TY - JOUR
T1 - Fine structure and differentiation of the alimentary canal in captive-bred Japanese eel Anguilla japonica preleptocephali
AU - Ozaki, Yuichi
AU - Tanaka, Hideki
AU - Kagawa, Hirohiko
AU - Ohta, Hiromi
AU - Adachi, Shinji
AU - Yamauchi, Kohei
N1 - Funding Information:
We thank our colleagues in the eel research group of Hokkaido University for their encouragement. This study was supported by grants from the Fisheries Agency, from the Japan Society for the Promotion of Science, and from the 21st Century COE program ‘Marine Bio-Manipulation Frontier for Food Production’ of the Ministry of Education, Culture, Sports, Science and Technology of Japan.
PY - 2006/2
Y1 - 2006/2
N2 - The fine structure of the alimentary canal in preleptocephali produced by artificially matured Japanese eel was examined. At 1 day posthatch (dph), the alimentary canal was found only above the dorsal side of the yolk mass, and the epithelium was composed of a single layer of epithelial cells. By 5 dph, the alimentary canal was divided into three segments based on the structure of the epithelial cells: foregut, midgut and hindgut, corresponding to the future esophagus, intestine and rectum, respectively. After 7 dph, the epithelium in the foregut was surrounded by a circular muscle layer, suggesting a role in the transportation of food materials. The epithelial cells of the midgut exhibited well-developed membranous structures, which are deduced to be invaginations of the cytoplasmic membrane. Pinocytotic invaginations and vacuoles were observed in the epithelial cells of the hindgut; this observation suggests that this region is involved in the uptake of food. Significant changes in morphological features of the epithelial cells in each segment were observed until 7 dph; however, these were not evident between 7 dph and 13 dph. Consequently, the differentiation of the alimentary canal was completed by 7 dph, and preleptocephalus had developed the ability to absorb food by 7 dph.
AB - The fine structure of the alimentary canal in preleptocephali produced by artificially matured Japanese eel was examined. At 1 day posthatch (dph), the alimentary canal was found only above the dorsal side of the yolk mass, and the epithelium was composed of a single layer of epithelial cells. By 5 dph, the alimentary canal was divided into three segments based on the structure of the epithelial cells: foregut, midgut and hindgut, corresponding to the future esophagus, intestine and rectum, respectively. After 7 dph, the epithelium in the foregut was surrounded by a circular muscle layer, suggesting a role in the transportation of food materials. The epithelial cells of the midgut exhibited well-developed membranous structures, which are deduced to be invaginations of the cytoplasmic membrane. Pinocytotic invaginations and vacuoles were observed in the epithelial cells of the hindgut; this observation suggests that this region is involved in the uptake of food. Significant changes in morphological features of the epithelial cells in each segment were observed until 7 dph; however, these were not evident between 7 dph and 13 dph. Consequently, the differentiation of the alimentary canal was completed by 7 dph, and preleptocephalus had developed the ability to absorb food by 7 dph.
KW - Alimentary canal
KW - Fine structure
KW - Japanese eel
KW - Preleptocephalus
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U2 - 10.1111/j.1444-2906.2006.01110.x
DO - 10.1111/j.1444-2906.2006.01110.x
M3 - Article
AN - SCOPUS:33645060779
SN - 0919-9268
VL - 72
SP - 13
EP - 19
JO - Fisheries Science
JF - Fisheries Science
IS - 1
ER -