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1.
采用4种饵料投喂中国对虾(Fenneropenaeus chinensis)幼虾,用投喂感染的方法人工感染WSSV。测定体长、体重以及各组的攻毒存活率,实验周期15d。ANOVA分析结果表明,投喂鲜活卤虫组体长、体重的增长明显优于其他各组,差异达极显著水平(P〈0.01);投喂人工配合饵料实验组的体长、体重增长量最小;投喂鱼肉组体长增长慢于投喂蛤蜊肉组,而体重的增长快于投喂蛤蜊肉组,差异均不显著(P〉0.05)。投喂卤虫成体和投喂鱼肉两组的攻毒存活率最高,明显高于投喂配合饵料和蛤蜊肉两实验组,差异达极显著水平(P〈0.01);投喂卤虫组和投喂鱼肉组之间存活率无显著差异(P〉0.05),投喂人工配合饵料组和蛤蜊肉组差异不显著(P〉0.05)。巢式PCR检测表明,人工感染前的中国对虾幼虾少数携带WSSV,人工感染后全部个体检测到病毒特征片段。  相似文献   

2.
卤虫在不同饵料培养介质中的生长规律   总被引:6,自引:0,他引:6  
以啤酒酵母和单胞藻为投喂饵料,新疆艾比湖卤虫(Artemia parthenogenetica)为投喂对象,建立三个实验组分别进行研究,观察在不同饵料条件下艾比湖卤虫的生长,探讨不同饵料对卤虫的生长、成活的影响。通过对卤虫体长和存活率的测量,建立了卤虫在不同饵料情况下的生长方程、生长曲线和存活率曲线,并通过对方程和曲线的分析获得以下结论:投喂单胞藻组卤虫的生长最慢,存活率最低25表面以后全部死亡;投喂酵母组卤虫生长最快,在0≤t≤42.6时体长值最高,存活率较低,投喂单胞藻和酵母的混合饲料组卤虫的前期生长次于酵母组,后期生长超过之,存活率较高且成熟个体产虫量和产卵量也多于酵母组。  相似文献   

3.
卤虫(Artemia)是对虾苗种培育重要的生物饵料.本研究将产自美国大盐湖,以及中国新疆艾比湖、西藏双湖和渤海湾盐田卤虫卵孵化的幼体投喂凡纳滨对虾(Litopenaeus vannamei)仔虾,研究不同产地卤虫幼体对凡纳滨对虾仔虾生长、存活、肌肉组分、抗氨氮能力和盐度耐受力的影响.凡纳滨对虾仔虾随机分为4组,每组3个...  相似文献   

4.
不同饵料对日本囊对虾的生长与存活的影响   总被引:1,自引:0,他引:1  
研究不同饵料对日本囊对虾生长、存活与饵料系数的影响,实验设置5个饵料种类,人工合成饲料、新鲜蛤仔肉、冰冻丰年虫成虫、人工合成饲料+新鲜蛤肉、人工合成饲料+冰冻丰年虫成虫,每个组合设置3个重复实验。结果表明,饵料对日本囊对虾生长性状、存活率与饵料系数均有显著影响(P0.05)。投喂人工合成饲料+冰冻丰年虫成虫组合的效果显著大于投喂人工合成饲料组合(P0.05),投喂新鲜蛤仔肉组合与投喂人工合成饲料组无统计学意义差异(P0.05);存活率的变化范围为(71.86±9.05)%~(86.89±3.11)%,投喂丰年虫组与投喂人工合成饲料+新鲜蛤肉组的存活率分别为最高和最低;饵料系数的变化范围为(2.00±0.06)~(2.87±0.12),投喂饲料+丰年虫组合与投喂人工合成饲料组的饵料系数分别为最低和最高。综合分析表明:投喂人工合成饲料+冰冻丰年虫成虫组合为最优组合,其次是人工合成饲料+新鲜蛤肉组合,在该条件下对虾生长速率较快、饵料系数低。  相似文献   

5.
以中国对虾(Fenneropenaeus chinensis)为实验材料,分别投喂配合饲料、蚯蚓、蛤蜊、蝇蛆等四种饵料,利用生长和抗病性指标综合评价蚯蚓和蝇蛆作为中国对虾饵料的可行性。生长实验前测定每个实验组的初始体长和体重,养殖40d后再次测定生长指标,之后,分别投喂不同毒饵量进行人工感染实验。方差分析表明:投喂四种饵料后,蛤蜊组生长最快,其次是蚯蚓,再次是蝇蛆,最后是配合饲料,各组之间对虾体长增长差异显著(P<0.05),体重增长差异极显著(P<0.01) 。利用线性固定模型分析不同饵料及不同病毒量感染下对中国对虾存活率的影响,其中蚯蚓组存活率最高,配合饲料组存活率最低,并且蚯蚓组存活率显著高于蛤蜊组和配合饲料组(P<0.05),蝇蛆组显著高于配合饲料组(P<0.05)。研究结果表明:蚯蚓和蝇蛆可显著提高中国对虾的生长速度,明显提高中国对虾的抗病性,是很好的对虾饵料。  相似文献   

