• Journal of Aquaculture
• /
• v.13 no.1
• /
• pp.39-46
• /
• 2000

Successive management of prawn farm is strongly dependent upon monitoring of pond seawater quality which is generally influenced by an excessive food supplied sediment type and phytoplankton composition in the pond. For good condition of seawater quality it must need exchangning of fresh seawater by tidal current. Two distinct shrimp ponds Galha and Yunho which were different in seawater exchanging system and sediment type were selected to understand how some factors affected to seawater and sediment qualities in the pond. Prawn growth was also determined. Galha pond characterized by sand bottom with water exchanging by turn of the tidal current accumulated 1.8 mgS/g-dry as sulfide in sediment while Yunho pond mud- bottomed with seawater exchanging of pumping system showed 4.7mgS/g-dry when it was highest, Ammonia-N and hydrogen sulfide measured in the seawater were 0.31mg/${\ell}$ and 21.2 ${\mu}$${\ell}$/${\ell}$in Yunho and 0.10mg/${\ell}$and 10.8${\mu}$${\ell}$/${\ell}$in Galha pond respectively. Dissolved oxygen remained below 6.0mg/${\ell}$ in Galha and 5.0mg/${\ell}$in Yunho pond from June through August. Less growth of prawn was found in Yunho pond than in Galha pond. Prawn growth expressed as body length and weight were 138.3mm 22.9g in Yunho pond while they were length 158.2mm and 28.9g in Galha pond respectively when they were harvested in October. These results indicate that higher levels of ammonia-N and hydrogen sulfide and lower dissolved oxygen in bottom seawater of Yunho pond might affect the growth of cultured prawn.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.20 no.5
• /
• pp.455-460
• /
• 1991

In order to identify hard distinct 12 fish species(shiba shrimp Metapenaeus joyneri, fleshy shrimp Penaeus orientalis, ridgetail prawn Palaemon carinicauda, yellow croaker Pseudosciaena manchurica, croaker Niber albiflora, Colichthyes fragilis, brown sole Limanda herzensteini, frog flounder Pleuronichthys cornutrs, Areliscus rhomaleus, stone flounder Kareius bicoloratus, harvest fish Pampus argenteus, flag fish Goniistius zonatus) by seeing with naked eye in Kunsan coastal area, sarcoplasmic protein in the supernatant was used for isoelectric focusing. For getting supernatant, fish muscle tissue was blended with two times deionized water and centrifuged (at $4^{\circ}C$, 12,000rpm for 15min). Isoelectric focusing of sarcoploasmic protein carried out on a LKB Multiphor II using polyacrylamide gel plate (2mm thickness, pH $3.5~10^{\circ}C$, pH 5~8 gradient, at $10^{\circ}C$ for 1.5, 3 hours). In case of uncertain protein pattern, pH gradient was modified to narrow pH gradiet, and excuted 2-D electrophoresis using conventional polyacrylamide gel electrophoresis. Most of fishes except yellow croaker and Collichthyes fragilis were distingushed by isoelectric focusing. The protein maps of 2-D electrophoresis for analyzing two protein bands at aimilar positions(pH 5, 6) between the two fish species showed the diffeences of the estimated molecular weights, 11,700(pH5.0) and 87,000(pH6.0)

• Fisheries and Aquatic Sciences
• /
• v.26 no.11
• /
• pp.649-659
• /
• 2023

The present study compared the structure of mixilliped of Fenneropenaeus chinensis between the larval and adult stage and investigated the effect of the structural difference on the immunity of F. chinensis. A fourteen day and a one-month long culture trial were conducted each with postlarvae and adults of F. chinensis in the biofloc, mixed water (50% biofloc:50% clear seawater) and seawater control. Immune-related genes mRNA expressions of postlarvae was analysed by quantitative reverse transcription polymerase chain reaction (qRT-PCR). And the analysis of adult stage immunity was carried out using phenoloxidase (PO) enzyme activation in haemocyte. In the postlarvae, the final body weights were 51.43 and 58.47 mg for the biofloc water and the control seawater, respectively. On the other hand, the final body weights of the adults were significantly different between biofloc water and seawater. The survival rate showed the opposite trend to the growth rate. Immune related genes mRNA expression levels in the postlarvae in the biofloc water were significantly lower than those in the seawater. While, the adult stage showed significantly higher PO enzyme activations in the biofloc water than in the seawater with the PO enzyme activation increasing proportionally to the biofloc concentration. This result is considerably explained by the observations of setal morphological structures of the third maxilliped: postlarvae have short serrulated setae that compose the small 'net' structure while adults had long and dense plumose setae. It is understood that the morphological difference of the maxilliped structure resulted in the different feeding abilities in the postlarvae and the adult F. chinensis to use bioflocs as food source.