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1.
围产期奶牛经历妊娠、分娩、泌乳以及高精料饲喂等一系列代谢应激及外部环境的变化,极易诱发奶牛机体产生氧化应激,进而导致抗氧化功能下降及免疫功能失调,诱发奶牛产生代谢病和炎性疾病。因此,缓解奶牛机体的氧化应激是实现奶牛高生产力的有效方式。茶多酚作为一种绿色无公害的天然抗氧化剂,将其合理地添加到奶牛的日粮中,能够提高奶牛机体的抗氧化性,有效缓解因氧化应激出现的炎性反应、免疫功能失调等问题。文章围绕由氧化应激引起的围产期奶牛代谢病和炎性疾病的发病机制以及茶多酚的调控作用进行综述,旨在为后续在奶牛生产中应用茶多酚提供思路。  相似文献   

2.
维生素E和微量元素硒是重要的抗氧化物质,在保护机体方面有着不可替代的作用。越来越多的研究表明,奶牛乳房炎的发生与机体维生素E和硒(Se)的缺乏有关。本文综述了维生素E和Se在降低奶牛乳房炎发病率中的作用。  相似文献   

3.
中草药用于防治奶牛(山羊)乳房炎不但具有副作用小、不产生耐药性、免疫学功效明显的优点,还具有免疫佐剂的作用和抗菌(抑菌)、消炎等特点,中草药防治奶牛(山羊)乳房炎的应用前景非常广阔。  相似文献   

4.
为研究奶牛亚临床酮病与乳房炎的关系以及血液中的酮体成分对奶牛抗氧化功能的影响,以156头健康荷斯坦奶牛为试验动物(SCC〈200000/mL),共筛选亚临床酮病奶牛69头(1.0mmol/L≤BHBA〈2.6mmol/L)作为试验组,根据年龄、胎次、产奶量、泌乳天数配对的69头奶牛作为时照组(血液BHBA〈1.0mmol/L),监测乳房炎发病情况并在各组中选取12头奶牛检测血液酮体水平和抗氧化指标。结果表明亚临床酮病奶牛试验期间乳房炎的发病率为43.48%,对照组试验期间乳房炎的发病率为31.88%,但差异不显著(P〉0.05);试验组奶牛乳房炎高发期为分娩后3~6周,对照组奶牛乳房炎发病时间为分娩后5~8周,亚临床酮病发病后1~3周内为乳房炎的高发期,占试验组奶牛乳房炎总发病比例的73.33%,试验组和对照组病原菌的组成无显著差异(P〉0.05);试验组奶牛血液中T—AOC显著低于对照组(P〈0.05),GSH—PX活力、MDA和N0显著高于对照组(P〈0.05),血液ACAC浓度与GSH—PX活力呈显著正相关(P〈0.05,r=0.595),ACAC浓度与NO呈显著正相关(P〈0.05,r=0.655),T—AOC与MDA呈显著负相关(P〈0.05,r=0.533)。结果表明奶牛亚临床酮病可以导致乳房炎的发病率升高,但不是主要影响因素,亚临床酮病对乳房炎病原体构成无影响;外周血酮体水平升高导致机体总抗氧化能力的降低并引起机体脂质过氧化反应;谷胱甘肽过氧化物酶在发挥抗氧化功能时具有一定的抵抗力和自我调节能力。  相似文献   

5.
奶牛乳房炎(Dairy mastitis)又称奶牛乳腺炎,是乳腺受到物理、化学、微生物刺激所发生的一种炎性反应,导致患病奶牛乳房出现红、肿、热、痛和机能障碍等症状.美国国家奶牛乳房炎委员会(NMC1987)以乳房和乳汁有无肉眼变化,将乳房炎分为临床型乳房炎(Clinical mastitis)、亚临床型乳房炎(Subclinical mastitis)或称隐性乳房炎(Hiddex mastitis).  相似文献   

6.
在过去的奶牛育种工作中,一直把产奶量作为奶牛改良最重要的指标。这种片面性的选育,导致奶牛疾病的大量发生,乳房炎就是其中危害最大的常见病之一。乳房炎不仅影响奶牛健康,降低产奶量,还会使奶产品的质量下降。因此,减少乳房炎的发病率是目前奶牛业亟需解决的问题。从遗传选育角度来看,应该把抗病选育作为未来奶牛育种工作中的重点。牛乳中的体细胞(Somatic Cell Count,SCC)数量反映了牛奶产量、质量及牛只的健康状况,SCC在奶牛育种中具有广阔的应用前景。可以通过奶牛群体改良(DHI)测定,得到大量可靠的奶牛个体生产性能数据(包括SCC),结合育种学理论进行奶牛选育,从而降低疾病的发生率,提高奶牛业的经济效益。  相似文献   

