• Korean Journal of Animal Reproduction
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• v.21 no.3
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• pp.311-319
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• 1997

This study was carried out to investigate the ultrastructural changes of spermatozoa obtained from 20 of 3-year-old male chum salmon(Oncorhynchus keta) collected and analysed in middle October in 1995. The ultrastructural changes of gonad of fingerlings were examined to describe the sex differentiation of this species. The results obtained in this study were as follows : In spermatozoa, the nucleus is dense and homogeneous. Two spheroidal mitochondria(about 350nm long) are situated in parallel between the nucleus and the axoneme. Spermatozoa mitochondria are assembled into an organized sheath surrounding the outer dense fibres and axoneme of the flagellar midpiece. The sheath flagellum is situated beneath the base of the sperm head. The primordial germ cells of 6.8~7.2${\mu}{\textrm}{m}$ in size, which were buried under fibrous mesenchymal tissue between gut duct and notochord of larva with a total length of 2.4cm at 50 days after hatching. In juvenile of 10.5cm in total length at 70 days after hatching, the gonad was occupied by bundles of oogonia. The dense drumstick bodies(large arrows) are observed in the nuclei of the primordial gonad and surrounding tissue cells of fingerling at 70 days after hatching. The oval Barr bodies(asterisk) are observed in the nuclei of the primordial germ cells under the mitosis(2n). Note the large mitochondria, ribosomes and rough endoplasmic reticulum in the cytoplasm. Accordingly, the fingerlings at 70 days after hatching are identified as the female(xx). In result, the gonadal sex differentiation begins from the 70 days after hatching in chum salmon.

• Korean Journal of Community Nutrition
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• v.11 no.5
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• pp.642-649
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• 2006

The purposes of this study were to investigate methods of applying activity-based cost to menu engineering and to examine the feasibility. A total of 6 menu items of XYZ restaurant in Seoul were selected and the ledger of September 2005 was used for menu analysis. The menu mix percent of beef sirloin steak (61.95%) and beef tenderloin steak (17.13%) were labeled as high, whereas BBQ pork ribs (4.94%), salmon fillet (2.66%), seafood platter (5.77%), and teriyaki chicken (7.56%) showed low menu mix percent. In addition, the contribution margin for BBQ pork ribs (29,000 won), salmon fillet (25,810 won), seafood platter (22,400 won), and teriyaki chicken (22,000 won) were higher than the average contribution margin (21,957 won), and those for beef sirloin steak (21,200 won) and beef tenderloin steak (21,900 won) were lower than average. When popularity and contribution margin were applied in menu engineering, BBQ pork ribs, salmon fillet, seafood platter and teriyaki chicken were classified as puzzles and beef tenderloin steak and beef sirloin steak as plowhorses. Menu engineering using popularity and operating profit, which was calculated from activity-based cost, also gave the same results, whereas the additional label for activity cost placed BBQ pork ribs and salmon fillet in the brain teaser category. Ranking analysis on variables estimating menu profitability using Spear-man's ${\rho}$ revealed that there were no significant correlation between variables, which means the estimation of menu item profitability could differ by methods of analysis. With these results, it was concluded that activity-based cost would help to establish more detailed marketing strategy for a restaurant.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.1
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• pp.118-123
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• 2021

This study was conducted to evaluate plant proteins as a replacement for a fishmeal diet in the rearing of coho salmon Oncorhynchus kisutch. Twelve groups of 20 fish averaging 34.0±0.62 g were randomly distributed into 12 rectangular tanks (250 L). Four experimental diets included a control diet containing 60% fishmeal (Control), and three other diets that replaced 20% of fishmeal with soy protein concentrate (SPC), fermented soybean protein concentrate (F-SPC), and enzyme-processed soy protein concentrate (E-SPC). At the end of the feeding trial, fish that were fed Control, SPC and E-SPC diets showed significantly higher weight gain, specific growth rate, feed efficiency, and protein efficiency ratio than those that were fed F-SPC diet. However, there were no significant differences among the fish that were fed Control, SPC, and E-SPC diets. No significant differences were observed in crude protein, crude lipid, and ash of whole body among the fish that were fed all the diets. Therefore, these results indicated that 20% of fishmeal could be replaced by E-SPC or SPC without any adverse effects on the growth performance of coho salmon.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.10
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• pp.1326-1333
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• 2007

