• Journal of Microbiology and Biotechnology
• /
• 제28권6호
• /
• pp.946-956
• /
• 2018

The gut microbiota of aquatic animals plays a crucial role in host health through nutrient acquisition and outcompetition of pathogens. In this study, on the basis of the high-throughput sequencing of 16S rRNA gene amplicons, we examined the bacterial communities in the gut of freshwater shrimp (Macrobrachium nipponense) and in their living environments (sediment and pond water) and analyzed the effects of abiotic and biotic factors on the shrimp gut bacterial communities. High bacterial heterogeneity was observed in the freshwater shrimp gut samples, and the result indicated that both the surrounding bacterial community and water quality factors (particularly dissolved oxygen and temperature) could affect the shrimp gut bacterial community. Despite the observed heterogeneity, 57 genera, constituting 38-99% of the total genera in each of the 40 shrimp gut samples, were identified as the main bacterial population in the gut of M. nipponense. In addition, a high diversity and abundance of lactic acid bacteria (26 genera), which could play significant roles in the digestion process in shrimp, were observed in the shrimp gut samples. Overall, this study provides insights into the gut bacterial communities of freshwater shrimp and basic information for shrimp farming regarding the application of probiotics and disease prevention.

• 생명과학회지
• /
• 제8권5호
• /
• pp.550-556
• /
• 1998

염소, 요오드, 담수처리에 의한 바이러스 병원성 약화 시험결과, 염소 5 ppm이상에서, 담수 50% 이상에서 살균효과를 나타내었으나 요오드는 효과가 없었다. Peptidoglycan, schzophyllan의 면역증강 효과를 시험한 결과, 각각 7일간 격 투여구와 2일간격 투여구에서 생존율이 대조군에 비해 높게 나타났다. 화학적, 효소적, 생물활균제를 투여하여 수질 및 저질 개선시험결과 화학적 개선제, Mg(OH)$_2$의 효과가 수질, pH, 강열감량 부분에서 효과가 가장 컸으며, 특이하게 효소적 개선제는 총 황화물의 농도를 약간 높이는 것으로 나타났다.

• 한국양식학회지
• /
• 제20권4호
• /
• pp.278-288
• /
• 2007

새우양식은 90년대 서해안을 중심으로 빠르게 발달하여 2001년에는 2,605ha의 면적에서 3,268톤이 생산되었으나 2004년에는 2,368톤으로 해마다 감소되고 있다. 이러한 원인 중의 하나는 흰반점바이러스(WSSV)에 의한 대량폐사에 기인하는 것으로 알려져 있다. 흰반점바이러스는 현재 세계적으로 새우양식산업에 심각한 피해를 입히는 바이러스로 우리나라에는 1993년 처음 보고된 후 해마다 새우양식장에 반복적인 대량폐사를 유발시킨다. 축제식 새우양식장의 질병 피해를 감소시키기 위한 방법의 하나로서 새우와 어류, 패류, 해조류를 함께 복합양식하는 방법이 많은 연구되어 있으며 또한 육식성 어류와의 복합양식은 질병새우를 선택적으로 포식함으로써 새우의 바이러스 발병을 지연 혹은 억제시키는 것으로 알려져 있다. 새우양식장에 육식성 어류인 황복 Takifugu obscurus을 복합적으로 사육함으로써 바이러스 억제 효과를 조사하기 위하여 수면적 $1,616{\sim}1,848\;m^2$의 4개 축제식 양식장에 각각 흰다리새우($46.9/m^2$), 흰다리새우($43.4/m^2$)+황복($0.22/m^2$), 대하($24.6/m^2$), 대하($30.3/m^2$)+황복($0.25/m^2$)의 밀도로 입식하고 95일간 사육하였다. 대하 단독구와 복합구는 각각 51일, 57일째 WSSV 발병으로 전량 폐사하였다. 흰다리새우 단독구의 생존율은 18.2%인 반면 복합구의 생존율은 32.4%이며 단위생산량은 단독구에 비해 69.2%가 높아 흰다리새우는 황복과 복합양식이 단독양식에 비해 훨씬 유리한 것으로 나타났다. 사육수의 영양염(TAN, $NO_2-N,\;NO_3-N$) 농도는 복합구가 단독구에 비해 2배 이상 높았으나 전체적으로 새우의 성장에 적정범위를 유지하였다. 대하는 흰다리새우에 비해 WSSV에 대한 감수성이 높은 것으로 나타났으며 따라서 대하와의 복합양식은 이러한 점이 충분히 고려되어야 할 것이다.

