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31.
N6-甲基腺嘌呤(N6-methyladenosine,m6A)修饰是现阶段发现的真核生物体内最广泛的RNA表观遗传修饰方式,近年来研究显示,m6A在真核生物间具有较高的保守性,在基因表达及细胞命运调控中发挥着关键作用,且对mRNA的可变剪接、定位、翻译及稳定性有较大影响。现有的m6A修饰检测技术可以较为准确、高效地检测出生物样本中的m6A修饰丰度,并能快速、简便地进行m6A修饰的高通量测序,以及在单碱基分辨率下检测m6A修饰在RNA上的位置。尽管m6A修饰相关调控蛋白对畜禽复杂经济性状的影响近年来已有少量报道,但其中的作用机制仍未得到充分阐明。大量人类及模式生物上的研究表明,m6A修饰相关蛋白能够影响生长发育、繁殖、热应激、炎症及癌症等生物学过程,为探究畜禽m6A修饰参与复杂性状调控机制提供一定的借鉴意义。作者主要从m6A甲基化修饰相关蛋白(甲基转移酶、去甲基化酶及读取蛋白)、m6A检测技术、m6A对哺乳动物复杂性状的调控机制、m6A与其他表观修饰的互作机制等方面进行阐述,为m6A在畜禽遗传育种中的应用提供新的见解。 相似文献
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A survey was conducted in 10 districts of northern India. Significant deficiency of zinc was observed in soil, fodders and (cattle) serum samples. The animals showed typical signs of zinc deficiency, namely stiff gait, swelling of hocks and knees, subcutaneous fluid accumulation, rough coat, etc. of variable intensity. A clustered model therapeutic trial was conducted and zinc-deficient cattle were divided into three groups. Group A was provided with mineral mixture containing zinc sulphate. Group B was given mineral mixture without zinc sulphate and group C was given no mineral mixture. Significant improvement (p < 0.01) was observed in the haemoglobin (Hb), total white blood cells (WBC) and total erythrocyte count (TEC) levels at the 7th day of treatment in the animals of group A. Significant improvement in enzyme serum alkaline phosphatase (SAP) was observed in group A animals at the 7th day, while improvement in asparatate aminotransferase (AST), alanine aminotransferase (ALT) and ceruloplasmin (Cp) was observed after 21 days of treatment. Regarding hormones, significant improvement was observed in thyroxine (T3) and triiodothyronine (T4), oestrogen and progesterone in group A animals within 14 days of treatment. The values of vitamin A showed a highly significant (p < 0.01) improvement within 7 days of treatment in group A animals and that of vitamin E on the 21 st day of treatment. The milk yield of lactating cattle and body weight of growing calves in group A showed highly significant (p < 0.01) increases at about 14 and 30 days, respectively. It is concluded that zinc sulphate supplementation is highly effective in alleviating zinc deficiency and improving various biochemical and production parameters in cattle. The clustered model treatment provides a better indicator of the most limiting element under field conditions where simultaneous deficiency of various minerals is prevalent. 相似文献
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内毒素诱生自由基致兔血循环系统损伤及CA对其影响 总被引:2,自引:1,他引:2
将56只健康白兔随机分组:正常对照组( 组)8只,ET处理组( 组)、CA保护组( 组)各24只,第1、2、3、4和5小时分别采集血液制备血浆样品,检测血浆T-AOC、T-SOD活性和MDA含量,第2和第5小时捕杀并迅速采集心脏制备组织匀浆,检测心脏GSH、GSH-ST、GSH-Px活性,研究内毒素(endotoxin,ET)诱导休克兔产生自由基对血浆和心脏的损伤及阳离子A(cationA,CA)对其影响。结果表明: 组各项指标均保持相对稳定; 组MDA含量比 组升高(P<0.01),T-AOC、T-SOD活性比 组降低(P<0.01),而 组的MDA、T-AOC、T-SOD显著高于 组(P<0.05);除心脏GSH-Px活性第5小时降低不明显外, 组GSH、GSH-Px和GSH-ST活性显著降低(P<0.01), 组比 组GSH、GSH-Px、GSH-ST活性高(P<0.01)。结果提示:CA能减轻ET诱生自由基所致的过氧化损伤,有效缓解内毒素引起的血液循环系统毒性损伤。 相似文献
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Low‐pathogenicity avian influenza (LPAI) viruses have caused illness in poultry and humans with poultry contact. To determine whether there is evidence of exposure to avian influenza viruses (AIV) among backyard poultry in Minnesota and their human caretakers, 150 flocks of backyard birds were sampled for antibodies to AIV from August 2007 through December 2008. One hundred flocks were tested through routine slaughter surveillance by the Minnesota Board of Animal Health and an additional 50 flocks were contacted and sampled by study investigators. Blood was collected from 10 to 13 birds from each flock and a survey of biosecurity and management practices was administered to the flock owner. Blood samples were tested by agar gel immunodiffusion (AGID) for influenza A antibodies. Tested flocks had a median flock size of 100 birds (range: 12–800 