With the current trends in climate and fisheries, well-designed mitigative strategies for conserving fish stocks may become increasingly necessary. The poor post-release survival of hatchery-reared Pacific salmon indicates that salmon enhancement programs require assessment. The objective of this study was to determine the relative roles that genotype and rearing environment play in the phenoty...

Veterinary control and routine sanitary procedures in commercial poultry hatcheries should include the following: choice of a suitable geographical location to ensure an isolated site; proper hatchery design with separation of major operations; one-way flow of work within the hatchery; adequate ventilation of each room; routine cleaning and disinfection; formaldehyde fumigation or alternative m...

—If hatchery-reared salmon delay emigration after release, they may compete with wild salmon in freshwater rearing habitat. We measured the densities and size distributions of ocean-type juvenile Chinook salmon Oncorhynchus tshawytscha in two rearing areas downstream of a hatchery in the Sacramento River, California, before, during, and after two large releases in both 2001 and 2002. Densities ...

TWO STRATEGIES HAVE BEEN PROPOSED TO AVOID NEGATIVE GENETIC EFFECTS OF ARTIFICIALLY PROPAGATED INDIVIDUALS ON WILD POPULATIONS: (i) integration of wild and captive populations to minimize domestication selection and (ii) segregation of released individuals from the wild population to minimize interbreeding. We tested the efficacy of the strategy of segregation by divergent life history in a ste...

Pacific threadfin, Polydactylus sexfilis, is popular fish in recreational fishing, as well as aquaculture in Hawaii. Its natural population has been continuously declining in the past several decades. Microsatellite DNA markers are useful DNA-based tool for monitoring Pacific threadfin populations. In this study, fifteen Microsatellite (MS) DNA markers were identified from a partial genomic Pac...

The release of hatchery-reared fishes for restoring threatened and endangered populations is one of the most controversial issues in applied ecology. A central issue has been to determine whether releases cause extinction of local wild populations. This may arise either through domesticated or non-local fishes hybridizing with wild fishes, or through inappropriate behavioural interactions; for ...

The extent to which stray, hatchery-reared salmon affect wild populations is much debated. Although experiments show that artificial breeding and culture influence the genetics of hatchery salmon, little is known about the interaction between hatchery and wild salmon in a natural setting. Here, we estimated historical and contemporary genetic population structures of chum salmon (Oncorhynchus k...

Salmon produced by hatcheries have lower fitness in the wild than naturally produced salmon, but the factors underlying this difference remain an active area of research. We used genetic parentage analysis of alevins produced by experimentally mixed groups of wild and hatchery coho salmon (Oncorhynchus kisutch) to quantify male paternity in spawning hierarchies. We identify factors influencing ...

Naïve, hatchery-reared Atlantic salmon Salmo salar parr were paired with demonstrators that had been pre-trained to accept live prey from the surface or from the benthos. After 6 days of observing demonstrators through a clear perspex partition the naïve fish’s benthic foraging skills were tested. The results revealed that hatchery-reared Atlantic salmon can be taught to target benthic prey ite...

the purpose of this study was to evaluate the profitability of hatchery litter recycling into poultry feedstuff supplement. the data were collected in 2011 in 4 provinces, by direct interviewing of all hatcheries which used the hatchery litter drying machine. net present value (npv), benefit-cost ratio (bcr), and internal rate of return (irr) methods were applied for this analysis. in the studi...