三种益生菌联合固态发酵提高豆粕中的粗蛋白含量研究

采用三种益生菌菌联合固态发酵法以生产出高蛋白含量的豆粕。实验探讨了菌液接种量、发酵温度、发酵时间和料水比对发酵豆粕粗蛋白质含量的影响,得出高含量粗蛋白质豆粕的最佳生产工艺。正交试验表明,三种益生菌联合固态发酵法的最适条件为:菌液量300∶1、发酵温度32℃、料水比为1∶1. 1和发酵时间72 h。发酵豆粕的粗蛋白质含量为53. 06 g/(100 g),比发酵前提高9. 51%。     

石斑鱼配合饲料中发酵豆粕和豆粕部分替代白鱼粉的研究

在浮式海水网箱(1.5m×1m×1.5m)中养殖石斑鱼幼鱼(9.4±0.1g),在等氮(52% CP)基础上进行以发酵豆粕和普通豆粕替代鱼粉的实验, 为期56天.结果显示在石斑鱼饲料中添加14%发酵豆粕,其增重率、特定生长率(SGR)、饲料效率和蛋白质效率与对照组没有显著性差异(P>0.05),以后随着发酵豆粕添加量的上升,这些指标都显著下降(P<0.05).在同样替代水平下,添加21%发酵豆粕组,增重率,SGR,饲料效率和蛋白质效率都比添加20%豆粕组高(P<0.05),表明对海水肉食性鱼类来说,发酵豆粕是一种比豆粕更优良的蛋白源.用折线模型分析增重率随白鱼粉替代水平的变化关系,结果表明在石斑鱼配合饲料中,发酵豆粕替代白鱼粉的最适量为10%.从实际生产的经济效益出发,建议在饲料中添加14%发酵豆粕,对石斑鱼的生长和鱼体组成不会造成显著影响.     

发酵豆粕饲料对异育银鲫非特异性免疫功能的影响

经微生物混菌发酵的豆粕与未经发酵的豆粕依不同比例混合, 按 30 0%的比例添加在某种市售鲫鱼饲料中, 连续投喂异育银鲫 (Carassiusauratusgibelio) 30d后, 通过测定供试鱼的增重量、血清中溶菌酶活性、谷丙转氨酶活性 (SGPT)、血清总蛋白含量和白细胞吞噬活性, 比较不同添加量的发酵豆粕对异育银鲫非特异性免疫功能的影响。结果表明, 随着饲料中发酵豆粕添加量的上升, 供试异育银鲫不仅增重量有所提高, 各项非特异性免疫指标也有所改善, SGPT的活性出现下降趋势。与未经过发酵的豆粕相比, 发酵豆粕具有一定的促进生长、增强非特异性免疫功能和改善肝功能的作用。     

发酵豆粕替代鱼粉对凡纳滨对虾生长、免疫相关酶及免疫相关基因表达的影响

从免疫相关酶活及基因转录水平角度探讨发酵豆粕替代鱼粉对凡纳滨对虾健康生长及免疫机能机制的影响。实验设置5种实用饲料,以30%鱼粉组(FM)为对照组,分别用4%(FSM4)、8%(FSM8)、12%(FSM12)和16%(FSM16)的发酵豆粕,替代9.7%、19.4%、29.1%和38.8%鱼粉,分为4个处理组,饲养体质量为(7.62±0.23)g的凡纳滨对虾60 d后,统计生长性能,检测肌肉营养成分、血清及肝胰腺免疫相关酶活性,肝胰腺HSP70和鳃Toll受体、IMD、溶菌酶(LZM)免疫相关基因m RNA的表达水平。结果显示:(1)与对照组相比,发酵豆粕替代鱼粉对凡纳滨对虾成活率无显著影响;过低或过高水平的发酵豆粕替代鱼粉皆会影响凡纳滨对虾的特定生长率。(2)除FSM12组外,肌肉粗蛋白含量发酵豆粕替代组均低于对照组;粗脂肪含量随着发酵豆粕替代量的升高而降低,FSM16组最低。(3)血清谷丙转氨酶活FSM4和FSM16组显著高于对照组;谷草转氨酶活FSM4组最高,而FSM8组最低;除FSM12组外;碱性磷酸酶活性发酵豆粕替代组显著高于对照组;除FSM16组外,血清总蛋白与肝胰腺丙二醛含量发酵豆粕替代组与对照组无显著性差异。(4)随着发酵豆粕替代量增加,鳃Toll受体m RNA表达呈上升趋势,鳃IMD m RNA表达则呈先升后降趋势,发酵豆粕替代比例过高会降低鳃LZM m RNA表达水平,而肝胰腺HSP70 m RNA表达量则随着发酵豆粕替代比例增加呈上升趋势。综上所述,发酵豆粕适量替代鱼粉对凡纳滨对虾生长性能无显著影响,并可提高免疫相关酶活,改变免疫相关基因的表达。本实验条件下适宜发酵豆粕用量为8%~12%;替代量过高,会引起机体的过度应激。     

