双低菜籽粕对草鱼和鲤甲状腺、肝、肾组织结构的影响

以组织学方法,研究了投喂不同含量双低菜籽粕对草鱼和鲤甲状腺、肝、肾组织的影响。结果表明:在试验的前28 d,双低菜籽粕各不同含量的日粮(17%、34%、51%、68%)对草鱼甲状腺、肝脏组织没有影响,但菜籽粕含量为68%的试验组草鱼肾小管上皮出现颗粒变性。第42天后,菜籽粕含量为68%的试验组草鱼甲状腺滤泡上皮轻度增生,滤泡结构不规则;菜籽粕含量等于或大于51%的试验组草鱼肝脏出现颗粒变性和空泡变性,肾小球有透明变性,肾脏轻度淤血。在试验的第28天,双低菜籽粕含量等于或大于52.2%的试验组鲤甲状腺滤泡上皮细胞的高度增加,肝细胞空泡变性,有轻微的肾小球透明变性。第42天后菜籽粕含量等于或大于34.8%的试验组鲤甲状腺滤泡上皮细胞的高度增加,滤泡胶质的边缘出现缺刻;肝脏出现淤血,部分肝细胞坏死;肾小球透明变性,肾脏淤血。     

饲料中胆汁酸对红鳍东方鲀脂肪酸组成及抗氧化能力的影响

为研究饲料中添加胆汁酸对红鳍东方鲀脂肪酸组成及抗氧化能力的影响,以鱼油为主要脂肪源,配制五种等氮饲料,以初始体重14g的红鳍东方鲀进行为期56天的投喂养殖实验。设置适宜脂肪含量(8%)的对照组,并在对照组添加0.02%及0.10%的胆汁酸,分别获得低胆汁酸添加组(BA)和高胆汁酸组(HBA)。另设一高脂组(脂肪含量12.5%,HL组)及高脂+0.02%胆汁酸组(HLBA组)。结果表明,添加胆汁酸的处理组肌肉和肝脏MUFA均低于对照组,其中HBA组显著低于对照组(P<0.05)。肌肉中n-6PUFA含量在HLBA和HL组显著低于其他组(P<0.05)。在适宜脂肪含量的三个处理组间,肝脏中的C20:0、C16:1n-7、C18:1n-9、C18:2n-6、C20:4n-6、C18:3n-3、C18:4n-3、C20:5n-3和C22:6n-3都呈现随着胆汁酸添加量增加而降低的趋势。血清超氧化物歧化酶活性和谷胱甘肽过氧化物酶活性都有随着胆汁酸添加而升高的趋势,且在高脂组显著高于对照组(P<0.05);血清谷胱甘肽还原酶则呈现相反的趋势。肝脏中谷胱甘肽过氧化物酶1的mRNA相对表达量在对照组显著高于其他组,而BA组氧化还原酶1的基因表达量显著高于对照组;在高脂组添加胆汁酸显著升高了过氧化氢酶的基因表达量。综上所述,饲料中胆汁酸的添加降低了饲料及鱼体组织中一系列长链脂肪酸的含量;胆汁酸对血清抗氧化蛋白活性的影响与其对肝脏抗氧化相关基因表达的影响结果不一致。     

不同处理对蛭石栽培的微型薯疮痂病防控效果及其微生态效应分析

通过田间小区试验评价了6个不同处理对蛭石栽培的微型马铃薯疮痂病的防效,并采用16S核糖体基因高通量测序技术研究了蛭石中细菌群落结构的变化.试验结果显示,棉隆+青霉菌34107处理对疮痂病防效最好(93.43％),显著高于对照药剂中生菌素处理(65.10％);而且商品薯的数量和经济效益也最高,分别达到348.3万个/hm...     

