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31.
日本囊对虾亲虾人工繁育技术初步研究   总被引:2,自引:0,他引:2  
2003年11月18日~2004年6月18日期间,采用人工养殖的日本囊对虾,经过越冬培养和室外培育(性腺促熟、交尾),人工控制光线、饵料、温度和培育密度等手段,亲虾性腺均可发育成熟。在越冬培养中光线为500~800lx之间、温度为9~10℃、饵料为沙蚕及杂色蛤,亲虾培育密度为12~30尾/m^2,越冬实验结果,亲虾体重增长率为10.9%,存活率为93.2%。在室外培育中温度为13.6℃、养殖密度为1.3尾/m^2,饵料以蜾赢蜚、藻钩虾和低值贝类为主。实验结果,亲虾体重增长率为5.1%、存活率为90.5%、交尾率为100%。2004年6月24日~7月10日利用人工繁育的日本囊对虾亲虾进行苗种生产实验。实验结果,每尾亲虾产卵量为20~25万粒/尾、孵化率为82.96%、出苗率为62.8%。实验表明,人工繁育的日本囊对虾亲虾可用于正常的苗种生产。  相似文献   
32.
为评估增殖放流对日本囊对虾(Marsupenaeus japonicus)群体遗传多样性的影响,本研究分析了放流前捕捞渔获群体(FLQ)、放流后捕捞渔获群体(FLH)以及放流虾苗群体(FLXX)的遗传多样性水平。3个群体共测定了135尾日本囊对虾的线粒体D-loop序列,经比对分析确定测得的序列长度为938 bp,检测到237个变异位点,177个简约信息位点,定义了100种单倍型。经分析,核苷酸多样性指数由大到小依次为FLQ、FLH、FLXX,单倍型多样性指数大小为FLQ=FLHFLXX。AMOVA分析表明FLQ和FLH群体的遗传分化系数(F_(st))值为0.00629,其小于0.05,表明变异主要来自于群体内,且群体间无分化。FLH与FLXX的F_(st)值为0.08151(P0.01),其大于0.05,表明遗传变异大多发生在群体内,但群体间呈低度分化。Tajima’s D和Fu’s Fs中性检验结果均为负值,表明这3个群体偏离了中性模式,可能受到群体扩张和自然选择的作用。综上所述,增殖放流前后日本囊对虾群体均保持较高的遗传多样性水平,变异不存在显著性差异,且群体间无分化,说明增殖放流是目前维持日本囊对虾种质资源量较为有效的措施之一。  相似文献   
33.
Water temperature is an essential environmental factor in aquaculture that affects many aspects of organism, and a rise in water temperature stresses aquatic animals. HSP60 is a major component of the chaperone system and plays an important role in stress response. In this study, the full‐length cDNA sequence of HSP60 from Marsupenaeus japonicus was cloned for the first time, and the tissue distributions and expression profiles of MjHSP60 at the early developmental stages of Mjaponicus and under heat stress were verified by qRT‐PCR. The full‐length cDNA sequence of MjHSP60 was 2,303 bp with the deduced amino acid (AA) sequence of 579 AA. MjHSP60 was expressed in all eight tested tissues of Mjaponicus and was mainly expressed in the hepatopancreas under normal condition. MjHSP60 was expressed in all of the early developmental stages examined from the fertilized egg to the post‐larval stage, and the expression level of MjHSP60 peaked at zoea II and reached a trough at the transition periods between each two stages (N and M1) and showed a relatively stable expression level at the post‐larval stage. The expression level of MjHSP60 was significantly up‐regulated in the gills, muscle, heart, hepatopancreas and stomach at 3 hr post‐heat‐stress and showed varied sensitivity to heat stress. The expression profile of MjHSP60 in the hepatopancreas and gill showed a time‐dependent manner post‐heat‐stress and peaked at 3 hr post‐heat‐stress. The present study provided a basis for further studies for elucidating the function of MjHSP60 in the heat stress response and the early developmental stages of Mjaponicus.  相似文献   
34.