发酵豆粕替代鱼粉对斑点叉尾生长和饲料表观消化率的影响

以发酵豆粕25%、50%、75%和100%的比例分别等量替代基础日粮中的鱼粉,研究了发酵豆粕对斑点叉尾(Ictalurus punctatus)生长和饲料表观消化率的影响。结果显示:以25%～75%的发酵豆粕替代鱼粉时,斑点叉尾增重率、特定生长率、饲料干物质和粗蛋白的表观消化率比对照组稍高(P>0.05),饲料系数与对照组没有显著性差异(P>0.05);而以发酵豆粕100%的比例替代鱼粉时,上述5种指标与对照组无显著性差异。结果表明,斑点叉尾日粮中发酵豆粕可以100%替代鱼粉,其中以25%的比例替代效果更佳。     

发酵豆粕和酶解鱼粉对刺参免疫力的影响

研究在饲料中按一定比例添加发酵豆粕和酶解鱼粉对刺参幼苗(Apostichopus japonicus)酸性磷酸酶(ACP)、碱性磷酸酶(AKP)、溶菌酶(LSZ)、超氧化物歧化酶(SOD)活性的影响。于投喂后第60d后检测ACP、AKP、LSZ与SOD活性。结果显示,总体上分析用发酵豆粕替代豆粕比用酶解鱼粉替代鱼粉对刺参幼苗ACP、AKP的影响要显著。单独分析单一因素,各添加组ACP、AKP活性较不添加组均有不同程度的升高,其中用发酵豆粕替代100%大豆粕组与用酶解鱼粉替代50%鱼粉组效果最佳。发酵豆粕组与酶解鱼粉组对LSZ活性的影响没有显著差异。其发酵豆粕各个替代组较不替代组LSZ的活力都有不同程度的升高,其中替代75%组最为明显(P0.05)。酶解鱼粉各个替代组较不替代组也有不同程度的升高,但差异不显著。总体上分析发酵豆粕组与酶解鱼粉组对SOD活性的影响没有显著差异。两者不同替代组较不替代组SOD的活性都有不同程度的升高,但都不显著。研究表明发酵豆粕和酶解鱼粉替代饲料中的大豆粕和鱼粉对刺参幼参的免疫力都有不同程度增强作用。     

豆粕的坚强芽孢杆菌(Bacillus firmus)发酵工艺优化及其营养成分分析

坚强芽孢杆菌(Bacillus firmus) PC024是一株分离自中国明对虾(Fenneropenaeus chinensis)养殖环境,且能够提高对虾免疫力和抗病力的益生菌.本研究优化其发酵豆粕的工艺条件,单因素优化结果:最佳接种量为2× 106 CFU/g,最佳料水比为1∶0.8,最佳发酵时间为90 h,最佳发酵温度为37℃.在单因素实验结果的基础上,采用响应面法对4个因素进行了优化,最终确定最佳发酵条件:发酵温度为39.0℃,发酵时间为100 h 18 min,料水比为1∶0.96,接种量为3.84× 106 CFU/g.经此条件发酵后,发酵产物中的菌浓度可达1.23×1010 CFU/g,验证值与预测值相差5.13％,优化模型可靠.豆粕经发酵后发生感官变化,豆粕发酵的得率为(93.89±0.01)％,可溶性蛋白含量由发酵前的(39.16±0.01)％增加到(58.80±4.54)％,豆粕粗蛋白质由发酵前的50.71％增加到55.03％,15种氨基酸的总含量增加到原来的132.30％,增加比例最大的5种为精氨酸(168.60％)、赖氨酸(157.20％)、丝氨酸(152.50％)、苏氨酸(139.04％)和甘氨酸(138.40％).经SDS-PAGE显示,蛋白大分子得到有效降解.本研究可为益生菌的利用和对虾疾病防控提供新思路.     

杂交罗非鱼饲料中豆粕、发酵豆粕和晶体氨基酸替代鱼粉的研究

添加豆粕(soybean meal,SBM)、发酵豆粕(fermented soybean meal,FSBM)和晶体氨基酸(crystalline amino acid,CAA)替代杂交罗非鱼(Oreoehromis niloticus ♀×O.aureus ♂)实用饲料中5%的鱼粉,连续投喂初始体重为9.41±0.05 g的罗非鱼9周后,通过测定罗非鱼的增重率(WGR,%)、特定生长率(SGR,%)、饲料效率(FE,%)、蛋白质效率(PER,%),并进行肝脏分析和血浆分析,比较各组饲料对罗非鱼生长和非特异性免疫的影响.结果表明,发酵豆粕+晶体氨基酸组的WGR、SGR高于其他3组,鱼粉组的FE高于其他3组;PER方面各组间差异不显著,4组饲料对罗非鱼肝脏组成、血浆成分和存活率没有造成显著差异.     

