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141.
142.
鲍是重要的海珍品,羊鲍(Haliotisovina)是主要生活在热带岩岸潮间带大型经济鲍类底栖动物。为了研究南海岛礁羊鲍资源及其栖息环境,我们在宣德群岛的永兴岛和七连屿,永乐群岛的羚羊礁、甘泉岛和晋卿岛进行了羊鲍资源分布及其栖息水环境研究。按照《海岛调查技术规程》中潮间带岩岸大型底栖生物调查方法,对羊鲍进行取样调查。按照《海洋调查规范第4部分:海水化学要素调查》(GB T 12763.4-2007),对羊鲍栖息地水环境的总无机氮、活性磷酸盐、悬浮物和叶绿素a等海水化学要素进行分析。结果表明,羊鲍在永乐群岛和宣德群岛都有分布,这些岛礁按永兴岛、七连屿、羚羊礁、甘泉岛和晋卿岛的顺序,分布密度依次增加,个头大小依次增大,总体来说羊鲍资源量小,有的岛礁海区几乎绝迹,亟需开展生态增殖和资源养护研究工作。水质调查表明,除永兴岛站位的悬浮物指标因填海作业未达标外,各站位的水质指标均达一类水标准且具有一定稳定性。因此,尽管南海岛礁受人类活动的影响,但该海域仍适合羊鲍栖息,是羊鲍资源养护、底播生态增殖和生态养护的适宜场所,符合建立海洋保护区的国家水质标准和环境条件。  相似文献   
143.
李进寿  卢斌  王波  柯才焕 《台湾海峡》2011,30(3):405-411
杂色鲍的免疫机能主要是由血细胞以吞噬的方式来完成.本研究将杂色鲍分别暴露在1、2、5Ixg/cm3不同含量氯霉素的水体中60d(每天暴露4h),检测其主要免疫指标的变化.实验结果表明,经氯霉素暴露实验后,杂色鲍的主要免疫指标出现了下降.对照组与各药物含量组(1、2、5μg/cm3)中杂色鲍血细胞对溶藻弧菌的吞噬率分别为89.83%±3.66%、75.33%±4.89%、68.67%±5.05%和37.00%±9.21%;其吞噬指数分别为3.84±0.27、2.54±0.35、2.12±0.47和1.18±0.32;其血细胞密度分别为(2.72±0.33)×10’、(1.87±0.09)×10^7、(1.46±0.17)x10^7、(1.03±0.14)×10^7个/cmA^3.对照组与各药物含量组在水温3l℃高温胁迫下杂色鲍半致死时间(,Jk)分别为10、8、6、4h.各实验组的壳长、体重生长率、成活率与对照组比较,高含量组均显著小于对照组.含量为lμg/cm^3和2μg/cm^3的氯霉素暴露对杂色鲍的生长有轻微的促进作用.各实验组酸性磷酸酶(ACP)、碱性磷酸酶(AKP)、超氧化物歧化酶(SOD)的酶活指标变化与氯霉素的暴露含量无明显相关性.  相似文献   
144.
对寄生在九孔鲍 (HaliotisdiversicoloraquatilisReeve)贝壳上的凿贝才女虫 (Polydoraciliata)进行了观察 ,将其发育过程分为卵、胚胎、幼虫和成虫 4个阶段 ,并对这 4个阶段的形态结构进行了描述和讨论。由于凿贝才女虫寄生 ,九孔鲍贝壳内侧形成弯曲的管道和隆起 ,其外套膜被破坏 ,严重影响了九孔鲍生长 ,甚至导致其死亡。  相似文献   
145.
The microsatellite-enriched library was constructed using magnetic bead hybridization selection method, and the microsatellite DNA sequences were analyzed in Pacific abalone Haliotis discus hannai. Three hundred and fifty white colonies were screened using PCR-based technique, and 84 clones were identified to potentially contain microsatellite repeat motif. The 84 clones were sequenced, and 42 microsatellites and 4 minisatellites with a minimum of five repeats were found (13.1% of white colonies screened). Besides the motif of CA contained in the oligoprobe, we also found other 16 types of microsatellite repeats including a dinucleotide repeat, two tetranucleotide repeats, twelve pentanucleotide repeats and a hexanucleotide repeat. According to Weber(1990), the microsatellite sequences obtained could be categorized structurally into perfect repeats (73.3%), imperfect repeats(13.3%), and compound repeats (13.4%). Among the microsatellite repeats, relatively short arrays (< 20 repeats) were most abundant,accounting for 75.0%. The largest length of microsatellites was 48 repeats, and the average number of repeats was 13.4. The data on the composition and length distribution of microsatellites obtained in the present study can be useful for choosing the repeat motifs for microsatetlite isolation in other abalone species.  相似文献   
146.
