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931.
Parentage analysis of tropical spiny lobster (Panulirus homarus) by microsatellite markers 下载免费PDF全文
Madjid Delghandi Manal Saif Nasser Al Hinai Hasifa Afzal Mohamed Khalfan Al‐Wahaibi 《Aquaculture Research》2017,48(9):4718-4724
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
932.
Effects of different carotenoid supplementation sources with or without sodium taurocholate on growth,feed utilization,carotenoid content and antioxidant status in fry of the European seabass,Dicentrarchus labrax 下载免费PDF全文
Ahmed Elsayed Sallam Abdallah Tageldien Mansour Tarek Mohamed Srour Ashraf Mohamed Abdelsameè Goda 《Aquaculture Research》2017,48(7):3848-3858
A total of 210 European seabass fry with an average body weight of 0.51 ± 0.03 g were divided into seven experimental treatments (three replicates per treatment). The seven experimental diets (45.64% CP) were formulated to contain synthetic astaxanthin (SA; 0.1 g kg?1), marigold flower meal (MFM; 0.2 g kg?1) or crab waste meal (CM; 10 g kg?1), with or without sodium taurocholate (ST; 0.4 g kg?1); the control diet contained no supplementation. The experiment was conducted for 8 weeks. The results show that seabass fry fed the diets containing different sources of carotenoids, especially with ST, demonstrated higher growth efficiency, survival (%), feed efficiency, protein and ether extract contents of fish body. The best results were found with DietMFM+ST. Whole‐body carotenoid levels increased significantly with all supplementation treatments; the highest level was observed with SA, followed by fish fed DietMFM and DietCM, especially with ST co‐supplementation. Moreover, thiobarbituric acid‐reactive substances were significantly reduced in fish fed the diets containing different sources of carotenoids compared to the control diet. The total antioxidant status significantly increased in fish fed DietSA and DietCM alone or with ST compared to the control group. In conclusion, these results reveal that DietMFM+ST is the most suitable treatment for improving growth, feed efficiency, and the protein and ether extract contents of seabass fry compared to other sources of carotenoids. The best oxidant/antioxidant balance and carotenoid content were achieved using SA, CM and MFM with ST supplementation. 相似文献
933.
The status of marine biodiversity in the Eastern Central Atlantic (West and Central Africa) 下载免费PDF全文
Beth A. Polidoro Gina M. Ralph Kyle Strongin Michael Harvey Kent E. Carpenter Rachel Arnold Jack R. Buchanan Khairdine Mohamed Abdallahi Camara Bruce B. Collette Mia T. Comeros‐Raynal Godefroy De Bruyne Ofer Gon Antony S. Harold Heather Harwell Percival A. Hulley Tomio Iwamoto Steen W. Knudsen Jean de Dieu Lewembe Christi Linardich Kenyon C. Lindeman Vanda Monteiro Thomas Munroe Francis K.E. Nunoo Caroline M. Pollock Stuart Poss Barry Russell Catherine Sayer Aboubacar Sidibe William Smith‐Vaniz Emilie Stump Mor Sylla Luis Tito De Morais Jean‐Christophe Vié Akanbi Williams 《水产资源保护:海洋与淡水生态系统》2017,27(5):1021-1034
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934.
Mohamed Salah Azaza Wassim Kammoun Abdelwaheb Abdelmouleh Mohamed Mejdeddine Kraϊem 《Aquaculture International》2009,17(6):507-521
This study was undertaken in order to determine the effect of feeding heat-treated, defatted soybean meal (SBM) on growth,
feed utilization, and body composition of Nile tilapia (Oreochromis niloticus). A control diet (SBM0) of 378 g kg−1 crude protein with 18.4 kJ g−1 gross energy was formulated, and three diets identical to the basal diet were autoclaved for 10, 20, or 30 min. The autoclaved
diets were named SBM10, SBM20, and SBM30, respectively. Each diet treatment was applied to triplicate groups of 30 fish (2.45 ± 0.03 g) per tank (120 l). The fish
were hand fed to satiation four times daily for 45 days. At the end of the feeding trial the fish fed with the SBM30 diet had significantly (P < 0.05) higher weight gain and protein efficiency ratio than those fed with the other diets. No feed-related mortality was
observed during the whole experimental period. Heating SBM for 30 min reduced trypsin inhibitor activity (TIA) and increased
apparent protein digestibility (APD), and indicated significant differences (P < 0.05) among various treatments. No significant differences were found in carcass moisture, lipid, and ash of fish fed with
different experimental diets. An increase in the body protein content of fish fed with diet SBM30 was significantly (P < 0.05) higher than in all other experimental groups. The results of this study seem to indicate that autoclaving the SBM
for 30 min improved its nutritional value in practical feeds for Nile tilapia fingerlings. 相似文献
935.