[目的]为探究不同包装对丁香鱼干常温贮藏期间的品质特性影响,[方法] 以空气包装为对照,与真空包装、气调包装和CO2包装做比较,测定贮藏过程中菌落总数、TVB-N、POV、TBA、色差、挥发性风味成分及感官评分的变化。[结果]结果显示,真空、气调、CO2三种包装均能有效抑制丁香鱼干微生物生长,常温25 ℃贮藏8 d后,真空包装组样品TVB-N、POV和TBA值分别较空气包装组降低47.08%、4.13%和25.49%,并且真空包装组样品在减缓样品色泽变化、保护肌纤维结构完整性、保留挥发性风味成分和保持感官特性方面均具有较佳效果,确定了真空包装为丁香鱼干的最佳包装方式。基于Arhenius方程建立了丁香鱼干货架期预测模型,25 ℃和35 ℃下真空包装丁香鱼干的货架期分别为6.07和3.23 d。[意义]本研究成果可为丁香鱼干常温物流过程中的品质控制提供理论依据。  相似文献   
35.
银杏大蚕蛾生物学及无公害防治   总被引:3,自引:0,他引:3  
银杏大蚕蛾在江西1年发生1代,以卵越冬,对其形态、生物学进行报道,提出无公害防治措施系统。  相似文献   
36.
JUN  OHTOMI  TAKUYA  TASHIRO  SHIN  ATSUCHI  NATSUKI  KOHNO 《Fisheries Science》2003,69(3):505-519
ABSTRACT:   The Yatsushiro Sea and Shibushi Bay are, respectively, located on the western and south-eastern coast of Kyushu, southern Japan. The Yatsushiro Sea is a shallow semi-enclosed inland sea, whereas Shibushi Bay is an open-type bay with a deep and wide mouth facing the open sea. The size at sexual maturity and spatiotemporal patterns of reproduction of the kuruma prawn Marsupenaeus japonicus (Decapoda, Penaeidae) were examined and compared between these two regions. In the Yatsushiro Sea, the size at sexual maturity was estimated to be 131 mm body length. However, the estimated size at sexual maturity was considerably larger (154 mm) in Shibushi Bay. The spawning season of M. japonicus was estimated to continue from April to September in the Yatsushiro Sea, whereas it was estimated to be longer in Shibushi Bay, from March to November. It is believed that the warm water temperature due to the strong effect of the Kuroshio Current prolonged the spawning season of M. japonicus in Shibushi Bay. The spawning grounds were estimated to be in areas deeper than 10 m in the Yatsushiro Sea and deeper than 20 m in Shibushi Bay. In Shibushi Bay, body size distribution of mature females was considered to be less affected by water depth in comparison with the Yatsushiro Sea, although older mature females larger than 200 mm body length also spawned outside of the bay.  相似文献   
37.
以福建冬季海上筏式吊笼养殖的仿刺参为对象,采用传统海带饲料和市面销售的凝胶状海参配合饲料对三种规格的仿刺参幼参(平均体质量分别为105.57、73.15和52.89 g)进行了为期60 d的投喂试验,比较了两种饲料对仿刺参幼参生长的影响。结果表明,传统海带饲料投喂组大、中、小三种规格仿刺参的特定生长率分别为(0.69±0.04)、(0.87±0.05)和(0.99±0.02)%·d-1,凝胶状海参配合饲料投喂组的特定生长率分别为(0.65±0.03)、(0.86±0.05)和(0.81±0.10)%·d-1。传统海带饲料投喂组小规格仿刺参的平均个体增重率和特定生长率均显著大于凝胶状配合饲料投喂组(P0.05),而两种饲料投喂组大、中规格间的差异不显著。因此,传统海带饲料可用于仿刺参海上筏式吊笼养殖生产,而凝胶状海参配合饲料可作为传统海带饲料的辅助饲料。  相似文献   
38.
