• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.3
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• pp.384-391
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• 1996

This study was designed to investigate effects of lobster shrimp chitosan on serum and liver lipid levels in rats fed high fat and cholesterol diets. Male Sprague-Dawley rats of 4-weeks old, weighing 70$\pm$5g, were fed experimental diets for 3 weeks: basal diet+5% cellulose(group 1), high lipid diet+5% cellulose(group 2, control group), high lipid diet+5% balloon flower root(group 3), high lipid diet+5% cellulose(group 4, high lipid diet+5% lobster shrimp chitosan(group 5). Concentrations of total cholesterol, HDL-cholesterol, LDL-cholesterol, free cholesterol, cholesteryl ester, triglyceride, phospholipid in serum and liver were determined. The results obtained were as followes: Serum total cholesterol concentration were significantly reduced in all supplemented group compared with control. HDL-cholesterol concentrations were higher in groups 1, 4, and 5 and the ratios of HDL-cholesterol to total cholesterol concentration were higher in groups 1, 4, while the atherogenic-indices were lower in groups 1, and 4 than control. Concentrations of LDL, LDL-cholesterol and free cholesterol, cholesteryl ester were significantly lower in all supplemented groups than the control group. Concentrations of phospholipid and triglyceride were lower in groups 3, 4, 5, while activities of GPT and GOT were significantly lower in groups 4, 5 than the other group. Concentrations of calcium, magnesium and phosphorous were high in all treatment groups compared to the control group. Liver contents of total cholesterol, free cholesterol and cholesteryl ester were lower in the groups 1, 3, 4, and 5 than in the control group, especially lower in groups 1, and 5. Liver triglyceride and phospholipid concentrations were significantly lower in the groups 1, and 5 than in the other groups. The results from the data suggested that the experimental diet containing 5% lobster shrimp chitosan was effective to reduce the serum and liver lipids.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.7
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• pp.1025-1029
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• 2003

The effect studied was that of the feeding of shrimp by-product meal, as a source of eicosapentaenoic and docosahexaenoic acid, on growth performance and fatty acid composition of adipose tissue in growing pigs kept on small holdings in Central Vietnam. Shrimp by-product meal was exchanged with ruminant meal so that the diets contained either 0, 10 or 20% shrimp byproduct meal in the dry matter. The diets were fed on 6 different small-holder farms. The farmers fed a base diet according to their personal choice, but were instructed as to the use of shrimp by-product and ruminant meal. The diets were fed to the pigs from 70 to 126 days of age. There were three animals per treatment group per farm. The diets without and with 20% shrimp by-product meal on average contained 0.01 and 0.14 g docosahexaenoic acid/MJ of metabolisable energy (ME). Due to the higher contents of ash and crude fiber, the shrimp by-product meal containing diets had lower energy densities than the control diets. Eicosapentaenoic acid was not detectable in adipose tissue; the content of docosahexaenoic acid was generally increased after consumption of shrimp by-product meal. In spite of the concurrent high intakes of ash and crude fiber, the feeding of shrimp by-product meal had a general stimulatory effect on growth performance of the growing pigs. The intake of docosahexaenoic acid or its content in adipose tissue was not related with average daily gain. It is suggested that shrimp by-product meal may contain an unknown growth enhancing factor.

• Journal of Microbiology and Biotechnology
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• v.17 no.3
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• pp.511-515
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• 2007

White-spot syndrome virus (WSSV) is a devastating, infectious virus affecting shrimp. Although sensitive techniques involving PCR have been developed to assist farmers in screening shrimp (brood stock) for WSSV prior to stocking ponds, such practices have not yet been applied in Korea. Despite the rationality of implementing screening, there has been some doubt as to whether the stocking of WSSV-PCR-negative fly epidemiologically decreases white-spot disease outbreaks. Here, we report a retrospective analysis of data from shrimp farms in the western coast of Korea where WSSV-PCR-negative brood stocks were used to stock rearing ponds. A total of 366 shrimp from Heuksan Island were sampled for WSSV with PCR. Of the tested shrimp, 7.2% (28 brood stocks) were identified as WSSV positive; only WSSV-PCR-negative shrimp were used for brood stocks. Total unit production (final shrimp production/ the area of the ponds) was higher, at 1.96, in ponds where WSSV-PCR-negative shrimp were used, as compared with 1.02 in other ponds in Korea in 2004. This retrospective analysis of WSSV in Korea may be useful to the shrimp aquaculture industry, suggesting a testable hypothesis that may contribute to the eventual control of WSSV outbreaks.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.5
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• pp.624-633
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• 2021