For preparing the basic ingredients of Gomtang-like products from the extracts of salmon frame, the extraction conditions of salmon frame were examined, and the characteristics of the extracts were compared with commercial Gomtang. Based on the crude protein, Ex-N and sensory attributes, the extractions were optimized by extracting pretreated-salmon frame in 12 times (v/w) of water for 12 hrs, before filtering with cheese cloth to yield 3 times the volume of the raw material. The concentrations of heavy metals in extracts from salmon frame were below the safety limits suggested by KFDA. The mai or amino acids were glutamic acid and aspartic acid as the free amino acids, and glycine, proline, and glutamic acid as the total amino acids. The calcium and phosphorus contents were 18.0 mg/100 mL and 33.1 mg/100 mL, respectively, and they accounted for 20% and 18% of the recommended daily allowance for mineral intake. The angiotensin I converting enzyme (ACE) inhibitory activity was improved by incubation with Flavourzyme for 4 hrs and its $IC_{50}$ was 2 mg/mL. The results above suggested that the enzymatic hydrolysates from extracts of salmon frame could be used as a basic ingredient for preparing Gomtang-like products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.2
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• pp.223-230
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• 2008

For the use of extracts from salmon frame as a basic material of Gomtang-like products, various methods (soaking into soybean milk, adding anchovy, and adding spices) for masking fish odor into extracts from salmon frame were examined and the food component characteristics were also compared with commercial Gomtang. According to the results of volatile basic nitrogen, transmission at 660 nm and sensory evaluation of extracts, soaking treatment, which is the soaking of salmon frame into soybean milk, was the most efficient method among the various methods for masking fish odor into extracts from salmon frame. There was no difference in the proximate composition between extracts from salmon frame soaked (FS) and unsoaked (C) into soybean milk. The FS was not detected in heavy metals, such as chromium, lead and cadmium. The taste value of FS (16.26) was higher than that of C and the major amino acids were glutamic acid and aspartic acid. Total amino acid content of FS (3.08 g/100 mL) was also higher than those of C (2.95 g/100 mL) and commercial Gomtang (1.70 g/100 mL), and the major amino acids were glycine, proline, glutamic acid and arginine. The calcium and phosphorus contents of FS/500 mL accounted for 21.7% and 18.5%, respectively, of the recommended daily allowance of mineral for adult.

• Korean Journal of Ichthyology
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• v.2 no.2
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• pp.211-216
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• 1990

Mitotic analyses of the coho salmon (Oncorhynchus kitsuch) revealed a mode of 2n=60 whit 46 meta or submetacentric and 14 acrocentric chromosomes (NF=106). Individuals with 2n=61 were also found in both sexes in the same population; the karyotype is composed of 45 meta or submetacentric and 16 acrocentric chromosomes (NF=106). This result may indicate that Robertsonian chromosomal polymorphism occurred in the population of the coho salmon.

• Development and Reproduction
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• v.24 no.3
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• pp.241-248
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• 2020

This study used a PCR-based genetic analysis platform to create a hierarchical polar dendrogram of Euclidean genetic distances for two salmonid species, Oncorhynchus mykiss (rainbow trout, RT) and Oncorhynchus masou (masu salmon, MS). The species were distantly related to other fish species based on PCR results from using the designed oligonucleotide primer series. Five oligonucleotide primers were used to generate 330 and 234 scorable fragments in the RT and MS populations, respectively. The DNA fragments ranged in size from approximately 50 bp to more than 2,000 bp. The bandsharing (BS) results showed that the RT population had a higher average BS value (0.852) than that for the MS population (0.704). The genetic distance between individuals supported the presence of adjacent affiliation in cluster I (RT 01-RT 11). The observation of a significant genetic distance between the two Oncorhynchus species verifies that this PCR-based technique can be a useful approach for individual- and population-based biological DNA investigations. The results of this type of investigation can be useful for species safekeeping and the maintenance of salmonid populations in the mountain streams of Korea.

