Three species of Solieriaceae (Rhodophyta), Betaphycus gelatinus, Eucheuma serra and Meristotheca papulosa are economically important species, that are found in subtropical to tropical waters and are well represented in the coastal area of Ryukyu and Kyushu Islands of Japan. This study was motivated by the need to establish basic information regarding their physiology, in order to design a cultivation system. Two experiments were conducted to determine how five temperature treatments of 16, 20, 24, 28 and 32℃ influenced growth and photosynthesis, as determined by a dissolved oxygen sensor. An additional experiment examined how nine irradiance levels of 0, 13, 26, 48, 68, 168, 248, 342 and 536μmol photon m-2 s-1 at 24℃ influenced photosynthetic rates. Optimal relative growth rates of B. gelatinus and E. serra under 90μmol photon m-2 s-1 occurred from 24℃ and 28℃, while for M. papulosa it ranged from 20℃ and 24℃. Maximum photosynthetic rates (Pmax) for B. gelatinus, E. serra and M. papulosa were 135.0, 65.0 and 52.4μg O2 (mg chl-a)-1 min-1 , respectively and saturated beyond 94.9, 69.4 and 35.4μmol photon m-2 s-1 , respectively. These characteristic results were closely related to their depth of the habitat and local distribution in southern Japan, and provide information required to design their mass-cultivation systems.
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The cultivation of seaweeds contributes significantly to the national economy and provides employment to the economically backward communities of Sabah, Malaysia. Cultivation of seaweeds on a commercial scale requires a large number of propagules with desirable phenotypic traits which include high growth rates and resistance to diseases. Thus, seaweed tissue culture can be considered as one of the best methods to provide a large amount of seedlings for commercial cultivation. The parameters which have been determined to have a significant effect on the growth of in vitro propagated Eucheuma seaweeds are the sterilization techniques, media composition, light intensity and aeration. Eucheuma seaweeds were surface sterilized by washing with optimized concentration of disinfectants and antibiotics. The appropriate medium was determined to be Provasoli’s Enriched Seawater (PES) while optimum light intensity was in the range of 6,000 lux. Continuous aeration was important to provide enough carbon dioxide for carbon fixation. Hormone IAA:BAP was provided with concentration ratio of 5:1 mg/l. Temperature was maintained in the range of 25 to 30°C while salinity of the seawater was kept constant at 32 ppt.
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The impact of gravity of renal failure for the current study on human health is well known and as there is no specific pharmacotherapy for renal failure, undertaken to evaluate the effect of seaweed extract of Chlorococcumhumicola, belongs to chlorophyta and is a unicellular green algae. The algae were collected from Mandabam, Rameshwaram, Tamil Nadu, India. Marine algae have been the source of active compounds where, they are used for various applications. The medicinaluse in traditional medicine has been reported since time immemorial. The present study is on the marine algae Chlorococcumhumicolawas investigated. The ethanol, ethyl acetate and hexane extracts of Chlorococcumhumicola were analyzed and subjected to phytochemical to know the secondary metabolites present in the ethanol extracts and showed the better activity so it was subjected for in vitro Nephroprotective activity.
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Chondracanthus chamissoiis a red algawhich is acquiring an increasing economic impor-tance in Chile and becoming a target species forcultivation. Because epiphytism is a major problem inthe mariculture of seaweeds, the recruitment ofUlvasp. andEnteromorphasp. on gametophytic (cysto-carpic) and tetrasporophytic thalli ofC. chamissoiwas testedin vitroon four populations from differentlocations in Chile. ForUlvasp., the density, cover andlength of the recruits varied between the reproductivephases of the host and among the studied populationsofC. chamissoi. In most experiments, a larger numberof epiphytic thalli was observed on gametophyticplants ofC. chamissoi; populations from Calderillaand Lechagua had a higher resistance to epiphytism.ForEnteromorphasp., its ability to grow epiphyti-cally on both phases of the host showed a greatervariability, but was inferior to that ofUlvasp. Thedifferential resistance to epiphytism in both reproduc-tive phases and in plant origin indicates the possibilityof obtaining selected strains ofC. chamissoiwithlower susceptibility to epiphytism that could beutilized in planning maricultural programs.
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Gracilaria species were subjected to different salinities under laboratory conditions and changes in the photosynthetic oxygen evolution and fluorescence kinetics were followed. The plants which were subjected to more or less the normal salinity conditions exhibited low values of variable fluorescence and quantum yield. Prolonged treatment increased the quantum yield but the pigment content and the photosynthetic rate reduced significantly Among the two species tested, Gracilaria edulis was found to be very sensitive to low salinity (15 ppt) and G. crassa to higher salinity (45 ppt).
