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1.
试验旨在探讨日粮钙水平对空怀期云南半细毛羊生长性能、配种前血清生化指标和繁殖相关激素的影响,为开展空怀期云南半细毛羊营养需要量研究提供参考。选用50只体况良好、体重相近、38月龄的经产2胎空怀云南半细毛羊,随机均分为5组,分别饲喂0.40%(无外源钙)、0.45%、0.53%、0.66%、0.85%5个钙水平的日粮。预试期14d,正试期30d。结果表明:0.53%钙水平组云南半细毛羊的总增重、平均日增重、平均日采食量、耗料增重比等指标相对优于其他组;0.40%钙水平日粮组的血清钙最高,血清碱性磷酸酶、甲状旁腺素、钙、磷组间差异不显著(P>0.05);繁殖相关激素各组间表现不一,0.40%钙水平组雌二醇水平最高(P>0.05)。在日粮磷水平为0.20%水平条件下,0.53%钙水平组的空怀期云南半细毛羊表现出较好的生长性能,可为临配种前生理生化和激素水平提供较好准备;增加日粮钙水平,未见对以上指标有明显的正向增强作用,可能与日粮钙磷比失衡有关。  相似文献   
2.
以朱顶红(Hippeastrum vittatum)叶片为外植体进行离体培养,具有取材方便、试材充足、成本低等优势,但叶片诱导再生率极低,是朱顶红离体培养的一大难题。本试验中分别以‘花孔雀’和‘黑天鹅’朱顶红无菌苗叶片为外植体,探究了不同植物生长调节剂和不同取材部位对不定芽诱导和继代增殖的影响。结果表明:最佳外植体为 MS 培养基中培养 10 d 形成的幼嫩叶片基部(0.5 cm),在光照 16 h · d-1(光照强度 36 μmol · m-2 · s-1)下,不定芽诱导的最适培养基为 MS + 2 mg · L-1 6-BA + 1 mg · L-1 NAA + 2 mg · L-1 TDZ,两个品种的不定芽均以间接途径发生,其中‘花孔雀’在培养 40 d 后形成愈伤组织,55 d形成不定芽,诱导率可达 69.44%;‘黑天鹅’在培养 45 d 后形成愈伤组织,65 d 形成不定芽,诱导率达到 66.67%;最适体细胞胚诱导培养基为 MS + 2 mg · L-1 6-BA + 1 mg · L-1 PIC,‘花孔雀’和‘黑天鹅’的诱导率分别达到 66.67%和 63.89%;最佳不定芽增殖培养基为 MS + 2 mg · L-1 6-BA + 1 mg · L-1 NAA + 1 mg · L-1 TDZ,‘花孔雀’和‘黑天鹅’的增殖系数分别达到 4.67 和 3.46;在不添加植物生长调节剂的 MS培养基中进行生根培养,30 d 后两个品种的生根率均达到 100%;将生根培养 30 d 的小植株转移至室温条件下放置 3 d,摘去封口膜再驯化 3 d 后,移栽至经高温消毒的草炭︰蛭石(体积比)为 1︰1 的基质中,成活率达到 100%  相似文献   
3.
Clostridium difficile (CD) is considered a major health care problem both in developing and developed countries; frequently reported to be associated with enterocolitis and diarrhea in horses and other animals. In this study, we examined acute phase response (APR), cytokines response, neopterin (NP) procalcitonin (PCT) production and oxidative stress condition in horses and foals with C. difficile-induced enterocolitis (CDIE) and evaluated the effectiveness of these parameters as biomarkers for the disease. A total of 407 Arabian horses in 35 stables were examined between January 2017 to December 2018. Only 24 out of 407 horses showed two or more signs of CDIE. The blood level of serum amyloid A (SAA), haptoglobin (HP), proinflammatory cytokines (TNF-α, IL-6 and IL1-β), serum malondialdehyde (MDA), PCT and NPT in horses with CDIE were higher than in healthy horses. Nevertheless, the levels of nitric oxide (NO), superoxide dismutase (SOD) and total antioxidant concentration (TAC) were considerably lower in diseased horses compared to those that were healthy. The ROC curves for eleven selected blood parameters, both in healthy horses and horses with CDIE demonstrated that all examined blood markers had significant levels of differentiation between CDIE cases and healthy controls (AUC > 87.5). The data in this study suggest that the evaluation of acute-phase proteins, cytokines, PCT, NPT, and oxidative stress biomarkers may well be used as a tool for diagnosis and assessment of CDIE and in disease pathogenesis in Arabian horses.  相似文献   
4.
5.

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   
6.
