Welcome to FIS   Sponsored By
United States
Subscribe to FIS | Register with FIS | Advertise with FIS | Newsletter | About FIS | Contact us
   


Masu salmon specimen, Oncorhynchus masou. (Photo Credit: Apple2000)

How do fish know when to spawn?

Click on the flag for more information about Japan JAPAN
Thursday, July 04, 2013, 05:00 (GMT + 9)

Researchers have unprecedentedly discovered the mechanism through which fish are able to sense the seasons and when it is time to spawn.

Japanese scientists Nagoya University and from Utsunomiya University found that a previously puzzling area of the brain in salmon informs the fish of changes in the length of the day that come with each season.

The results of the study were published this week in the online British scientific journal Nature Communications.

The group of researchers analysed the masu salmon, whose stocks spawn in the autumn, to determine if seasonally breeding fish use a mechanism similar to that of birds and mammals, which have sensors that produce the secretion of hormones that grow testes as the days get longer, The Asahi Shimbun reports.

Appropriate conditions then turn on the production of reproductive hormones that induce fertility and tell the fish it is spawning season.

The researchers divided 20 salmon into two groups and raised them for two months, one group illuminated for 16 hours a day representing summer, and the other for eight hours a day representing winter. After subsequently examining the fishes’ brain tissue, it was found that an area called the saccus vasculosus behaved as a sensor for light.

Scientists then removed the saccus vasculosus from some fish and saw that the testes did not grow as expected in those fish under the artificial conditions and that certain hormones were not secreted.

This means that the saccus vasculosus serves as a sensor for fish to detect which season is approaching and, in the case of autumn, induce breeding, the scientists explained.

These findings regarding how exactly fish perceive seasons and how this affects their brains and hormonal activity may lead to improved breeding programmes and be applicable in other industries, said Takashi Yoshimura, a professor of animal physiology at Nagoya University and a member of the research group.

“It is well established that day length is the dominant seasonal cue for many organisms. But, temperature changes also affect the seasonality in some species. I would like to understand how animals sense changes in temperature to adapt to seasonal changes in environment,” Yoshimura added, according to Asian Scientist.

By Natalia Real
editorial@fis.com
www.fis.com


 Print


Click to know how to advertise in FIS
MORE NEWS
United Kingdom
Aug 28, 09:00 (GMT + 9):
IN BRIEF - Nomad Foods Limited Announces Financial Results for the Period Ended 30 June 2015
Iceland
Aug 28, 09:00 (GMT + 9):
IN BRIEF - Racing for Saithe before the year's end
Viet Nam
Aug 28, 03:20 (GMT + 9):
Vietnamese crab exports grow in first seven months
Mexico
Aug 28, 02:50 (GMT + 9):
Sonora first harvests yield 865 tonnes of shrimp
United Kingdom
Aug 28, 02:10 (GMT + 9):
Three vessels obtain first responsible fishing certificates
Spain
Aug 28, 01:30 (GMT + 9):
Nueva Pescanova future to be decided on 28 September
Worldwide
Aug 28, 00:50 (GMT + 9):
Shrimp trawling responsible for the highest bycatch
Argentina
Aug 27, 23:50 (GMT + 9):
INIDEP to train artisanal fishermen
United States
Aug 27, 23:30 (GMT + 9):
NOAA Fisheries unveils climate science strategy
India
Aug 27, 22:40 (GMT + 9):
IN BRIEF - Gambusia fish hatcheries set up in four places
Australia
Aug 27, 22:40 (GMT + 9):
IN BRIEF - Regulatory duplication strangling aquaculture development in Queensland
Singapore
Aug 27, 22:40 (GMT + 9):
IN BRIEF - No link found between GBS and sashimi consumption: MOH
Republic of Ireland
Aug 27, 22:40 (GMT + 9):
IN BRIEF - Ministry passes new decree on fishing net use in UAE
United States
Aug 27, 22:40 (GMT + 9):
DNA sequencing used to study fish spawning
United States
Aug 27, 22:30 (GMT + 9):
IN BRIEF - Fish farms could prompt lawsuit against government



Lenguaje
FEATURED EVENTS
  
TOP STORIES
Biotechnology developed to use onshore seaweed
Mexico A team of researchers from the National Fisheries Institute is working on the development of biotechnology for the use of seaweed on shore that is produced off Baja California peninsula coast.
Omega-3 supplements would not protect against brain decline
United States Researchers at the National Institutes of Health reached the conclusion that omega-3 supplements do not slow cognitive decline in the elderly despite offering benefits for eye, brain and heart health.
Shrimp sector reduction forecast
Ecuador In the first seven months of the year shrimp sales abroad generated revenues for USD 1,375 million, USD 2.6 million less than in the same period of 2014.
Spanish firm allocated fishing terminal construction in Montevideo
Uruguay The Spanish company Abengoa has been allocated the construction of a fishing terminal in Capurro area, Montevideo, which is building work that will require an investment of USD 93 million.
 
