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1.
温度对魁蚶稚贝潜沙能力及对多棘海盘车捕食魁蚶稚贝能力的影响 总被引：1，自引：1，他引：0
在实验室条件下,研究了温度变化(10、15、20、25和30℃)对魁蚶稚贝(壳长2~3 cm)潜沙能力,及多棘海盘车对魁蚶稚贝捕食速率的影响。结果发现,水温10℃时,魁蚶稚贝的初次潜沙时间(初潜时间)最长,潜沙率最低,分别为28.87 min、21.25%,且与其他温度处理组差异显著(P0.05)。20℃时,魁蚶稚贝初潜时间最短、潜沙率最高,分别为7.49 min、55.63%,可视为魁蚶稚贝的最适潜沙温度。多棘海盘车对魁蚶稚贝的捕食速率受温度影响显著,水温20℃时捕食速率最大,为5.28个/d,且与10℃、25℃处理组间存在明显差异(P0.05)。水温15~20℃时,多棘海盘车的捕食温度系数Q10为2.22,可视为其最适捕食温度。魁蚶稚贝的最适潜沙温度与多棘海盘车的最适捕食温度范围重叠。因此,在水温20℃左右进行魁蚶稚贝底播增殖时,也是多棘海盘车捕食速率的最高时期,应加强底播海区多棘海盘车的清除。 相似文献
2.
为探究不同粒径养殖底砂对方斑东风螺(Babylonia areolata)稚螺养成效果的影响,在微流水养殖系统中采用3种不同粒径养殖底砂(细砂1 mm、中砂2 mm和粗砂3 mm)进行了养殖对比试验,比较其对稚螺生长、消化、抗氧化的影响以及对底质氨氮、亚硝酸盐氮含量的影响。试验稚螺的初始体质量、壳高、壳宽分别为(0.263 3±0.0033)g、(10.67±0.11)mm、(7.06±0.15)mm,试验周期为30 d。结果显示：试验结束时,细砂组稚螺的体质量、壳高、壳宽分别为(0.560 3±0.026 3)g、(12.72±0.06)mm、(8.50±0.16)mm,存活率为(92.67±0.94)%,均显著高于中砂组和粗砂组(P<0.05);随着养殖时间的推移,中砂组和粗砂组稚螺的存活率逐步降低,试验结束时分别降至(58.22±4.57)%、(48.44±1.13)%;中砂组稚螺最终的体质量、壳高、壳宽分别为(0.452 0±0.024 6)g、(12.13±0.17)mm、(7.91±0.13)mm,粗砂组分别为(0.427 5±0.019 6)g、(12.26±0.0... 相似文献
3.
一、目前魁蚶保苗和中间培育方法魁蚶保苗是指把壳长500微米以上附着的稚贝,装袋出池下海,培养到0.5厘米商品苗的过程,即为保苗。而苗种的中间育成是指将壳长0.5厘米商品苗培养成壳长1～2厘米幼贝的过程,是保苗过程的延续,主要用于增养殖放流。 相似文献
4.
为实现脉红螺苗种的规模化生产,本实验通过对脉红螺幼虫培育、采苗、稚螺培育等方面的系统研究,探索了脉红螺苗种繁育过程中幼虫附着变态率低和饵料转换难的问题。结果显示:脉红螺浮游幼虫前期(0~12 d)生长较快,壳高平均日增长21.8μm;中期(13~18 d)生长较慢,壳高平均日增长3μm;后期(19~30 d)生长加快,壳高平均日增长46.8μm。用取自沉淀池中的新鲜海水对脉红螺浮游幼虫进行附着变态诱导,诱导第1天脉红螺浮游幼虫开始出现附着变态,第4天时,附着变态活动基本结束,附着变态率为40%。为变态后的稚螺投喂刚附着的长牡蛎和魁蚶稚贝,第1~8天,稚螺壳高平均日增长65.6μm;第9天开始,稚螺生长速度加快;第9~12天,稚螺壳高平均日增长136.4μm;第13~16天,稚螺壳高平均日增长307.3μm;第17~20天,稚螺壳高平均日增长445.8μm。研究表明,用取自沉淀池中的新鲜海水诱导脉红螺浮游幼虫的附着变态效果好,刚附着的长牡蛎稚贝和魁蚶稚贝可以作为脉红螺稚螺培育阶段的适宜饵料。 相似文献
5.
