Replacing fish oil and astaxanthin by microalgal sources produced different metabolic responses in juvenile rainbow trout fed 2 types of practical diets

Dietary fish oil supplementation provides n-3 long-chained polyunsaturated fatty acids for supporting fish growth and metabolism and enriching fillet with eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; c22:6n-3). Two experiments were performed as a 3 × 2 factorial arrangement of dietary treatments for 16 wk to determine effects and mechanisms of replacing 0%, 50%, and 100% fish oil with DHA-rich microalgae in combination with synthetic vs. microalgal source of astaxanthin in plant protein meal (PM)- or fishmeal (FM)- based diets for juvenile rainbow trout (Oncorhynchus mykiss). Fish (22 ± 0.26 g) were stocked at 17/tank and 3 tanks/diet. The 100% fish oil replacement impaired (P < 0.0001) growth performance, dietary protein and energy utilization, body indices, and tissue accumulation of DHA and EPA in both diet series. The impairments were associated (P < 0.05) with upregulation of hepatic gene expression related to growth (ghr1and igf1) and biosynthesis of DHA and EPA (fads6 and evol5) that was more dramatic in the FM than PM diet-fed fish, and more pronounced on tissue EPA than DHA concentrations. The source of astaxanthin exerted interaction effects with the fish oil replacement on several measures including muscle total cholesterol concentrations. In conclusion, replacing fish oil by the DHA-rich microalgae produced more negative metabolic responses than the substitution of synthetic astaxanthin by the microalgal source in juvenile rainbow trout fed 2 types of practical diets.     

Sequence and phylogenetic analysis of the non-structural 3A and 3B protein-coding regions of foot-and-mouth disease virus subtype A Iran 05

The A Iran 05 foot-and-mouth disease virus (FMDV) subtype was detected in Iran during 2005 and has proven to be highly virulent. This study was undertaken to focus on molecular and phylogenetic analysis of 3A and 3B coding-regions in the A Iran 05 field isolate. To assess the genetic relatedness of A Iran 05 isolate the nucleotide and predicted amino acid sequences of the 3AB region of type A FMDV isolates were compared with twenty previously described type A FMDV isolates. The phylogenetic tree based on the 672 bp 3AB gene sequences of type A FMDV from thirteen different locations clustered them into five distinct lineages. The A Iran 05 isolate clustered in lineage A along with four type A variants and was closely matched with viruses isolated in Turkey and Pakistan during 2005~2006. The number of protein sequence differences exhibited by each of the isolates revealed that A Iran 05 isolate contains three amino acid substitutions at positions 47 and 119 of 3A and 27 of the 3B coding region. The nucleotide identity between A Iran 05 and the other four isolates of lineage A was estimated to be 98%.     

乙酸钠对油酸诱导的BRL-3A细胞脂肪变性的影响及机制分析

通过向油酸诱导的大鼠肝成纤维细胞(BRL-3A)脂肪变性模型中添加不同浓度(2、4、8 mmol·L^-1)的乙酸钠,探讨其对脂肪变性细胞模型脂代谢的调控机理及细胞损伤的修复作用。试验方法：1)用不同浓度的油酸(0、0.03、0.06、0.12、0.24、0.48) mmol·L^-1刺激BRL-3A细胞24 h后,分别检测细胞相对活力、总脂滴面积、三酰甘油(TG)含量、天门冬氨酸氨基转移酶(AST)及丙氨酸氨基转移酶(ALT)活性,建立脂肪变性细胞模型;2)向BRL-3A细胞中添加不同浓度的乙酸钠,通过流式细胞术检测细胞凋亡率;3)用不同浓度的乙酸钠和0.12 mmol·L^-1油酸共同孵育BRL-3A细胞,试验分为4组,分别为油酸处理组、2 mmol·L^-1乙酸钠+油酸处理组、4 mmol·L^-1乙酸钠+油酸处理组和8 mmol·L^-1乙酸钠+油酸处理组,分别对细胞脂滴、TG含量、AST、ALT活性、AMPK信号通路蛋白以及脂代谢关键基因进行检测。结果显示:1)用0.12 mmol·L^-1油酸处理BRL-3A细胞24 h,成功建立BRL-3A细胞脂肪变性模型。2)不同浓度的乙酸钠对BRL-3A细胞凋亡率没有影响;3)4、8 mmol·L^-1乙酸钠处理脂肪变性细胞模型后,与油酸处理组相比,细胞总脂滴面积、每平方毫米脂滴数、TG含量、AST和ALT活性均显著(P<0.05)或极显著(P<0.01)下降,P-AMPK表达水平显著(P<0.05)或极显著(P<0.01)上升;脂合成代谢相关基因ACC、FAS以及SCD-1 mRNA表达水平均有一定程度下降;脂分解代谢相关基因CPT-1、CPT-2以及ACO mRNA表达水平均有一定程度上升。本研究表明,乙酸钠会通过AMPK通路激活脂分解代谢,减轻肝细胞脂质蓄积,并且对油酸诱导的BRL-3A细胞脂肪变性模型的损伤具有一定缓解作用。     