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Obtaining eggs and larvae in large quantities is a critical point for the economic viability of sea cucumber aquaculture. In this paper, spawning induction methods and in-vitro fertilisation (IVF) methods are presented and compared. The IVF technique developed in Madagascar (MH-IVF) is a simple, cost-efficient method that enables hatcheries to obtain clean, fertilised eggs of sea cucumbers year-round. MH-IVF does not require high-tech equipment and is applicable in small- and large-scale hatcheries. It ensures the best control at the very beginning of the work on the number and type of genitors (i.e. sex, length, weight, colour); the quality of the gonads (healthy versus parasitised); and the number, size and quality of spermatozoa and eggs. MH-IVF involves the sacrifice of very few genitors compared with the individuals obtained and sacrificed for production. Yet, it does not influence genetic drift any more than spawning induction methods.
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Livestock production, particularly enteric methane production, contributes to greenhouse gas emissions globally. Various mitigation strategies developed to reduce enteric emissions have limited success. Although in vitro studies have shown a considerable reduction in methane emissions using Asparagopsis spp., no studies have been conducted to investigate the effect of any species of Asparagopsis in dairy cattle. Our objective was to evaluate quantitatively the response of cows consuming Asparagopsis armata on methane production (g/kg), yield (g/kg feed intake) and intensity (g/kg milk yield). Twelve post-peak lactating Holstein cows were randomly assigned to three treatments (control, 0.5% and 1% inclusion levels of A. armata on organic matter basis) in a 3 × 3 Latin square design with three 21-day periods. Enteric methane emissions were measured using the GreenFeed system. Methane production by cows decreased significantly by 26.4% at the low (0.5%) level of A. armata inclusion and 67.2% at the high (1%) level of inclusion. Feed intake was reduced by 10.8 and 38.0%, in cows fed the low and high level of macroalgae inclusion, respectively. Methane yield decreased significantly by 20.3 and 42.7% in cows fed diet including 0.5% and 1% A. armata inclusion levels, respectively (P = <0.0001). Methane intensity significantly decreased by 26.8% from cows fed at 0.5% level and 60% at the 1.0% A. armata inclusion level. Bromoform concentrations in milk were not significantly different between treatments. Our in vivo results showed that A. armata has potential to be used as a feed additive to reduce enteric methane emissions.
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Comminuted meat products represent a diverse class of meat products that are popular for their characteristic texture and flavor. Comminuted meat products are incorporated with dietary fibers for various functional and nutritional purposes. These fibers are mostly the carbohydrate polymers of different types. The dietary fibers have been observed to affect the texture of meat products irrespective of the reason for their incorporation. These fibers have been shown to enhance the functional properties and health benefits of meat products. The effect of different fibers on the textural and other quality attributes has not been reported uniformly by the researchers making it hard to compare these studies. In this review, we have given an overview of the textural properties of comminuted meat products and summarized the existing researches reported on the textural changes of meat products due to soluble dietary fiber incorporation.
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This presentation covers
- What seaweeds are
- The history of seaweed cultivation
- The use of seaweed in food, merchandise, medicine, biofuel, fertilizers, animal feed, and etc.
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Factors determining the degree of dietary generalism versus specialism are central in ecology. Species that are generalists at the population level may in fact be composed of specialized individuals. The optimal diet theory assumes that individuals choose diets that maximize fitness, and individual specialization may occur if individuals' ability to locate, recognize, and handle different food types differ. We investigate if individuals of the marine herbivorous slug Elysia viridis, which co-occur at different densities on several green macroalgal species in the field, are specialized to different algal hosts. Individual slugs were collected from three original algal host species (Cladophora sericea, Cladophora rupestris and Codium fragile) in the field, and short-term habitat choice and consumption, as well as long-term growth (proxy for fitness), on four algal diet species (the original algal host species and Chaetomorpha melagonium) were studied in laboratory experiments. Nutritional (protein, nitrogen, and carbon content) and morphological (dry weight, and cell/utricle volume) algal traits were also measured to investigate if they correlated with the growth value of the different algal diets. E. viridis individuals tended to choose and consume algal species that were similar to their original algal host. Long-term growth of E. viridis, however, was mostly independent of original algal host, as all individuals reached a larger size on the non-host C. melagonium. E. viridis growth was positively correlated to algal cell/utricle volume but not to any of the other measured algal traits. Because E. viridis feeds by piercing individual algal cells, the results indicate that slugs may receive more cytoplasm, and thus more energy per unit time, on algal species with large cells/utricles. We conclude that E. viridis individuals are specialized on different hosts, but host choice in natural E. viridis populations is not determined by the energetic value of seaweed diets as predicted by the ODT.
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