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Cuixue Huang;Xiangxing Nie;Jie Wei;Yakun Wang;Kunhao Hong;Xidong Mu;Chao Liu;Zhangjie Chu;Xinping Zhu;Lingyun Yu; 《Aquaculture Research》2024,2024(1):8897473
The spectrum is a key environmental factor, and light-emitting diodes (LEDs) can influence the growth and development of crustaceans by altering the composition of the spectrum. This study conducted a 30-day experiment to investigate the effects of five LED spectra (red, yellow, blue, green, and white light) on the growth, antioxidant and immune enzyme activities, stress hormone levels, and the expression of α-amylase (α-AMY), ecdysone receptor (EcR) and retinoid X receptor (RXR) genes in juvenile redclaw crayfish (Cherax quadricarinatus). The results show that the survival rate of juveniles is markedly higher in the yellow and red-light groups than in the other three groups (P < 0.05). The green light group exhibits the lowest survival rate, yet it demonstrates the highest weight gain rate and specific growth rate. Regarding enzyme activity and hormone levels, the yellow light group shows the lowest malondialdehyde content, with higher superoxide dismutase and acid phosphatase activity than the other groups; no significant differences are observed in lysozyme activity among the groups (P > 0.05). The melatonin content in the green and blue light groups is significantly higher than that in the other three groups (P < 0.01). In terms of growth gene expression, the expression of α-AMY, EcR, and RXR in juvenile C. quadricarinatus is regulated by the spectrum. In conclusion, when raised under the yellow light spectrum, juvenile C. quadricarinatus displays elevated survival rates, rapid growth, and robust antioxidant and immune defenses. This study provides important technical parameters for optimizing and enhancing the industrial cultivation of juvenile C. quadricarinatus. 相似文献
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Xiao-Bing Wu Yi-Quan WangKai-Ya Zhou Wei-Quan ZhuJi-Shan Nie Chao-Lin WangWan-Shu Xie 《Biological conservation》2002,106(3):435-441
Chinese alligator (Alligator sinensis) is an endemic species in China. The likely extinction of it in the wild has been recognised. To prevent this species becoming extinct, the Anhui Research Centre of Chinese Alligator Reproduction (ARCCAR) was established in Xuanzhou, Anhui Province in 1979, where has been established the largest captive population of Chinese alligator (XZSP) in the world. Another farm (CXSP) was established by villagers in Changxin, Zhejiang Province. The results of an investigation of the two captive subpopulation structures by genetic analysis are presented in this paper. We examined the genetic variation in the two captive subpopulations using RAPDs. Thirty-one random primers were selected among 199 random primers screened. A total of 193 reproducible RAPD fragments were scored among 43 individuals, of which 21 (10.88%) were polymorphic. The genetic distances between 43 individuals ranged from 0 to 0.0376 with average of 0.0104±0.0055 S.E. The genetic similarity in CXSP (0.9948±0.0029 S.E.) was higher than that in XZSP (0.9894±0.0055 S.E.). The founder effect is a possible explanation for very low genetic variation in CXSP. Analysis of the RAPD data showed that the mean phenotypic band frequencies of each polymorphic loci was 0.6656±0.3730 S.E. The lowest phenotypic band frequency (0.0233) was found in four of those polymorphic loci. There was no genetic difference between the two subpopulations (Dij=0.0009). According to the dendrogram and the distribution of polymorphic fragments in two subpopulations, CXSP originated genetically from XZSP. This paper summarises a preliminary research on genetic structure in populations of Chinese alligator. Although there is higher genetic similary (0.9896±0.0055 S.E.) in captive population of A. sinensis, we did not determine whether or not loss of genetic variation had occurred in relation to a wild control population. The data of malformed offspring will be collected carefully, and wild samples be added to set up a control population in future study. 相似文献
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随着人民生活水平的提高,传统养殖品种市场行情一直走低,养殖效益日益下滑,调整养殖品种结构已迫在眉睫,为此,我们对青虾人工集约化高产养殖进行了一些探索。1鱼池条件养殖池位于五岳水库渔场,标准化鱼池6个,单池面积5亩,计30亩;形状为长方形,系东西走向;长宽比为2.5∶1;水源引自五岳水库,自流排灌,水质清新,溶氧丰富;进水口和排水口分设在虾池两端,设有过滤和防逃设备。2放养前的准备工作放养前15天,池塘经过干池暴晒和生石灰干法清塘(每亩施生石灰85kg),进水时用80目尼龙筛绢网过滤,加水1.0m左右。在鱼池中设置用旧网片、树枝和凤眼莲为青… 相似文献
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对2009年中国畜产品贸易总体和分品种情况做了简要分析,并且对2010年中国和世界畜产品贸易走势作出初步展望。预计2010年世界畜产品贸易将比2009年有所增加。 相似文献
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犬缺钙综合症是指各种原因引起的犬体内,主要是骨骼和血液中钙含量不足而造成的多种病症的总称,如佝偻病、骨软病、纤维性骨营养不良、产后子痫、低血钙症等.犬缺钙综合症是养犬过程中常见的一种疾病. 相似文献
8.
Qiang Li;Tao Liu;Hongda Li;Bin Wang;Hongtao Nie; 《Aquaculture Research》2024,2024(1):5552528
In order to produce gynogenetic diploid of Manila clam, Ruditapes philippinarum, we studied the optimal conditions of gynogenetic diploid induced by ultraviolet (UV). The irradiance of UV-induced sperm was 230 μW (cm2·s), and the irradiation time was 0, 3, 6, 9, 12, 15, 18, 21, 24, and 27 s. After the egg fertilized with genetically inactivated sperm, the fertilized eggs were treated with cytochalasin B (CB) at different concentrations of 0, 0.25, 0.50, 0.75, and 1.0 mg/L for 20 min. The ploidy of larvae under different induction concentrations were analyzed by flow cytometry, and the chromosome division process during sperm entry and cleavage was observed by fluorescence microscope. In addition, the ultrastructure of sperm, embryonic development, and chromosome were observed. The results showed that the fertilization rate and cleavage rate decreased gradually with the prolongation of UV irradiation time. We found UV irradiation for 9 s was the optimal time for haploid formation, with an induction rate of 100%. The CB treatment at 0.75 mg/L was the optimal concentration for the formation of D-larvae, and the induction rate was 9.60% ± 5.10%. The results showed that the optimal conditions for inducing gynogenetic diploid of R. philippinarum were irradiation with UV intensity of 230 μW (cm2·s) for 9 s and inhibited second polar body release by CB at concentration of 0.75 mg/L. In this study, the conditions for inducing Manila clam gynogenetic diploid were obtained, which lays the basis for further genetic research on the gynogenesis of R. philippinarum. 相似文献
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