Determination of the spawning history of Pacific saury Cololabis saira from rearing experiments: identification of post-spawning fish from histological observations of ovarian arterioles

作者：Suyama Satoshi^*; Shimizu Akio; Isu Sayoko; Ozawa Hitomi; Morioka Taizo; Nakaya Mitsuhiro; Nakagawa Toru; Murakami Naoto; Ichikawa Takashi; Ueno Yasuhiro

来源：Fisheries Science, 2016, 82(3): 445-457.

DOI：10.1007/s12562-016-0980-1

• Pacific saury
• Rearing experiments
• Atresia
• Maturational stages
• Post-spawning fish
• Arterioles in the ovaries

Rearing experiments under controlled temperature conditions were carried out to establish a methodology for estimating the spawning history of the Pacific saury Cololabis saira. The experiments involved histological examination of ovarian arterioles at various maturational stages. We found that pre-spawning immature fish lacked Victoria blue (VB)-positive arterioles in the ovaries, as did maturing fish, while post-spawning females had VB-positive arterioles. The latter were also observed after 6 months when most spawning activity had ceased. The results indicate that VB-positive ovarian arterioles are a characteristic feature of actively spawning Pacific saury and that females with VB-positive arterioles can be classified as post-spawning fish. Females without VB-positive arterioles can be regarded as "practically unspawned" fish, and this group may include some fish that have spawned a number of times, in addition to completely unspawned fish. The methodology has many practical uses such as in the estimation of maturation rates for stock management.

• 出版日期2016-5