NEXT PAGE t:> the fishery. These parents must mature, spawn, and fertilize eggs which hatch to larvae, only a very small fraction of whIch eventually survive and become fully formed young fish (recruits). Generally the females of most fish species produce several thousands of eggs, sometimes even several millions as in the case of some commercially exploited species in temperate waters. To a ce...

Proximate analysis of broodstock and grow-out feeds for gamitana (Colossoma macropomum) and paco (Piaractus brachypomus) and their constituent feedstuffs was conducted. Literature values for specific nutrients known to affect fish reproduction were calculated from published sources for the broodstock diet. Fatty acid and amino acid profiles of broodstock eggs were obtained. Analytical informati...

The gonadsomatic index (GSI) of mottled skate was the highest in April, GSI and HSI showed a reverse phase for its reproductive cycle. The fish had one pair of egg capsules, having 1 to 7 fertilized eggs, and spawned all the year round. When surveying the reproductive characteristics of females over 63 ㎝ in disc width, we found the spawning peak was between April to June, and the appearance rat...

Although fertilization was observed by Fol more than 100 years ago, mechanisms for effecting a block to polyspermy in fish are largely unknown. In this review, the recent studies of polyspermy block mechanisms in teleost fish eggs will be presented, including morphological, biochemical, and molecular results.

—Praziquantel, an anthelmintic, is commonly used to control the Asian fish tapeworm Bothriocephalus acheilognathi in grass carp Ctenopharyngodon idella and baitfish. We treated 50 individuals from three different cyprinid fish species with praziquantel at 6 mg/L, a dose higher than the minimum recommended for complete Asian tapeworm removal in 24 h but much less than the concentration that woul...

The gene for vitellogenin, an egg yolk protein precursor, is usually silent in male fish but can be induced by estrogen exposure. For this reason, vitellogenin production in male fish has become a widely used indicator of exposure to exogenous estrogens or estrogen mimics in the aquatic environment. The utility of this indicator to predict impacts on fish reproductive success is unclear because...

The induction of synthesis of the "female" yolk precursor protein vitellogenin (VTG) in male fish by estrogenic chemicals in the environment has been demonstrated in many recent reports. However, little is known about the organismal and biological significance of this phenomenon. To examine the relationship between VTG production in male fish and reproductive impairment, adult male medaka were ...

We investigated occurrence, transport pathways, and effects of polybrominated diphenyl ether (PBDE) flame retardants and other endocrine disrupting chemicals (EDCs) in aquatic media and the foodweb in the lower Columbia River. In 2009 and 2010, foodweb sampling at three sites along a gradient of contaminant exposure near Skamania (Washington), Columbia City (Oregon) and Longview (Washington) in...

BACKGROUND Processed meat and fish have been shown to be associated with the risk of advanced prostate cancer, but few studies have examined diet after prostate cancer diagnosis and risk of its progression. OBJECTIVE We examined the association between postdiagnostic consumption of processed and unprocessed red meat, fish, poultry, and eggs and the risk of prostate cancer recurrence or progre...

OBJECTIVES This study compares the adherence of immigrant and Spanish adolescents residing in the Madrid region (Spain) to national dietary recommendations. The factors compared were the consumption of items from the eight basic food groups (vegetables, fruits, bread/cereals, meat, eggs, fish, legumes and milk/dairy products), including the excessive or deficient consumption of eggs, meat and f...