猪源发酵乳杆菌的筛选及其潜在益生性能

【目的】对从健康仔猪粪便中筛选分离出一株发酵乳杆菌的益生性能进行测试,为其在畜禽动物养殖中的应用提供参考。【方法】采用Rogosa SL完全选择性培养基分离出106株乳酸菌,通过革兰氏染色、酸和胆盐耐受初步筛选出1株潜在的饲用乳酸菌,经16S rDNA序列鉴定为发酵乳杆菌LF1,并对其益生性能潜力进行评估,包括抑菌活性(针对大肠杆菌K88、金黄色葡萄球菌、猪链球菌、沙门氏菌以及弧菌等12种病原菌)、对模拟胃液中酸性环境的耐受性、对胆盐的耐受性以及对小肠上皮细胞的粘附性。【结果】发酵乳杆菌LF1耐酸和耐胆盐的能力较强,显示出较强的益生菌潜力,但LF1菌株对猪肠道上皮细胞的粘附能力不强。在生物拮抗作用方面,发酵乳杆菌LF1的培养上清可以显著抑制多种常见动物病原菌生长。【结论】发酵乳杆菌LF1具有较好的益生性能,通过进一步的动物实验评估后,可以作为应用于畜禽养殖业的益生菌候选菌株。     

两种鲤鲫杂交回交子代染色体核型分析及比较

采用PHA和秋水仙素体内注射制备两种鲤鲫杂交回交子代鱼（鲤鲫杂交♀×德国镜鲤♂;鲤鲫杂交♀×鲤♂）的染色体。结果表明：两种鲤鲫杂交回交子代染色体组由150条染色体组成,按着丝粒位置染色体组型可分为四组,每个染色体小组均由三条同源染色体组成。其中鲤鲫杂交♀×鲤♂回交的染色体数目为3n=150,染色体臂数NF=234,其核型公式为：3n=60m＋24sin＋36st＋30t;鲤鲫杂交♀×德国镜鲤♂回交染色体数目为3n=150,染色体臂数NF=258,其核型公式为：3n=63m＋45sin＋12st＋30t。     

A comparison of fatty acid composition and quality aspects of eggs and larvae from cultured and wild broodstock of common sole (Solea solea L.)

Eggs from a F₁ cultured broodstock of sole were compared with eggs from wild‐caught breeders throughout one spawning season, to evaluate if egg quality may be affected by culture‐related conditions. Fourteen batches of eggs from cultured broodstock and 17 batches from wild‐caught sole were compared with respect to fatty acid (FA) composition, egg size, fertilization rate and hatching rate. Based on a multivariate analysis of the FA profiles, it was possible to discriminate between culture and wild inheritance. Eggs from cultured broodstock had high levels of C20:1(n‐9), C18:2(n‐6) and C18:3(n‐3), whereas eggs from wild fish had high levels of C16:1(n‐7), C20:4(n‐6) and C20:5(n‐3). Differences in FA profiles were most likely related to dietary differences. Fertilization and hatching rates were generally low and lowest in eggs from cultured broodstock, but not related to FA composition. Larval growth of one batch from each group was compared. Larval growth was not correlated to broodstock origin, FA composition or egg or larval size. However, larval survival was significantly lower for larvae from cultured broodstock.     

Preliminary study to evaluate the effects of dietary bile acids on growth performance and lipid metabolism of juvenile genetically improved farmed tilapia (Oreochromis niloticus) fed plant ingredient‐based diets

A 9‐week feeding experiment was conducted to investigate the effects of dietary bile acids (BAs) on juvenile genetically improved farmed tilapia (GIFT) (Oreochromis niloticus) based on the evaluations of growth performance and parameters relevant to lipid metabolism. Each of five vegetable protein‐based diets containing BAs at a level of 0, 0.05, 0.15, 0.45 or 1.35 g/kg diet was fed to three replicates with 40 fish (8.2 g per fish). The results showed that weight gain (WG) increased significantly with the increase in BAs from 0 to 0.15 g/kg diet and then decreased significantly at a higher BA supplementation. Dietary BAs significantly reduced the crude lipid content in the whole body, muscle and liver tissue of GIFT. Fish fed diet with 1.35 g BAs/kg diet developed serious nuclear migration and vacuolization in hepatocytes. Gall bladder appeared to contain white solid and has fragile capsules. Dietary BA supplementation had significant effects on serum biochemical indices and activities of lipid metabolism enzymes in liver and intestine. In conclusion, dietary bile acid supplementation (0.15 g/kg) can facilitate the lipid metabolism and therefore promote the growth of tilapia. However, overdosed dietary BAs induced gallstone development, disrupted lipid metabolism and depressed the growth performances of GIFT.     