Maruha Nichiro Corporation
Nichirei Corporation -Headquarter-
Pesquera El Golfo S.A.
Ventisqueros - Productos del Mar Ventisqueros S.A
Wärtsilä Corporation -Wartsila Group Headquarter-
ITOCHU Corporation -Headquarter-
BAADER - Nordischer Maschinenbau Rud. Baader GmbH (Head Office)
Inmarsat plc - Global Headquarters
Marks & Spencer
Tesco PLC (Supermarket) - Headquarters
Pescanova, S.A. - Group Headquarters
Sea Harvest Corporation (PTY) Ltd.
I&J - Irvin & Johnson Limited
Blue Continent Products (Pty) Ltd - (Oceana Group Limited)
Pesquera San Jose S.A.
Nutreco N.V. - Head Office
CNFC China National Fisheries Corporation - Group Headquarters
W. van der Zwan & Zn. B.V.
SMMI - Sunderland Marine Mutual Insurance Co., Ltd. - Headquarters
Icicle Seafoods Inc. -Headquarter-
Starkist Seafood Co. - Headquearters
Trident Seafoods Corp.
American Seafoods Group LLC - Head Office
Marel ehf - Group Headquarters
SalMar ASA - Group Headquarters
Sajo Industries Co., Ltd
Hansung Enterprise Co.,Ltd.
BIM - Irish Sea Fisheries Board (An Bord Iascaigh Mhara)
CEFAS - Centre for Environment, Fisheries & Aquaculture Science
COPEINCA ASA - Corporacion Pesquera Inca S.A.C.
Chun Cheng Fishery Enterprise Pte Ltd.
Food Project (Siam) Co., Ltd.
VASEP - Vietnam Association of Seafood Exporters & Producers
Gomes da Costa
Furuno Electric Co., Ltd. (Headquarters)
NISSUI - Nippon Suisan Kaisha, Ltd. - Group Headquarters
FAO -Food and Agriculture Organization- Fisheries and Aquaculture Department (Headquarter)
Hagoromo Foods Co., Ltd.
Koden Electronics Co., Ltd. (Headquarters)
A.P. Møller - Maersk A/S - Headquarters
BVQI - Bureau Veritas Quality International (Head Office)
UPS - United Parcel Service, Inc. - Headquarters
Hamburg Süd Group - (Headquearters)
Armadora Pereira S.A. - Group Headquarters
NOAA - National Oceanic and Atmospheric Administration (Headquarters)
Omega Protein Corporation -Headquarter-
Marona S.A.
Marine Harvest ASA - Headquarters
Marubeni Europe Plc -UK-
Findus Ltd
Icom Inc. (Headquarter)
WWF Centroamerica
Oceana Group Limited
The David and Lucile Packard Foundation
Ajinomoto Co., Inc. -Headquarter-
Friosur S.A. - Headquarters
Cargill, Incorporated - Global Headquarters
Benihana Inc.
Leardini Pescados Ltda
Mitsubishi Corporation Marine Products Depts. D.Team
CJ Corporation  -Holding Headquarter-
Greenpeace International - The Netherlands
David Suzuki Foundation
Fisheries and Oceans Canada -Communications Branch-
Mitsui & Co.,Ltd - Headquarters
Ocean Trawlers Group - Ocean Trawlers HK Ltd.
Natori Co., Ltd.
Carrefour Supermarket - Headquarters
FedEx Corporation -Headquarter-
AKBM - Aker BioMarine ASA
Seafood Choices Alliance -Headquarter-
Austevoll Seafood ASA
Walmart / Wal-Mart Stores, Inc. (Supermarket) -Headquarter-
New Japan Radio Co.Ltd (JRC) -Head Office-
Gulfstream JSC
INVE Group - Head Office
Marine Stewardship Council - MSC Worldwide Headquarters
Royal Dutch Shell plc (Headquarter)
Genki Sushi Co.,Ltd -Headquarter-
Iceland Pelagic ehf
AXA Assistance Argentina S.A.
Caterpillar Inc. - Headquarters
Tiger Brands Limited
Morpol ASA - Group Headquarters
SeaChoice
National Geographic Society
AmazonFresh, LLC - AmazonFresh

Copyright 1995 - 2015 Fish Info & Services Co.Ltd| All Rights Reserved.   DISCLAIMER