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1.
采用在基础饲料中分别添加0、130和260 mg/kg的合成虾青素配制成3种粗蛋白和粗脂肪含量分别为42%和16%的等氮等脂的中华绒螯蟹(Eriocheir sinensis)育肥饲料(分别记为饲料1、2和3), 以中华绒螯蟹商业育肥饲料作为饲料4, 分别投喂4组雌蟹(每个饲料组3个重复水槽, 每个水槽中12只蟹), 进行为期60d的室内养殖实验, 以探讨添加合成虾青素对中华绒螯蟹成体雌蟹性腺发育、色泽及抗氧化能力的影响。结果显示: (1)实验进行到30d和60d, 在饲料中添加虾青素对雌体肝胰腺指数(HSI)和性腺指数(GSI)均无显著影响(P>0.05)。(2)性腺、肝胰腺和头胸甲中的总类胡萝卜素含量和红度值(a值)均以饲料3组最高, 性腺亮度值(L值)和黄度值(b值)以饲料1组最高(P<0.05); 饲料2组头胸甲的b值最高, 饲料1组最低(P<0.05)。(3) 饲料1组中华绒螯蟹血清过氧化物酶(POD)活性显著高于其他组, 饲料4组的过氧化氢酶(CAT)、谷胱甘肽还原酶(GR)、乳酸脱氢酶(LDH)、总抗氧化能力(T-AOC)、丙二醛(MDA)和乳酸(LD)含量最高(P<0.05); 肝胰腺中的SOD、T-AOC、GSH-Px和GR活性均以饲料1组最高, 饲料2组最低(P<0.05)。(4) 饲料2组血清酸性磷酸酶(ACP)活性和血蓝蛋白(Hc)含量显著高于其他组, 其余各组间差异不显著。血清中的碱性磷酸酶(ALP)和γ-谷氨酰转移酶(γ-GT)活性和一氧化氮(NO)含量均以饲料4组最高(P<0.05), 肝胰腺中的ACP、ALP和γ-GT活性以饲料1组最高。综上, 在育肥饲料中添加合成虾青素对成体雌蟹性腺发育无显著影响, 但可显著提高头胸甲、肝胰腺和卵巢中的类胡萝卜素总量、色泽和抗氧化能力, 建议雌蟹育肥饲料中合成虾青素的含量为90 mg/kg左右。  相似文献   

2.
为研究饲料中添加鱼油和豆油对中华绒螯蟹(Eriocheir sinensis)成蟹生长、免疫、代谢和耐低氧性能的影响,配制了添加不同比例鱼油和豆油的3种蟹用饲料,添加3%鱼油饲料组、3%豆油饲料组、3%鱼油和豆油混合组(1∶1,质量比),将其分别投喂中华绒螯蟹115 d后测量蟹体重、壳长和壳宽的变化,再将其放入溶解氧(dissolved oxygen,DO)为(9.06±0.06)mg/L和(2.57±0.44)mg/L的水体中,测定其免疫、代谢指标及耐低氧性能的变化。结果发现:投喂添加3种不同油脂饲料的中华绒螯蟹各组间体重无显著性差异;低氧胁迫对中华绒螯蟹代谢指标影响较大;添加鱼油和豆油混合油饲料组中华绒螯蟹血细胞密度、血蓝蛋白含量及超氧化物歧化酶、酸性和碱性磷酸酶、乳酸脱氢酶的活性都为最高,说明鱼油与豆油混合添加对中华绒螯蟹免疫和抗氧化能力有促进作用,并增加其耐低氧能力。  相似文献   

3.
为研究长期不同水体盐度对中华绒螯蟹(Eriocheir sinensis以下简称河蟹)成体雄蟹渗透压调节和生理代谢的影响, 在不同水体盐度条件下(0、6、12和18)对河蟹雄体进行为期60d的养殖实验, 并分别检测其渗透调节及生理代谢相关指标。结果显示: (1)血清渗透压、Na+、Mg2+和Cl-含量随水体盐度上升而显著上升(P0.05), K+和Ca2+含量有上升趋势, 但各盐度组差异不显著(P0.05); 无论何组雄蟹, 其血清渗透压均显著高于对应的水体渗透压; (2)0组雄蟹后鳃Na+/K+-ATP酶活性显著高于其他组(P0.05), 其他各组间差异不显著(P0.05); (3)就血清生理代谢指标而言, 12组雄蟹血清中甘油三酯(TG)含量显著高于其他组(P0.05), 而尿酸(UA)、葡萄糖(Glu)、丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性相对较低; 所有组尿素(Urea)、碱性磷酸酶(ALP)含量差异不显著(P0.05); (4)就肝胰腺生理代谢指标而言, 6组肝胰腺MDA含量和-谷氨酰转肽酶(-GT)活力最低, 12组酸性磷酸酶(ACP)和-GT活性显著高于其他盐度组(P0.05)。因此, 适当提高水体盐度可提高河蟹成体雄蟹的血清渗透压及其主要离子含量, 同时降低其后鳃中Na+/K+-ATP酶活性。肝胰腺和血清代谢指标暗示12盐度组雄体的代谢水平相对较低, 具有较强的免疫性能和抗氧化能力。  相似文献   