Effects of antimicrobial peptides on growth,morphology of foregut villi and related genes mRNA expression in the common carp (Cyprinus carpio)

A 60‐day feeding trial was conducted to examine the effects of different levels (0, 100, 200, 400 and 600 mg/kg) of antimicrobial peptides on growth, protease activity of foregut, the morphology of foregut villi and related genes mRNA expression level in the common carp (Cyprinus carpio). The results showed that the feed of antimicrobial peptides promote common carp growth, and the optimal dosage of antimicrobial peptides is 200–333 mg/kg in the common carp feed. The protease activity of 200 and 400 mg/kg groups were significantly higher than the control and other groups (p < 0.05). The foregut villus height with 100, 200 and 400 mg/kg antimicrobial peptide groups were significantly higher than control group (p < 0.05). The crypt depth of 200 and 400 mg/kg antimicrobial peptide groups were significantly lower than control group (p < 0.05). The ratio of villus height and crypt depth of 100, 200 and 400 mg/kg antimicrobial peptide groups were significantly higher than control group (p < 0.05). The ratio with 600 mg/kg group was significantly lower than the control group (p < 0.05). The IGF‐I gene expression level of 200 mg/kg and 400 mg/kg groups were significantly higher than the control group and 600 mg/kg group (p < 0.05). The IL‐1β gene expression level of 100 mg/kg and 200 mg/kg groups were significantly higher than the control group (p < 0.05). These results indicated up‐regulation of growth and immune related genes in antimicrobial peptides fed common carp. Correlation analysis showed that IGF‐I mRNA and IL‐1β mRNA were positively correlated with SGR. IL‐1β mRNA and FCR were significantly negative correlated. It indicated that growth and immune gene common regulated the growth of the carp under antimicrobial peptides intervention. In conclusion, antimicrobial peptides can improve growth and related genes mRNA expression in the common carp. Further studies using molecular biological technique or immunologic methods are required to conclude that antimicrobial peptides are beneficial in common carp.     

鲤鱼血淋巴细胞培养及染色体制备条件探索

从鲤鱼侧线鳞处静脉采血于含有肝素的一次性注射器中，采用RPMI1640全培养基进行体外淋巴细胞培养。通过对采血后细胞培养时间、秋水仙素浓度及加入时间、低渗时间及温度等条件的摸索，建立了较成熟的培养鱼类血淋巴细胞的实验方法。     

利用GoldenGate分析的高通量SNP芯片对鲤基因进行分型

单核苷酸多态性(SNPs)标记在大多数物种基因组中数量巨大且分布均匀,是许多水产物种遗传研究的理想标记,因此快速发展了几种高通量、快速的SNP标记分型平台。本研究利用Golden Gate分析技术对鲤Cyprinus carpio转录组测序的1 536个SNP标记合成了一张中等密度SNP芯片,对5个鲤群体的480份样本进行基因分型。结果表明:1 235个SNP标记成功分型,约占80%;915个标记至少在一个家系中呈现多态性,占74.1%;标记最小等位基因频率(MAF)介于0.05~0.5之间,平均为0.334,其中48.9%的标记最小等位基因频率(MAF)大于平均值;5个群体中SNP标记平均多态性信息含量(PIC)在0.3左右,为中度多态,杂合度为0.010~0.990,平均为0.5左右,暗示群体具有丰富的遗传多态性,育种价值及性状改良潜力很大。本研究分型的多态性SNP标记可广泛应用于遗传多样性研究、标记-性状关联分析以及分子标记辅助育种。