7.
奶牛多形核白细胞凋亡的分子调控与乳腺免疫   总被引:1,自引:1,他引:0  
多形核白细胞(polymorphonuclear neutrophil leukocytes,PMN)在奶牛乳腺防御病原菌感染中充当首要防线,而PMN的凋亡在解除奶牛乳腺的炎性反应中发挥关键作用。作者综述了PMN凋亡的分子调控及其在奶牛乳腺免疫中的重要作用和意义。  相似文献   

8.
为开发安全、有效、稳定的新型中兽药制剂,有利于奶牛隐性乳房炎的防治,试验研究了中药透皮剂对隐性乳房炎奶牛泌乳量、白细胞、白蛋白(ALB)、丙氨酸氨基转移酶(ALT)、乳酸脱氢酶(LDH)的影响。方法:记录用药前后5d日泌乳量,分别采用试剂盒和CA-500血液分析仪测定用药前后乳汁中ALB、ALT、LDH和血液中白细胞。结果:患隐性乳房炎奶牛泌乳量显著降低(P〈0.05),血液中WBC、MON、GRA、LYM%显著高于健康牛(P〈0.05),而乳汁中的ALB、ALT和LDH含量极显著高于健康奶牛(P〈0.01)。通过5d中药透皮剂治疗后,奶牛产奶量大幅度增加,WBC、MON、GRA、LYM%、ALB、ALT和LDH与健康牛比差异不显著(P〉0.05)。结论:中药透皮剂对奶牛隐性乳房炎具有良好的治疗效果。  相似文献   

9.
为了发挥DHI体系在奶牛生产管理中的作用,促进奶牛健康养殖和乳品质量的提高,本研究利用DHI技术对包头某奶牛场6个月的奶牛生产情况进行了分析。结果发现,该奶牛场奶牛的乳脂率较低,体细胞数较高,一些奶牛患有严重的临床性乳房炎或隐性乳房炎。奶牛营养状况差,泌乳高峰期到达时间晚,产奶量少,存在潜在的奶损失。针对上述问题,提出了相应的解决措施。  相似文献   

10.
重庆部分地区泌乳奶牛乳房炎的病因及发病情况调查   总被引:12,自引:0,他引:12  
对重庆部分地区6个奶牛场118头泌乳奶牛进行临床型乳房炎的病因及发病情况调查,并对其中76头泌4乳奶牛进行隐性乳房炎检查。同时对226份患乳房炎和健康奶牛奶样进行细菌学分离鉴定,结果表明:临床型乳房炎奶牛及阳性乳区分别为8.47%(10/118)和3.32%(15/452);隐性乳房炎奶牛及阳性乳区分别为78.94%(60/76)和50.34%(148/294);临床型乳房炎、隐性乳房炎奶牛的阳性  相似文献   

11.
类黄酮对蛋鸡脂类代谢的影响   总被引:36,自引:1,他引:35  
270只31周龄海赛克斯褐壳蛋鸡,随机分为9个处理。试验2-5组日粮分别添加5mg/kg、10mg/kg、20mg/kg、40mg/kg茶多酚,试验6-9组日粮分别添加5mg/kg、10mg/kg、20mg/kg、40mg/kg大豆黄酮。试验为期8周。研究茶多酚(多酚类黄酮)、大豆黄酮(二酚类黄酮)对蛋鸡生产性能的影响,并从脂类代谢角度探讨类黄酮对蛋鸡的作用柚是及其可能的作用途径。结果表明:(1)茶多酚和大豆黄酮均显著地降低蛋黄甘油三酯,降低最大幅度分别为14.7%和16.7%(P<0.05)。(2)40mg/kg茶多酚或10mg/kg大豆黄酮有降低血浆总胆固醇、甘 一酯、LDL-C的趋势。(3)茶多酚和大豆黄酮均显著升高了蛋鸡血浆雌二醇和胰岛素的水平。(4)茶多酚和大豆黄酮有提高产蛋率的作用,尤其添加10mg/kg大豆黄酮,产蛋率显著提高7.2%(P<0.05)。  相似文献   