6.
卤虫在WSSV病毒病传播中的媒介作用   总被引:3,自引:0,他引:3  
2003年8月对卤虫进行投喂(浸泡)感染,并进行中国明对虾投喂实验。各组对虾阳性感染率的单因素方差分析比较结果表明,卤虫可以携带有活性的WSSV病毒粒子,并可通过摄食导致对虾间接地携带病毒,但病毒感染能力有限。卤虫病理切片观察结果显示,攻毒后卤虫细胞核没有显著深染及核肿大现象,但无论是横切还是纵切均显示有上皮脱落、部分组织结构松散、细胞结构不完整现象。本试验确定卤虫成体可以携带WSSV并通过投喂感染对虾,使其潜在携带病毒,仔虾阶段投喂成体卤虫应经过严格检疫,制作含有经过检疫卤虫的微囊饵料作为卤虫及其他鲜活饵料的替代品或许是有效的防病措施。  相似文献   

7.
用两只容积为8吨的实验水槽,分别培养400万尾中国对虾无节幼体,其中1号水槽投喂豆浆、蛋黄代用饵料,2号水槽投喂三角褐指藻、褶皱臂尾轮虫和卤虫,至仔虾幼体X期(P_(10))进行计数。前者变态成活率为23.4%,后者变态成活率为65.7%;且个体体长亦为后者大于前者,表明用生物饵料优于代用饵料。  相似文献   

8.
用高纯度单一ω-3和ω-6系列脂肪酸、亚油酸、亚麻酸、花生四烯酸以及二十二碳六烯酸,分别以饵料1%的含量添加到含脂类4%棕榈酸和油酸的基础饵料中,组成四种试验饵料。对照饵料的脂类组成为5%的棕榈酸和油酸。对中国对虾幼虾进行32天的投喂试验,测定ω-3和ω-6系列不饱和脂肪酸对幼虾存活、蜕皮和生长的影响。结果表明,投喂不含ω-3和ω-6系列脂肪酸的对照饵料,幼虾生长几乎停止,存活率极低。添加1%的亚油酸或亚麻酸或花生四烯酸,效果较好;添加1%的二十二碳六烯酸,效果最佳。说明ω-3和ω-6系列不饱和脂肪酸对中国对虾幼虾的存活和正常生长是必需的。  相似文献   

9.
在水温(22±1)℃、盐度(32±1)和90 W太空灯每日光照12 h、昏暗12 h下,将形态完整、活力强的伞径(3.5±0.5)cm的大西洋金黄水母(Chrysaora quinquecirrha)幼水母体放入200 L亚克力环形实验缸中,投喂海月水母(Aurelia aurita)、卤虫(Artemia)无节幼体、大黄鱼(Larimichthys crocea)鱼卵、大银鱼(Protosalanx hyalocranius)肉、糠虾、桡足类和卤虫成虫,研究这7种天然饵料对大西洋金黄水母幼水母体存活和生长的影响。结果表明,(1)不同饵料显著影响幼水母体的存活率(P<0.05),各处理组存活率由高到低依次为:海月组、卤虫无节幼体组、卤虫成虫组、鱼卵组、鱼肉组、糠虾组和桡足类组,其中海月组的存活率显著高于其他组(P<0.05);(2)不同饵料显著影响幼水母体的生长(P<0.05),各处理组生长速度由快到慢依次为:卤虫无节幼体组、卤虫成虫组、海月组、鱼肉组、糠虾组、鱼卵组、桡足类组,其中卤虫无节幼体组生长速度显著快于其他组(P<0.05)。卤虫无节幼体、卤虫成虫和海...  相似文献   

