W hen females are sexually promiscuous, the ejaculates of different males may compete for the fertilization of a set of ova, a process known as sperm competition. In internally fertilizing species, potential for sperm competition occurs whenever the ejaculates of different males cooccur in the female reproductive tract at the time of ovulation. Sperm competition is now recognized as a powerful ...

The antifertility effects of Abrus precatorius root bark meal (APRB) on Coptodon zillii juvenile was determined by a 42 days feeding experiment, with the inclusion levels 0g, 6g, 12g, 18g and 24g/kg diet. Water volume 20 litres in plastic tank (50cm x 27cm 35 cm dimension) maintained throughout period experiment. fed at 4% body weight. In male fish, testis weight, milt volume, count motility du...

cobitis sp. is an endemic spined loach species from the dough river in the southern caspian sea basin, (golestan province, iran). to provide some reproductive features of this fish, sampling was performed at monthly intervals throughout the year and 417 individuals were collected. the specimens ranged in total length from 27.1 to 92.9 mm and total weight from 0.11 to 6.79 g. the spawning of spi...

The Arabian carpet shark, Chiloscyllium arabicum is endemic to the Gulf and northern Sea. aim of this work study reproduction maturity species. A total 87 males 139 females, including 19 egg-bearing individuals collected from bottom set longline fisheries in Saudi waters between October 2017 February 2019, were examined. size at 50% was estimated as 62.3 62.5 cm length (TL) for respectively. Ch...

In the present study, various developmental stages of Liza aurata oocyte, especially IV and V stages have been described. On the basis of histological investigations, oocyte development in L. aurata comprises immature (I), the early maturing (II), the late maturing (III), mature (IV), ripe (V), and spent (VI) stages. In the stages I and II, nucleus occupied large volume of oocyte. Vacuolization...

Some reproduction characteristics of keeled mullet, Liza klunzingeri, were studied during Apr. 2003 to Feb. 2004 in Khuzestan waters of the Persian Gulf. A total of 836 samples were monthly collected from two fish landings of Bahrekan and Hendijan; 727 specimens were studied from point of sex determination, and 60 specimens were studied from the fecundity point of view. This species was found t...

Some reproduction characteristics of the Caspian Vimba, Vimba vimba persa, were studied from Oct. 2008 to Sep. 2009 in coastal waters of the Caspian Sea (Mazandaran province). 994 specimens were monthly collected from 6 fish landing sites of Ramsar, Tonekabon, Chalus, Mahmood Abad, Sari and Behshahr. The fecundity was measured using 92 specimens. This species was found to have more abundance in...

Studies that aim to characterise the susceptibility of ecologically relevant and non-model fish polar cod (Boreogadus saida) model carcinogens are required. Polar were exposed under laboratory conditions for six months control, 0.03 μg BaP/g fish/week 0.3 dietary benzo(a)pyrene (BaP), a reference carcinogen. The concentrations 3-OH-BaP bile metabolite transcriptional responses genes involved in...

The present study aimed to investigate the reproductive biology of Labeobarbus altianalis from River Kuja-Migori basin, Kenya. This fish species is distributed in most water bodies Lake Victoria basin and effluent rivers. susceptible fishing due aggregation at river mouths during reproduction seasons. We conducted a for 18 months with an objective determining length 50% sexual maturity, fecundi...