乐清湾塘养泥蚶的生长 总被引：8，自引：0，他引：8
1998年6月至2000年7月对浙江省乐清湾塘养泥蚶的生长进行了详细的观察。刚孵化变态的D形幼虫壳长92-100μm，经10d培育达到180.5-201.5μm，平均每日增长8.9-10.2μm；稚贝附着后16d平均壳长从191.3μm增长到634.1μm，平均每日增长27.7μm；出库稚贝放养于围塘内，培育9个月平均壳长达到8.34mm，成为商品贝苗，平均每月增长0.86mm，其中9－10月份增长可达1.65mm；再经15个月培育达到成品贝，平均壳长28.57mm，平均每月增长1.35mm。泥蚶是一种慢生型贝类。对室内浮游幼虫、稚贝、中间暂养贝苗、成蚶养殖期间的多项生长指标进行测量和称重，获得的相关关系非常显著。 相似文献
6.
文章研究了盐度胁迫下魁蚶(Anadara broughtonii)稚贝(壳长25~35 mm)血淋巴渗透压和鳃Na+/K+-ATP酶活力的变化。结果显示,突变胁迫下,盐度20、25、35、40组的稚贝血淋巴渗透压均在48 h内显著降低或波动升高后趋于稳定,盐度15组则需96 h完成波动调整。以日变幅5渐变至高盐40过程中,稚贝血淋巴渗透压在48 h内趋于稳定;低盐15组仅需72 h完成渗透压调节,调整时间显著小于突变组。盐度突降胁迫下,各处理组稚贝鳃Na+/K+-ATP酶活力12 h后显著升高,24 h分别达到最大值,随后快速回落并稳定在高于对照组水平;盐度骤升胁迫下,鳃ATP酶活力波动降低,在12~24 h达到最小值后稳定在低于对照组水平。低盐(15)和高盐(40)渐变组的鳃ATP酶活力变幅均小于突变组。盐度胁迫下鳃Na+/K+-ATP酶活力的响应方式不同,即低盐胁迫时活力增强,高盐胁迫时活力降低。采用盐度渐变的驯化处理更有利于魁蚶稚贝应对盐度胁迫。 相似文献
7.
实验室条件下,研究大竹蛏稚贝的潜砂行为及稚贝规格对潜砂的影响。结果表明,大竹蛏稚贝的潜砂行为可分3个阶段:准备期、潜砂期及结束期。大竹蛏稚贝在壳长3.00～8.50 mm内,规格对潜砂准备时间、潜砂时间及潜砂行为的影响极显著,随着规格变大其潜砂准备时间逐渐降低(10.7～4.0 s);潜砂时间则表现为先降后升,壳长(6.20±0.04) mm组的稚贝潜砂时间最短,约9.7 s;各规格组稚贝的潜沙率均为100%,壳长(5.18±0.11) mm组潜砂率100%且用时最短。建议在大竹蛏增养殖过程中,投放苗种规格宜大于5.00 mm。 相似文献
8.
采用单因素实验方法对双线紫蛤(Sanguinolaria diphos)幼贝的存活与生长进行了研究。实验设置了7个盐度梯度(10~40)、5个密度梯度(500~10 000 ind/m2)和5种底质类型(全细砂、90%细砂+10%细泥、80%细砂+20%细泥、70%细砂+30%细泥、全粗砂),研究了不同盐度、密度、底质对其存活、生长的影响。结果表明:盐度20、25和30组存活率、生长率差异不显著(P0.05);不同密度条件下幼贝存活率、生长率差异显著(P0.05);不同底质类型对幼贝生长影响差异明显。双线紫蛤幼贝最适生长盐度范围为20~25;最适养殖密度范围为500~1 000 ind/m2,最佳养殖底质为细砂底质。研究结果为双线紫蛤池塘人工增养殖提供参考。 相似文献
9.
魁蚶俗称赤贝,是一种底栖型的经济贝类,在我国近海有广阔增养殖前景。目前,魁蚶人工育苗技术尚不完善、出苗量低等问题,严重制约魁蚶增养殖业的发展。为解决魁蚶育苗技术问题,笔者曾先后两次进行魁蚶人工育苗试验,1992年在绥中县钅止锚湾利用对虾育苗室,65m3水体培育出壳长1mm稚贝7480万粒,平均单产115万粒/m3,2006年在锦州市经济开发区锦州市苗种繁殖中心育苗室,100m3水体培育出1mm稚贝2.3亿粒,平均单产230万粒/m3,现根据多年的实践经验,就育苗生产中几项技术探讨如下,以求对今后的育苗生产有所帮助。1水质水是魁蚶育苗中首要的问题,水质是… 相似文献
10.