10.
在水温(30±1)℃条件下对人工孵化的云斑尖塘鳢(Oxyeleotris marmorata)仔鱼进行转饵期不同投喂策略实验,对仔鱼生长和成活情况进行了研究,设计5个投喂组:轮虫投喂组(A组);70%轮虫+30%卤虫投喂组(B组);50%轮虫+50%卤虫投喂组(C组);30%轮虫+70%卤虫投喂组(D组);卤虫(幼虫)投喂组(E组)。结果显示:云斑尖塘鳢仔鱼对卤虫的摄食强度随卤虫在饵料中比例的升高而增大,其对混合饵料中轮虫和卤虫的摄食强度的比值(Ir/Ia)随食物组成的变化发生相应的变化。以轮虫-卤虫不同比例的混合饵料投喂时,D组仔鱼的增长率、增重率最高,可存活率不足50%,高于E组,显著低于其它各组;C组仔鱼生长指标略低于D组,但存活率为(74.00±2.29)%,综合指标显著好于其它各组。当混合饵料中轮虫和卤虫各占50%时,10日龄开始投喂组仔鱼的全长(13.07±0.13)mm,特定生长率(10.25±0.37)%/d,存活率(82.14±0.72)%,综合生长指标最好。结果表明,云斑尖塘鳢仔鱼转饵期进行联合投喂的最佳饵料比例为50%轮虫+50%卤虫,最佳转饵时间为10日龄。  相似文献   

11.
The survivorship and growth rates of juvenile, hatchery rearedPsammechinus miliaris (Gmelin) were observed for seaurchins fed different diets, and maintained at varying stocking densities andlocations (tank or sea-based). In addition survivorship and growth of secondgeneration hatchery stock was also recorded. Somatic growth rates of juvenileurchins (initial test diameter 6.5 mm SD 1.26) were measured over9months. A high lipid, high protein diet supported higher somatic growth ofurchins in this size range. Higher stocking densities (4 individualsl–1 as opposed to 2 individuals l–1)adversely affected growth as did location (sea-based urchins being smaller thantank based) although survivorship in all treatments and in both first andsecondgenerations was exceptionally high. Further research is required to designdietspromoting somatic rather than gonadal growth in urchins below market size.  相似文献   

12.
Mithraculus forceps (A. Milne Edwards) has demonstrated a great potential for ornamental aquaculture and the present study tests the effects of temperature, stocking density and diet on the survival and growth of M. forceps juveniles. For 28 days post metamorphosis (DPM), the newly metamorphosed juveniles were reared at two temperatures (25±0.5 or 28±0.5°C), stocked at five densities (1, 5, 15, 30 or 60 crabs ring−1; approximately 226, 1132, 3395, 6791 or 13 581 crabs m2 respectively) and fed with commercial pellets (CP), microalgae (Amphora spp.), live newly hatched Artemia nauplii (NHA), frozen Artemia nauplii (FNHA), or combinations of each of these diets with NHA. At the end of the temperature experiment, carapace width of the crabs cultured at 28°C was significantly larger than the crabs reared at 25°C and average intermolt period was significantly shorter. Increased stocking density had a negative effect on survivorship and growth. Survivorship at the end of the diet experiment was significantly different between the crabs not fed, fed with CP and Amphora and the crabs fed with the other diets. Between the diet treatments, the crabs fed with NHA+Amphora were significantly larger than the ones fed with NHA+FNHA, NHA, FNHA and NHA+CP, and these in turn larger than ones fed with Amphora.  相似文献   

13.
本实验以平均初始体重为15.60 g的红鳍东方鲀(Takifugu rubripes)幼鱼为研究对象,研究饲料中蛋白含量及养殖密度对红鳍东方鲀幼鱼生长性能、氮排泄及相关生理生化指标的影响。设计两因素三水平(2×3)实验,配制3种不同蛋白梯度(38.87%、45.55%和51.00%,干重)的等脂实验饲料,设置3个密度梯度为1.53 kg/m^3(0.196 m3体积的实验桶,每桶20尾鱼)、2.30 kg/m^3(每桶30尾鱼)和3.06 kg/m^3(每桶40尾鱼)。每组饲料设3个重复,养殖实验为期56 d,在室内流水系统内进行。结果显示,增重率在高、中蛋白组显著高于低蛋白组(P<0.05),但当饲料蛋白含量一定时,养殖密度对增重率没有显著性影响。饲料蛋白含量和养殖密度对鱼体常规成分没有显著性影响。当饲料蛋白一定时,高密度组的血清总蛋白和胆固醇含量显著高于中密度组(P<0.05)。血清总蛋白含量在低蛋白组显著高于中蛋白组(P<0.05)。血清碱性磷酸酶含量在低蛋白组显著高于高蛋白组(P<0.05)。饲料蛋白含量和养殖密度对红鳍东方鲀幼鱼的生长、氨氮排泄没有显著性交互作用。静水投喂3 h后,氨氮排泄率在高密度组显著高于低密度组(P<0.05)。研究表明,45.55%饲料蛋白质含量已经能够满足红鳍东方鲀幼鱼正常生长的需求。饲料蛋白含量和养殖密度对红鳍东方鲀幼鱼的生长性能和氨氮排泄没有显著性交互作用。  相似文献   