Mohamed A Sweilum Mohamed M Abdella & Shady A Salah El-Din 《Aquaculture Research》2005,36(14):1414-1421
The effects of dietary protein‐energy levels on the growth rate, proximate composition and production were examined in Nile tilapia, Oreochromis niloticus, at two starting weights (22.9 and 39.8 g) reared in concrete ponds for 180 days. The highest weight gain (183.1 g) was obtained with fish fed a 30% protein and 10.5 kJ g?1 diet for the small initial size and 180.2 g for a diet containing 25% protein and 12.6 kJ g?1 for the large initial size. Dressed yields (edible mass) and fillets increased to 56.9% and 52.5% in fish fed diet with 25% protein and 10.5 kJ g?1 at the initial size of 22.9 g, while fish started at 39.8 g exhibited the best values (56.5% and 52.1%) when fed the 30% protein and 10.5 kJ g?1 diet. Proximate composition of soft tissue (wet weight basis) in small fish was significantly influenced by dietary protein‐energy levels. Protein was 26.1±0.3% in fish fed the high protein (30%) and low energy (10.5 kJ g?1 diet), while lipid content was 6.4±0.3% at diet containing 20% protein and 14.7 kJ g?1 diet. Large initial size fish fed the diet with 25% protein and 14.7 kJ g?1 had the highest body protein (32.0±0.4%) and lowest lipid content (2.2±0.3%). Feed conversion ratio (FCR) and protein efficiency ratio varied with different dietary protein‐energy levels and initial fish sizes. Feed conversion ratio increased with increasing protein and decreasing energy level in the diet, and values in small fish were higher than values in large fish. Protein efficiency ratio decreased with increasing dietary protein level and decreasing energy level. The maximum total production (7.6 tons feddan?1) was with dietary high protein (30%) and low energy (10.5 kJ g?1) for small‐sized fish, while large initial fish had the highest production (3.7 tons feddan?1) when fed the 25% protein and 12.6 kJ g?1 diet energy. Starting with 22.9 g fish was more advantageous than the initial size of 39.8 g for rearing Nile tilapia. Small fish required a high‐protein and low‐energy diet, whereas large fish required a low‐protein and high‐energy diet to achieve highest production. 相似文献
936.
Mohamed Ayaz Hasan Chisty Roshada Hashim & Alexander Shu -Chien Chong 《Aquaculture Research》2009,40(5):519-525
Biochemical assays and substrate SDS-PAGE were conducted to partially characterize and identify various types of proteases present in the digestive tract of PL15 giant freshwater prawn ( Macrobrachium rosenbergii ). Casein hydrolytic assay of the enzyme extracts showed major proteolytic activities at pH 3.0, 6.0 and 9.0, while assay of preincubated enzyme extracts with phenylmethylsulphonyl fluoride (PMSF), a serine protease inhibitor produced a 33.17% reduction in alkaline protease activity. When specific inhibitors tosyl-lysine chloromethyl ketone and tosyl-phenylalanine chloromethyl ketone were used, they resulted in a reduction in activity of proteases in the enzyme extracts by 82.41% and 55.03%, respectively, confirming the presence of trypsin and chymotrypsin, while ethylenediamine tetraacetic acid produced protease activity reduction in 33.92% showing the presence of metalloproteases in the digestive tract of the prawn. Further characterization of the alkaline proteases using SDS-PAGE technique, after incubating the extract in the presence or absence of specific inhibitors, produced six bands corresponding to molecular masses of between 13.48 and 136.1 kDa; two trypsin bands of 13.48 and 36.4 kDa, three chymotrypsin bands in the range of 23.0–73.4 kDa and one for metalloprotease of 136.1 kDa, all of which were identified from a zymogram. This study suggests that protein digestion in M. rosenbergii is initiated by an acid protease followed by a combination of action of alkaline proteases: trypsin, chymotrypsin and metalloproteases. 相似文献
937.
Salem Mohamed Omar Abdalla Salem Tarek A. Yürüten Özdemir Keriman Sönmez Adem Yavuz Bilen Soner Güney Kerim 《Fish physiology and biochemistry》2021,47(4):1053-1062
Fish Physiology and Biochemistry - In the present study, antioxidant activity, immune responses, and growth performance of rainbow trout (Onchorhynchus mykiss) juveniles fed with diets supplemented... 相似文献
938.