发酵豆渣对哺乳母猪生产性能的影响

为研究哺乳母猪饲料中添加发酵豆渣对哺乳母猪生产性能的影响,试验在江苏泰州一规模化猪场选取10头哺乳母猪进行发酵豆渣替代部分豆粕和麸皮饲养试验。结果表明,日粮添加5%的发酵豆渣提高了母猪泌乳期日均采食量;在哺乳期24 d时,发酵豆渣组仔猪存活率比对照组高32%;在哺乳期27 d时,发酵豆渣组仔猪平均体增重增加。母猪泌乳量和仔猪窝重在哺乳期24 d和27 d无显著差异。泌乳期日粮添加5%的发酵豆渣改善了饲料的适口性,增加了母猪采食量,提高了仔猪存活率,使母猪产后体况恢复良好。     

发酵豆粕替代鱼粉对斑点叉尾鮰消化酶活性的影响

以发酵豆粕替代基础日粮中25%、50%、75%和100%的鱼粉,饲养平均体重为1.1g的斑点叉尾鮰42d后,研究了发酵豆粕对斑点叉尾鮰生长和消化酶活性的影响.结果显示:发酵豆粕替代25%、50%、75%鱼粉组斑点叉尾鮰增重率、特定生长率比对照组稍高(P>0.05),饲料系数与对照组没有显著性差异(P>0.05);替代100%的鱼粉时,这些指标与对照组也没有显著性差异;试验组斑点叉尾鮰胃蛋白酶活性与对照组无显著性差异(P>0.05);肝胰脏和肠道的蛋白酶活性随着替代比例的提高而呈不明显的上升趋势(P>0.05);各试验组鱼淀粉酶活性均高于对照组,其中以替代50%鱼粉组最高,但差异不显著(P>0.05).     

Nitrification kinetics of biofilm as affected by water quality factors

Various types of fixed film biofilters have been used in recirculating aquaculture systems under different water quality and operating conditions. The effectiveness of the nitrification process can be evaluated by nitrification kinetics. Nitrification in the bacterial film of the biofilter involves physical, chemical and biological processes that are governed by a variety of parameters such as substrate and dissolved oxygen concentrations, organic matters, temperature, pH, alkalinity, salinity and turbulence level. The impacts of these parameters upon nitrification kinetics make predicting the performance of a biofilter for a given application an engineering challenge. Knowing the performance of a biofilter is critical for both designers and managers. This paper summarizes the current knowledge on nitrification kinetics as affected by the aforementioned factors based on literature and the results from the authors’ laboratories. These factors were ranked according to their significance of impact on biofilter nitrification performance. The information presented can be used as a reference for the design and operation of biofilters in recirculating aquaculture systems.     

Selection of taxa as indicators of river and freshwater wetland quality in the UK

• 1. To assess the efficacy of environmental management policies and practices, there is a progressive transition from monitoring of activities towards assessment of their outcomes for the environment.
• 2. Population trends of key taxonomic groups can serve as useful indicators of broader environmental integrity and health. Several necessary and desirable criteria for selecting meaningful and suitable indicators are discussed. The attributes of a range of taxa and survey methods used for their assessment are discussed with reference to these criteria.
• 3. Survey methods, data holdings and analytical methods for populations of wild birds at present provide a good basis for developing indicators of the quality of fresh waters at a landscape scale. Other taxa are not necessarily any less appropriate; however, survey design and data representativeness are often limiting factors to the use of other taxa for assessing geographic and temporal trends.
• 4. Taxonomic science and ecological monitoring are necessary for determining society' progress with sustainable development and for informing appropriate enhancements to policy and management practice, particularly so for fresh waters.

Copyright © 2007 John Wiley & Sons, Ltd.     

Fish welfare and quality as affected by pre-slaughter and slaughter management

. A reliable assessment of animal welfare-suffering and of its impact on product quality requires a multidisciplinary approach that takes into account fish behaviour and the different biochemical and physiological processes involved. This might be done by the contemporary study of changes of indicators of brain function, endocrine responses, post mortem tissue biochemical processes and quality changes. This work reviewed some of the most used indices of stress at the time of slaughter, commercial slaughter methods and related stress effects on physical and biochemical parameters of fish quality. The set of the available data seemed to indicate that, although of some results appear contradictory, pre-slaughter and slaughter stressful practices could have an important effect on the flesh quality in fish. A clear effect emerged mostly on the physical properties of flesh, because severe stress at slaughter time exhausted muscular energies, produced more lactic acid, reduced muscular pH, increased the rate of rigor mortis onset. In this way they could have significant negative effects on technological traits, flesh quality and keeping quality of fish. Asphyxia and electrically stunned fish were more stressed than spiked, knocked and live chilled fish. Combining various methods together might be a more satisfactory strategy for both animal welfare and product quality.     