巴氏杀菌牛乳中免疫球蛋白G含量和乳过氧化物酶活性

免疫球蛋白G和乳过氧化物酶是牛乳中2 种生物活性物质,研究在巴氏杀菌牛乳加工过程中及货架期内的免疫球蛋白G含量和乳过氧化物酶活性变化。结果表明：采用65 ℃以下的均质温度及15～25 MPa的均质压力处理牛乳对2 种生物活性物质影响较小;72～76 ℃、15 s处理可更好地保留2 种生物活性物质;采用膜滤除菌方式比一般巴氏杀菌效果更佳。巴氏杀菌牛乳中的免疫球蛋白G含量和乳过氧化物酶活性不会随着保存时间的延长而显著降低,但采用透明包装的产品长期暴露在光照下会造成乳过氧化物酶部分失活。     

Prevalence of Mycobacterium avium subspecies paratuberculosis (MAP) infection in suspected diarrhoeic buffaloes and cattle reporting at Veterinary University in India

Murrah buffaloes, best breed for milk production are native of Haryana state. They contributes significantly to the farmer’s income, livelihood and food (milk and meat) security, in the semi-tropical regions of North India. Johne’s disease though endemic in the domestic livestock of the country, but reports are not available in the buffaloes suffering from morbidity due to progressive weakness and diarrhoea. We estimated the status of JD in diarrhoeic buffaloes and cattle reporting at Veterinary Clinical Complex of Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar, Haryana, India, using conventional, serological and PCR assays.141 buffaloes suffering from chronic diarrhoea were screened to estimate sero-prevalence of MAP and 50.0 % young and 53.52 % adult animals were positive. Of 14 cattle screened, none of the young and 66.6 % adult cows were positive. In buffaloes, 66.1 and 6.77 %, fecal samples were positive in microscopy and IS900 PCR, respectively. Sero-prevalence of JD was very high in diarrhoeic buffaloes and cattle from Haryana state of India.Buffaloes positive for Mycobacterium avium subspecies paratuberculosis (MAP) infection had reduced total leukocyte count and lymphocytes.     

IBDV野毒株主要结构蛋白基因RT─PCR方法的建立

借助计算机软件，在分析比较了９个传染性法氏囊病病毒（ＩＢＤＶ）Ａ片段结构蛋白基因的基础上，设计并合成了２对ＶＰ２和ＶＰ３基因ＰＣＲ引物，经ＲＴ－ＰＣＲ反应条件优化选择，成功地建立了ＲＴ－ＰＣＲ方法，用于扩增ＩＢＤＶＶＰ２和ＶＰ３基因，经琼脂糖凝胶电泳和分子杂交鉴定，获得４个ＩＢＤＶ野毒株ＶＰ２和ＶＰ３基因，为ＩＢＤＶ分子生物学研究奠定了基础     

牦牛、犏牛睾丸组织中SYCP 3基因mRNA表达水平研究

本文采用RT-PCR和荧光定量PCR对牦牛SYCP3基因的组织表达,以及SYCP3基因在牦牛和犏牛睾丸组织中的表达水平进行分析。结果表明,SYCP3基因在牦牛睾丸组织中特异表达,牦牛与犏牛睾丸组织中SYCP3基因的表达水平差异极显著（P〈0．01）。睾丸和附睾组织切片显示,牦牛睾丸组织中可见各级生精细胞,附睾内可见发育良好的精子,而犏牛睾丸组织中无次级精母细胞和更高级生精细胞、附睾内未观测到精子,与人和小鼠SY-CP3基因缺失或表达水平降低出现的表型一致,可以认为SYCP3基因的表达水平可能与犏牛的雄性不育有一定的关系。     

猪粪中除臭微生物的筛选和鉴定

用感官法初筛出20株菌株,再通过定性复筛试验,最后从猪粪便中共分离出5株除臭微生物,都具有很强的除臭效果,其中假单孢菌属(ZY-1)氨气的去除率高达47.70%,巴氏芽孢杆菌(WJ-2)硫化氢的去除率高达62.5%,显示出这类细菌在猪场粪便的处理过程中具有良好的应用前景。     

猪流行性腹泻病毒ORF3和M基因的克隆与序列分析

为了解福建省猪流行性腹泻病毒(Porcine epidemic diarrhea virus,PEDV)毒株ORF3和M基因变异情况,本研究从4个不同规模猪场发生仔猪“顽固性腹泻”疾病的病料中扩增到4株PEDV的ORF3和M基因,并进行了序列分析.结果表明:4株PEDV ORF3基因均含有675个碱基,编码224个氨基酸,与GenBank中登录的代表性PEDV核苷酸的同源性为89.7％～100.0％,氨基酸的同源性为94.7％～99.6％,其中FJPT毒株核苷酸的同源性与CV777 truncated毒株最低,仅为89.7％,FJNP毒株核苷酸的同源性与中国北方流行的CH ZKFG 11毒株最高,达100.0％.M基因含有681个碱基,编码226个氨基酸,与GenBank中登录的代表性PEDV核苷酸的同源性为94.8％～100.0％,氨基酸的同源性为94.8％～99.6％,其中FJPT毒株核苷酸的同源性与日本D89752毒株最低,仅为94.8％,FJNP毒株核苷酸的同源性与韩国CPF193、泰国毒株最高,达100.0％.4株PEDV毒株均与国内外流行强毒株的亲缘关系较近,与attenuate DR13弱毒株的亲缘关系较远.