A growth study was conducted to determine the dietary niacin requirement of the Indian catfish, Heteropneustes fossilis (Bloch), fingerlings (Mean weight 9.41 ± 0.18 g). Semi‐purified diets with five levels (0, 5, 10, 20 and 40 mg kg?1 diet) of supplemental niacin were fed to H. fossilis for 15 weeks. Each diet was fed to three replicate groups of fish. Results indicated that the highest (P < 0.05) weight gain was for the fish fed the diet supplemented with 20 mg niacin kg?1, followed by fish fed the diets with 40, 10 and 5 mg niacin kg?1, and the lowest in fish fed the unsupplemented control diet. Patterns of specific growth rate (SGR) and protein efficiency ratio (PER) were similar to those of the weight gain. Survival of fish fed the control diet and niacin‐supplemented diet was 58% and 91–100% respectively. Niacin deficiency signs such as anaemia, anorexia, lethargy and skin haemorrhage were observed in fish fed the control diet. The haematocrit values (Ht) were higher (P < 0.05) in fish fed the diets supplemented with niacin than in fish fed the control diet. The hepatosomatic indexes (HSI) of fish fed with or without niacin‐supplemented diets were not significantly (P > 0.05) different from each other. Both body protein and lipid content were higher (P < 0.05) in fish fed the diet supplemented with 20 and 40 mg niacin kg?1, respectively, than those fish fed other diets. The niacin content in liver significantly (P < 0.05) reflected the supplementation level in the diet and ranged from 29.11 to 40.31 mg g?1 tissue. The associated liver niacin content for growth was about 47 μg g?1 tissue. Quadratic regression analysis showed that the dietary niacin requirement for maximal growth of H. fossilis under these experimental conditions was about 25 mg kg?1 diet. 相似文献
939.
Effect of probiotics on the survival, growth and challenge infection in Tilapia nilotica (Oreochromis niloticus) 总被引:1,自引:0,他引:1
This study was conducted in order to evaluate the potential benefit of Bacillus pumilus and a commercial product (‘Organic Green'?) as a probiotic in the culture of the tilapia nilotica. Two doses of B. pumilus (106 and 1012 g?1 diet fed) and Organic Green? (1 and 2 g kg?1 diet fed) were used as feed additives and administered for periods of 1 (groups 2, 3, 4 and 5 respectively) and 2 (groups 6, 7, 8 and 9 respectively) months; group 1 served as a control. Each group consisted of 4 equal replicates of 320 fish. Body weight, nitroblue tetrazolium (NBT) activity, haematocrit values and total and differential leucocytic counts (TLC and DLC) were recorded in each group after 1 and 2 months. At the end of the experiment (8 months), survival and individual body weights were recorded. Challenge infections were performed after 1, 2 and 8 months using 0.5 mL culture suspension of a pathogenic reference strain of Aeromonas hydrophila (108 bacteria mL?1). The NBT values were increased significantly in all treated groups, except those administered B. pumillus (groups 3 and 6). There were significant changes in haematocrit values and TLC and DLCs in the treated groups, except group 3, which showed a significant increase in TLC, lymphocytes and monocytes. There was a statistically significant increase in the individual body weight in groups 5, 6, 8 and 9. The survival rates of all treatment groups were higher than the control group, the differences being statistically significant in groups 3 and 9. The challenge infection showed a variable response with the type and dose of treatment and the period of application. The highest relative levels of protection were an average increase of 62.5% after 1 month (groups 3 and 5), 55.6% after 2 months (group 7) and 15.8% after 8 months (groups 8 and 9). Overall, both types of probiotics induced a similar effect. The results show the potential of using probiotics to enhance immune and health status and improve disease resistance in Oreochromis niloticus, thereby improving growth performance. However, further extensive testing, including a full commercial cost–benefit analysis, is necessary before recommending their application in aquaculture. 相似文献
940.
The cyclopoid copepod Apocyclops dengizicus was isolated from a marine shrimp pond, Penaeus monodon, Kuala Selangor, Malaysia, and reared in the laboratory for 3 months to establish a pure population stock. Amino acids and fatty acids of A. dengizicus were determined when fed Chaetocerous calcitrans (C), Tetraselmis tetrathele (T) and their combination (CT) (1:1 by number). The protein contents in A. dengizicus that received C, T and CT were 46.8%, 60.5% and 55.3% of dry weight respectively. Correspondingly, the lipid was 19.0%, 17.8% and 19.1% of dry weight for C, T and CT respectively. The A. dengizicus cultured on C, T and CT had total essential amino acids without tryptophan measurement of 57.1, 60.3 and 67.8 and total non‐essential amino acids of 42.9%, 40.0% and 32.2% of total amino acids. The fatty acid content of A. dengizicus showed that it was able to synthesize docosahexenoic acid (22:6n‐3, DHA), eicosapentaenoic acid (20:5n‐3, EPA) and arachidonic acid (20: 4n‐6, ARA) from examined microalgal diets. The DHA:EPA:ARA ratios of A. dengizicus fed on C, T and CT were 6.8:3.0:1, 14.0:5.8:1 and 11.6:2.6:1 respectively. Apocyclops dengizicus could be suitable live food for larval fish and shrimp rearing because it meets their nutritive requirements. 相似文献