两种加州鲈饲料的养殖效果

加州鲈又名大口黑鲈,为肉食性温水鱼类,原产于北美洲的江河湖泊中。因其肉质鲜美、生长快,经济价值高而受到广大养殖者的青睐,目前,已经在很多国家和地区进行养殖（包括中国台湾和大陆）。加州鲈系偏肉食性鱼类,国内对其营养需求的研究很少,传统的养殖喂养加州鲈的...     

不同养殖模式下加州鲈营养成分差异分析

为了解池塘养殖和工厂化循环水养殖加州鲈营养品质差异,采用国家标准方法测定了两种不同养殖模式加州鲈(Micropterus salmoides)肌肉的常规营养成分、脂肪酸组分和氨基酸组分,并对两者的营养价值进行了分析评价。结果显示:循环水养殖加州鲈肌肉中灰分、粗脂肪和粗蛋白质含量均高于池塘养殖加州鲈,其中粗蛋白含量达到极显著水平;共检测出10种脂肪酸,循环水养殖加州鲈的总脂肪酸、总多不饱和脂肪酸和EPA+DHA均高于池塘养殖加州鲈,总不饱和脂肪酸和总多不饱和脂肪酸的差异达到极显著水平;共检测出17种氨基酸,循环水养殖加州鲈肌肉中各种必需氨基酸(EAA)含量均高于池塘养殖加州鲈,除苯丙氨酸外差异均达到显著或极显著水平,其中赖氨酸含量最高,亮氨酸次之,蛋氨酸含量最低;循环水养殖加州鲈肌肉的总氨基酸、总必需氨基酸、总非必需氨基酸和总鲜味氨基酸含量均高于池塘养殖加州鲈,前三者差异达到极显著水平;根据ASS和CS评分结果,池塘养殖和循环水养殖加州鲈肌肉中第一、二限制性氨基酸为缬氨酸和蛋+半胱氨酸,循环水养殖加州鲈肌肉中EAA的ASS和CS均大于池塘养殖加州鲈,且数值均大于或接近1。结果表明:工厂化循环水养殖加州鲈肌肉较之池塘养殖加州鲈的营养品质更好,更加符合人类膳食的需要。     

衡水地区加州鲈鱼反季节养殖试验

为探索适合本地区的养殖模式和技术路径,于2019-2020年开展了加州鲈(Micropterus salmoides)反季养殖试验.通过池塘清理与消毒、选择优良苗种、合理确定密度、科学投喂、水质调控和越冬管理等一系列措施,试验取得成功,获得良好经济效益.同时,为在衡水地区推广鲈鱼养殖探索出较为成功的养殖方法和技术路径.     

加州鲈养殖技术总结

加州鲈养殖技术总结姚国成（广东省水产局广州５１０２２２）加州鲈是大口黑鲈的俗称。其适应性强，既可在池塘中混养，也可与其他家鱼混养，还适宜在网箱等小水体中高密度饲养。在广东，开始是在成鱼塘中混养，近年来以池塘主养为多，虽然每年养殖面积约６０００公顷，但...     

七星鲈网箱驯化投喂膨化浮性饲料技术探讨

七星鲈为广温、广盐近海洋浅海中的下层鱼类,适宜在咸淡水中养殖。该鱼肉嫩味美,有“淡水石斑”之称。市场价格高、销路好,经济效益显著。此鱼类为强肉食性,为了能进行大面积推广养殖,避免投喂冰鲜、活鱼而导致养殖水环境污染,根据省科技厅的试验项目安排,我们对七星鲈的食性从     

加州鲈工厂化苗种培育技术

为适应北方地区气候特点和市场需求,利用工厂化循环水系统培育反季节加州鲈苗种,在车间内进行饵料培育收集、水花下水、聚群饲养、饲料驯食、水质管理、筛苗分池等。采用12个培育池(总面积235.5 m²),每池投放水花30万尾,经过40 d培育,共产出59.94万尾苗种,平均成活率约为16.65%。     

膨化浮性饲料在水产养殖中的应用

随着水产养殖业向规模化、集约化、专业化和工厂化的方向发展，对水产饲料的要求也越来越高，传统的粉状配合饲料和颗粒配合饲料存在着水中稳定性差、沉降速度快、易造成饲料散失浪费和水质污染等弊端，已越来越不适应现代水产养殖的需要，而膨化浮性饲料能较好地克服粉状和颗粒饲料的这些弊端，是现代水产养殖的理想饲料品种，有着较好的市场潜力和市场前景。     

豆粕型膨化浮性饲料养殖德国镜鲤试验

沉性硬颗粒饲料是我省目前水产养殖生产应用的主要饲料，而膨化浮性饲料在我省尚未应用于规模化水产养殖生产中。为了探讨膨化浮性饲料在我省水产养殖应用的可行性，2002年，在黑龙江省水产技术推广总站水产试验场，采用豆粕型膨化浮性饲料进行德国镜鲤鱼种养至商品鱼的生长性能和经济效益示范试验，取得了较好的效果。     