硬壳蛤稚贝对淡水浸泡、干露和低温的耐受能力 总被引：6，自引：2，他引：6
试验表明:水温26～30℃,随着稚贝规格的增大,对淡水的耐受能力增加,壳长784μm的稚贝淡水浸泡30min无死亡,浸泡120min稚贝死亡率为23 3%;壳长1 32mm的稚贝浸泡3h无死亡,浸泡16h死亡率为100%。气温28～30℃,壳长为1 54mm的稚贝干露24h无死亡;干露36h和48h的死亡率分别为20 0%和63 3%。壳长6～8mm的稚贝0℃下22d无死亡,49d死亡率为70%;在-2 5℃下12d无死亡,34d死亡率为90%。硬壳蛤对低盐具有较强的耐受力,并具有较强的耐干露力。 相似文献
11.
More information on the habitat requirements of lamprey is needed to improve measures aiming at rehabilitation of lamprey populations. Knowledge on habitat requirements of subyearling lampreys is especially scarce. We studied substrate selection by subyearling lamprey during the first three months after hatching using aquarium experiments. Differences in substrate selection by different‐sized larvae older than one year and the substrate depth selection by large larvae were also studied. Prolarvae of an average total length (TL) of 6.9 mm actively selected substrates with existing holes. When lampreys reached TL of over 8.0 mm, they started to select substrates which enabled them to construct a burrow. Lampreys of that size avoided coarse sand and gravel without fine material. Natural gravel with fine material was a frequently selected burrowing substrate during the 10‐week experiment suggesting its importance for subyearling lampreys. Substrates where very fine sand prevailed were the most selected soft sediments by subyearling larvae. Larvae older than one year did not select clay as a burrowing substrate. Medium (TL 70–98 mm) and large (TL 110–146 mm) larvae preferred coarse organic matter to fine sand. Larvae older than one year (TL 80–110 mm) preferred the thickest layer of soft substrate (10 cm) available to thinner layers. 相似文献
12.
Abstract – In a medium-sized river in northern Finland, larval grayling shifted with growth from shallow habitats with slow velocities, fine substrata and abundant vegetation cover to deeper sites with swifter velocities, coarse substrata and sparse vegetation cover within 3 weeks. Small (17–21 mm) larvae preferred water depths 10–30 cm, substrata dominated by mud or sand (<2 mm), 10–70% vegetation cover and water velocities <10 cm · s−1 . Middle-sized (22–25 mm) larvae preferred 30–90 cm depths, sandy substrata, <40% vegetation cover and velocities <10 cm · s−1 . Large (26–31 mm) larvae preferred >50 cm depths, substrata dominated by sand or boulders, <20% vegetation cover and 10–50 cm · s−1 velocities. The strict habitat requirements of the smallest larval group suggest that these habitats, in particular, are important to the early survival of grayling. 相似文献
13.
Anya Epelbaum Christopher M Pearce Simon Yuan Nadia Plamondon Helen Gurney‐Smith 《Aquaculture Research》2011,42(7):975-986
The basket cockle, Clinocardium nuttallii, is a candidate species for aquaculture in British Columbia, Canada. Previous research on broodstock conditioning, embryonic development and larval rearing of C. nuttallii demonstrated the potential for reliable hatchery production of cockle seed. In this paper, we investigated the effects of culture density (50% and 150% bottom cover in a monolayer) and substratum (none and fine sand) on cockle seed survival, growth, behaviour and shell morphology to improve the efficiency of the nursery production phase. Low stocking density (50% cover) yielded a shell length increase from 3 to 7 mm over a 4‐week period. High stocking density (150% cover) negatively impacted some of the growth and condition parameters studied, but did not have a statistically significant effect on seed survival. Growing seed without substratum did not significantly affect seed survival or growth, but led to shell deformities (at shell length >15 mm) and lower burrowing rates when cockles were subsequently placed on sand. We recommend planting seed for grow‐out at a shell length not exceeding 15 mm. Acclimating seed to the substratum before planting may increase the burrowing rates, thereby reducing the risks of seed dislocation and mortality. Additional studies are required to determine optimal substratum acclimation times and techniques. 相似文献
14.
