Mass spawning

Under certain conditions, ovulation and plasma gonadotropin levels can be stimulated by ovarian fluid from other ovulated females. The African catfish, Clariasgaricpinus, is an example. It lives in muddy water and spawns at night, conditions expected to favor pheromone commimication. Moreover, this species is a seasonal breeder, spawning after rainfall. The sudden mass spawning requires synchronization. Water from males or ovulated females, and also ovarian fluid of ovulated females, experimentally induced ovulation in 67% of females. Plasma gonadotropin was also increased by these treatments (Resink etal., 1989c). 

Wdd, C., ToUrian, R., Huettel, M. (2004c). Rapid recycling of coral mass-spawning products in permeable reef sediments. Marine Ecology Progress Series 271, 159—166. 

Artificial fertilisation is systematically used on salmonids genetic improvement programs, even if some also rely on mass spawning. Instead, the latter technique is the most popular for species characterised by difficulties in fully mastering the artificial fertilisation like the Atlantic cod, the European seabass, the gilthead seabream and the common sole. 

OLAVIDES R D D, RODRIGUEZ B D R and JUiNio-MENEZ M A (2011) Simultaneous mass spawning of Holothuria scabra in sea ranching sites in Bohnao and Anda munici-pahties, Philippines. SPC Beche-de-mer Information Bulletin, 31, 23-24. 

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