4.
为研究叶酸和VB_(12)协同作用对中华绒螯蟹(Eriocheir sinensis)幼蟹生长、非特异性免疫和抗病力的影响,选取初始体重为(2.57±0.03)g的幼蟹600只,随机分成4组,每组5个重复,每个重复30只幼蟹,分别投喂对照组(不添加叶酸和VB_(12)),单一VB_(12)组(0.2 mg/kg),单一叶酸组(2.3 mg/kg)和联合处理组(0.2 mg/kg VB_(12)+2.3 mg/kg叶酸)的饲料8周。在养殖实验结束后,先统计成活率和称重,然后从每个处理组随机选取30只幼蟹,用2×10~8 CFU/m L的嗜水气单胞菌注射攻毒2周。实验结果表明:幼蟹的增重率、特定生长率、饲料效率和存活率在联合处理组最高,显著高于对照组(P0.05),但与单一叶酸或VB_(12)组相比不存在显著差异(P0.05)。联合处理组的血清酚氧化酶活性显著高于对照组(P0.05),但与单一叶酸或VB_(12)组也无显著性差异(P0.05)。同时,联合处理组的血清酸性磷酸酶、碱性磷酸酶、溶菌酶活性和血细胞总数等指标最高,其次是单一叶酸组和VB_(12)组,而对照组最低。投喂联合处理组饲料幼蟹的肝胰腺超氧化物歧化酶活性最高,而丙二醛含量和累积死亡率最低。以上结果表明,叶酸和VB_(12)对幼蟹的生长、生理代谢和免疫性能均可能有互补和协同作用,养殖生产中建议饲料中叶酸和VB_(12)添加量分别为2.3 mg/kg和0.2 mg/kg。  相似文献   

5.
饲喂蚕豆对草鱼抗氧化能力及免疫机能的影响   总被引:2,自引:0,他引:2  
投喂蚕豆100d左右,草鱼肌肉的弹性和咀嚼性增强,肌肉品质显著改善,此种模式养殖的草鱼俗称"脆肉鲩"。实验比较了投喂蚕豆与商用配合饲料的草鱼,在养殖过程中(30d、60d、100d)机体抗氧化能力及免疫机能的异同,以了解脆肉鲩肌肉品质改变过程中鱼体的生物学变化。实验结果表明,投喂蚕豆显著影响了草鱼血清总抗氧化能力(T-AOC)、血清丙二醛(MDA)含量及肝胰脏超氧化物歧化酶(SOD)活力,但对肝胰脏T-AOC、MDA含量、谷胱甘肽(GSH)含量及血清SOD活力无显著影响。实验30d和60d时,投喂蚕豆的草鱼机体抗氧化能力强于投喂配合饲料的草鱼,但实验100d时两种养殖模式的草鱼机体抗氧化能力无显著差异。投喂蚕豆对草鱼免疫机能有一定的影响,实验100d时,投喂蚕豆的草鱼血液红细胞数量(RBC)及白细胞数量(WBC)显著高于投喂配合饲料的草鱼。投喂蚕豆的草鱼血清TP、ALB、GLB含量在实验30d时显著低于投喂配合饲料的草鱼,在实验60d时与投喂配合饲料的草鱼无显著差异,在实验100d时又显著低于投喂配合饲料的草鱼。投喂蚕豆显著影响了草鱼脾指数及脾脏中免疫相关基因的表达,实验末期,在投喂蚕豆的草鱼脾脏中IL-1β、MHCⅡ、IFN-1、TNF-α的表达量显著高于投喂配合饲料的草鱼。以上结果表明,投喂蚕豆初期鱼体抗氧化能力增强,随着投喂时间的增加,鱼体抗氧化能力降低至与投喂配合饲料相当的水平;投喂蚕豆使草鱼产生了免疫应答。  相似文献   

