| 摘要: |
| 在三疣梭子蟹(Portunus trituberculatus)的单体筐养养殖系统中, 试验了生态掩体(砂盒)中不同的砂粒粒径大小以及砂层厚度对梭子蟹幼蟹摄食行为与生长特性的影响。砂粒粒径设三个水平,分别为: >2mm、<0.2mm 以及混合砂; 砂层厚度有0cm、2cm、5cm、8cm 四个水平。试验共进行6天, 结果表明: 砂粒粒径及砂层厚度对梭子蟹幼蟹的摄食与生长都有明显的影响。从砂粒粒径看, 幼蟹在细砂(SPS)中挖洞休息, 蟹体与砂面呈30—45°角, 仅露眼睛及触角在外。一天内有3—6 次进食,总进食时间为(142.7±22.52)min, 在摄食次数、总进食时间、平均摄食量[(0.2427±0.0137) g/gBW]、以及蜕皮及成活率都远高于其它粒径组, 该组中幼蟹的体重增长最快, 增加了(0.814±0.113)g, 增长率为91.5%±3.43%; 而该组的饵料系数(FCR)最低为1.17±0.11。因此, 筐养养殖系统砂掩体的砂粒粒径最好为0.2 mm 以下。砂层厚度也有类似结果, 5 cm 以上厚度养殖效果最佳。平均摄食量为(0.2087±0.0046) g/gBW, 该厚度下, 幼蟹无死亡、100%蜕皮, 体重也增加最快, 增加了(0.791±0.121)g, 增长率为88.9%±3.74%, 饵料系数(FCR)达到1.37±0.23, 表明筐养系统掩体中砂层厚度要在5 cm 以上。三种保护性酶类(SOD, POD, CAT)活性随着砂粒粒径变小和砂层厚度增加而降低, 而消化酶类(淀粉酶、蛋白酶、脂酶)活性则表现与保护性酶类相反特性。从两类酶的活性变化也能证实, 在优选条件下(细砂、厚度>5 cm), 幼蟹所受的胁迫在降低。 |
| 关键词: 三疣梭子蟹 单体筐养养殖系统 砂粒粒径 砂层厚度 摄食行为 生长 |
| DOI：10.11693/hyhz20140800212 |
| 分类号: |
| 基金项目:宁波市海洋蟹类产业科技创新团队项目资助, 2011B81003 号; 国家自然科学基金项目资助, 41276123 号。 |
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| GRAIN SIZE AND THICKNESS OF SAND BOTTOM AFFECT THE GROWTH OF SWIMMING CRAB PORTUNUS TRITUBERCULATUS IN SINGLE-CRAB BASKET-CULTURE SYSTEM |
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XU Yong-Jian1, SHENTU Ji-Kang1,2, DING Zhang-Ni1
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1.School of Marine Sciences, Key Lab of Applied Marine Biotechnology of MOE, Ningbo University, Ningbo 315211, China;2.Ningbo Academy of Ocean and Fishery, Ningbo 315010, China
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| Abstract: |
| Effects of sand grain size and thickness of sand bottom on feeding behavior and growth characteristics of swimming crab Portunus trituberculatus in single-crab basket-culture (SCBC) system were investigated in four levels in grain size (diameter <0.2 mm to >2 mm) and in thickness (0 to 8 cm). The results show that the effect of sand grain size was obvious as the juveniles preferred to fine-grained sand (< 0.2 mm) for digging and rest in a hole for daily feeding 3—6 times [total (142.7±22.52) min] at food ration of (0.2427±0.0137) g/gBW, reaching best body weight gain [(0.814±0.113) g] in rate of 91.5%±3.43% and feed conversion ratio (FCR) at (1.17±0.11). In the sand bottom thickness, 5-cm thick or thicker was ideal, under which food ration was 0.2087±0.0046 g/gBW, no death, 100% moulting rate, body weight gain (0.791±0.121) g at 88.9%±3.74% in rate, and FCR at (1.37±0.23). In addition, activities of protective enzymes (SOD, PO, CAT) decreased with the sand coarseness while those of digestive enzymes (amylase, protease, lipase) were the opposite. Therefore, fine-grained sand bottom in thickness of at least 5 cm is suggested for cultivating the species. |
| Key words: swimming crab Portunus trituberculatus single-crab basket-culture (SCBC) sand size sand depth feeding behavior growth |