北方地区加州鲈亲本越冬培育试验

温棚越冬方式下加州鲈(Micropterus salmoides)亲本的存活率为98%,增重率为25%;雌性亲本性成熟系数(全体重)为5.76%。室外池塘越冬方式下加州鲈亲本的存活率为70%,增重率为5%;雌性亲本性成熟系数(全体重)为2.50%。温棚越冬方式在加州鲈亲本存活率、增重率及性腺发育速度方面具有较大的优势。     

加州鲈高产养殖技术

加州鲈高产养殖技术吕梅良，顾志华（江苏省吴县市水产局）加州鲈具适应性强、性情温驯、生长迅速、病虫害少、容易捕捞、经济效益高等特点，近年来我市养殖规模不断扩大。１９９５年我们在本市黄桥镇水产养殖场进行了加州鲈池塘高产养殖试验，当年取得了良好的收益。现将...     

Evaluation of different starch sources in extruded feed for Atlantic salmon

The aim of the experiment was to investigate the effect of partial or total substitution of wheat flour with oat meal and tapioca starch in extruded salmon feed. A mixture design (simplex centroid mixture design) was used to analyse the effect of starch source on physical quality of extruded feed. Physical quality of the extruded feed was evaluated as cohesiveness, pellet density, axial and radial expansion, durability, hardness, strain at rupture and elastic modulus. Starch sources affected behaviour of the diet formulations during extrusion and caused changes in the physical properties of the extruded products. Significant correlations (P < 0.05) between physical properties and weight fraction of the starch sources allowed the establishment of predictive models. The inclusion of oat meal and tapioca starch in the diet gave extruded feed with a higher porosity and lower oil absorption capacity. The mechanical properties of the extruded feeds were significantly different from each other, most likely due to the complex nature of texture formation with respect to process parameters and properties of ingredients.     

以大口黑鲈和大黄鱼配合饲料应用为例谈 改变鱼类营养和饲料研究范式

鱼类营养和饲料研究始于70年前并借鉴陆生动物营养研究经验形成了研究范式。在过去70年中,鱼类营养和饲料研究取得了大量的成果,这些研究成果推动了水产配合饲料技术的进步,为水产饲料产业从无到有、从小到大做出了贡献。然而,随着全球水产养殖规模的不断扩大,水产养殖发展面临的资源和环境压力日益增加,对水产饲料也提出了更高的要求。事实表明,根据一些鱼类营养和饲料研究成果所配方的饲料在养殖生产实践中往往不能取得预期的应用效果,这意味着在已有范式下取得的研究成果有时难以很好地满足现代鱼类养殖产业的需要。本文叙述了具有重要经济价值的两种肉食性鱼类大口黑鲈和大黄鱼配合饲料研发与应用的历程,指出对饲料蛋白需求的低估是限制配合饲料长期未能在大口黑鲈和大黄鱼养殖生产中应用的主要原因。早期研究报道大口黑鲈的饲料蛋白需求为400-440 g/kg,大黄鱼的饲料蛋白需求为450-470 g/kg。经过重新评估后将大口黑鲈和大黄鱼的最适饲料蛋白水平分别提高到480-510 g/kg和490-520 g/kg。在适宜的饲料蛋白水平下,投喂配合饲料的大口黑鲈和大黄鱼生长与投喂冰鲜鱼时相当。作者认为对饲料蛋白需求的低估与已有鱼类营养和饲料研究范式存在的不足有关,其表现为：（1）强调食物对鱼类生长的作用,但忽视了实验鱼遗传背景和食物以外的环境条件对生长和摄食的影响;（2）强调鱼类个体生长对评价营养需求和饲料质量的重要性,但忽视了鱼类个体生长差异并不能完全反映养殖产量和效益的事实;（3）强调生长和饲料利用效率作为鱼类营养和饲料研究评价指标的重要性,但忽视了养殖对环境和自然资源的负面影响是限制水产养殖产业可持续发展的瓶颈;（4）没有足够重视基础饲料配方在评价营养需求或饲料质量方面的影响,一些研究因基础饲料组成不当而产生没有实际意义的评价结果。针对上述问题,作者建议从概念、理论和研究方法方面对已有的范式做如下修改：（1）重视鱼类遗传背景和食物以外的环境条件对鱼类生长的影响,明确鱼类营养需求取决于其生长需求;（2）重视食物中各种营养素之间的相互作用,明确不同饲料原料在实现配方的营养平衡方面发挥着不同的作用;（3）重视对实验鱼种质和种群结构的选择,重视对照组和处理组个体生长差异的幅度对判断饲料处理效应的指示作用,重视饲料配方对渔业资源和环境等水产养殖可持续发展相关的内容的影响。经过修改后的研究范式更符合养殖生产实际,在此基础上开展研究所获得的成果也能够更好地指导配合饲料生产,为鱼类养殖产业的可持续发展提供更好的科技支撑。     