6.
为了筛选适宜于养殖中华绒螯蟹幼蟹的饲料植物蛋白源,探究不同植物蛋白源饲料对幼蟹生长性能、氨基酸沉积率和抗氧化性能等方面的影响,以50%的鱼粉配制基础饲料(记为FM),分别采用30.5%发酵豆粕、32.5%豆粕、28%棉粕和39%菜粕替代基础饲料中鱼粉总量的50%,配制成4种等氮等能的饲料(分别记为FSBM、SBM、CSM和RSM),投喂初始体重为(0.249±0.003)g的中华绒螯蟹幼蟹8周。结果表明:(1)与FM组相比,FSBM、SBM和CSM组的增重率、特定生长率、饲料系数、蛋白质效率和蛋白质沉积率均没有显著性差异;RSM组的增重率与FM组相比差异不显著(P>0.05),但显著低于SBM组(P < 0.05),而其饲料系数则显著高于FM、FSBM及SBM组(P < 0.05),蛋白质效率显著低于其他各组(P < 0.05),蛋白质沉积率显著低于SBM和CSM组(P < 0.05)。(2)不同植物蛋白组的总必需氨基酸沉积率和FM组相比差异不显著(P>0.05),而RSM组总必需氨基酸沉积率显著低于FSBM和CSM组(P < 0.05)。(3)与FM组相比,不同植物蛋白组蟹的血清和肝胰腺中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)活性和肝胰腺丙二醛(MDA)含量并没有显著的影响,而RSM组血清丙二醛(MDA)含量显著的高于其他各组(P < 0.05)。结果表明,在幼蟹饲料中,豆粕、发酵豆粕和棉粕替代基础配方中鱼粉的50%后并未对幼蟹的生长性能、氨基酸沉积率及抗氧化能力造成负面的影响,发酵豆粕、豆粕和棉粕可以作为替代鱼粉的适宜蛋白源,且添加水平约在30%左右。菜粕替代后降低了饲料的利用和氨基酸沉积效率,这可能是由于菜粕的蛋白质消化率低、含有相应的抗营养因子和添加水平过高所致,建议使用前应适当进行脱毒处理,并与或和其他植物蛋白配伍使用。  相似文献   

7.
研究采用雨生红球藻(Haematococcus pluvialis)藻粉作为天然虾青素源, 配制4种不同虾青素含量(含量分别为0、26.60、41.62和81.37 mg/kg)的饲料(记为饲料1#—4#), 对三疣梭子蟹(Portunus trituberculatus)雌体进行为期45d的育肥实验, 研究其对雌蟹卵巢发育、色泽、抗氧化能力、免疫性能和生化组成的影响。结果表明: (1)育肥饲料中虾青素含量对雌蟹性腺指数(GSI)和肝胰腺指数(HSI)均无显著影响。(2)肝胰腺、卵巢和头胸甲中的总类胡萝卜素含量、红度(a*)值和黄度(b*)值均随饲料虾青素含量的升高而升高, 而3种组织的亮度(L*)值呈显著下降趋势(P<0.05)。(3)对抗氧化指标而言, 虾青素添加组(饲料2#—4#)血淋巴超氧化物歧化酶(SOD)和过氧化物酶(POD)活力均显著低于无虾青素组(饲料1#); 血淋巴中的总抗氧化能力(T-AOC)、谷胱甘肽过氧化物酶(GSH-Px)及肝胰腺中的SOD和T-AOC活力均随饲料中虾青素水平升高而上升, 而血淋巴和肝胰腺中的丙二醛(MDA)含量呈下降趋势。(4)对免疫指标而言, 血淋巴和肝胰腺中的酸性磷酸酶(ACP)活力均在饲料4#组最高, 而饲料1#组血淋巴中的血蓝蛋白(Hc)含量显著高于其他组(P<0.05)。(5)对生化组成而言, 肌肉和肝胰腺中的总脂、总碳水化合物及卵巢中总脂含量均随饲料中虾青素含量的升高呈上升趋势, 饲料2#组卵巢中的总碳水化合物含量最高(P<0.05)。综上所述, 三疣梭子蟹雌体育肥饲料中添加虾青素对其卵巢发育无显著影响, 但可改善色泽和提高其抗氧化能力及可食组织中的总脂和碳水化合物含量, 三疣梭子蟹雌体育肥饲料中虾青素适宜含量为50 mg/kg饲料左右。  相似文献   

