The mechanism of reproduction and hormonal function in finfish species: A review

Abstract

The number of aquatic species currently under domestication efforts is rising rapidly, due to the development of commercial aquaculture. For domestication and the establishment of a sustainable aquaculture industry, the control reproduction processes of fish in captivity, and to acquire high quality seed, is necessary. The fish reproductive cycle is separated in gametogenesis (of growth) and oocyte maturation and spermiation (of maturation). These are controled by the reproductive hormones of the brain, pituitary and gonad. Environmental and endogenous physiological information reach neuroendocrine system that regulates pituitary and gonadal functions. The most commonly reproduction dysfunctions in cultured fish are the unpredictability of final oocyte maturation (FOM) in females, and the lack and less quality of sperm in males. These problems are due to the fact that the fish in captivity does not have the same conditions in the spawning grounds, and as a result, there is a failure of the proper hormonal regulation. Failure of the pituitary to release gonadotropin (GTH-II), one of the hormones involved in the regulation of reproduction, is the result of unsucssesful ovulation. Actually two type of GTH are identified. They are differing from structural and chemical roles. GTH-I also name as FSH, involve in vitellogenesis or spermatogenesis (initial stage of gametogenesis), and GTH-II name as LH are involve in FOM and spermiogenesis and spermiation.The control role and function of the hormone involve in reproduction are described and reviewed in the present paper.

Fatty acid and proximate composition of wild male and female king angelfish (Holacanthus passer) gonads during the ripe and spent developmental stages

“…Additionally, it is well known that the reproduction of marine finfish under controlled conditions also reduces the impact of heavy fishing pressure on wild populations (Mehdi and Ehsan, 2011;Arantes et al, 2012), but successful reproduction in captivity requires the knowledge of several aspects of the adult life stage of an organism (Izquierdo et al, 2001;Olivotto et al, 2011). For H. passer, Arellano-Martínez et al (1999) established that it is a partial spawner with asynchronous development of the gonads; its reproductive cycle is dictated by five phases of gonadal development, with sexual maturity and reproductive activity attained during the period of April to November.…”

Hormonal induction maturation of silver pompano Trachinotus blochii

“…The activity of hCG hormone is more similar to LH and less similar to FSH. hCG hormone induced the gonadotropin concentration during the vitellogenesis process and final maturation (Mehdi & Ehsan, 2011). PG600 hormone was a combination of PMSG and hCG, therefore having more composition and concentration of FSH and LH, which worked more than PMSG and hCG, affecting a faster gonad development, as well as higher GSI and HSI value.…”

“…The vitellogenin synthesis is influenced by 17β-estradiol as vitellogenin and andrgens biosynthesis stimulator presented in fish body. This happens as androgens will converted into estrogens by liver aromatase (Elakkanai et al, 2017) and suspected phytoestrogens supplemented in fish feed such as soy beans and alfalfa plant have a positive influence on the fish vitellogenesis (Mehdi et al, 2011;Yaron & Levavi, 2011). According to Yaron andLevavi (2011), andEkokotu andOlele (2014), when the vitellogenesis process occurs, the egg yolk granules or globules increase in number and size, resulting an enlarged oocyte volume.…”

Pengaruh Penyuntikan Hormon Ovaprim Terhadap Kinerja Pemijahan Ikan Tengadak (Barbonymus Schwanenfeldii)

“…Selain itu, adanya antidopamin akan menghambat aktivitas dopamine, sehingga meningkatkan kinerja kelenjar hipotalamus dalam merilis GnRH. Menurut Nagahama (1994), Yaron et al (2003) dan Mehdi & Mousavi (2011), hormon GnRH yang terdapat pada plasma akan mempengaruhi hipofisa dalam meningkatkan pelepasan gonadaotropin hormone (GtH). GtH yang telah dirilis oleh hipofisa selanjutnya berkerja pada organ target sehigga merangsang perkembangan telur atau pematangan akhir.…”

“…NO .2. TH 2017FPIK UNMUH-PNK ISSN 2541 break down (GVBD) biasanya terjadi karena adanya rangsangan steroid (Nagahama, 1994;Mehdi & Mousavi, 2011).…”