scholarly journals Feeding of masu salmon Oncorhynchus masou in the Okhotsk Sea in autumn

2016 ◽  
Vol 187 (4) ◽  
pp. 226-232
Author(s):  
Alexander Ya. Efimkin
Keyword(s):  
Diet Composition ◽  
Feeding Habits ◽  
Masu Salmon ◽  
Okhotsk Sea ◽  
Oncorhynchus Masou ◽  
Fall Season ◽  
Main Prey ◽  
Main Maximum ◽  
Minor Peak ◽  
Masu Salmon Oncorhynchus Masou

Feeding habits of masu salmon Oncorhynchus masou in the Okhotsk Sea is investigated. Its main prey in fall season is fish, amphipods, and euphausiids. However, the diet composition depends on the area: for masu with size of 30-40 cm it is mainly fish in the biostatistical districts 8 and 11 and zooplankton in other areas; besides, the zooplankton prey is replaced by fish for elder and larger salmons. The stomach fullness has significant circadian rhythm with one main maximum (70-700 ‱) and one minor peak. The main maximum was observed at 21 o’clock in 2002 but at 15 o’clock in 2006 and at 18 o’clock in 2009 and 2015 (local time).

Changes of serum growth hormone and vitellogenin levels during vitellogenesis in female masu salmon Oncorhynchus masou

2000 ◽  
Vol 66 (4) ◽  
pp. 789-791 ◽  
Author(s):  
Haruhisa Fukada ◽  
Naoshi Hiramatsu ◽  
Makiko Kitamura ◽  
Munetaka Shimizu ◽  
Akihiko Hara
Keyword(s):  
Growth Hormone ◽  
Masu Salmon ◽  
Oncorhynchus Masou ◽  
Serum Growth Hormone ◽  
Masu Salmon Oncorhynchus Masou

Molecular cloning of cDNAs encoding two types of gonadotrophin α subunit from the masu salmon, Oncorhynchus masou: construction of specific oligonucleotides for the α1 and α2 subunits

1993 ◽  
Vol 11 (3) ◽  
pp. 265-273 ◽  
Author(s):  
K Gen ◽  
O Maruyama ◽  
T Kato ◽  
K Tomizawa ◽  
K Wakabayashi ◽  
...  
Keyword(s):  
Amino Acids ◽  
Structural Difference ◽  
Structural Features ◽  
Masu Salmon ◽  
Time Interval ◽  
Oncorhynchus Masou ◽  
Α Subunit ◽  
Polymerase Chain ◽  
Fossil Records ◽  
Masu Salmon Oncorhynchus Masou

ABSTRACT Two types of cDNA (GTHα1 and -α2) encoding the α subunits of masu salmon (Oncorhynchus masou) gonadotrophin were cloned by the reverse transcription-polymerase chain reaction for pituitary mRNAs. The nucleotide sequences showed that the GTHα1 cDNA was 380 bp long, encoding 119 amino acids, and that GTHα2 cDNA was 365 bp long, encoding 114 amino acids. The masu salmon α subunit types had a few differences between the sequences, with homologies of 80% (nucleotide sequence) and 72% (amino acid sequence). The structural difference between the α1 and α2 subunits was predicted using hydropathic analysis. The evolutionary interval between masu and chum salmon was estimated to be 4·0 and 2·3 million years by comparing their GTHα1 and -α2 subunits respectively. These time values are roughly consistent with the evolutionary time interval (3·0 million years) estimated from fossil records and an isozyme study. Specific synthetic oligonucleotide probes were constructed and used for genomic Southern blot analyses. The restriction fragment sizes of the GTHα1 and -α2 genes were similar, and when their patterns were compared with those from four other teleosts, each species showed a different pattern from the others, but no difference between their respective α1 and α2 genes. Therefore, the structural features of the GTHα1 and -α2 genes may have diverged in a similar manner in these five teleosts.

Interaction between neuropeptide Y immunoreactive neurons and galanin immunoreactive neurons in the brain of the masu salmon, Oncorhynchus masou

2009 ◽  
Vol 462 (1) ◽  
pp. 33-38 ◽  
Author(s):  
Masafumi Amano ◽  
Noriko Amiya ◽  
Mikiko Hiramatsu ◽  
Takuma Tomioka ◽  
Yoshitaka Oka
Keyword(s):  
Neuropeptide Y ◽  
Masu Salmon ◽  
Oncorhynchus Masou ◽  
The Brain ◽  
Masu Salmon Oncorhynchus Masou

Phylogeography of a salmonid fish, masu salmon Oncorhynchus masou subspecies‐complex, with disjunct distributions across the temperate northern Pacific

2019 ◽  
Vol 65 (4) ◽  
pp. 698-715 ◽  
Author(s):  
Shoichiro Yamamoto ◽  
Kentaro Morita ◽  
Takeshi Kikko ◽  
Kouichi Kawamura ◽  
Shunpei Sato ◽  
...  
Keyword(s):  
Masu Salmon ◽  
Salmonid Fish ◽  
Oncorhynchus Masou ◽  
Northern Pacific ◽  
Masu Salmon Oncorhynchus Masou

Ultrastructural changes in gill chloride cells during smoltification in wild and hatchery-reared masu salmon Oncorhynchus masou

2000 ◽  
Vol 66 (4) ◽  
pp. 670-677 ◽  
Author(s):  
Shinya Mizuno ◽  
Kazuhiro Ura ◽  
Tadashi Okubo ◽  
Yuka Chida ◽  
Naoyuki Misaka ◽  
...  
Keyword(s):  
Masu Salmon ◽  
Ultrastructural Changes ◽  
Chloride Cells ◽  
Oncorhynchus Masou ◽  
Masu Salmon Oncorhynchus Masou
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