Evaluation of alternative pond production systems for raising largemouth bass,Micropterus salmoides

This study evaluated three different pond‐based production systems for raising largemouth bass, Micropterus salmoides, for the food fish market, using nine 0.04‐ha ponds. Treatments included traditional ponds (TP), intensively aerated ponds (IAP), and split‐pond systems (SPS). TP and SPS ponds were aerated at 9.3 kW/ha, while IAP was aerated at 18.6 kW/ha. TP was stocked at 7,500 fish per ha (three replicates per treatment), and the other two production systems (SPS, IAP) were stocked with 12,500 fish per ha. Feed‐habituated advanced fingerlings (128 ± 47.6 g mean individual weight) were cultured for 157 days. Fish were fed a formulated diet (42% protein, 16% lipid) four times a day, feeding with a maximum allowance of 3% of total body weight and readjusted to the initial body weight biweekly. Fish raised in the SPS displayed a significantly lower specific growth rate, lower individual final weight, and lower weight gain, but the biomass gained was significantly higher than TP but not IAP. Final biomass gained was 50% higher in the SPS and IAP than in the TP. Survival rate and feed conversion ratio were not significantly different among treatments and ranged from 71 to 79% and 1.64 to 2.14, respectively.     

Diet of introduced largemouth bass in Korean rivers and potential interactions with native fishes

Abstract –  A dietary analysis of largemouth bass ( Micropterus salmoides ), an exotic, piscivorous species, was conducted in large South Korean river systems (>third order streams, 31 sites). Micropterus salmoides larger than 100 mm exhibited intense piscivory on native Korean juvenile fishes, with levels of piscivory amongst the highest recorded globally, for native and introduced populations. Largemouth bass exhibited an ontogenetic shift in diet, showing a progressive increase in piscivory with size, typical of this species within its native range but unlike several studies on introduced largemouth bass in Europe and Africa. Sampling of fish communities at the same sites used for diet studies showed that native piscivores and the main food fish species of largemouth bass were significantly less abundant ( P  = 0.049 and 0.045, respectively) at sites where bass were present than at sites where no bass were recorded. Largemouth bass may pose a threat to the structure of fish assemblages in Korean river systems and further study of their population interactions and how to minimise their spread is needed.     

Digestibility of plant protein-based diets by largemouth bass Micropterus salmoides

Commercial farming of carnivorous fish demands the reduction of environmental impact of feeds; that requires minimal use of dietary animal protein. This study investigated the digestibility of diets formulated exclusively out of plant protein, added feed attractants, by the carnivore largemouth bass, Micropterus salmoides . Juvenile largemouth bass (14.0 ± 1.0 cm) conditioned to accept artificial, dry feed were confined in polypropylene cages and fed ad libitum in three daily meals, seven experimental diets containing varying levels of vegetable and animal protein sources, added of different feed stimulants. After last daily meal, cages were transferred to cylindrical–conical-bottomed, 200-L aquaria, where faeces were collected by sedimentation into refrigerated containers, preserved and later analysed for chemical composition. Soybean meal can be used as partial substitute of animal protein in diets for largemouth bass; the poultry by-product meal shows as a good option as animal protein source in these rations. Control treatment – 50PP : 50AP – yielded best performances; the need for the use of fish meal in the formulation for carnivorous diets is, at least, questionable. Results of the digestibility trials demonstrated the importance of determining the diet digestibility, if precision in the formulation of least-cost feeds for carnivorous fish is the ultimate goal.     

Effect of fishing effort on catch rate and catchability of largemouth bass in small impoundments

Largemouth bass Micropterus salmoides (Lacepède) catch rates decline with sustained fishing effort, even without harvest. It is unclear why declines in catch rate occur, and little research has been directed at how to improve catch rate. Learning has been proposed as a reason for declining catch rate, but has never been tested on largemouth bass. If catch rate declines because fish learn to avoid lures, periods of no fishing could be a management tool for increasing catch rate. In this study, six small impoundments with established fish populations were fished for two May to October fishing seasons to evaluate the effect of fishing effort on catch rate. Closed seasons were implemented to test whether a 2‐month period of no fishing improved catch rates and to determine whether conditioning from factors other than being captured reduced catch rate. Mixed‐model analysis indicated catch rate and catchability declined throughout the fishing season. Catch rate and catchability increased after a 2‐month closure but soon declined to the lowest levels of the fishing season. These changes in catch rate and catchability support the conclusion of learned angler avoidance, but sustained catchability of fish not previously caught does not support that associative or social learning affected catchability.     

