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41.
BUNDIT YUANGSOI ORAPINT JINTASATAPORN NONTAWITH AREECHON PRATHAK TABTHIPWON 《Aquaculture Nutrition》2011,17(2):e306-e316
The optimal concentration of a panel of individual and combined carotenoid sources on skin pigmentation in fancy carp was investigated by nine experimental diets that were formulated and supplemented with astaxanthin at 25 mg kg?1, lutein at 25 and 50 mg kg?1, β‐carotene at 25, 50 and 75 mg kg?1, and lutein combined with β‐carotene at 25 : 25 and 50 : 50 mg kg?1, while a diet without supplemented carotenoid served as a control. The results showed that serum TC of fish fed diets containing supplemented with lutein plus β‐carotene at 25 : 25; 50 : 50 mg kg?1 and lutein 50 mg kg?1 diet were higher than the other treatments (P ≤ 0.05). Serum TC of the respective treatments was 6.2 ± 2.0, 7.8 ± 3.3 and 7.3 ± 1.9 μg mL?1 serum, respectively. Fish fed diets combined with lutein and β‐carotene at 25 : 25, 50 : 50 mg kg?1 and lutein 50 mg kg?1 diet had serum astaxanthin concentrations similar to fish fed the diet with astaxanthin alone at 25 mg kg?1. Serum astaxanthin concentrations was 0.7 ± 0.01, 0.9 ± 0.01, 0.4 ± 0.02 and 1.7 ± 0.18 μg mL?1 serum, respectively. The chromaticity of fish body skin of red and white position was assessed by colourimetry using the CIE L*a*b (CIELAB) system. Pigmentation response of skin redness of fancy carp fed with diets combined with lutein and β‐carotene at 25 : 25, 50 : 50 mg kg?1 and lutein 50 mg kg?1 were higher than other treatments (P ≤ 0.05) but they were similar to fish fed with 25 mg kg?1 astaxanthin diet. The redness (a* values) of fish fed diets with diets combined with lutein and β‐carotene at 25 : 25, 50 : 50 mg kg?1 and lutein 50 mg kg?1 were 28.3 ± 0.53, 29.9 ± 1.38, 28.8 ± 3.95 and 28.5 ± 2.49, respectively. After 3 weeks of feeding the experimental diets, the fish fed on a diet without carotenoid supplement for one week demonstrated that the same three groups still retained their redness and had an overall tendency to improve skin colouring. Finally, concentrations 50 mg kg?1 of lutein, or the combination of lutein and β‐carotene at 25 : 25 mg kg?1 showed the highest efficiency for improving skin pigmentation and redness of skin. 相似文献
42.
L. FENG H.‐H. HUANG Y. LIU J. JIANG W.‐D. JIANG K. HU S.‐H. LI X.‐Q. ZHOU 《Aquaculture Nutrition》2011,17(5):557-569
This study was to investigate the effect of dietary thiamin on the immune response and intestinal microflora in juvenile Jian carp (Cyprinus carpio var. Jian). Seven diets (0.25, 0.48, 0.79, 1.06, 1.37, 1.63 and 2.65 mg thiamin kg?1) were fed to Jian carp (8.20 ± 0.02 g). At the end of feeding trial, red blood cell counts and white blood cell counts increased with increasing dietary thiamin levels up to 0.79 and 1.06 mg kg?1 diet, respectively (P < 0.05); Lactobacillus counts in intestine increased gradually, and maximum values obtained when the thiamin level was at 0.79 mg kg?1 diet (P < 0.05). After the feeding trial, fish were injected with Aeromonas hydrophila only one time on the first day of the challenge trial and fed the same diets as the growth trial for 17 days. The survival rate, leucocyte phagocytic activity, lectin potency, acid phosphatase activity, lysozyme activity, total iron‐binding capacity and immunoglobulin M content of fish after being injected with A. hydrophila were all improved with increasing dietary thiamin levels up to a point, respectively (P < 0.05). These results suggested that thiamin could improve immune response and the balance of intestinal microflora of juvenile Jian carp. 相似文献
43.
《Veterinary anaesthesia and analgesia》2022,49(1):104-112
ObjectiveTo verify the efficacy of citral in inducing sedation and anesthesia in silver catfish (Rhamdia quelen) and grass carp (Ctenopharyngodon idella) and to assess the safety of essential oil (EO) of Aloysia citriodora and citral in inducing and maintaining anesthesia in silver catfish.Study designClinical study, randomized, parallel, multi-arm with control group in target species.AnimalsA total of 96 juvenile and 72 adult silver catfish and 80 juvenile grass carp were used.MethodsSilver catfish and grass carp were exposed to different concentrations of citral, 15–675 and 15–600 μL L–1, respectively, during the maximum period of 30 minutes to verify sedation and anesthesia induction and recovery times. In addition, for anesthetic induction, silver catfish were exposed to the EO of A. citriodora and citral at 225 μL L–1 for 3.5 minutes. Then, fish were transferred to an anesthesia maintenance solution at 50 μL L–1 for 10 minutes to assess hematologic and biochemical variables at 60 minutes, 2 and 6 days after treatment.ResultsCitral only induced sedation from 15, 25 and 40 μLL–1 in both species. Anesthesia without mortality was induced in silver catfish at 50–600 μL L–1 and grass carp at 75–450 μL L–1. At 675 and 600 μL L–1, mortality was recorded in silver catfish and grass carp, respectively. The EO of A. citriodora and citral were safe in inducing and maintaining anesthesia in silver catfish, with mean corpuscular hemoglobin concentration being the only variable that varied in relation to time and treatments.Conclusions and clinical relevanceCitral was effective in inducing sedation and anesthesia in both species. In addition, A. citriodora EO and citral were safe in inducing and maintaining anesthesia in silver catfish. Both agents are promising substances for the development of new drugs for fish. 相似文献
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为制备鲤春病毒血症病毒(SVCV)单克隆抗体(MAb),本研究用纯化的SVCV免疫BALB/c鼠,通过杂交瘤细胞技术,制备2株抗SVCV的MAb,分别命名为2A3和3H7。经间接ELISA检测腹水效价为1:10240和1:12150。亚类鉴定证实,这2株亚类均为IgG1型。经非竞争酶免疫试验测定2A3和3H7的抗体亲和力常数分别为4.86×108L/mol和1.86×109L/mol,3H7相对亲和力高于2A3。MAb 2A3和3H7的饱和度均为1:400,叠加试验所得增值指数为63.2%,大于50%。抗体反应增值结果表明:两株MAb分别针对不同抗原位点。免疫印迹分析检测表明,两株纯化的MAb均可与SVCV抗原发生特异反应。 相似文献
47.