birds), and were most commonly owned for meat for personal use (81% of respondents), fun or hobby (58%) and eggs for personal use (56%). Although 7% of flock owners reported that their birds had shown respiratory signs in the previous 3 months, only 1 of 150 flocks tested positive for influenza by AGID. Antibodies to LPAI H6N1 were detected in the positive flock. The owner of the positive flock did not have antibodies to H6 or other common AIV. Based on the findings of this study, the risk of transmission of LPAI viruses from backyard poultry to owners in Minnesota appears to be low under current conditions and management practices. 相似文献
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本研究旨在探讨铜和维生素A及其互作效应对内仔鸡生长性能及抗氧化功能的影响.试验选用1日龄艾维茵肉仔鸡448只,随机分为8组,每组4个重复,每个重复14只鸡.采用4×2(铜×维生素A)完全随机设计,饲粮铜的添加量分别为0、8、150、225 mg/kg,维生素A的添加量分别为1 500、5 000 IU/kg,分为2个生长阶段,前期为1~4周龄,后期为5~7周龄.结果表明:1)高铜( 150、225mg/kg)抑制了全期肉仔鸡生长性能,提高了全期血清铜蓝蛋白(Cp)和后期血清总超氧化物歧化酶(T-SOD)活性(P<0.05).2)5 000 IU/kg维生素A组获得较好的生长性能,提高了全期血清T-SOD活性,降低了前期血清Cp活性(P<0.05).3)铜和维生素A互作效应对前期体增重、血清Cp和T-SOD活性及全期料重比有显著影响(P<0.05),且二者间存在互补作用.铜(8 mg/kg)×维生素A(5 000 IU/kg)组与铜(0 mg/kg)×维生素A(5 000 IU/kg)组对前期肉仔鸡获得良好生长性能和提高血清T-SOD活性均有促进作用,但对血清Cp活性有显著降低作用(P<0.05).由此可见,在基础饲粮铜水平为16~23mg/kg时,铜的适宜添加量为前期8 mg/kg,后期0~8 mg/kg;全期维生素A的适宜添加量为5 000 IU/kg. 相似文献
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Antigenic Detection of Human Strain of Influenza Virus A (H3N2) in Swine Populations at Three Locations in Nigeria and Ghana during the Dry Early Months of 2014 下载免费PDF全文
Since the first detection of human H3N2 influenza virus in Taiwanese pigs in 1970, infection of pigs with wholly human viruses has been known to occur in other parts of the world. These viruses, referred to as human‐like H3N2 viruses, have been known to cause clinical and subclinical infections of swine populations. Due to the paucity and complete unavailability of information on transmission of influenza viruses from other species, especially humans, to swine in Nigeria and Ghana, respectively, this study was designed to investigate the presence and prevalence of a human strain of influenza A (H3N2) in swine populations at three locations in two cities within these two West African countries in January and February, 2014. Using stratified random technique, nasal swab specimens were collected from seventy‐five (75) pigs at two locations in Ibadan, Nigeria and from fifty (50) pigs in Kumasi, Ghana. These specimens were tested directly by a sensitive Quantitative Solid Phase Antigen‐detection Sandwich ELISA using anti‐A/Brisbane/10/2007 haemagglutinin monoclonal antibody. Influenza virus A/Brisbane/10/2007 (H3N2) was detected among pigs at the three study locations, with an aggregate prevalence of 4.0% for the two locations in Ibadan, Nigeria and also 4.0% for Kumasi, Ghana. Transmission of influenza viruses from other species to swine portends serious sinister prospects for genetic reassortment and evolvement of novel viruses. We therefore recommend that further studies should be carried out to investigate the presence of other circulating human and avian influenza viruses in swine populations in West Africa and also determine the extent of genetic reassortment of strains circulating among these pigs. This would provide an early warning system for detection of novel influenza viruses, which could have pandemic potentials. 相似文献
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【目的】研究水牛主要促进因子超家族成员2a(major facilitator superfamily domain containing 2a, MFSD2A)基因多态性,并筛选与水牛产奶性状相关联的SNP。【方法】采集383头健康水牛血液DNA,利用PCR扩增和Sequenom MassARRAY飞行时间质谱技术对SNP位点进行筛选及基因型检测,并进行遗传多样性、连锁不平衡(LD)和单倍型分析,以及对不同基因型和单倍型与水牛产奶性状进行关联分析。【结果】在水牛MFSD2A基因中检出7个SNPs位点,多态信息含量(PIC)均在0.25~0.40之间,属于中度多态,除g.8290 T>C位点外,其余位点均处于Hardy-Weinberg平衡状态(P>0.05);关联分析结果表明,这7个SNPs位点与305 d产奶量均显著关联(P<0.05),且突变杂合子基因型的305 d产奶量是3种基因型中最低的,g.568 C>G和g.701 A>G位点与乳脂率显著关联(P<0.05),乳脂率从大到小依次为突变纯合子>野生纯合子>突变杂合子,g.568... 相似文献
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