12.
Background: Vascular endothelial growth factor A(VEGFA) can induce endothelial cell proliferation, promote cell migration, and inhibit apoptosis. These processes play key roles in physiological blood vessel formation and pathological angiogenesis.Methods: In this study, we examined VEGFA gene expression in the heart, liver, and kidney of Tibetan pigs(TP), Yorkshire pigs that migrated to high altitudes(YH), and Yorkshire pigs that lived at low altitudes(YL).We used PCR and Sanger sequencing to screen for single nucleotide polymorphisms(SNPs) in 5'-flanking DNA and exons of the VEGFA gene. Quantitative real-time PCR and western blots were used to measure expression levels and PCR products were sequenced.Results: Results showed that the VEGFA m RNA and protein expression in heart, liver and kidney of TP was higher than that in YH and YL. In addition, the m RNA sequence of the pig VEGFA gene was conserved among pig breeds, and only five SNPs were found in the 5'-flanking region of the VEGFA gene, the allele frequency distributions of the 5 SNPs were not significantly different between the TP, Yorkshire(YL), and Diannan small-ear(DN) pig populations.Conclusion: In conclusion, the Tibetan pig showed high levels of VEGFA gene expression in several hypoxic tissues, which suggests that the VEGFA gene may play a major functional role in hypoxic adaptation.  相似文献   

13.
[目的]通过研究羊胎盘转移因子注射液对健康大白鼠、人工创伤模型大白鼠和健康杂种幼犬的血浆总蛋白(TP)、白蛋白(ALB)、超氧化物歧化酶(SOD)、一氧化氮(NO)和血红蛋白(Hb)含量的影响,探讨供试药品对受试动物的营养作用,进而评估其临床营养功效。[方法]将24只健康大鼠和16只健康杂种幼犬分别随机分为试验组和对照组,为试验组大鼠和试验组幼犬灌服供试药品,并检测给药前后血浆TP、ALB和Hb含量的变化。将45只健康大鼠人工创伤造模后分成低剂量试验组、中剂量试验组和对照组3个组,试验组大鼠使用不同剂量供试药品,于术后3、7、14d测定血浆TP、ALB、SOD和NO含量的变化。[结果]①为健康大鼠灌服供试药品后,与对照组相比,试验组健康大鼠血浆TP、ALB含量显著(P0.05)提高。②为健康杂种幼犬灌服供试药品后3d,与对照组相比,试验组健康杂种幼犬血浆中TP、Hb含量均极显著(P0.01)提高,ALB含量显著(P0.05)提高。③为人工创伤模型大鼠灌服供试药品后,与对照组相比,各试验组术后3d血浆TP、ALB、NO含量均提高;术后7 d中剂量组血浆TP、ALB、NO含量均极显著提高(P0.01),低剂量组显著提高(P0.05);术后14 d,试验组血浆TP、ALB含量恢复到术前,试验组血浆NO含量升高,无显著差异(P0.05)。与对照组相比,术后3 d和7 d,各试验组血浆SOD含量升高,无显著差异(P0.05);术后14d,各试验组SOD含量升高,中剂量组显著(P0.05)升高。[结论]羊胎盘转移因子注射液可显著改善健康大鼠和健康杂种幼犬的营养状况,促进术后大鼠创伤恢复和幼犬的生长发育,提高机体抗病能力,在临床上兼具改善营养和提高免疫力的作用。  相似文献   

14.
This review focuses on techniques for achieving very low concentration of TN and TP in water.The 1970 Clean Water Act in the US and the Urban Waste Water Treatment Directive in Europe now provide the benchmark standards for TN and TP levels.Arden and Lockett discovered activated sludge in the 1910’s.Since then,many improvements have been made to the biological treatment process to provide various configurations that have the ability to deliver effluent concentrations between 6-8mg TN/L and 0.5-1.0mg TP/L,without external carbon addition.Typically,however,additional advanced nutrient removal technologies are used in tertiary treatment to meet more stringent effluent quality requirements.One advanced technology that has been successfully implemented in the US is denitrifying filters.For TP removal,tests showed that the BlueP RO and CoM ag systems both reliably met an effluent target as low as 0.04 mg TP/L.However,the establishment of stringent TN and TP effluent limits will dramatically increase the capital and operational costs of wastewater treatment plants.A more promising nutrient capturing process is based on the assimilation of nutrients(both N and P)during heterotrophic growth which uses a carbon source for energy.Laboratory trials of the single step process by Reach Green suggest that concentrations as low as 0.5 mg TN/L and 0.02mg TP/L are readily achievable.  相似文献   