14.
Juvenile red king crabs (RKCs) Paralithodes camtschaticus have a strong tendency for cannibalism, which is an obstacle for seedling production. We investigated the effects of density-dependent cannibalism on the survival rate and on growth, and estimated the optimal stocking density. Four different stocking densities of juvenile first instar crabs were maintained in tanks (50, 100, 200 and 400 individuals per 100-l tank: bottom area was 0.25 m2) during the 209 or 216 days of rearing. The survival rate was affected by stocking density, elapsed days, and the interaction between these variables. Although carapace length, an index of body size, was also affected by density, elapsed days, and the interaction between these variables, the effect associated with density was quite small, suggesting that cannibalism did not intensely affect growth of juvenile crabs. We then estimated the initial stocking density that maximizes the number of survivors using parameters of analyses. Optimal initial stocking density was predicted as 416, 197 and 149 individuals per tank when the target size was assumed as 5.0, 10.0 and 15.0 mm, respectively. This estimation provides a baseline for seedling production in RKCs and could be further improved by considering other factors that affect survival and growth of RKCs.  相似文献   

15.
The objective of this study was to evaluate the production response of Litopenaeus vannamei fed with production diets containing increasing percentages (0, 4, 8, and 12%) of soy protein concentrate (SPC). The diets were commercially produced and evaluated in outdoor tanks and 0.1-ha production ponds. In the outdoor green water tank system, the four test diets and a commercial reference diets were offered to juvenile shrimp (1.0 g initial weight) reared over a 10-week period at a stocking density of 30 shrimp per tank. At the conclusion of the tank trial, there were differences in final weight (13.5–15.0) biomass (399 g–432 g), and FCR (1.17–1.28) with the reference diet generally producing significantly better results than the test diets albeit there were no significant differences among the SPC test diets. In addition, the test diets were evaluated in 0.1-ha ponds using four replicates per diet. Nursed juvenile shrimps (0.013 g initial weight) were stocked at 35 shrimp m−2 and were cultured under standardized pond production conditions for 18 weeks. At the conclusions, net yield (4,190–5,051 kg/ha), final mean weight (13.5–15.7 g), survival (86.7–93.3%), and FCR (1.3–1.59) were evaluated with no significant differences between dietary treatments. The results from this study demonstrated that SPC inclusion up to 12% SPC in soybean-based diet can be used in commercial feed formulations for L. vannamei without causing negative effect on growth, feed conversion, survival and net yield.  相似文献   

16.
The impact of stocking density on growth performance, physiological indicators, and body composition of juvenile blunt snout bream in recirculating aquaculture system was investigated in this study. Juvenile blunt snout bream were raised at stocking densities of 75, 150, 225, 300, and 450 fish/m3 for 12 wk with three replicate tanks at each density. All treatment tanks were supplied with water from the same recirculating system to ensure uniformity of water quality across groups. This study has shown that higher stocking densities had a negative effect on individual growth performance. Final body mass, specific growth rate (SGR), and weight gain decreased significantly as stocking density increased. Individual body mass as well as body length were more uniform in fish stocked at densities of 75 and 150 fish/m3 than in other groups. Stocking densities of 225 and 300 fish/m3 resulted in significant increases in serum total protein, triglyceride, lactate, and cholesterol levels, whereas blood glucose concentrations decreased significantly. In addition, decreased body lipid content and increased body moisture content were observed at stocking densities of 300 and 450 fish/m3. Overall, a density of 150 fish/m3 resulted in higher SGR and more uniform size among juvenile blunt snout bream.  相似文献   

17.
A 30-day feeding experiment was conducted in 160-L plastic tanks to evaluate the potential use of Artemia biomass as a protein source in practical diets for postlarval Macrobrachium rosenbergii (initial mean weight of 12.12–12.29 mg). Nine isoenergetic and isonitrogenous experimental diets (approximately 40% crude protein) were formulated by replacing levels of the fishmeal (FM) protein difference either with dried or frozen Artemia (0, 25, 50, 75 and 100%). The 0% Artemia treatment, in which Peruvian FM was the only main protein source, was considered to be the control diet. The results showed that prawn postlarvae (PLs) fed the FM control diet had a lower survival (46%) compared with all Artemia diets. Significant differences ( P <0.05) were, however, only found at 75% and 100% Artemia protein inclusion levels (survival of 68–77%). A gradual increase in growth performance (live weight gain, specific growth rate and total length) of the prawns was achieved on increasing dietary inclusion of Artemia protein. Additionally, the size distribution exhibited the same response as growth performance. However, prawns fed the frozen Artemia diets showed a better performance than the ones fed the dried Artemia diets. It can be suggested that Artemia biomass may totally replace FM in practical diets for PLs of the freshwater prawn M. rosenbergii .  相似文献   