• Journal of fish pathology
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• v.31 no.1
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• pp.1-8
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• 2018

Causative agent of infectious hematopoietic necrosis (IHN) belonging to genus Novirhabdovirus (Rhabdoviridae). Economic losses caused by IHNV are serious in mainly Oncorhynchus spp. including rainbow trout O. mykiss and Atrantic salmon Salmo salar. IHNV was initially found by endemic presence in U.S. West Coast for sockeye salmon fry O. nerka and chinook salmon fry O. tshawytscha in the 1950s, and it has spread to Japan, Korea and Taiwan in the 1970s, and also to Italy and France in the 1990s. Currently, IHNV is detectable in many parts of the world, including Russia and South America. Mortality due to IHNV infection in fish with ${\leq}0.5g$ of body weight reaches 60% to 100%, while the mortality reduces by fish growing. In recent years, onset of IHNV infection has increased also in fish with large sizes. Here, we introduce molecular epidemiology and virulence changes of IHNV in East Asia, furthermore, we discuss on future prospects in IHNV researches.

• Journal of fish pathology
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• v.31 no.2
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• pp.57-70
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• 2018

Infection with salmonid alphavirus (SAV) is a serious disease that mainly affects rainbow trout (Oncorhynchus mykiss) and Atlantic salmon (Salmo salar L.) reared in seawater or freshwater. SAV is prevalent in European countries including Norway that exports rainbow trout and Atlantic salmon to Korea. Consequently, SAV was listed as a disease notifiable to the OIE and many salmonid-producing countries either designate SAV as their notifiable disease or do research on the development of diagnosis and epidemiology to reduce the possibility of SAV infection. Unlike other salmonid-producing countries, SAV is not listed as a notifiable disease in Korea, thereby arousing concern that SAV will get into the country through the importation of live salmonids. Under the circumstance, Korea needs to have a legal basis to take much stricter follow-up measures, including listing SAV as a notifiable disease, establishing surveillance system based on OIE standards to declare Korea free from SAV, killing infected fish and conducting fallow system against affected farms.

• Korean Journal of Agricultural Science
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• v.48 no.2
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• pp.191-199
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• 2021

Salmon oil (SO) could be used as a great source of ω-3 fatty acids in pig diet. The purpose of the study was to investigate the SO effect on production performance of sows and their offspring. 48 lactating sows (Landrace × Yorkshire) from Dankook University experimental farm were used in this study. Sows were conceived using either guided natural mating or by artificial insemination. Pregnancy diagnosis was confirmed by ultrasonography on day 25 after mating. Sows and their offspring were assigned randomly to 1 of 2 treatments. Treatments included: 1), control (CON); 2), control + SO 0.5% (CS). The inclusion of SO did not affect (p > 0.05) the litter size throughout the experiment. No difference (p > 0.05) was observed on the average daily feed intake (ADFI), chest circumference, estrus interval and sow backfat thickness between CON and SO treatments. Dietary SO supplemented diet reduced (p < 0.05) body weight loss during lactation compared with control treatment. Pigs fed SO supplemented diet did not affect (p > 0.05) the fecal scores during lactation compared with those fed control treatments. Sows fed SO supplemented diet led to a higher (p < 0.05) initial weight, weaning weight and average daily gain of piglets than those fed control diets. No difference (p > 0.05) was observed on piglet survival and fecal scores throughout the experiment. Inclusion of SO could reduce the body weight loss of sows and improves piglet growth during lactation, indicating SO has beneficial effects for pigs.