为获得针对鲤春病毒血症病毒(SVCV)特异性的单克隆抗体(MAb),以纯化的SVCV为抗原,免疫BALB/c小鼠.将免疫鼠的脾细胞与SP2/0骨髓瘤细胞融合,采用间接ELISA法筛选获得4个能稳定分泌抗SVCV MAb的杂交瘤细胞株;4个杂交瘤细胞制备腹水的MAb效价为1:160 000~1:640 000.亚型鉴定结果表明,这些MAb分属2个亚型(1F1、3E1,IgG2a;3F5、4F9,IgGl),轻链均为K链.Western blot分析显示,MAb1F1、3F5、4F9能特异性地识别SVCV的N蛋白(47 ku),3E1能特异性地识别SVCV的G蛋白(69 ku).采用相加ELISA法对抗原表位分析结果显示,1F1、3F5、4F9可能识别相同的表位,3E1则识别不同的表位.间接免疫荧光试验结果显示4株MAb均能对染毒病灶产生特异性的荧光染色.这些MAb的制备为SVCV免疫学检测方法的建立奠定了基础. 相似文献
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草鱼羧肽酶A1基因(CPA1)部分片段的单核苷酸多态性(SNP)多态性及其与生长性状的关联分析 总被引:2,自引:0,他引:2
羧肽酶A (EC 3.4.16)是一类水解蛋白和多肽底物C端芳香族氨基酸或脂肪族氨基酸残基的消化酶.在草鱼生长相关的功能基因上研究单核苷酸多态性(SNP)与生长的相关性可为草鱼的分子辅助育种提供依据.本研究根据草鱼(Ctenopharyngodon idella)EST-SNP库的羧肽酶A1基因(CPA1)重叠群的2个Contig扩增该基因的序列片段,采用直接测序法,经过序列比对,共筛到2个颠换SNP位点:C+412A和A36C,分别位于CPA 1基因外显子5的34bp和内含子3的36 bp处,前者为错义突变.然后用一个群体的296尾草鱼对这2个位点用SnaPshot的方法进行检测和分型,统计基因型频率:A36C位点的AA基因型占26.7%,AC基因型占52.0%,CC基因型占21.3%.C+412A位点的AA基因型占15.5%,AC基因型占40.5%,CC基因型占43.9%.利用一般线性模型分析2个SNP位点与草鱼体质量、体长等重要生长性状的关系.关联分析结果显示,C+36A位点不同基因型在体质量、眼间距均值上存在显著差异(P<0.05).并且AA基因型和CC基因型在体质量、体长、体宽和眼间距上存在显著差异(P<0.05).AA基因型各项指标均值显著高于CC基因型.C+412A位点在体质量等生长性状上差异不显著(P>0.05),该位点和生长不相关,但是CC基因型和AC基因型在体重和肛前距上差异显著(P<0.05),该位点CC基因型的6个生长性状均值都高于AA基因型.由两个位点组成的5种双倍型在体质量上存在显著差异(P<0.05).双倍型D3和D5在体质量上存在差异显著(P<0.05).双倍型D3和D8在体质量、体宽、体长、体长/头长等生长性状上都存在显著差异(P<0.05).D3的各项指标均值最高,D8的各项指标均值最低.本研究结果显示,可以考虑将草鱼CPA1基因作为候选基因,用于草鱼的分子辅助育种. 相似文献
50.
Microsatellites have become the preferred molecular markers for strain selection and genetic breeding in fish. In this study
a total of 105 microsatellites were isolated and identified in gibel carp (Carassius auratus gibelio) by microsatellite sequence searches in GenBank and other databases and by screening and sequencing of positive clones from
the genomic library enriched for AG and GATA repeats. Moreover, nineteen microsatellites were randomly selected to design
locus-specific primer pairs, and these were successfully used to identify and discriminate different cultured strains of gibel
carp including strains A, D, L, and F. Three different types of microsatellite pattern were distinguished by the number and
length of fragments amplified from the 19 primer pairs, and some microsatellite primer pairs were found to produce different
microsatellite patterns among strains and strain-specific fragments. In addition, some duplicated alleles were also detected
in two microsatellite patterns. Therefore, the current study provides direct molecular markers to discriminate among different
cultured strains for selective breeding and aquaculture practice of gibel carp. 相似文献