将体重为(65.26±4.37)g的刺参分成3组(A组为室内低温养殖,B组为夏眠30d后室内低温养殖,C组为夏眠60d后室内低温养殖),在不同温度条件下养殖120d,期间多次取样分析和比较刺参生长状况和体壁成分的变化。刺参夏眠期体质量显著下降,夏眠后体重增加明显。A、B、c三组刺参的特定生长率分别为-0.03%、0.27%、0.32%/d,存活率分别为91.67%、71.43%、53.57%,说明低温度夏虽然不能促进生长,但成活率高。刺参体壁主要营养成分含量由高到低依次为水分、粗蛋白、灰分、总糖和粗脂肪。养殖30d后,夏眠组与室内低温组相比,粗蛋白和粗脂肪含量增加,水分、灰分和总糖含量减少。实验结束时,A、C两组刺参体壁各营养成分与实验开始时无显著性差异(P〉0.05);B组除粗脂肪含量显著低于实验开始时(P〈0.05)外,其他体壁营养成分无显著性差异(P〉O.05)。研究表明,高温季节低温饲育并不能解除所有刺参夏眠;刺参经历夏眠蛰伏后有一个体重快速增长期;刺参在体重快速增长的同时,体壁营养成分含量无显著性变化。  相似文献   
39.
本实验旨在研究生长中期鲈鱼对饲料L-异亮氨酸的需要量。选取初始体重159.33±1.20g的鲈鱼为实验对象,在基础饲料中梯度添加晶体L-异亮氨酸,配制出异亮氨酸实测含量分别为0.72%、1.11%、1.53%、1.93%、2.31%和2.72%的6种饲料,在海水浮式网箱中进行10周养殖实验。实验结果表明,随饲料中L-异亮氨酸含量的升高,鲈鱼增重率(WGR)、饲料效率(FER)及蛋白质沉积率(PPV)均呈现先上升后下降的趋势,各组间差异显著(P<0.05),且在1.93%L-异亮氨酸饲料组出现最大值,分别为108.55%、0.89、和37.57%。饲料中L-异亮氨酸含量对存活率(SR)、摄食率(FI)、肝体比(HSI)、脏体比(VSI)、肥满度(CF)、体组成和肌肉氨基酸组成均无显著影响(P>0.05)。肝脏谷草转氨酶(GOT)、谷丙转氨酶(GPT)活力随饲料中L-异亮氨酸含量的升高呈现先上升后下降的趋势,各组间差异显著(P<0.05)。饲料中L-异亮氨酸含量对血清甘油三酯(TG)含量有显著影响(P<0.05),在L-异亮氨酸含量为1.93%时达到最大值,显著高于0.72%和1.11%组(P<0.05),但与其它各组差异不显著(P>0.05)。饲料中L-异亮氨酸含量对血清谷草转氨酶(GOT)、谷丙转氨酶(GPT)活力、血清总胆固醇(TC)含量无显著影响(P>0.05)。以增重率(WGR)和蛋白质沉积率(PPV)为评价指标,得出生长中期鲈鱼对饲料中L-异亮氨酸的需求量分别为1.88%和1.84%饲料干重,占饲料蛋白质的4.41%和4.32%。  相似文献   
40.
A feeding trail was conducted to evaluate the effect of lowering dietary fishmeal (FM) levels while increasing levels of dehulled soybean meal (SBM) on growth, nutrient utilization and body composition of juvenile kuruma shrimp, Marsupenaeus japonicas. Five experimental diets were formulated to be isoenergetic, isolipidic and isonitrogenous with decreasing FM levels from 40 to 16% while increasing SBM from 0 to 33% respectively. Quadruplicate groups of shrimp (initial wt = 1.5 g) were fed the test diets for 56 days under the flow‐through system. There were no significant differences in final weight (g) and specific growth rate (SGR, % day) among shrimp fed FM40, FM34, FM28 and FM22 diets respectively. Growth parameters significantly decreased in shrimp when fed FM16 diet, which was the lowest level of FM. Feed intake was positively correlated with the SGR of shrimp, and the lowest one was found in shrimp fed FM16 diet. Protein gain and retention, whole body lipid, arginine and methionine significantly decreased in FM16 fed group. Thus, it is concluded that dietary FM could be reduced down to 22% with SBM without compromising growth, nutrient utilization and retention, and whole body composition of kuruma shrimp.  相似文献   
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