Effect of extrusion cooking temperature on the microstructure of extruded pellets

ABSTRACT:   The microstructure of extruded pellets (EP) for fish under various extrusion cooking temperatures was studied by using a twin-shaft extruder. As the extrusion cooking temperature increased, the expansion rate increased and the bulk density of EP decreased. The liquefaction of the material started because of the increase in inner material temperature, the decrease in inner material pressure, and the decrease in main motor amperage. Thus, the microstructure of EP changed depending on the extrusion cooking conditions, that is, the extrusion cooking temperature effected greatly the liquefaction of the material. Generally, when the extrusion cooking temperature increased, the expansion rate increased, but a suitable temperature was found for a maximum expansion rate. The microstructure of the EP was caused by the liquefaction of the material and the microstructure effects on the function of EP. For example, the water holding capacity was affected by the inner bubble structure of an EP. These functions affect the character of the feed. EP produced under suitable conditions can have additional functions for feed.     

Production performance of largemouth bass Micropterus salmoides and water quality variation in monoculture,polyculture and integrated culture

A 74‐day experiment was conducted to evaluate the production performance and water quality variation in three types of farming system for largemouth bass Micropterus salmoides. The tested aquaculture models included monoculture of largemouth bass (MC), polyculture of largemouth bass, gibel carp Carassius auratus gibelio and silver carp Hypophthalmichthys molitrix (PC), and integrated culture of largemouth bass, gibel carp, silver carp and freshwater pearl mussel Hyriopsis cumingii (IC). The ratio of largemouth bass, gibel carp and silver carp was 30:2:1 in the PC model, and the ratio of largemouth bass, gibel carp, silver carp and mussel was 30:2:1:5 in the IC model. The largemouth bass were fed with formulated feed twice daily. No significant differences were found in weight gain and yield of largemouth bass, total fish yield, nitrogen (N) and phosphorus (P) utilization efficiencies, N and P wastes, pH, nitrite, nitrate, reactive phosphate, total nitrogen, total phosphorus, total organic carbon, chemical oxygen demand, 5‐day biochemical oxygen demand, chlorophyll a, primary productivity among the MC, PC and IC models. The ammonia was lower, while the dissolved oxygen was higher in the PC tanks than in the MC tanks. These results suggest that the environment situation was better in the PC tanks relative to that in the MC tanks. The present study reveals that the PC model should be a way to optimize the aquaculture model for commercial largemouth bass farming.     

Potential of indigenous Bacillus spp. as probiotic feed supplements in an extruded low‐fish‐meal diet for juvenile olive flounder,Paralichthys olivaceus

A 12‐week feeding trial was designed to assess the probiotic potential of indigenous Bacillus amyloliquefaciens and/or Bacillus subtilis singly or in combination with Bacillus licheniformis in an extruded feed for olive flounder (Paralichthys olivaceus) juveniles. A high fish meal (FM) diet (control) and a low‐FM diet containing an alternative protein blend (30% FM replacement, FM30) were formulated. Three other experimental diets were prepared by inclusion of B. amyloliquefaciens (BA), B. subtilis (BS), or a mixture of B. amyloliquefaciens, B. subtilis, and B. licheniformis (BASL) into FM30 diet, with a final concentration of 10⁶ CFU/g diet. Results indicated that the FM30 diet was well tolerated by flounder, and the overall performance was not affected by dietary treatments. Lysozyme activity and total immunoglobulin level were significantly reduced in flounders when fed with the FM30 diet compared with the BASL and BA diets, respectively. The Bacillus additives neither enriched the relative abundance of the corresponding Bacillus spp. in the relevant gut microbiota of olive flounder nor modulated the presumptive gene functions of the gut microbiome. Despite the absence of growth‐promoting effect, the tested probiotics could still be economically viable for use as immunostimulants in commercial flounder diets with partial FM replacement.     

Effect of catch-and-release angling on growth of largemouth bass, Micropterus salmoides

Catch‐and‐release angling is popular in many parts of the world and plays an increasingly important role in management of recreational fisheries. Although the magnitude of catch‐and‐release mortality is well documented for many species, potential sublethal effects have been little studied. An experiment was conducted to assess directly the effects of catch‐and‐release angling on growth of largemouth bass, Micropterus salmoides Lacépède. Angling mortality was 0.00 ± 0.092% for largemouth bass caught on plastic grubs. There was no difference (P = 0.57) in weight gain between caught and uncaught fish over a 40‐day angling and recovery period. Although catch‐and‐release angling appears to have no effect on largemouth bass growth, previous studies documented sublethal effects on growth and reproduction in other species, suggesting that the occurrence and magnitude of sublethal effects vary among species.