8.
为探讨植酸酶对中华绒螯蟹(Eriocheir sinensis)幼蟹生长、消化性能及物质利用率的影响, 设计了6种配合饲料, 以不含植酸和植酸酶的组别为对照组(C), 在含有10 g/kg植酸的饲料中, 分别加入0、500、1000、1500 U/kg的植酸酶, 分别记为P0、P500、P1000、P1500和P2000。投喂初始体重为(4.34±0.05) g的幼蟹, 56d后称重并取样分析。结果发现: P0幼蟹增重率、特定生长率、蛋白质效率低于对照组, 饲料系数则高于对照组(P<0.05); 幼蟹增重率、特定生长率、蛋白质效率随着饲料中植酸酶含量的增加而升高, 在P2000达到最高, 且该组的饲料系数最低(P<0.05); P1500和P2000全蟹体磷含量显著高于P0 (P<0.05); 在P2000中, 幼蟹肝胰腺中胰蛋白酶、淀粉酶以及肠道胰蛋白酶活力达到最高(P<0.05); 中华绒螯蟹蛋白质消化率和磷透析率随着饲料中植酸酶含量的增加而逐渐升高, 其中P2000显著高于P0(P<0.05), 与对照组无显著差异(P>0.05); P2000幼蟹的氮、磷保留率最高(P<0.05)。以上结果表明, 在含有植酸的饲料中添加2000 U/kg的植酸酶, 能够显著提高幼蟹的生长和胰蛋白酶活力, 进而提高幼蟹对蛋白质的利用率, 降低饲料系数。此外, 植酸酶的添加也能有效提高幼蟹体磷含量和氮/磷保留率。  相似文献   

9.
实验配制7种等氮(粗蛋白35%)、等脂(粗脂肪6%)的不同淀粉水平(4%、10%、16%、22%、28%、34%、40%)的饲料,投喂中华绒螯蟹(Eriocheir sinensis)幼蟹[初始均重(6.2±0.1)g]8周,通过生长和生理指标评价中华绒螯蟹幼蟹对饲料碳水化合物的利用能力。为避免互相残杀,河蟹采用静水单个养殖,每种饲料40只河蟹。玉米淀粉作为实验饲料碳水化合物主要来源。实验结果表明:饲料中34%—40%淀粉组的摄食率显著低于4%—16%组(P0.05)。随饲料中淀粉含量提高幼蟹的体重和壳长特定生长率也相应提高,34%淀粉组体重特定生长率显著高于4%淀粉组(P0.05),22%淀粉组的壳长特定生长率显著高于4%淀粉组(P0.05);饲料中淀粉含量的增加显著提高了饲料效率,且在40%淀粉组最高。饲料高淀粉可提高蛋白储积率,蟹的肝体比在16%淀粉组最低,而蜕壳率和成活率在该组最高。蟹体干物质、粗蛋白、粗脂肪和灰分在高饲料淀粉组较高。幼蟹胰蛋白酶活力在16%淀粉组最高(P0.05);肝糖原含量随饲料淀粉水平升高呈线性(y=0.2268x+17.256,R2=0.9453,n=7,P0.05)上升。通过二次多项式回归可以得出河蟹获得最大特定生长率时饲料淀粉的含量为25.6%。  相似文献   

10.
开展中华绒螯蟹(Eriocheirsinensis)生物学研究,对指导养殖具有重要意义.1993年6月20日购于上海市崇明县的仔蟹放养于湖北省保安湖渔场的一个试验塘(2330m2),每天投喂小杂鱼和螺蚌肉.在试验期间,河蟹成活率为18.6%.协方差分析表明,性别对各月体重与壳长、体重与壳宽及壳宽与壳长回归方程的截距和斜率均无显著影响(p>0.05);但是,两性数据混合后的不同月份间回归方程的截距却有显著差异(p<0.01).在每次取样时,雄蟹与雌蟹的壳长、壳宽及体重均不存在显著差异(p>0.05),这表明雄蟹与雌蟹可能具有相同的生长率.在各次取样时统计的性比(雄∶雌)均无异于理论值1∶1(X2检验,p>0.10).在九月中旬发现大部分雌蟹开始青春期蜕壳,在11月下旬雌蟹性成熟比例为88%,性成熟雌蟹壳长变幅为26.2-49.8mm,均值为34.1mm.  相似文献   

