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Gale Researcher
Get PDFPresentation slidesOverview of Gale Researcher: a curriculum aligned library research collection based on the scope and sequence of introductory college courses, providing students with an easier way to find trusted, citable sources. Gale Researcher opens up new avenues to exploring and understanding the most studied topics by way of visually engaging pages filled with unique scholarly content, images, and videos
The search for Thomson’s “lost platform”, Ahu Rikiriki
Get PDFThe paper presents an analysis of historical records and archival materials about Ahu Rikiriki, first mentioned by
Thomson. The ahu was described as located on the southern cliffs of Rano Kau. In the 20th century, the site was
searched for without success at the vertical cliffs below the Karikari, in the vicinity of ‘Ōrongo, suggesting that
Ahu Rikiriki may have fallen into the sea in the late 19th or early 20th century. Other inaccessible places, such as
the cliffs of Pōike were also mentioned as a possible location of Ahu Rikiriki. This study aimed to find the place
at the Rano Kau caldera that would produce the best possible match with Thomson’s description of the ahu. The
entire southern rim of Rano Kau was studied, both from the cliff top and from the sea. In one particular place, in
the area formed by a large landslide, a patch of densely-packed stones was found in the middle of the cliffs, which
may possibly represent remains of fill of a destroyed ahu. In the shallow surf under the site, one can see numerous
ochre-colored boulders reminiscent of Rano Raraku tuff, standing out on the background of greyish stones that are
common to the place. The dimensions of these ochre-colored boulders are within the ranges expected for moai
Citrobacter freundii: a Causative Agent for Tail Rot Disease in Freshwater Cultured Japanese Eel Anguilla japonica
Get PDFTail rot disease causes significant economic damage in freshwater farmed Japanese eel Anguilla japonica, yet information on Citrobacter freundii as a possible causal agent for this disease is scarce. In this study, a virulent strain, temporarily named MINA, was isolated from diseased A. japonica suffering from tail rot disease. It was identified through phylogenetic analysis and phenotypic characteristics and thus compared to other known isolates. Isolate MINA has developed multiple resistances to penicillin, quinolones and sulfonamide antibiotics as well as to amide alcohols, cephalosporin, glycopeptide and macrolide drugs used in aquaculture when screened against a range of common antibiotics. To the best of our knowledge, this is the first report of tail rot disease caused by C. freundii in freshwater farmed A. japonica
Nutritional Evaluation of Rhizoclonium riparium var implexum Meal to Replace Soybean in the Diet of Nile Tilapia Fry
Get PDFA study was conducted to evaluate the potential of crinkle grass Rhizoclonium riparium var implexum meal (RM) as a substitute for soybean in the diet of sex-reversed Nile tilapia Oreochromis niloticus fry. Four experimental diets were prepared containing various inclusion rates of RM at 0% (Diet 1), 4.2% (Diet 2), 8.4% RM (Diet 3) and 12.6% (Diet 4) equivalent to 0%, 15%, 30% and 45% replacement of soybean meal, respectively. Results showed that Diet 4 resulted in significantly higher final average body weight (FABW), weight gain (WG), protein efficiency ratio (PER), and better feed conversion ratio (FCR) than Diet 1. Diets 2 and 3 resulted in statistically similar responses to those of both Diets 1 and 4. Specific growth rate (SGR) was not affected by the dietary treatments. Dietary proximate compositions were correlated with the performance indices. This study showed that Rhizoclonium riparium var. implexum meal could be included in the diet of Nile tilapia up to 12.6%, equivalent to 45% soybean meal replacement. This could be an important cost-effective measure for intensive culture of tilapia
Effects of Dietary Surfactin Supplementation on Growth, Digestive Enzyme Activity, and Antioxidant Potential in the Intestine of Growth Retarded Marbled Eel (Anguilla marmaorata) at Elver Stage
No full textA 70 day trial was conducted to investigate the effects of surfactin on growth, digestive enzyme activity, and antioxidant potential in the intestine of growth retarded marbled eels (Anguilla marmorata) at the elver stage. Six hundred and forty marbled eels at elver stage were randomly divided into four treatment groups with four replicates per group, and 40 fish per replicate. The dietary surfactin level of the four experimental diets was 0, 25, 50, and 100 mg/kg, respectively. Final body weight, weight gain rate, survival rate, protease activity in the intestine, malondialdehyde level, total antioxidation capacity level, and activities of superoxide dismutase, and glutathione peroxidase in the intestine of fish, increased significantly with surfactin supplementation, and feed conversion rates improved significantly (P0.05). Results demonstrated that dietary surfactin supplementation could improve growth performance, some digestive enzyme activities, and antioxidant potential, in the intestine of growth retarded marbled eel at elver stage. Surfactin could be used as a dietary growth promoter for growth retarded eels
Microsatellite-Based Analysis of Genetic Diversity and Relationship of Artificial Hybrid Jiyan-1 Puffer and their Parents, Takifugu flavidus and Takifugu rubripes
Get PDFIn this study, the genetic diversity and relationship of artificial hybrid Jiyan-1 puffer and their parents (T. flavidus ♀ and T. rubripes ♂) were evaluated using 15 microsatellite markers. The average number of alleles (Na), observed heterozygosity (Ho), and expected heterozygosity (He) of T. flavidus were higher than the average values of T. rubripes. Jiyan-1 puffer showed a relatively high level of genetic diversity, with an average allele number of 6.467 and mean observed and expected heterozygosity of 0.560 and 0.592, respectively. UPGMA cluster analysis indicated that Jiyan-1 puffer inherited more genetic information from female parents. This study indicates that the microsatellite markers will be useful for investigation of genetic background of puffer fish, as well as better conservation and sustainable utilization of puffer fish in aquaculture