15.
MicroRNAs (miRNAs) are important regulators of gene expression and are known to play a key role in regulating both adaptive and innate immunity. Bovine alveolar macrophages (BAMs) help maintain lung homeostasis and constitute the front line of host defense against several infectious respiratory diseases, such as bovine tuberculosis. Little is known, however, about the role miRNAs play in these cells. In this study, we used a high-throughput sequencing approach, RNA-seq, to determine the expression levels of known and novel miRNAs in unchallenged BAMs isolated from lung lavages of eight different healthy Holstein–Friesian male calves. Approximately 80 million sequence reads were generated from eight BAM miRNA Illumina sequencing libraries, and 80 miRNAs were identified as being expressed in BAMs at a threshold of at least 100 reads per million (RPM). The expression levels of miRNAs varied over a large dynamic range, with a few miRNAs expressed at very high levels (up to 800,000 RPM), and the majority lowly expressed. Notably, many of the most highly expressed miRNAs in BAMs have known roles in regulating immunity in other species (e.g. bta-let-7i, bta-miR-21, bta-miR-27, bta-miR-99b, bta-miR-146, bta-miR-147, bta-miR-155 and bta-miR-223). The most highly expressed miRNA in BAMs was miR-21, which has been shown to regulate the expression of antimicrobial peptides in Mycobacterium leprae-infected human monocytes. Furthermore, the predicted target genes of BAM-expressed miRNAs were found to be statistically enriched for roles in innate immunity. In addition to profiling the expression of known miRNAs, the RNA-seq data was also analysed to identify potentially novel bovine miRNAs. One putatively novel bovine miRNA was identified. To the best of our knowledge, this is the first RNA-seq study to profile miRNA expression in BAMs and provides an important reference dataset for investigating the regulatory roles miRNAs play in this important immune cell type.  相似文献   

16.
本研究旨在抗菌肽Tachyplesin Ⅰ(TP Ⅰ)的结构活性基础上,重新设计一种全新的抗菌肽TP Ⅰ-Y4。保持母肽链长与电荷数不变,将序列中形成TP Ⅰ两个二硫键的4个半胱氨酸用酪氨酸进行替换后得到TP Ⅰ-Y4。经生物信息学软件分析,与TP Ⅰ相比,TP Ⅰ-Y4的热稳定性更好,亲水性更强,同时具有与母肽相似的结构与抗菌活性。化学合成后经圆二色谱检测发现,TP Ⅰ-Y4在水相及在模拟细胞膜疏水环境的50%三氟乙醇中都表现出β-折叠结构,疏水环境中TP Ⅰ-Y4的β-折叠含量高于水相,也高于不同环境中的TP Ⅰ。抑菌试验表明,TP Ⅰ-Y4对细菌和真菌都有较强抑菌活性,且对细菌的抑菌活性强于TP Ⅰ。TP Ⅰ-Y4对小鼠红细胞溶血性降低,并保留了很强的内毒素中和能力,浓度为40 μg·mL-1时中和率可达50%以上。TP Ⅰ-Y4抗菌活性的提高以及溶血活性的降低,可能与β-折叠强形成者酪氨酸的替代有关,进而导致抗菌肽分子中β-折叠结构增强。  相似文献   

17.
何应  马向丽  任健  代微然  毛如志 《草业科学》2022,1(1):2294-2300
防御酶是植物对昆虫危害的潜在防御机制。毛花雀稗(Paspalum dilatatum)作为一种优良牧草,了解被昆虫取食胁迫后其防御酶的变化很有必要。为此,本研究分析了蝗虫(Oxya chinensis)取食毛花雀稗0 (CK)、24、48、72和96 h后毛花雀稗总抗氧化能力(total antioxidant capacity, T-AOC)、过氧化物酶(peroxidase, POD)、过氧化氢酶(catalase, CAT)、超氧化物歧化酶(superoxide dismutase, SOD)、酪氨酸解氨酶(tyrosine ammonia-lyase, TAL)、多酚氧化酶(polyphenol oxidase, PPO)、脂氧合酶(lipoxygenase, LOX)、谷胱甘肽S-转移酶(glutathione S-transferase, GST)、苯丙氨酸解氨酶(phenylalanine ammonia-lyase, PAL)活性及植物总酚(total phenols, TP)含量的变化规律。结果表明:与不取食对照相比,蝗虫取食后毛花雀稗植株中POD、CAT、LOX、PPO、TAL、GST活性以及TP含量均在部分取食时间或所有取食时间显著升高(P < 0.05)。其中T-AOC在24 h时显著升高(P < 0.05);TAL、PPO和GST活性均随取食时间的延长呈先升高后降低的变化趋势,分别在48、72和24 h时达到最高,是对照的3.71、2.10和21.25倍。相反,除24 h时SOD活性外,SOD、PAL活性在蝗虫取食胁迫下均显著降低(P < 0.05)。可见,POD、CAT、PPO、TAL、GST和LOX等防御酶在毛花雀稗防御害虫胁迫中发挥了非常重要的保护作用。  相似文献   

