Comparative Early Developments in Winter Spawned Three Pre-larval Fishes (Gadus macrocephalus, Liparis tanakae, Hexagrammos agrammus)

Shin, Min Gyu; Lee, So-Gwang; Lee, Jeong-Tae; Gwak, Woo-Seok

doi:10.35399/isk.30.1.2

Cited by 1 publication

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The fish larvae stage represents the stage with the highest vulnerability in a fish life cycle [40][41][42]. Initial mass mortality occurs internally due to the drastic development of organs, including the digestive and swimming organs necessary for the primary nutrient source shifts from endogenous reserve to exogenous feeding [43] and externally due to starvation and predation [44]. Therefore, in order to increase seed production in a culture environment, it is important to provide an optimal rearing protocol with an understanding of the change of internal factors.…”

Section: Discussionmentioning

confidence: 99%

Morphological and Allometric Changes in Anguilla japonica Larvae

Shin

Ryu

Choi

et al. 2022

Biology

View full text Add to dashboard Cite

The freshwater eel Anguilla japonica is rapidly decreasing in number and has not yet been successfully mass produced. This may be at least partially attributable to the unique and long early life history of the eel. Therefore, we investigated its ontogeny of morphometry and growth pattern in larval stages to provide baseline information for understanding the early life history and improving seed rearing technology. This study was conducted for 200 days after hatching (DAH) and analyzed morphometry and allometry for eel larvae. The following cultured eel larval stages were identified: the yolk sac larvae stage (0–6 DAH, 3.23–6.85 mm total length (TL)), the pre-leptocephalus stage (7–30 DAH, 6.85–15.31 mm TL), and the leptocephalus stage (50–200 DAH, 15.31–60.06 mm TL). Cultured and wild eel larvae could be divided into characteristic larval stages at similar sizes. However, compared to wild eels, cultured eels had a slower growth rate and fewer preanal myomeres. Meanwhile, cultured eel larvae rarely had a mixed feeding period as the absorption of endogenous reserves was completed by 7 DAH. The lower jaw of eel larvae was significantly longer than the upper jaw from 50 DAH. In the pre-leptocephalus and leptocephalus stages, eel larvae showed continuous positive allometric growth at trunk height and tail muscle height with change to the willow leaf-like form. These growth characteristics may be the result of adaptation to the migration over long distances and to a diel vertical migration. The inflection point in the body parts growth patterns showed only before 30 DAH, and mass mortality appeared at this period. Therefore, to improve the growth and survival rates of cultured eel seed, it is necessary to focus on improving the feeding and rearing protocol until 30 DAH.

show abstract