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Algal Diets (algal + diet)
Selected AbstractsGROWTH OF CULTURED ABALONE, HALIOTIS FULGENS, USING NATURAL ALGAL DIETSJOURNAL OF PHYCOLOGY, Issue 2001Article first published online: 24 SEP 200 Pérez-Estrada, C. J.1,2, Serviere-Zaragoza, E.1, Mazariegos-Villareal, A.1, Reynoso-Granados, T.1 & Monsalvo-Spencer, P.1 1Centro de Investigaciones Biológicas del Noroeste (CIBNOR). P.O. Box 128, La Paz, Baja California Sur. 23000. México; 2Universidad Autónoma de Baja California Sur. Carretera al Sur km. 5.5 o 23080 o La Paz, B. C. S. Algal diets have been evaluated and used extensively for the aquaculture of abalone, especially in Japan. In other areas little is known about the nutritional value of the algae that the local abalone consume. In Mexico, regional hatcheries use Macrocystis pyrifera as a main source of natural food. Kelp availability, year round, has not generally been a problem for abalone aquaculturists. Most difficulties occur during severe storms, which may prevent access to kelp beds. El Niño also caused widespread destruction of M. pyrifera. In this study, growth rates of juvenile green abalone Haliotis fulgens, 31.7 " 1.5 mm shell length and 2.5 " 0.2 g body weight were evaluated during 136 days. Juveniles were fed with some of the algae used in regional hatcheries, Macrocystis pyrifera, Egregia menziesii, Eisenia arborea, Porphyra sp. and Ulva sp. Shell length growth rates varied between 2 mm day-1 for Ulva sp. and 18 mm day-1 for M. pyrifera. Body weight rates ranged from no growth for Ulva sp. to 14 mg day-1for E. menziesii. The percent of survival was between 46 and 75 %. Ulva sp. showed the lowest protein content followed by E. menziesii, E. arborea, M. pyrifera and Porphyra sp. [source] Algal diets for broodstock maintenance of the doughboy scallop Mimachlamys asperrima (Lamarck)AQUACULTURE RESEARCH, Issue 8-9 2000W A O'connor The effect of monospecific algal diets on filtration rate (algal cells h,1) and fecundity of Mimachlamys asperrima was investigated. Filtration rates of seven algal species were monitored to indicate species preferences and to estimate maximum daily filtration rates. Cells of Chaetoceros calcitrans and Pavlova lutheri were filtered most rapidly; however, on a cell weight (mg h,1) and cell volume (,L h,1) basis, scallops filtered more Rhodomonas salina and Tetraselmis chui from the water column. Filtration rates when fed the diatom Chaetoceros muelleri were the lowest of the tested species, with a relatively low weight and volume of the algae filtered. Maximum filtration rates of the tested species were estimated to vary between 2.25 × 109 and 7.68 × 109 cells scallop,1 day,1. Filtration of algal species by M. asperrima varied in accordance with both scallop size and water temperature. Five of the seven algal species previously tested were then selected for use as monoalgal diets for female M. asperrima and fed for 4 weeks. Fecundity of scallops after this treatment did not necessarily reflect filtration rates, being greatest for scallops fed C. muelleri, which was significantly greater than that of the scallops fed C. calcitrans. Percentage development of eggs to D-veliger larvae did not differ in accordance with the maternal diet. A combined diet of C. muelleri, P. lutheri and Tahitian Isochrysis aff. galbana averaging ,,2.5 × 109 cells scallop,1 day,1 was found to be suitable for the maintenance and conditioning of M. asperrima broodstock in recirculating systems. [source] Ontogenetic Shifts in the Ability of the Cladoceran, Moina macrocopa Straus and Ceriodaphnia cornuta Sars to Utilize Ciliated Protists as Food SourceINTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 3 2008Ram Kumar Abstract The ontogenetic diet shifts and age specific ability of the two cladoceran species Moina macrocopa and Ceriodaphnia cornuta to derive energy from ciliated protists have been investigated in laboratory. The postembryonic developmental rates and life table demography (longevity, age and size at first reproduction, fecundity and intrinsic rate of natural increase) of the cladocerans have been elucidated on algae (Chlorella vulgaris) and the ciliated protists (Tetrahymena pyriformis, Colpoda (c.f.) steini) as food. For either of the cladoceran, the somatic growth rate and average body size at first reproduction were higher with algal diet. During initial stages of development (0,5 days), either cladoceran realized higher rate of somatic growth on algal diet, subsequently ciliated protists supported significantly higher growth rate than the alga. Algal and ciliate diets did not differ in maximum body size (C. cornuta: 539,554 ,m; M. macrocopa: 1274.8,1309 ,m) reached by either of the cladocerans. The maximum body sizes were larger than size at first reproduction with either of the ciliated protists, however, with algal diet the maximum body sizes did not differ from the size at first reproduction in each case. In case of C. cornuta the generation time (20.5 ± 0.3 days on ciliate; 15.6 ± 0.17 days on algal diet), reproductive rates (net reproductive rate: 20.05 ± 3.2 on ciliate; 15.5 ± 1.2 on algal diet), and average life expectancy at hatching (27 ± 0.8 days on ciliate; 22.7 ± 0.71 days on alga) were higher, whereas the size at first reproduction (482 ,m on ciliate; 521 ,m on alga) was smaller with the ciliate than with an algal diet. The algal and the ciliate diets did not differ in survival (life expectancy at hatching: 9.2 ± 0.7 days) and fecundity (NRR: 23.6 ± 2.4) for M. macrocopa. The two ciliates used in the experiment did not differ in their performance as food source for either cladoceran species. Our results suggest that both the cladoceran species are able to utilize smaller ciliate (e.g., T. pyriformis, C. (c.f.) steini) as food; however with differential ability to derive energy from the ciliate diet and this ability is size and age structured in both cases. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Algal diets for broodstock maintenance of the doughboy scallop Mimachlamys asperrima (Lamarck)AQUACULTURE RESEARCH, Issue 8-9 2000W A O'connor The effect of monospecific algal diets on filtration rate (algal cells h,1) and fecundity of Mimachlamys asperrima was investigated. Filtration rates of seven algal species were monitored to indicate species preferences and to estimate maximum daily filtration rates. Cells of Chaetoceros calcitrans and Pavlova lutheri were filtered most rapidly; however, on a cell weight (mg h,1) and cell volume (,L h,1) basis, scallops filtered more Rhodomonas salina and Tetraselmis chui from the water column. Filtration rates when fed the diatom Chaetoceros muelleri were the lowest of the tested species, with a relatively low weight and volume of the algae filtered. Maximum filtration rates of the tested species were estimated to vary between 2.25 × 109 and 7.68 × 109 cells scallop,1 day,1. Filtration of algal species by M. asperrima varied in accordance with both scallop size and water temperature. Five of the seven algal species previously tested were then selected for use as monoalgal diets for female M. asperrima and fed for 4 weeks. Fecundity of scallops after this treatment did not necessarily reflect filtration rates, being greatest for scallops fed C. muelleri, which was significantly greater than that of the scallops fed C. calcitrans. Percentage development of eggs to D-veliger larvae did not differ in accordance with the maternal diet. A combined diet of C. muelleri, P. lutheri and Tahitian Isochrysis aff. galbana averaging ,,2.5 × 109 cells scallop,1 day,1 was found to be suitable for the maintenance and conditioning of M. asperrima broodstock in recirculating systems. [source] | ||||||||||