In a survey of Vibrio concentrations in white shrimp postlarvae at two inland farms, hatchery postlarvae were acclimated in water with salinity reduced from 30 and 5 ppt to 2 ppt at the farms. One farm stocked postlarvae in nursery ponds, and the other stocked directly into grow-out ponds.
Polymerase chain reaction testing is a powerful tool that can detect very low levels of pathogens, but its ability to screen and produce results that represent the population is often oversimplified. Screening of the wrong tissues or too few animals can lead to incorrect conclusions.
The Oceanic Institute of Hawaii Pacific University has been working to develop methods to culture yellow tang, a top species collected for the aquarium trade. The fish under culture are living longer as practices improve.
Honduras-based Grupo Granjas Marinas believes that large-scale production of rotifers and copepods and sequential pond inoculations, in combination with short shrimp growth cycles can significantly increase shrimp production while reducing dependency on other sources of protein in feeds.
Recent research by the authors discovered genetic markers for the identification of Pacific white shrimp with enhanced capability to convert soy protein in feed.
Seaweed aquaculture represents approximately half of the world mariculture production, but since seaweed farming is mostly concentrated in Asian countries, there is a lack of appreciation for this resource in the Western world.
In early 2014, a trial to evaluate the effects of a mixture of Bacillus strains on early mortality syndrome bacteria during the larviculture and nursery phases for shrimp was carried out at a commercial hatchery in Mexico.
Work by the authors analyzed price competition for farmed sea bream from Greece, Turkey and Spain across the value chain.
Disease problems on shrimp farms may be partly driven by an interaction between management practices that cause inbreeding in small hatcheries and the amplification by inbreeding of susceptibility to disease and environmental stresses.
There is a clear difference between the shrimp postlarvae traits that are economically important in Central and South America versus those of Asia, creating a challenge for breeders to satisfy the somewhat opposing breeding goals the regions demand.
Although the characteristics of shrimp postlarvae have changed over time, the standard method used to identify their size has not. Usually, the “size” of postlarvae is considered their chronological age after completing metamorphosis.
In a study, “pre-fertilization” in the nursery phase of a biofloc system for shrimp was tested. The objective was to accelerate the biofloc formation to minimize ammonia concentrations, avoiding high peaks during culture.
By dividing ponds into smaller, more controllable areas, IPRS can substantially reduce chemical treatment costs, improve treatment delivery and allow new treatments that are cost-prohibitive in traditional pond settings.
Cathepsin D alone and in combination with other cathepsins presents the greatest proteolytic activity on some fish muscles.
Cathepsins B, D and L are considered critical in fish muscle post-mortem modifications or gel softening during the setting of surimi.
A growth trial in Canada evaluated the use of algae biomass to increase the concentration of long-chain polyunsaturated fatty acids in the tissues of rainbow trout.