• Ocean and Polar Research
• /
• 제35권4호
• /
• pp.323-349
• /
• 2013

The mud shrimp Upogebia major (Upogebiidae: Decapoda: Crustacea) is a common species on muddy and sandy mud tidal flats in the west coast of Korea. They reside in Y-shaped burrows that can extend up to more than 2 meters below the sediment surface. They feed on suspended detritus carried into their burrow by the beating of their pleopods and captured by their hairy first two pairs of thoracic legs. Mud shrimp burrows provide a habitat for a variety of small organisms such as crabs, shrimps, polychaetes, and mollusks. Ovigerous females are observed from December to May. Females deposit eggs only once per breeding season. They start hatching in March and the pelagic larvae of first zoea appear in March and April, followed by benthic settlement in May. Growth over the first year is rapid, and females deposit their first eggs in the third breeding season, 31 months after their settlement. Adult shrimps live for 4~5 years. Depth of the burrow increases with body length. The deep burrows provide refuge from predators and physical stress, allowing the shrimps to survive for a long time. The mud shrimps supply oxygen-rich water to their deep burrows, and exert a great influence on the structure and metabolism of the tidal flat benthic community. However, recently this type of mud shrimp has posed a serious threat to the Korean clam industry along the west coast of Korea. The extensive burrowing shrimp populations suddenly invaded the tidal flats from 2010 where the clams (Ruditapes philippinarum) are raised. As a consequence, clam production has decreased by about 10% over the past three years in some Korean clam beds. Therefore, the objective of this study is to review the biology of this mud shrimp in order to seek solutions to control the burrowing of these shrimps.

• 동아시아식생활학회지
• /
• 제19권5호
• /
• pp.743-749
• /
• 2009

This study was conducted to investigate the quality characteristics of tofu prepared with the addition of shrimp powder. Moisture, crude ash, carbohydrate, crude protein, crude lipid of the used shrimp powder were 3.81%, 0.70%, 42.15%, 49.36%, and 3.98%, respectivly. The yield rate of the tofu did not differ significantly according to the level of added of shrimp powder, however there was a significant decrease in pH and a significant increase in acidity. The L and b values of the tofu were decreased as the amount of shrimp powder in the formulation increased, whereas the a values was increased. Furthermore, hardness was significantly increased as the level of shrimp powder increased. In terms of overall acceptability, the preferred tofu samples were the control and that containing 2.0% shrimp powder addition group.

• 동아시아식생활학회지
• /
• 제19권3호
• /
• pp.401-408
• /
• 2009

The purpose of this study was to investigate the quality characteristics of Maejakgwas prepared with different concentrations of shrimp powder (0, 1, 2, 3, 4%) substituted for flour as a snack food for kindergarteners. The pH of the Maejakgwas dough decreased significantly as the level of shrimp powder increased; however, there were no significant differences in dough values among the test groups. Furthermore, the spread factor values of the groups were found to be inversely proportional to the shrimp powder concentration. Hunter's color L, a and b values decreased significantly as the level of shrimp powder increased. Moreover, the 2~4% shrimp powder groups had increased levels of hardness, cohesiveness, springiness, and brittleness when compared to the control. Finally, an acceptance test, the Maejakgwas sample containing 3% shrimp powder received the highest scores.