李进寿  陈军  唐艳霞  柯才焕 《台湾海峡》2010,29(4):460-465,593,593
利用流式细胞仪(FCM)技术检测了杂色鲍血细胞在体内和体外对不同含量荧光微球悬液的吞噬率.其结果表明体内注射法测定吞噬率的方法不可行.在体外吞噬中,当荧光微球含量为血细胞含量的68.2倍时吞噬率达98.43%±1.27%,随着荧光微球含量的降低血细胞吞噬率也随着降低.当荧光微球含量为血细胞含量的6.82倍时吞噬率为63.45%±6.05%,以这一含量进行血细胞吞噬率的测定比较恰当.利用这一含量测定了正常鲍与经过低盐(S=18)海水胁迫24 h后鲍的血细胞吞噬率的变化,正常鲍的吞噬率为68.71%±10.05%,经低盐海水胁迫后鲍的吞噬率为49.49%±10.18%,吞噬率出现了显著的下降(p〈0.05).实验结果表明利用流式细胞仪技术相比传统的显微镜镜检记数法检测杂色鲍血细胞吞噬率更为方便可靠.  相似文献   
147.
We investigated the effect of tributyltin (TBT) exposure on the concentration of malondialdehyde (MDA) and the activity levels of the superoxide dismutase (SOD), catalase (CAT), and acid and alkaline phosphatase (ACP and AKP) enzymes in the small abalone, Haliotis diversicolor supertexta. We collected samples of the hepatopancreas and hemolymph 2, 6, 24, 48, 96, and 192 h after exposure to 0.35 μg (Sn)/L TBT. In the hepatopancreas, ACP activity was significantly higher in animals exposed to TBT 2, 24, and 96 h post-exposure compared with the control animals. AKP activity was also higher after 2 h, but SOD and CAT activity was unchanged. The concentration of MDA in the hemolymph was significantly higher than the control animals 2 and 6 h post-exposure. In the hemolymph of animals exposed to TBT, ACP activity was significantly lower than in the control animals 192 h post-exposure, whereas AKP activity was significantly lower 2 and 192 h post-exposure. Hemolymph SOD activity and levels of MDA were significantly lower than in the control animals 24 h after exposure but significantly higher after 96 h. Our results demonstrate that exposure to TBT cause rapid changes in ACP and AKP activity as well as altering the concentration of MDA in the hepatopancreas and hemolymph. SOD and CAT do not appear to be involved in the detoxification of TBT in the hepatopancreas of small abalone.  相似文献   
148.
We conducted a preliminarily study on the effects of dietary guaiacol on growth performance of abalone, Haliotis discus hannai Ino. Seven semi-purified diets were formulated with graded levels of guaiacol (0, 5, 10, 50, 100, 500, and 1 000 mg kg−1). Abalone (initial weight: 0.29 ± 0.01 g; initial shell length: 8.55 ± 0.27 mm) were fed with these diets in a re-circulated water system for 152 days. Guaiacol significantly improved the specific growth rate (SGR) (P<0.05); excessive dietary guaiacol (1 000 mg kg−1) led to significantly high mortality (P<0.05), and lipid content in the soft body increased significantly after dietary guaiacol (P<0.05). Activities of catalase and phenoloxidase (PO) in the viscera were significantly stimulated by dietary guaiacol (P<0.05). Broken-line analysis based on SGR indicated that the minimum dietary guaiacol for the optimal growth of juvenile abalone is 15.43 mg kg−1.  相似文献   
149.
As the most widely used plasticizers in the world, phthalate esters (PAEs) are potential endocrine disruption compounds (EDCs). In the present study, the toxicity of dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), di (2-ethylhexyl) phthalate (DEHP) on embryogenesis and larvae development of the marine univalve Haliotis diversicolor supertexta was examined in laboratory. The results show that the malformation of embryos appeared during the experiment, such as embryos died or lysed, small transparent flocculent rings studded on the periphery of the embryo, and the larvae could failed to hatch. In embryo toxic test, embryos incubated at the highest concentration of DMP, DEP and DBP solutions showed significantly high abnormal rate compared with the control, while DEHP solutions displayed no significant difference. In larval toxic test, in all concentrations of DMP, DEP and DBP solutions, larval settlement rates were low significantly than that of the control. Similarly, DEHP solutions show nearly no effect on the larval settlement. The order of toxicity on embryos and larvae is DBP>DEP>DMP>DEHP. Being a simple and easy stimulation to indoor spawn, sensitive to environmental factors, and short culture time, the embryos of H. diversicolor supertexta can be used to indicate toxicity of the PAEs. Supported by National Natural Science Foundation of China (No. 40476057)  相似文献   
150.
The settlement substrates of nona-porous abalones (Haliotis diversicolor supertexta) are covered with biofilms in which several types of microorganisms coexist and interact. These microorganisms are usually important causes of juvenile abalone disease as well as organisms useful in promoting abalones’ adhesion. The bacterial community structure of the biofilms remains unclear. The aim of this research was to determine the genetic diversity and phylogenetic affiliation of the biofilm bacteria. Total DNA of b...  相似文献   
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