Qingzhi Wang Xi Xie Ming Zhang Weiming Teng Miao Liang Ning Kong Chao Wang Zunchun Zhou 《Fisheries Science》2017,83(4):619-624
We investigated the combined effects of temperature (23, 26, 29 and 32 °C) and salinity [15, 18, 21, 24, 27 and 30 practical salinity units (PSU)] on the growth and survival of juvenile ark shell Anadara broughtonii under hatchery conditions. Mortality, shell length and shell height were monitored for a period of 25 days in all exposure groups. Survival greater than 98% was observed in all treatment groups with no significant difference among treatment combinations. Absolute growth and specific shell length and height growth rate were significantly influenced by temperature and salinity. Growth of juvenile A. broughtonii increased with higher salinity and peaked at an intermediate temperature (26 °C). Optimal specific growth rates of 4.64 ± 0.04% day?1 by shell length and 4.76 ± 0.11% day?1 by shell height were observed at a combination of 26 °C and 30 PSU. This study enhances our understanding of the biology of A. broughtonii and determines ideal environmental conditions for pre-planting culture operations. 相似文献
15.
Alejandro Abarca Doris Oliva Pedro Toledo 《Journal of the World Aquaculture Society》2019,50(4):774-788
Studies under laboratory and field conditions have shown that juvenile Mulinia edulis clams measuring 5–15 mm are able to tolerate transfer times of over 24 hr and burrow successfully. Burrowing generally followed an asymptotic curve over time, with a rapid initial phase for smaller juveniles, which slowed over time. In laboratory conditions, at low temperatures (8°C), juvenile burrowing was initially rapid (50–70% at first 2 min). In summer temperatures (15.5°C), the burrowing capacity of three sizes of juvenile clams was tested. Size determines differences in burrowing dynamics, where juveniles of 8.9 mm shell length (SL) take longer to burrow than smaller juveniles (4.9 and 6.3 mm SL). For longer transfer times in laboratory conditions (>12 hr), burrowing was slower. The results indicate a faster burrowing rate in smaller (<10 mm) juvenile clams than in larger ones. Transfer times over 24 hr in field experiments show burrowing levels of over 50% after a 60‐min evaluation, with larger juveniles (>10 mm) requiring longer for burrowing. Based on our results, we suggest sending seeds out to grow in natural environments at SL <10 mm, temperatures below 12°C, and transfer times shorter than 12 hr. These results are valuable for improving future transfer techniques from hatchery to growout for small‐scale aquaculture of this new native species in South America. 相似文献
16.
《Aquaculture (Amsterdam, Netherlands)》2006,251(2-4):238-244
The sandfish, Holothuria scabra, is a heavily exploited sea cucumber species. Minimising stress in the transportation of hatchery-produced sandfish juveniles to release sites is critical for successful restocking. Replicate groups (n = 4) of 20 hatchery-produced juveniles (1–5 g) were held in plastic bags with oxygen under 6 transport durations (0, 2, 4, 8, 12 and 24 h), two media (water or saturated sponge), and two temperature regimes (ambient and cool). Subsequent deaths and sand burrowing of the groups in release chambers were monitored for 5 days. Juveniles eviscerated or died only in treatments at ambient temperature on sponge for 24 h. Oxygen consumption in bags was reduced at cool temperature. On the first day after release, the normal sand burrowing was suppressed in juveniles held for 12 and 24 h, suggesting that pre-release acclimation for 1 day at field sites would benefit restocking. After the initial ‘shock’ of transport, handling stress appeared to increase burrowing behaviour for several days. Hatchery-produced sandfish also proved hardy for transport in high densities (100 and 200 juveniles per bag) and transportation stress will be minimised in seawater held at cool, constant temperature. 相似文献
17.
