First substantiated record of the black-striped pipefish, Syngnathus abaster (Actinopterygii: Syngnathiformes: Syngnathidae), in the freshwaters of Bosnia and Herzegovina

Although the ichthyofauna of Bosnia and Herzegovina has been relatively well studied, the knowledge remains incomplete. This report confirms the occurrence of the black-striped pipefish Syngnathus abaster Risso, 1827 in the freshwaters of Bosnia and Herzegovina. A sample specimen of the black-striped pipefish was obtained from the Neretva River in Bosnia and Herzegovina in July 2011. The morphometric measurements and meristic counts were taken. Although the black-striped pipefish has previously been reported to exist in this region, the data were not reliable or conclusive. Therefore the finding reported herewith can be considered the first substantiated record from Bosnia and Herzegovina and extends the previously known distribution range for this species into freshwaters

Comparative gonadogenesis and hormonal induction of spawning of cultured and wild mediterranean amberjack (Seriola dumerili, Risso 1810)

The histological characteristics of wild and cultured Mediterranean amberjack gonads were studied during the first four years of their life cycle. No differences were found in the gonad development of both wild and captive males and females during the first and second year. In the third year, wild females showed more advanced oocyte development than captive females. In the fourth year, vitellogenic oocytes were noted for captive females. Fertilised eggs were obtained after a HCG hormone treatment of four- to nine-year old wild specimens. A smaller quantity of mature and fertilised eggs was also obtained through the spawning of hormone-treated four-year old captive broodstock specimens. Eggs in the stage of gastrulation died within eight hours following fertilisation.No disponibl

Sustainable large‐scale production of European flat oyster ( Ostrea edulis ) seed for ecological restoration and aquaculture: a review

The conservation and active restoration of European flat oyster (Ostrea edulis) populations are a major focus of ecological restoration efforts to take advantage of the wide‐ranging ecosystem functions and services this species provides. Accordingly, additional and new demands for seed oysters have arisen. In commercial aquaculture (mariculture), the production of O. edulis is still largely based on natural seed collection. Considering the specific requirements, related to ecological restoration, such as the absence of pathogens and the preservation of high genetic diversity, the current supply is insufficient. Despite the development of breeding and controlled reproduction techniques for this species since the late 1930s, seed production today is mainly based on empirical concepts. Several of the issues that producers still face are already subjects of research; many others are still unanswered or even unaddressed. This review provides a summary of all available knowledge and technologies of O. edulis seed production. Furthermore, it provides a detailed reflection on implications for restoration, future challenges, open questions and it identifies relevant research topics for sustainable seed supply. The study covers the following aspects on (i) biology of the species, (ii) stressors – including pathogens and pollutants, (iii) genetics, (iv) history of production technologies, (v) seed production in polls, (vi) seed production in ponds and (vii) seed production in hatcheries. Future research needs on sex determinism, gametogenesis, cryopreservation, nutrition, selective breeding, pathogens and disease, and the development of reliable protocols for production are highlighted