Maturational factors as indicators of egg quality in Japanese eel, Anguilla japonica

In order to identify maturational factors that can serve as indicators of egg quality in artificially matured Japanese eel, Anguilla japonica, maturation-promoting factor (MPF; consists of cdc2 and cyclin B) related proteins and chromosomes were examined. Mitogen-activated protein kinase (MAPK; 44 kDa band) and cdc2 (35 kDa and 34 kDa band) were detected. Chromosomes aligned on a vertical spindle appeared normal; however, chromosomes on a horizontal spindle and dispersed chromosomes seemed unusual.     

真空包装淡腌青鱼品质和细菌类型及数量

在零售市场和生产企业抽取4批真空包装淡腌青鱼,对其感官、化学和细菌学品质特性进行分析,并对细菌类型和数量进行研究。结果显示,产品栅栏因子及强度存在差异,盐分含量6.68%~12.06%,平均值(9.36±2.2)%;水分活度值0.75~0.91,平均值0.82±0.07;pH值6.00~6.30,平均值6.20±0.13。栅栏因子种类和强度的不同决定产品品质的差异,感官评价均可接受,过氧化值均值为19.65±8.75 meq/kg,挥发性盐基氮均值为24.50±15.30 mg/100 g,菌落总数均值为4.45±1.15 cfu/g,大肠菌群均低于30 MPN/100 g。从4批淡腌青鱼样品分离到234株细菌,73.9%是革兰氏阳性细菌,其中36.3%是葡萄球菌,31.6%是链球菌,并出现少量微球菌和棒状杆菌;由需氧革兰氏阴性杆菌不动杆菌、摩氏杆菌和鞘氨醇单胞菌组成较小的细菌菌群约占总细菌群落的18.4%,显示水分活度、盐分含量和pH值等栅栏因子与产品细菌类型和数量呈一定相关性。     

Improvement of copepod nutritional quality as live food for aquaculture: a review

In hatchery, an adequate supply of live food for first‐feeding fish larvae is essential and nutritional quality of live food organisms can be improved through nutrient enrichment. The use of live food organisms, especially at first feeding, is a requisite for most marine fish larvae. In ocean, marine fish larvae primarily feed on copepods, but the production protocols of copepods as live food is underdeveloped in hatchery. As the food ingestion and the digestive system of copepods are different from other live food organisms (e.g. rotifers), the nutrition enrichment procedures with emulsion oil used in rotifers is not effective on copepods. This review focuses on alteration of nutrient composition of copepods through manipulation of copepod food before they are fed to fish larvae. Specifically, we discuss the relationship between the changes of fatty acid compositions in dietary algae and in copepods. The review links nutrient supply to copepods and the change of nutrition in copepods and suggests ways to improve copepod nutrition in hatcheries.     

优质牧草对提高草鱼品质的研究

牧草占总投饵量60%、配合饲料占总投饵量40%的条件下,养殖的草鱼与全配合饲料养殖的草鱼在肥满度、内脏比、肠脂比、躯壳比、比肠长等多项指标的对比中,都表现为差异显著(P<0.05);特别是后者的肠脂比为4.46%,是前者1.42%的3.14倍。后者鱼肉中脂肪含量为3.70%,是前者1.00%的3.70倍(P<0.05)。说明草食性鱼类的养殖中,大比例提高人工牧草在饲料中的比重,有助于降低鱼肉的脂肪含量,提高鱼肉氨基酸水平,从而达到改善口感、增加鲜味、提高鱼肉品质的目的。     

Standardized method for the Holmen pellet tester (NHP100) as a tool for evaluating the physical quality of fish feed

The fish feed production industry requires reliable methods measuring the physical quality of feed before it is being released to the customer. The Holmen pellet tester (NHP 100) could be adapted for this purpose, but the special characteristics of fish feed require particular care during testing. The aim of the study was to determine the standardized conditions for using the Holmen tester as a tool measuring the durability of fish feed. Screening tests were performed on commercial fish feed samples to assess the effects of temperature, pressure and cleaning the instrument between runs. The operating pressure was found to be the most important factor that can influence the results. The temperature of the operating air can also alter the results; increased temperatures can cause oil to melt and leak from the pellets. Cleaning the instrument between analyses can also affect the results. This study shows that when these factors are maintained at a standardized level, the Holmen pellet tester is a valuable tool for assessing the physical quality of fish feed giving additional information on the quality of feed pellets compared to other durability tests like DORIS.