18.
ABSTRACT

In temperate regions, post-larvae freshwater prawn, Macrobrachium rosenbergii, are grown to more advanced sizes in tanks prior to pond stocking. This intermediate stage of culture is referred to as the nursery period. Little research has been conducted on different management practices on juvenile prawn growth and survival during this 30-60 day period. Survival during the nursery stage has been highly variable and may be related to the cannibalistic behavior of juvenile freshwater prawn when cultured at high densities in the nursery. The objective of this study was to evaluate the effect of stocking density, relative to the provision of artificial substrate (number of prawns/m2 of substrate), on growth, survival, and economic variables for freshwater prawn juveniles during nursery production. Post-larvae (0.01%0.00 g, n = 300) were stocked into nine 1900 L tanks, each provided with 20.5 m2 of artificial substrate in the form of horizontal layers of black plastic mesh (10 mm) spaced 5 cm apart. Tanks were randomly assigned one of three prawn densities (215, 430, or 860 post-larvae/m2 of substrate), which equated to 2.3,4.6 and 9.2 prawn/L, respectively. Juvenile prawn were fed a commercial trout diet (42% protein) at a percentage of body weight according to a feed rate table. Water quality was maintained using a flow rate of 8 L/min in each tank from a reservoir pond. Temperature was maintained at approximately 28°C using heat pumps. After 56 days there was no significant difference (P >0.05) in average weight of juvenile prawn stocked at the three densities (0 = 0.58%0.12 g, n = 9). Survival was significantly lower (P <0.05) for prawn stocked at 860 m2 (62%) than in those stocked at 430/m2 (78%) and 215/m2 (94%), which were not statistically different (P >0.05). Even with reduced survival, the highest stocking density produced the greatest number of nursed juveniles based on both tank volume (5.5/l) and surface area (530/m2), at the lowest average cost.  相似文献   

19.
将体长为(3.59±0.26)cm的凡纳滨对虾(Litopenaeus vannamei)按1 800尾.m-3、1 500尾.m-3和1 200尾.m-3的密度分别饲养在注水0.3 m3的圆形玻璃纤维桶(容量为0.5 m3)中30 d,检测了基本水质因子、对虾肝胰腺和肌肉组织中的酚氧化酶(PO)活力、超氧化物歧化酶(SOD)活力、抗菌活力(Ua)、碱性磷酸酶(AKP)活力、体质量增长和成活率,研究了不同放养密度对凡纳滨对虾稚虾免疫指标及生长的影响。统计分析发现,试验过程中水体理化因子均在适宜范围,各处理间水质因子的差异不显著;对虾的PO活力、Ua和AKP活力均随着密度的增加而降低,SOD活力则反之;对虾的体质量增长、体质量特定增长率和成活率随着密度的增加而降低,成活率差异显著(P〈0.05)。结果表明,凡纳滨对虾(体长〈4.8 cm或体质量〈1.2 g)在密度为1 200~1 800尾.m-3时,密度胁迫可明显影响其免疫指标和生长。  相似文献   

20.
The present work evaluated the effect of three inexpensive diets (frozen minced mussel and edible cockle (MMC), frozen minced squid (MS) and gilthead seabream feed (GSF)) on growth, survival, sex reversal, lipid classes and fatty acid (FA) profile of juvenile ornamental shrimp Lysmata seticaudata. Shrimp fed GSF displayed the highest survival rate (±SD) (85.2±1.8%) and the highest percentage (±SD) of shrimp changing from male to simultaneous hermaphrodite (SH) phase (25.2±2.2%). All diets promoted growth rates superior to those reported in the wild, with SH shrimp displaying higher total lengths (TL). Shrimp in SH phase fed GSF displayed the highest TL (±SD) (40.6±1.2 mm). Cultured shrimp reflected the lipid content of experimental diets, with shrimp fed GSF displaying the highest triacylglycerols and sterols (ST) contents. The higher rearing density induced by lower mortality rates of shrimp fed GSF, and the high ST levels present in the diet, may explain the higher proportion of shrimp in SH phase. The higher levels of highly unsaturated fatty acids (HUFA) displayed by MS did not promote higher survival or growth rates. The low polyunsaturated fatty acids and HUFA content of MMC was not reflected in cultured shrimp, probably because of a selective retention of these FA.  相似文献   

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