This study was conducted to determine the supplemental effects of two insect meals, mealworm (MW) and black soldier fly (BSF), with high or low lipid levels in diets, on Pacific white shrimp Litopenaeus vannamei. Sardine and tuna by-product meals were used as the fish meal source in a control (Con) diet. The fish meals were replaced with MW, defatted MW (deMW), BSF or defatted BSF (deBSF), respectively. The shrimp (body weight: 0.47 g) were stocked into 20 acryl tanks (215 L) and fed the diets six times a day. After 45 days of the feeding trial, the shrimp that were fed insect meals had significantly higher phenoloxidase and superoxide dismutase activities than the shrimp fed Con diet. The gene expressions of prophenoloxidase, crustin and penaeidine-3c in shrimp hepatopancrease were also higher in shrimp that were fed the insect diets, regardless of defatting than those in shirmp that were fed Con diet. The survival against Vibrio parahaemolyticus was higher in shrimp that were fed the diets containing defatted insect meals than in shrimp that were fed Con diet. These results indicate that MW and BSF, regardless of lipid levels, could be good protein sources for the enhancement of innate immunity and anti-oxidant capacity of the shrimp.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.6
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• pp.909-917
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• 2020

This study was conducted to evaluate dietary supplementation of Sargassum horneri (SH) meal on growth performance, feed utilization, innate immunity, antioxidant capacity and disease resistance of Pacific white shrimp. The diets were added with graded levels of SH meal by 0, 0.5, 1, 2, 4 and 8% (designated as Con, SH0.5, SH1, SH2, SH4 and SH8, respectively). Quadruplicate groups of shrimp were hand-fed with one of the diets five times daily for 39 days. The innate immunity and antioxidant capacity of shrimp were significantly improved by the dietary SH supplementation. The cumulative survival of shrimp exposed to Vibrio parahaemolyticus in a challenge was higher in shrimp group fed SH diets, except for SH8, than that of shrimp fed the control diet. Growth performance and feed utilization of the shrimp were significantly decreased with the dietary SH inclusions except for 0.5%. Results indicated that dietary SH meal could be used as a functional supplement for improvements in innate immunity, antioxidant capacity and disease resistance in Pacific white shrimp. The suggested dietary inclusion level of dried SH is approximately 0.5% for the shrimp.

• Journal of Aquaculture
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• v.17 no.4
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• pp.282-288
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• 2004

This study was carried out to improve water thestability of extruded shrimp feed. Three types of extruded shrimp feeds which were control diet (no steaming, no wheat gluten), steaming treated diet and steaming treated diet containing wheat gluten were prepared to using the pilot scale extruder. Comparing with the water stability values of two types of extruded shrimp feed, Steamed shrimp feed containing 4% (w/w) wheat gluten showed on I after 48 h was better than the control diet (no steaming, no wheat gluten) of which water stability value was 4. Also Penaeus chinensis fed on the steamed feed showed good body weight gain (237%) and feed efficiency (16.7%) compared with body weight gain (151%) and feed efficiency (12.8%) of control diet in the feeding trial for 50 days. Briefly, the extruded shrimp feed has more efficient water stability on below I, and recommendable wheat gluten content and steaming time were 4∼8% (w/w) and 5∼10 minutes.

• Fisheries and Aquatic Sciences
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• v.23 no.1
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• pp.2.1-2.6
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• 2020