Serum and plasma are commonly used in clinical practice considering the widely accepted fact that the “normal” protein expression pattern of a healthy animal changes under disease conditions. We herein used a label-free mass spectrometry–based quantitative proteomics approach to characterize the serum proteome of donkeys. A total of 277 unique proteins were identified from 2,388 unique peptides. Gene ontology analyses showed that the most frequent processes were related to metabolic activities and biological regulation, response to stimulus, and immune system processes. The main annotated areas of origin were the extracellular region, extracellular region part, and organelle, and their molecular functions included binding, catalytic activity, and molecular function regulator. Analyses using the Clusters of Orthologous Groups for Eukaryotic Complete Genomes database indicated that the identified proteins could be categorized into three main groups: signal transduction mechanisms, amino acid transport and metabolism, and defense mechanisms. Most of the unique proteins were associated with the complement and coagulation cascades, and they participated in several disease-related metabolic pathways. Our results should be crucial for further analyses of changes in different physiological and pathophysiological conditions in donkeys.  相似文献   
7.
试验旨在研究饲粮中添加植物精油对广西灵山土鸡生长性能、养分表观消化率、血清抗体指标的影响。将1 800只30日龄、体重(284.09±1.18)g、体况良好的广西灵山土鸡,随机分为3组,每组3个重复,每个重复200只鸡,空白对照组饲喂基础饲粮,混合植物精油组、抗生素组分别在基础饲粮中添加100 mg/kg混合植物精油、325 mg/kg金霉素。预试期7 d,正试期30 d。结果表明:与对照组、抗生素组相比,混合植物精油组广西灵山土鸡末重、平均日增重、平均日采食量均提高(P<0.05);各组耗料增重比无显著性差异,且以混合植物精油组最低;各组间粗蛋白质、粗脂肪、钙、磷及能量的表观消化率均差异不显著;在67日龄时,混合植物精油组新城疫抗体水平高于其他两组(P<0.05),新城疫抗体水平、马立克抗体水平总体较52日龄呈下降趋势(P>0.05),以混合植物精油组下降幅度最低。可见,饲粮中添加植物精油显著提高了广西灵山土鸡的生长性能、新城疫抗体水平,但对养分消化率和马立克氏抗体无显著影响。  相似文献   
8.
急、慢性冷应激对雏鸡腓肠肌及血清抗氧化功能的影响   总被引:5,自引:0,他引:5  
【目的】探讨自由基在冷应激对禽类机体损伤中所起的作用,为探索促进动物冷适应的方法,提高动物的抗寒能力提供一定的理论依据;【方法】应用化学比色法检测了急、慢性冷应激对腓肠肌和血清中总抗氧化能力(T-AOC)、过氧化氢酶(CAT)活性、谷胱甘肽过氧化物酶(GSH-Px)活性、超氧化物歧化酶(SOD)活性及丙二醛(MDA)含量的影响;【结果】急性应激时,随应激时间的延长,腓肠肌T-AOC与SOD活性均逐渐降低,GSH-Px活性、CAT活性及MDA含量均逐渐升高,血清T-AOC逐渐降低,GSH-Px活性、CAT活性、SOD活性及MDA含量均逐渐升高;慢性应激时,随应激时间的延长,腓肠肌T-AOC、GSH-Px活性、CAT活性及SOD活性均逐渐升高,MDA含量逐渐降低,血清T-AOC、GSH-Px活性、CAT活性及MDA含量均逐渐升高,SOD活性逐渐降低;【结论】表明急、慢性冷应激均可使机体的抗氧化功能发生改变,诱发氧化胁迫,导致机体内自由基增多,对机体造成损伤。  相似文献   
9.
一种新的厌氧污泥比活性试验测定法   总被引:2,自引:0,他引:2  
赵亚乾 《中国沼气》1993,11(1):19-22
本文介绍了一种以医用血清瓶作发酵瓶、用医用注射器来量测所产沼气的厌氧污泥比活性试验测定法。实践表明此法简单实用、快速准确。  相似文献   
10.
Some animals routinely endure serious injuries from predators or during intraspecific territorial conflicts. Such is the case for Amphiuma tridactylum, an aquatic salamander that lives in an environment rich in potentially infectious microbes, apparently with rare or no pathogenic infection. Some vertebrates possess innate immune mechanisms, but whether this is the case for Amphiuma is unknown. To assess this potential, plasma from 19 A. tridactylum was pooled and used for characterisation of serum complement activity. The ability of A. tridactylum plasma to hemolyse unsensitised sheep red blood cells (SRBCs) was titer-dependent, with low activity observed even at high plasma titers. The kinetic characterisation of SRBC hemolysis revealed that significant activity could be measured within 10 min of incubation, and maximal activity occurred within 60 min. The SRBC hemolysis by A. tridactylum plasma was also temperature-dependent, with maximal activity at 30 °C. In addition, this activity was sensitive to mild heat treatment, with 96% of activity inhibited by incubation at 56 °C for 30 min. The SRBC hemolysis could also be inactivated by pretreatment of the plasma with proteases, indicating that this activity was protein dependent. The activity required divalent metals ions, with activity inhibited by EDTA, citrate, or phosphate. However, the chelator-inhibited activity could be restored by the addition of excess Ca2+ or Mg2+, but not Cu2+ or Ba2+, indicating specificity of the divalent metal ion requirement. The sensitivity to heat, proteases, and divalent metal ion chelators strongly suggests that A. tridactylum plasma-mediated hemolysis of SRBCs is mediated by the serum complement system of proteins.  相似文献   
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