11.
The disease caused by parasitic dinoflagellates of the genus Hematodinium was found in the red Paralithodes camtschaticus and blue P. platypus king crabs from the Sea of Okhotsk. The hemolymph of diseased crabs was cream colored, opaque, and dense. Numerous dinokaryotic trophonts and multinucleate plasmodia of the parasite were revealed in the hemolymph and internals of diseased animals. The parasitic infection was recorded in females and juvenile males from August to mid-October.  相似文献   

12.
Conventional theory postulates that associations between marine macrophytes and animals are generally positive. This paper presents evidence, however, that a common species of green macroalga, Ulva lactuca (L.), is detrimental to estuarine invertebrates due to the production of toxic exudates and low oxygen tensions which occur in the seaweed beds at night. Bioassays of the responses of zoeae of five species of estuarine crabs (Callinectes sapidus Rathbun, Carcinus maenas L., Eurypanopeus depressus Smith, Neopanope texana savi Smith and Rhithropanopeus harissii Gould), using water in which Ulva lactuca was cultured for 24 h, produced 100% mortality after 22 days. No crabs survived the molt into megalopa. Hypoxic water, 0.5 ± 0.3 ppm oxygen, caused a decline in larval activity (movement), but there was no mortality over an 8-h period, Ulva-water purged to 0.4 ± 0.1 ppm oxygen caused 100% mortality in 13–40 min. These synergistic effects could be critical in estuaries where dense U. lactuca beds cause periods of low dissolved oxygen. We hypothesize larval recruitment may be limited in such systems, particularly in areas where flushing is poor.  相似文献   

13.
Of 188 Dungeness crabs, Cancer magister, 8 contained unidentified trematode metacercariae encysted in various components of the nervous system, including the thoracic ganglion, brain, lamina ganglionaris of the eyestalk, and major nerves arising from the thoracic ganglion. A single cyst was present in the available tissue sections of 7 of the crabs and no behavioral abnormalities were exhibited. One crab with multiple cysts in major nerves near the thoracic ganglion was markedly ataxic. The cysts and included worms distorted, compacted, and destroyed nervous tissue, and occupied most of the nerves where present. Host response was minimal, but some cysts invoked massive hemocytic accumulations near the infection site. Infections probably seriously affect nerve impulse transmission and accounts for the lethargic behavior of the crab with multiple cysts in major nerves. The present report is the first record of digenetic trematode infections in the Dungeness crab and the apparent restriction of the worm to nervous tissue is unusual if not unique in the Digenea. Because of the absence of grossly recognizable lesions and the small samples excised at necropsy, both the incidence and intensity of infection in Dungeness crab populations are almost certainly higher than indicted by our data.  相似文献   

14.
Terrestrial hermit crabs in the family Coenobitidae (genera Coenobita and Birgus) are distributed in tropical and subtropical regions. They occupy various habitats ranging from shore to inland forests, and the two shore‐dwelling species, Coenobita rugosus and C. violascens, possess different distributional characteristics on Ishigakijima Island, Ryukyu Archipelago, Japan. Coenobita rugosus is distributed throughout the coast of the island and is abundant in beach areas, whereas C. violascens has mainly been found in river mouth areas. However, very little is known about the habitats used by the early life stages of coenobitid crabs because identifying the species of recently landed early juveniles is difficult. We tested whether the species compositions of early juveniles of coenobitids differed between beach and river mouth sites on Ishigakijima Island. We collected and identified the early stage coenobitids using PCR–RFLP techniques. A total of 576 early juveniles of five Coenobita species were collected, of which 0.7% were C. brevimanus, 7.3% were C. cavipes, 0.2% were C. purpureus, 70.1% were C. rugosus, and 21.7% were C. violascens. The early juveniles of Birgus latro were not found. The early juveniles of C. rugosus occurred at both beach and river mouth sites, and they were abundant at beach sites. The early juveniles of C. violascens were only found at river mouth sites. These findings indicate that C. rugosus and C. violascens complete their life cycles on land near the localities where they land. The early juveniles of the inland‐dwelling species, C. cavipes, were also mainly collected from river mouth sites, which suggested that juveniles of C. cavipes selected landing sites near river mouth areas and then migrated into the inland forests, passing through riverside areas. Our results highlighted the importance of river mouth areas for recruitment to adult habitats by some coenobitid species.  相似文献   