Background: As the cost of fishmeal continues to rise, there will be a need to optimize the diet by minimizing dietary fishmeal inclusion in aquafeed. In this study, a 7-week experiment was conducted to evaluate soybean meal, fermented soybean meal (soytide), and sesame meal as fishmeal replacers in whiteleg shrimp, Litopenaeus vannamei. Methods: A 30%-based fishmeal diet was considered as control (CON), six other diets were prepared by replacing 20% or 40% of fishmeal with soybean meal (SB₂₀ and SB₄₀), fermented soybean meal (ST₂₀ and ST₄₀), or sesame meal (SM₂₀ and SM₄₀) from the CON diet. Twenty shrimp with average initial weight of 0.65 ± 0.05 g (mean ± SD) were randomly distributed into 21 tanks (45 L) and fed four times a day. Water temperature was controlled at 28 ± 1 ℃ and aeration was provided by air stones. Results: Weight gain, specific growth rate, feed efficiency, and protein efficiency ratio of shrimp fed CON showed no significant differences compared to shrimp fed all the other diets. However, growth performance of shrimp fed ST₂₀ diet was significantly higher than those of shrimp fed the SM₂₀ and SM₄₀ diets (P < 0.05). Superoxide dismutase activity (SOD) of shrimp fed CON, ST₂₀, and ST₄₀ diets was significantly higher than those of shrimp fed the SB₄₀ and SM₄₀ diets. But there were no significant differences among shrimp fed CON, SB₂₀, ST₂₀, ST₄₀, and SM₂₀ diets. Also, lysozyme activity of shrimp fed ST₂₀ diet was significantly higher than those of shrimp fed the SB₄₀ and SM₄₀ diets. Although, lysozyme activity of shrimp fed the CON diet was not significantly different compared to shrimp fed all the other experimental diets. Conclusions: Therefore, SB, ST, and SM could replace 40% of fishmeal based on growth performance and lysozyme. According to the SOD activity, SB and SM could replace 20% of fishmeal and ST could replace 40% of fishmeal in juvenile whiteleg shrimp Litopenaeus vannamei.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.4
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• pp.273-281
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• 2008

In this study, the effect of slope length and angle at the entrance to fishing pots on the size of captured shrimp was examined to determine the optimal design of pots for use in Hokkaido, Japan. The purpose of the current study was to optimize the design of shrimp pots to allow greater control over the size of captured individuals for the purposes of shrimp resource management. Tank experiments were conducted to determine the optimal slope length and slope angle by analyzing the sizes of shrimp entering 10 model pots with combinations of five different slope lengths on slope angle of current shrimp pot, and five different angles on slope length of current shrimp pot. The results showed that, as the slope length of the pot increased, the size of individuals which entered the pot increased. In addition, as the slope angle was elevated in each of the five different slope angle treatments, the size of individuals entering was also increased.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.1
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• pp.8-14
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• 2017

A feeding trial was conducted to evaluate the effect of dietary supplementation with fermented soybean meal by Bacillus subtilis (BFSBM) on growth performance, feed utilization, innate immunity, water quality, and disease resistance of Litopenaeus vannamei. A basal fish meal-based diet was regarded as a control and two other diets were prepared by replacing 30% fish meal with either soybean meal (SBM) or BFSBM. Triplicate groups of shrimp ($0.80{\pm}0.010g$) were fed one of the experimental diets for 6 weeks. No differences were found in final body weight, feed conversion ratio, or survival among all dietary treatments after the feeding trial. Shrimp fed the BFSBM diet had significantly higher phagocytic and phenoloxidase activities than those of shrimp fed the SBM diet. Total ammonia concentrations in culture water during a zero water exchange test tended to decrease in tanks where BFSBM diet was provided. Disease resistance of shrimp to Vibrio harveyi tended to increase in the BFSBM group during 14 days of challenge compared to that in the control (CON) and SBM groups. These results show that dietary supplementation with BFSBM can enhance the innate immunity of Pacific white shrimp and replace at least 30% of dietary fish meal.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.57 no.4
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• pp.355-363
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• 2024

Although aquaculture shrimp production has increased, disease mortality has also increased. Acute hepatopancreatic necrosis disease (AHPND) is an emerging disease that significantly reduces production. In this study, we have investigated the potential of medicinal herbs in enhancing the immune system of shrimp. A mixture of medicinal herb extracts (Han In-jin, Artemisia iwayomogi kitamura and Cham Dang-gwi, Angelicae gigas Nakai) was absorbed into pellets and fed to whiteleg shrimp Litopenaeus vannamei for 12 weeks. The weight gain, immune activity, and disease resistance effects of the shirmp were examined. The growth performance of shrimp fed the mixture of medicinal herbal extracts was higher than that of the control group. The prophenoloxidase (proPO) activity was found to be significantly higher at 8 weeks in the 0.1% medicinal herb extract fed group. The cumulative mortality when artificially infected with AHPND pathogens commonly decreased in the 8 weeks fed group when compared with the control group. Furthermore, the RPS (relative percentage survival) was improved. This study confirmed that a mixture of medicinal herbal extracts has a positive effect on growth performance, innate immunity and disease resistance in shrimp. The optimum concentration of the medicinal herb extract for shrimp feed was 0.1% .