• 한국수산과학회지
• /
• 제52권6호
• /
• pp.735-739
• /
• 2019

The purpose of this study was to measure pH, trimethylamine (TMA), and total volatile basic nitrogen (TVB-N) as indicators of freshness during largehead hairtail Trichiurus lepturus storage, and to compare these indicators with those obtained by the sensory evaluation of quality index method (QIM) sensory evaluation. Largehead hairtail samples were stored at 4℃ and evaluated every 3 days until decay. The QIM sensory evaluation indicated scores of 0, 8.9, and 20 on storage days 0, 6, and 20, respectively. By day 15, the samples were completely decayed. The pH slowly increased during the storage period, reaching a maximum of 7.4. In the day 6, TMA and TVB-N contents were 2.97 and 15.57 mg/100 g, respectively. Thus, at 4℃, the largehead hairtail starts to decay after 6 days and, after 9 days, cannot be consumed safely

• 한국수산과학회지
• /
• 제44권6호
• /
• pp.695-700
• /
• 2011

Age, growth, and maturity of Trichiurus lepturus were estimated based on right-handed sagittal otoliths belonging to 1,031 fish collected from January to December 2007 in the East China Sea. The outer margins of the otolith were examined and showed that an opaque zone was formed once per year. Marginal increments in otoliths formed as annual rings between June and August, at the beginning of the spawning season. Fish growth was expressed by the von Bertalanffy growth equation, as follows: $L_t=494.0$ ($1-e^{-0.2453(t+-0.4822)}$) for females and $L_t=330.4$ ($1-e^{-0.4292(t+0.7513)}$) for males, where $L_t$ is the total length in mm and t is age in years. The growth rates of males and females were significantly different (P<0.05).The age composition ranged mostly between ages 2 and 4, and the oldest individuals were 4 years old in males and 6 years old in females. Finally, the age composition of largehead hairtail was compared with data from the 1970s and is discussed in the context of environmental changes.

• Fisheries and Aquatic Sciences
• /
• 제12권2호
• /
• pp.152-161
• /
• 2009

The largehead hairtail (Trichiurus lepturus) is one of the most common fisheries stocks in the East China Sea and the Yellow Sea. The species is caught using a variety of fishing tools, such as a stow net or a long line, as well as jigging and trawling. Scientific investigations have been conducted throughout the world to enable evidence-based estimations for the management and protection of the main fisheries biomass. For example, inshore and offshore hydro acoustic surveys are performed annually using bottom- and mid-water trawls around the Korean Peninsula. However, to date, no acoustic survey has been conducted to estimate fish size distribution, which is necessary to construct a data bank of target strength (TS) relative to fish species, length (L), and frequency. This study describes the frequency and length dependence of TS among fishes in Korean waters for the purpose of constructing such a TS data bank. TS measurements of the largehead hairtail were carried out in a water tank (L 5 m$\times$width 6 m$\times$ height 5 m) at frequencies of 50, 75, 120, and 200 kHz, using a tethering method. The average TS patterns were measured as a function of tilt angle, ranging from $-45^{\circ}$ (head down) to $+45^{\circ}$ (head up) every $0.2^{\circ}$. The length conversion constant ($b_{20}$) was estimated under the assumption that TS is proportional to the square of the length. In addition, in situ TS measurements on live largehead hairtails were performed using a split beam echo sounder.