• Asian-Australasian Journal of Animal Sciences
• /
• 제24권8호
• /
• pp.1136-1141
• /
• 2011

Effect of dietary essential oils on growth, feed utilization and meat yields of white leg shrimp L. vannamei was investigated. White shrimp fry weighing 0.62 g were kept in one of 12 tanks (75 head/500 L holding tank) in a closed recirculation system. Four experimental diets, a commercial diet (control), phytoncide oil (PO), oregano oil (OO) and fermented garlic liquid (GL) were fed for 16 weeks. The mean water quality values for the whole experimental period were $27.8{\pm}1^{\circ}C$, $7.6{\pm}0.3$, $15.5{\pm}0.3$ g/L and $6.1{\pm}0.3$ mg/L for water temperature, pH, salinity and dissolved oxygen, respectively. At the end of the trial, 10 shrimp per tank were randomly sampled and meat yields (%) were evaluated after peeling the shell and removing the head. After a 16 week feeding trial, final weight of shrimp ranged from 21.9 g to 23.6 g. Feed conversion was not significantly different among groups (p>0.05), which was the lowest (1.95) in the control and highest (2.30) in the PO. Specific growth rate was also not significantly different (p>0.05) and ranged from 3.18% to 3.25%. Average daily gain of 0.2 g was obtained in all treatments. Mortality varied from 35.1% for control to 44.9% for OO. Meat yields maintained constant at 52.1% for control to 53.0% for PO. The study suggested that natural essential oils could not exert any improvement in growth performance, mortality and meat yields of white leg shrimp.

• 한국수산과학회지
• /
• 제37권2호
• /
• pp.91-97
• /
• 2004

Applications of probiotics to shrimp ponds were carried out to determine their effects on water quality. Fermented solutions consisting of Bacillus spp. and Nitrosomonas spp. were applied to a 4 ha shrimp (Fenneropenaeus chinensis) pond from July to September, 2000. In the pond treated with probiotics, daily variations of DO and pH, and concentrations of DIN and DIP were lower than those in the ponds without probiotic treatment. Concentration of phytoplankton was less variable and the number of species was more variable in the probiotic-treated pond than those in the control pond. Variation of bacterial numbers and the number of Vibrio spp. were lower in the treated pond than those in the control pond. It is confirmed that the probiotics can be used to improve water quality of the shrimp ponds.

• 한국수산과학회지
• /
• 제55권6호
• /
• pp.960-966
• /
• 2022

We aimed to determine the dietary myo-inositol (MI) requirements of Pacific white shrimp Litopenaeus vannamei. A basal diet was formulated without myo-inositol (M0) and a negative control diet (M0-) was prepared by adding tetracycline hydrochloride to the basal diet to prevent intestinal inositol synthesis. Five MI diets were prepared by adding MI at 300, 600, 900, 1,200 and 1,500 mg/kg to the basal diet (designated as, M300, M600, M900, M1200 and M1500, respectively). Triplicate groups of shrimp (initial body weight, 0.55±0.01 g) were fed one of the experimental diets for 42 days. The growth performance of shrimp in M0- group was significantly lower when compared to that of shrimp in M0, M1200 and M1500 groups. Feed efficiency was significantly improved in M1200 and M1500 groups when compared to the M0 and M0- groups. GPx activity was significantly higher in M1200 and M1500 groups compared to that in M0 and M0- groups. Therefore, a practical diet (over 240 mg/kg) meets the minimum MI requirements of Pacific white shrimp. However, the optimum dietary MI level would be potentially above 1,200 mg/kg for better feed utilization efficiency and antioxidant capacity of Pacific white shrimp.

• 한국식생활문화학회지
• /
• 제24권2호
• /
• pp.199-205
• /
• 2009

The purpose of this study was to investigate the quality characteristics of cookies prepared with shrimp powder (0, 3, 5, 7, 9%) substituted for flour as a snack food for Kindergarteners. The pH of the cookie dough decreased significantly in response to the addition of all levels of shrimp powder. However, there were no significant differences in the dough values among the test groups. Furthermore, when the spread factor values were compared among groups, they were found to be inversely proportional to the shrimp powder concentration. In addition, the Hunter's color L, a and b values decreased significantly as the level of shrimp powder increased. Moreover, the addition of 3${\sim}$9% shrimp powder resulted in increased hardness, cohesiveness, springiness, and brittleness when compared to the control. Finally, the results of acceptance test showed that the cookies containing 5% shrimp powder had the highest scores.