18.
A feedlot growth-performance trial and a metabolism trial were conducted to evaluate the comparative feeding value of tapioca pellets (TP). In the growth-performance trial treatments consisted of a steam-flaked corn (SFC)-based finishing diet in which a blend of 86% TP and 14% peanut meal replaced SFC at the rate of 0, 15, or 30% of diet DM. Daily weight gain (P less than .10) and DM intake (P less than .01) were greatest when 15% of the diet DM consisted of TP. Feed/gain increased linearly (P less than .01) with TP substitution into the diet. Treatment effects on carcass merit were small (P greater than .10), except that marbling score was greater with 15% TP than with either 0 or 30% TP. In the metabolism trial involving four Holstein steers, treatments consisted of an 88% concentrate diet containing 67% of either SFC or TP. Ruminal and total tract digestibility of starch was similar (P greater than .10) for SFC and TP, averaging 91 and 99%, respectively. Postruminal (P less than .05) and total tract (P less than .01) digestibility of N was lower for the TP than for the SFC diet. Total tract digestibility of N in TP was 3%. Little, if any, ADF in TP was fermented in the rumen. Total tract digestibility of ADF in TP was 16%. Total tract digestibility of DM (P less than .01) and OM (P less than .05) decreased 7 and 5%, respectively, with TP substitution for SFC. Virtually all the difference in OM digestibility could be attributed to differences in ADF excretion. The DE value of the diet decreased 11.5% (P less than .01) with the substitution of TP for SFC. It was concluded that TP can replace up to 30% of the DM in growing-finishing diets without adversely affecting ADG or DM intake of feedlot cattle. Tapioca pellets have approximately 86% the NE value of SFC.  相似文献   

19.
Objective— To investigate mutations of the TP53 gene in canine osteosarcoma (OS).
Study Design— Clinical historic cohort study.
Animals— Client-owned dogs.
Methods— OS (n=59) were screened for mutations of the complete TP53 gene using polymerase chain reaction and the mutation was analyzed by single-strand conformational polymorphism. Clinical outcome of dogs with TP53-mutated OS were compared with dogs with OS without a mutation after complete surgical excision of the primary tumor.
Results— TP53 gene mutations were observed in 24 of 59 (40.7%) OS; 3 mutated OS had 2 mutations. The alterations consisted mainly of point mutations (74%). Dogs with mutated OS had a significantly shorter survival time (ST) after surgery than dogs with normal tumor TP53 gene expression ( P =.03). Other significant prognosticators for ST and disease-free interval included elevated serum alkaline phosphatase ( P <.01) and tumor grade ( P =.01).
Conclusion— TP53 genetic mutations are common in canine OS and may have a prognostic value.
Clinical Relevance— Mutations of the TP53 gene may influence survival and should be considered when evaluating canine OS.  相似文献   

20.
本试验采用单因子试验设计研究茶多酚与L-茶氨酸在热应激下对蛋用仔公鸡生长性能及抗氧化能力的影响。选用1日龄蛋用仔公鸡180只,随机分为6组,每组3个重复,每个重复10只鸡。试验1组为对照组,饲喂基础日粮;试验2~6组分别在基础日粮中添加400 mg/kg茶多酚、200 mg/kg L-茶氨酸、200 mg/kg茶多酚+200 mg/kg L-茶氨酸、400 mg/kg茶多酚+200 mg/kg L-茶氨酸、600 mg/kg茶多酚+200 mg/kg L-茶氨酸,试验期28 d。结果表明,茶多酚可有效降低热应激下蛋用仔公鸡的料重比(P<0.05),L-茶氨酸单独添加或与茶多酚同时添加对生长性能影响均不显著(P>0.05);茶多酚可显著降低各组织器官的丙二醛(MDA)含量 (P<0.05),显著提高各组织器官的谷胱甘肽过氧化物酶(GSH-Px)与过氧化氢酶(CAT)活性(P<0.05);L-茶氨酸能显著提高各组织器官的CAT活性(P<0.05),不同程度降低各组织器官的MDA含量;茶多酚与L-茶氨酸同时添加时,抗氧化能力与茶多酚的添加量不呈正比;400 mg/kg茶多酚+200 mg/kg L-茶氨酸组肝脏样总超氧化物歧化酶(T-SOD)与GSH-Px活性均显著降低(P<0.05),MDA含量显著提高(P<0.05)。在热应激条件下,200 mg/kg茶多酚+200 mg/kg L-茶氨酸同时添加时,抗氧化效果较理想。  相似文献   

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