15.
The symbiotic lifestyle is widespread among porcellanid crabs, which maintain ecological and co-evolutionary associations with annelid polychaetes, poriferans, cnidarians, echinoderms, gastropod mollusks, and other crustaceans such as shrimps and hermit crabs, among others. We investigated the ecological association between the hermit crab Dardanus insignis and the porcellanid Porcellana sayana, in southeastern Brazil. Porcellanid crabs, hermit crabs, and available shells were collected monthly from July 2001 to June 2003, with a shrimp boat equipped with two double-rig trawl nets. The majority of P. sayana specimens were collected in shells occupied by D. insignis (96.6%); a few were found in empty shells (3.4%). The catch of both symbionts and hosts increased with increasing depth, with the highest occurrence at 35 m. The P. sayana crabs of various sizes could be found solitary or forming aggregations of up to 14 individuals per host, showing no sex or size segregation. In spite of the high diversity of shell species occupied by the hermit crabs and also available in the field, only a few of them were also utilized by P. sayana. The majority (93%) of shells utilized by P. sayana also hosted other symbiont species, constituting the basis of extensive symbiotic complexes. Thus, the ecological relationship between D. insignis and P. sayana may be classified as a non-obligate and non-specific symbiosis that may also involve other facultative organisms such as sea anemones.  相似文献   

16.
17.
Fifty-three Tanner crabs with varying degrees of surface encrustations and internal invasion by Trichomaris invadens were necropsied, processed, and examined to determine the extent of internal tissue invasion and histopathological effects of the infection. Sufficient data were accumulated to provide some insight on the progression, but not the rate, of tissue invasion. The epidermis and subepidermal layers are invaded and virtually replaced by proliferating hyphae. The invasion then proceeds internally, predominantly via the connective tissue. Major muscles and blood vessels are invaded, then invasion of deeper organs, including the hemopoietic tissue, gastrointestinal tract wall, and wall of the heart follows. The eyestalk is infected, usually early in the disease, and the invasion follows a similar pattern to that in the cephalothorax. Massive invasion and destruction of the retina is the major pathological effect. The gill may also be involved, with destruction of the lamellar tissues and invasion and destruction of podocytes in the stem of the gill.  相似文献   

18.
In this paper the fishing grounds, fluctuations in catches, history of exploitation, classification, distribution, migration, life history and resource trends of the edible crabs of the waters around Hokkaido are discussed. The Hokkaido crab fisheries developed along with the canning industry and there is now an increasing demand for boiled crab. At first, the most popular species was the king crab, Paralithodes camtschatica, but as its numbers declined other species such as the horsehair crab, Erimacrus isenbeckii, the banasaki crab, Paralithodes brevipes, the snow crab, Chionoecetes opilio, and the red snow crab, Chionoecetes japonicus, became popular. This report is based on the results of the latest research into the ecology and resources of the Erimacrus isenbeckii and Paralithodes brevipes species, which are currently the focus of resource conservation in Hokkaido.  相似文献   

19.
Larval release, hatching rhythms and moult patterns were examined in a captive population of the subantarctic lithodid, Paralomis spinosissima from the South Georgia and Shag Rocks region. Larvae hatched throughout the year with the majority of females starting to release larvae at the end of the austral summer and beginning of autumn. Larval release continued over a period of up to 9 weeks with high variability in the numbers that hatched each day. A similar seasonal pattern to hatching was evident in the moulting of females. Intermoult period for two adult females (CL = 63 and 85 mm) ranged from 894 to 1,120 days while an intermoult period for males was estimated to be in excess of 832 days. The results are consistent with other species of Paralomis and are discussed in relation to physiological and environmental adaptations to the cold-water conditions south of the Antarctic Convergence.  相似文献   

20.
鲎具有极高的经济价值和科研意义。近年来由于过度捕捞和栖息地受损等原因,亚洲鲎种群数量正急剧下降。鲎漫长的生命周期使得鲎资源的保护和增殖迫在眉睫。生态位模型已经广泛应用于物种的潜在地理分布预测。基于实地调研数据和公开发表的北部湾中国海域中国鲎和圆尾鲎地理分布数据,运用MAXENT模型得到中国鲎和圆尾鲎在广西北部湾(中国部分)的栖息地适宜度指数(Habitat suitability index, HSI),确定了这两种稚鲎在北部湾中国海域潜在适生区。模型分析结果表明,潮间带坡度和地形指数是影响中国鲎分布的主要环境因子,而潮间带底质的有机物含量和植被指数是影响圆尾鲎分布的主要环境因子,根据研究结果建议在两种稚鲎适生区建立保护区,进行人工放流稚鲎,加强对海草和红树林的生态建设,进而促进鲎资源种群恢复和发展。  相似文献   

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