大竹蛏生产性人工繁育试验 总被引：9，自引：1，他引：8
2007年对大竹蛏进行了生产性人工繁育试验。对亲本不同批次催产效果、不同规格亲本产卵差异、孵化密度进行了比较,研究了D形幼虫发育与温度的关系以及幼虫发育各阶段生长规律等,结果显示,大竹蛏属分批成熟、分批产卵的潜居性贝类,不同批次个体平均产卵量(36~118)×104cell,个体总产卵量294×104cell。壳长8~10 cm的亲贝产卵量大,催产效果好。受精卵适宜的孵化密度为5~10 cell/mL。在水温21~24.5℃条件下,D形幼虫经8~5 d生长,发育变态为附着稚贝。D形幼虫壳长日生长33.33±4.22μm,1 mm前的稚贝壳长日生长108.33±22.57μm,1~10 mm的稚贝平均旬生长量2.12 mm,10.4~30.6 mm的苗种平均旬生长量为2.02 mm。当水温下降到15℃后,大竹蛏苗种生长滞缓。2007年培育出壳长11.52±0.27 mm的稚贝2 165×104cfu,平均成活率12.1%。 相似文献
18.
Hui Wu Maohua Li Rukui Zeng Xiaoshuai Liu Kun Yang Zhaobin Song 《Aquaculture Research》2020,51(7):2790-2798
It is advantageous for fish to choose different substrate types and brightness based on their current life cycle stage, foraging requirements, predator avoidance and water conditions. We determined the substrate type and brightness preference of hatchery‐reared and wild juvenile Schizothorax wangchiachii and Percocypris pingi under laboratory conditions. Individuals and groups were exposed to four kinds of substrate types (sand: diameter < 1 mm, small gravel: diameter approximately 2–3 cm, large gravel: diameter approximately 10–15 cm, sand and medium gravel mix: diameter approximately 4–7 cm) and two kinds of substrate brightness (black and white). The results showed that hatchery‐reared and wild S. wangchiachii and P. pingi significantly preferred large gravel and black substrates regardless of the number of fish (p < .05). P. pingi had a significantly higher preference for black substrate than S. wangchiachii both in hatchery‐reared and wild individuals (p < .05). Hatchery‐reared and wild individuals of the two species shared a preference for large gravel and black substrates suggesting that substrate preferences might be genetically based. The findings in the present study could be used to improve the rearing conditions for the two species in hatchery and thereafter to enhance its adaptability after releasing to the wild. 相似文献
19.
- 1. The vertical and horizontal distribution of unionoid mussels (Pronodularia japanensis) were examined in spring, late summer and winter for different size classes, including juveniles (<20 mm) and large adults (>50 mm), in an agricultural drainage channel in Central Japan.
- 2. A large number of small‐sized juveniles were found at the surface (0–3 cm depth) in spring, whereas approximately half of the adults remained in the deep layer (3–8 cm depth). Most individuals were found in the surface layer irrespective of size classes in summer, and approximately 70% of all individuals descended to the deep layer in winter.
- 3. Horizontal distribution did not substantially change across seasons and high density patches were consistently found in the areas where substrate appeared to be stable or hydraulically sheltered. Spatial distribution of small juveniles was relatively well predicted by the abundance of adults.
- 4. The size–frequency distribution was multi‐modal in three seasons and estimated numbers of newly recruited juveniles were highly variable in recent years, suggesting that juveniles were rarely found owing to irregular reproduction and/or recruitment not the overlooked habitat preferred by small‐sized juveniles.
- 5. As P. japanensis is characterized by the behaviour of burrowing down to a depth of ～10 cm, maintaining the processes of sediment deposition appears to be one of the critical criteria for the conservation of mussel habitats in agricultural drainage channel systems, which are commonly lined with smooth concrete materials. Copyright © 2010 John Wiley & Sons, Ltd.
20.
The present study was conducted to develop the hatchery technology for seed production of the widely exploited commercial sea cucumber Holothuria spinifera Theel 1886, to facilitate an effective stock enhancement programme. Broodstock collected by skin divers were used for spawning trials. The embryonic and larval stages were similar to other aspidochirotes. The larval survival rate was 43.5% on day 9, which decreased to 18.3% nearing metamorphosis on day 13, the growth rate was 48 μm day−1 and the settlement rate was 3.5%. Algamac® used to induce settlement also served as the food source for the early settled juveniles, followed by Sargassum spp. extract (<40 μm) for the first month. Sargassum spp. powder along with fine sand (1:1) was given to juveniles >20 mm. Addition of Spirulina spp. along with Sargassum spp. powder and fine sand (0.5:1:2) enhanced the growth rate of the juveniles. In the hatchery, the juveniles attained an average size of 1, 30 and 48 on 20, 80 and 120 days respectively. 相似文献