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31.
Parentage analysis is of vital importance for hatchery production and breeding programmes. Two multiplex PCR protocols including seven tropical spiny lobster (Panulirus homarus) microsatellites (Pho‐G06, Pho‐G25, Pho‐G53, Pho‐G62, Pho‐G74, Pho‐G89 and Pho‐G100) were introduced for parentage assignment. All loci were polymorphic with allele sizes from 113 to 337 base pairs (bp), observed alleles (k) from two to seven and polymorphic information content (PIC) of 0.25 to 0.73. Twenty‐four stage‐3 phyllosoma larvae (39 days posthatching) were collected for paternity exclusion study using selected microsatellites. Exclusion‐based parentage analysis unambiguously assigned 83% of fry (20 of 24) to a single female parent. Of ten putative female parents, five have contributed to the 20 allocated offspring, with one being true parent of 11. Four others were assigned to two or more potential female parents, probably due to genotyping error or the presence of null allele. The exclusion power (EP) for the seven loci varied between 13% and 54% with known genotypes of one parent (P1) and 19% and 71% for given the genotypes of both parents (P2). The theoretical combined parentage exclusion (cEP) power for all seven microsatellites was P1 = 95% and P2 = 99%. The power of discrimination for each locus varied between 0.18 and 0.86. This report presents the first study to utilize microsatellite markers for successful parentage assignment of P. homarus. The selected microsatellites provide a practical tool for parentage analysis in hatchery production of juveniles as well as in future commercial breeding programme of tropical spiny lobsters.  相似文献   
32.
An understanding of the effect of key intrinsic and extrinsic factors on the oxygen consumption of Panulirus homarus rubellus is imperative for the development of optimized transport, holding and growout protocols. This study investigated the effect of body weight, photophase, feeding and emersion on the oxygen consumption rate of P. h. rubellus . Body weight was positively correlated to both standard and active oxygen consumption (mg O2 h−1) while body weight was negatively correlated to mass-specific standard oxygen uptake (mg O2 g−1 h−1). Diurnal rhythm exhibited a strong effect on the lobsters' oxygen consumption, with average nighttime values 67% greater than those recorded during the day. This was related to activity driven by intrinsic nocturnal foraging behaviour. Feeding resulted in a classic specific dynamic action response, with postprandial oxygen consumption increasing to a peak before decreasing gradually to preprandial levels. Emersion caused a significant increase in oxygen consumption following re-immersion. Lobsters rapidly recovered to pre-emersion levels after 4 h following a 1-h emersion and after 13.3 h following an emersion period of 6 h. The implications of these results with regard to the holding/culture system and protocol design are discussed.  相似文献   
33.
The successful culture of the east coast rock lobster Panulirus homarus rubellus is reliant, among other factors, on the provision of optimal water quality for growth and survival. This study investigated the effect of temperature over a range of 9.7 °C (18.9 ± 0.7 °C to 28.6 ± 1.5 °C) on the growth and survival of juvenile (40.4 ± 9 mm CL; 63.64 ± 12.05 g) P. h. rubellus fed a diet of fresh mussel flesh. Specific growth rate (SGR) was significantly different between temperatures (p = 0.01), with the highest values recorded for the 24 and 28 °C treatments. There was no significant difference in moult increment (MI) between temperatures in terms of both an increase in weight (p = 0.83) and carapace length (p = 0.54). Intermoult period (IMP) differed significantly between temperatures (p = 0.0015) with mean IMP lowest at 24 °C, although not significantly different from the means of the 26 and 28 °C treatments. IMP was highest at 19 and 21 °C. Apparent feed intake was significantly different between treatments (p < 0.0001) and exhibited a strong positive correlation with increasing temperature (y = − 1.67 + 0.16x ; r2 = 0.81). Food conversion ratio (FCR) differed significantly between temperatures (p = 0.02) with 24 °C exhibiting the most efficient FCR. Results indicate that efficient growout of juvenile P. h. rubellus, in terms of both growth and food conversion efficiency, is obtainable at 24 °C.  相似文献   
34.