• 한국어류학회지
• /
• 제17권3호
• /
• pp.173-186
• /
• 2005

한국과 대서양산 갈치 (Trichiurus lepturus) 2지리적 집단으로부터 genomic DNA를 분리 추출하였다. 선택된 8개의 RAPD primer를 이용하여 common, polymorphic 그리고 specific fragment를 얻어냈다. 2지역으로부터 primer간 banding patterns 의 복잡성이 두드러지게 나타났다. DNA fragment 의 분자적 크기는 150 bp에서부터 3,000 bp까지 커다란 차이를 나타내었다. 본 연구에서 한국산 갈치 집단에서는 947개의 fragment가 나타났고, 대서양산 갈치 집단에서는 642개의 fragment 가 확인되었다. 또한 한국산 집단에서는 148개의 specific fragment (15.6%) 가 확인되었으며, 대서양산 갈치집단에서는 61개의 specific fragment (9.5%)가 발생되었다. 한국산 갈치집단에서는 638개의 common fragment가 나타났으며, 이는 primer 당 평균적으로 79.8개의 fragment 로 확인되었다. 또한 대서양산 갈치집단에서는 429개의 common fragment 가 확인되었고, 평균해서 primer 당 53.6개의 common fragment 가 나타났다. 한국산 갈치집단과 대서양산 갈치집단의 polymorphic fragment는 각각 76개와 27개로 확인되었다. 모든 갈치시료의 평균적인 bandsharing value를 기초로 해서 한국산 갈치집단의 similarity matrix를 조사해 본 결과 0.784 로부터 0.922까지 나타났고, 대서양산 갈치집단의 값은 0.833로부터 0.990까지 확인되었다. 결과적으로 대서양산 갈치집단내 개체의 bandsharing value 평균값은 한국산 갈치집단의 평균값보다 높게 나타났다. 8개의 primer를 사용하여 얻어진 dendrogram은 cluster 1 (KOREAN 01~KOREAN 11) 및cluster 2 (ATLANTIC 12~ATLANTIC 22)와 같이 2개의 유전적 클러스터로 나뉘어졌다. 한국산 갈치집단내의 10번째 개체(KOREAN no. 10)와 11번째 개체(KOREAN no. 11) 사이가 가장 가까운 유전적 관계(genetic distance = 0.038)를 나타내었다. 궁극적으로 볼 때 한국산 갈치집단의 1번째(KOREAN no. 01)와 대서양산 갈치집단의 16번째(ATLANTIC no. 16) 개체 사이가 가장 먼 유전적 거리(genetic distance = 0.708)를 나타내었다.

• 수산해양기술연구
• /
• 제60권1호
• /
• pp.1-8
• /
• 2024

This study examined the power consumption of angling boats during entry, departure, and fishing operations using a black box-type storage device. Through this analysis, it determined the energy consumption and carbon emissions of small fishing boats used for catching the largehead hairtail. The energy consumption and carbon emissions were calculated using formulas provided by the Korea Energy Agency, which incorporated updated emission coefficients from 2022. The findings revealed that the average power consumption of small fishing boats for the largehead hairtail was 546.3 kWh, with a total energy consumption of 0.1164 TOE and carbon emissions of 24.057 CO₂. The average energy consumption was calculated at 0.0006 TOE per kilogram, and the carbon emissions were determined to be 0.135 CO₂/kg.

• 한국해양생명과학회지
• /
• 제7권1호
• /
• pp.55-59
• /
• 2022

연구는 갈치 Trichiurus lepturus의 성 성숙과 생식생물학적 기초 정보를 제공하기 위해 수행하였다. 난자형성과정 동안 난모세포와 핵의 크기는 증가하였으나 핵에 대한 인의 비율은 감소하였다. H-E 염색 결과, 세포질의 염색성은 호염기성에서 호산성으로 변하였다. 난황형성개시기 난모세포의 난경은 약 63.2 (±12.7) ㎛였다. 세포질에서는 호산성의 난황핵이 관찰되었다. 성숙기 난모세포의 난경은 216.6 (±24.7) ㎛였으며, GVBD (germinal vesicle breakdown)가 관찰되었다. 완숙기 난모세포의 난경은 317.9 (±80.9) ㎛였으며, 방사대의 두께는 4.2 (±1.7) ㎛였다. 난모세포의 발달형태는 난군동기발달형에 속하며, 난황 축적은 대부분의 경골어류와 마찬가지로 외재적 방법과 내재적 방법에 의한 것으로 판단되었다.

• 수산해양기술연구
• /
• 제46권1호
• /
• pp.1-9
• /
• 2010

Experimental fishing was carried out to compare fishing status according to the codend mesh size (raschel, 15mm, 25mm, 35mm, 45mm) of stow net on anchor in the coastal waters of Seocheon after manufacturing five kinds of fishing gears and commercial fishing boat (7.93 tons) was used for it. Total catches of raschel, 15mm, 25mm, 35mm, 45mm codend were 816,949g, 203,994g, 1,405g, 51,576g, 194g in September and 40,545g, 66,974g, 14,692g, 12,647g, 12,655g in October. Dominance species were anchovy (Engraulis japonicus) in raschel codend, largehead hairtail (Trichiurus lepturus) in 15mm and 35mm in September, and the amount of catches was very small in 25mm and 45mm codend due to the fishing gear damage. In October, dominance species were anchovy and beka squid (Loligo beka) in raschel, 15mm, 25mm codend, and cuttlefish (Sepia esculenta) and beka squid were mainly caught in 35mm and 45mm codend. In addition, total length of anchovy and cardinal fish (Apogon lineatus) were increased according to the increase of codend mesh size but there was no difference in the mantle length of cuttlefish and loligo beka.