title: Chronic effects of light irradiated from LED on the growth performance and endocrine properties of barfin flounder Verasper moseri.
abstract: We investigated the effects of specific wavelengths of light on the growth of barfin flounder. The fish, reared in white tanks in a dark room, were irradiated with light from light-emitting diodes (LEDs) with peak wavelengths of 464nm (blue), 518nm (green), and 635nm (red) under a controlled photoperiod (10.5:13.5, light-dark cycle; 06:00-16:30, light). Fish were reared for four weeks in three independent experiments at three different water temperatures (averages of 14.9°C, 8.6°C, and 6.6°C). The fish irradiated with blue and green light had higher specific growth rates (% body weight⋅day(-1)) than fish irradiated with red light. Notably, green light had the greatest effect on growth among the three light wavelengths at 6.6°C. In the brains of fish reared at 6.6°C, the amounts of melanin-concentrating hormone 1 mRNA under green light were lower than those under red light, and amounts of proopiomelanocortin-C mRNA under blue and green light were higher than those under red light. No differences were observed for other neuropeptides tested. In the pituitary, no difference was observed in growth hormone mRNA content. In plasma, higher levels of insulin and insulin-like growth factor-I were observed in fish under green light than those of fish under red light. These results suggest that the endocrine systems of barfin flounder are modulated by a specific wavelength of light that stimulates somatic growth.
authors.affiliation: School of Marine Biosciences, Kitasato University, Kanagawa 252-0373, Japan. Electronic address: akiyoshi@kitasato-u.ac.jp.
authors.forename: Akiyoshi
authors.initials: A
authors.lastname: Takahashi
authors.affiliation: School of Marine Biosciences, Kitasato University, Kanagawa 252-0373, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kasagi
authors.affiliation: Hokkaido National Fisheries Research Institute, Fisheries Research Agency, Hokkaido 088-1108, Japan.
authors.forename: Naoto
authors.initials: N
authors.lastname: Murakami
authors.affiliation: Stanley Electric Co., Ltd., Tokyo 153-8636, Japan.
authors.forename: Sumihisa
authors.initials: S
authors.lastname: Furufuji
authors.affiliation: K·M Act Co., Ltd., Iwate 021-0852, Japan.
authors.forename: Shigeto
authors.initials: S
authors.lastname: Kikuchi
authors.affiliation: School of Marine Biosciences, Kitasato University, Kanagawa 252-0373, Japan.
authors.forename: Kanta
authors.initials: K
authors.lastname: Mizusawa
authors.affiliation: Seikai National Fisheries Research Institute, Fisheries Research Agency, Nagasaki 851-2213, Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Andoh
mesh_terms: D000818:Animals; D005399:Fishes / Q000254:growth & development* / Q000378:metabolism; D005432:Flounder / Q000254:growth & development* / Q000378:metabolism; D007028:Hypothalamic Hormones / Q000235:genetics*; D008027:Light / Q000009:adverse effects*; D008543:Melanins / Q000235:genetics*; D010907:Pituitary Hormones / Q000235:genetics*
chemical_list: D007028:Hypothalamic Hormones; D008543:Melanins; D010907:Pituitary Hormones; C019463:melanin-concentrating hormone
keywords: Barfin flounder; Green light; Growth performance; Light-emitting diodes; Specific wavelength; Temperature