采用毒理学方法,在水温28.0~29.0℃下于0.5 m^3的圆形玻璃钢桶中,用氯化镉和氯化汞配成不同质量浓度的Cd^2+和Hg^2+试验溶液,研究Cd^2+和Hg^2+对体质量49.10~52.10 g波纹龙虾的毒性,用直线内插法求得Cd^2+和Hg^2+的半致死质量浓度及安全质量浓度。试验结果显示,Cd^2+对波纹龙虾的24、48、72、96 h半致死质量浓度分别是2.5169、1.3378、1.0445、0.9500 mg/L,安全质量浓度为0.0095 mg/L;Hg^2+对波纹龙虾的24、48、72、96 h半致死质量浓度分别是0.0560、0.0333、0.0246、0.0227 mg/L,安全质量浓度为0.000227 mg/L。Hg^2+对波纹龙虾的毒性作用强于Cd^2+的毒性作用。  相似文献   
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应用组织学和组织化学方法研究中国龙虾的消化道.消化道可分为前肠、中肠和后肠.前肠包括口、食道和胃,胃可分为贲门胃和幽门胃,贲门胃内有由几丁质齿、嵴和刚毛组成的胃磨,幽门胃内则有由几丁质板、衬垫及栉状刚毛组成的过滤器.组织学研究结果表明,消化道壁由粘膜层、结缔组织层、肌肉层和外膜构成;除中肠外,其余消化管壁上皮均覆盖有几丁质层;消化道上皮基本由单层柱状细胞构成;肌肉层从排列上可分为纵肌、环肌和放射肌,主要由平滑肌构成,其中食道壁肌肉为骨骼肌;外膜不明显.组织化学研究表明,消化道各段中,几丁质表层的多糖物质含量较多,结缔组织和粘液腺中的次之,中、后肠上皮细胞中含少量糖原;肌肉细胞内含丰富的蛋白质和部分脂类,结缔组织和各段上皮的含量次之.还探讨了中国龙虾消化道的结构与功能的关系.  相似文献   
38.
试验结果表明,波纹龙虾卵巢呈H状,位于消化道的背面,随着卵巢的发育颜色依次为乳白色、淡橙色、橙色和橙红色.卵子发生分为4个时期(8个亚期):增殖期(卵原细胞期)、卵黄合成前期(束状期、染色质核仁期)、卵黄合成期(油球期、卵黄板形成前期、卵黄板形成期、成熟前期)和成熟期;卵巢发育分为6个时期:增殖期、发育期、成熟前期、成熟期、排卵期和恢复期.  相似文献   
39.
波纹龙虾早期叶状幼体的培育及其形态观察   总被引:1,自引:0,他引:1  
为了探索波纹龙虾(Panulirus homarus)幼体培育新方法,并系统描述其幼体形态特征.在室内以5种不同的饵料组合投喂波纹龙虾早期叶状幼体.结果表明,扁藻(Platymonas sp.) 卤虫(Artemia salina)组的存活率和变态率最高,到48 d后,幼体存活率达25%,并25%的幼体能顺利完成6次蜕皮;卤虫组、角毛藻(Chaetoceros sp.) 卤虫组的存活率和变态率较低,没有幼体能顺利完成4次蜕皮.对叶状幼体的形态特征进行观察,发现刚孵出和蜕皮1次的叶状幼体无眼柄,第2次蜕皮后开始出现眼柄,第3次蜕皮后开始出现第4步足,第5次蜕皮后开始出现第5步足,在随后的几次蜕皮后,第4步足明显增长,第9次蜕皮后第4步足出现带有羽状刚毛的外肢.以扁藻 卤虫作为饵料时,波纹龙虾早期叶状幼体培育效果较好,并获得了脱皮9次的叶状幼体.  相似文献   
40.
3种消毒剂对中国龙虾的急性毒性试验   总被引:2,自引:0,他引:2  
采用高锰酸钾、甲醛和强氯精3种消毒剂对中国龙虾进行急性毒性试验。结果表明:高锰酸钾对中国龙虾的24、48、72和96h的LC50分别是4.49、4.44、4.39和4.22mg/L,安全浓度是1.32mg/L。甲醛对中国龙虾24、48、72和96h的LC50分别是135.19、125.22、125.22和121.79mL/m3,安全浓度为34.80mL/m3。强氯精对中国龙虾的24、48、72和96h的LC50分别为40.97,36.63,36.25mg/L和36.25mg/L。安全浓度为8.68mg/L。  相似文献   
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