 16.4% of the calves. Antibody titers were determined by a quantitative fluorimetric method and the mean titer was 9.5 +/- 5.8. Fifty-seven randomly selected calves were used to study the correlation of serum antibody response and positive culture of P. haemolytica under natural conditions. Clinical signs of respiratory disease were not observed in those calves. During the observation periods, there was a two-fold increase in the percentage of calves that were culture positive. There was no significant difference between mean serum antibody titers or frequency distribution of antibody titers from the two samplings. Comparisons between serum antibody titers, rise in titers, and P. haemolytica isolation failed to reveal any significant correlation. Of the 9 calves that had a decline in antibody titer to P. haemolytica, none was culture positive. Seroconversion to respiratory viruses did not correlate with P. haemolytica related variables.  相似文献   
55.
猪繁殖与呼吸综合征病毒(porcine reproductive and respiratory syndrome virus,PRRSV)主要是通过与宿主细胞表面的特异性受体结合,利用细胞的内吞作用而感染易感细胞。作者对猪繁殖与呼吸综合征病毒相关受体的研究进行了综述,迄今已报道了5种独立的但功能相关的受体:硫酸乙酰肝素、唾液酸黏附素、波形蛋白、CD163和非肌肉肌动蛋白ⅡA。对受体的功能特性进行研究,将为PRRSV的感染机理和病毒性疾病的预防和治疗具有重要的意义。  相似文献   
56.
Opioids were found as factors affecting porcine ovarian steroidogenesis. The mechanism of opioid action, however, on porcine theca interna cells is completely unknown. Therefore, the present study was designed to investigate the possible involvement of two intracellular pathways, phospholipase C/protein kinase C and adenylyl cyclase/protein kinase A, in opioid signal transduction in porcine theca cells treated with mu opioid receptor agonist, FK 33-824. Incubation of the cells for 4 h with FK 33-824 at the dose 1 nM resulted in decreases in inositol phosphate accumulation as well as androstenedione (A(4)), testosterone (T), and estradiol (E(2)) secretions. Protein kinase C (PKC) inhibitors, staurosporine (1-100 nM), D-sphingosine (10-500 nM), and PKCi (100-2000 nM), both added alone and together with the opioid agonist, depressed release of the steroid hormones. PKC activator, phorbol ester (PMA, 1-100 nM), used alone was without effect on theca cell steroidogenesis, but added in combination with FK 33-824 abolished inhibitory influence of the opioid on A(4), T, and E(2) output. The steroid hormone secretion by PKC-deficient theca cells was inhibited by the opioid agonist. FK 33-824 also suppressed PKC activity reducing [(3)H]PDBu specific binding to theca cells, whereas ionomycin (a positive control) increased labeled phorbol ester binding to the cells. In the next experiment, cAMP release from theca cells during 2 and 4 h incubations with FK 33-824 (1-100 nM), naloxone (10 microM; opioid receptor antagonist), and LH (100 ng/mL; a positive control) was examined. FK 33-824 at the dose 1 nM inhibited cAMP secretion during 2 h incubation, but had no effect during longer incubation. LH in a manner independent on incubation time multiplied cAMP release. Protein kinase A inhibitor, PKAi (100-2000 nM), alone and in combination with FK 33-824 (1 nM), inhibited A(4), T, and E(2) secretions by theca cells. PKA activator, 8BrcAMP (10-1000 microM), stimulated the steroid hormone release, but this stimulatory effect was diminished in the presence of FK 33-824. The results allow to suggest that opioid peptides affect porcine theca cell steroidogenesis and their acute action on the cells is connected with the inhibition of phospholipase C/protein kinase C and adenylyl cyclase/protein kinase A signal transduction systems.  相似文献   
57.
围产期奶牛能量代谢障碍性疾病的防治进展   总被引:5,自引:0,他引:5  
奶牛代谢性疾病给奶牛饲养业造成重大经济损失。因此 ,如何搞好奶牛的饲养管理 ,减少代谢病的发生 ,充分发挥其生产潜力 ,是当前奶牛代谢病防治工作中亟待解决的问题。本文主要阐述了围产期奶牛能量代谢障碍病的危害、病因及防治措施  相似文献   
58.
泰乐菌素发酵过程中,PH值的控制及豆油的补加量对组份的转化存在显著影响。研究结果表明,在转化阶段当PH值控制在适当范围内,对不菌素效价影响不大,但可大大提高泰乐菌素A的含量;同时在发酵中期及转化前这一阶段补加适量豆油,不仅可使效价逐步提高,还中明显促进大菌C向泰乐菌素A的转化。  相似文献   
59.
本文在介绍维生素A和维生素D营养生理功能的基础上,综述了维生素A和维生素D对相关基因表达的调控及其主要机制。  相似文献   
60.
通过3因素5水平二次通用正交旋转组合设计方案,建立回归模型,进行解析、寻优和频数分析。结果表明:各试验因素对蓝茎冰草(Pascopyrum smithii)种子产量影响的大小顺序为施氮量(X2)>植株密度(X1)>喷施PP 333(X3);施氮量与植株密度的互作效应对种子产量的作用为协同效应;同时得出了3因素对种子产量的优化配比方案:植株密度429.4~450×104株/hm2,施氮量160~164.9kg/hm2,喷施PP 333量0.197~0.233 a.i.kg/hm2。  相似文献   
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