Irradiation of rainbow trout at early life stages results in a proteomic legacy in adult gills. Part A; proteomic responses in the irradiated fish and in non-irradiated bystander fish.

Exposure to a single 0.5 Gy X-ray dose of eggs at 48 h after fertilisation (48 h egg), eyed eggs, yolk sac larvae (YSL) and first feeders induces a legacy effect in adult rainbow trout. This includes the transmission of a bystander effect to non-irradiated adult trout which had swam with the irradiated fish.

Irradiation of rainbow trout at early life stages results in a proteomic legacy in adult gills. Part B; the effect of a second radiation dose, after one year, on the proteomic responses in the irradiated and non-irradiated bystander fish.

This study extends the investigation of the legacy effects of exposure to a single radiation dose at one of four early life stages, in adult rainbow trout (Part A), by examining the effects of a second identical dose after one year; i.e. egg 48 h after fertilisation (48 h egg) + 1 year, eyed egg + 1 year, yolk sac larvae (YSL) + 1 year and first feeder + 1 year.

Irradiation of rainbow trout at early life stages results in trans-generational effects including the induction of a bystander effect in non-irradiated fish.

The bystander effect, a non-targeted effect (NTE) of radiation, which describes the response by non-irradiated organisms to signals emitted by irradiated organisms, has been documented in a number of fish species. However transgenerational effects of radiation (including NTE) have yet to be studied in fish. Therefore rainbow trout, which were irradiated as eggs at 48h after fertilisation, eyed eggs, yolk sac larvae or first feeders, were bred to generate a F1 generation and these F1 fish were bred to generate a F2 generation.

Exposure to acute levels of waterborne aluminium modifies the legacy of early life stage irradiation, including the communication of radiation-induced bystander signals, in adult rainbow trout.

Purpose: To determine if the legacy of early life stage irradiation seen in rainbow trout is modified in adult fish by acute exposure to waterborne aluminium (Al).

Methods: Two-year-old trout which had been irradiated as either eggs 48 h after fertilization, eyed eggs, yolk sac larvae or as first feeders, were exposed to 100 or 200 μg l(-1) Al. These fish were then paired with untreated fish.

Tissue-specific effects of acute aluminium exposure on the radiation-induced bystander effect in rainbow trout (Oncorhynchus mykiss, Walbaum).

Purpose: To investigate if aluminium (Al) modifies the rainbow trout response to radiation exposure and/or the induction of a radiation-induced bystander effect.

Methods: Rainbow trout were exposed to 100 or 200 μg l(-1) Al (for 3 h), a 0.5 Gy X-ray dose or Al followed immediately by irradiation.

The induction of a radiation-induced bystander effect in fish transcends taxonomic group and trophic level.

Purpose: To extend the investigations of bystander effect induction in fish of the same species as the irradiated fish, to bystander effect induction between fish species and between trophic levels.

Materials And Methods: To investigate interspecies bystander effect induction, zebrafish and medaka were irradiated with a 0.5 Gy X-ray dose and then swum with non-irradiated fish of the same and opposite species.

Investigating fear in rainbow trout (Oncorhynchus mykiss) using the conditioned-suppression paradigm.

Trout learned the operant task of pendulum-pressing for a food-reward in a mean of 4.3 sessions lasting 1 hr. In a separate phase, fish also learned--through classical conditioning--to associate a neutral light cue with an aversive stimulus.

Estimating aquatic phosphorus concentrations 30 metres down-current from a rainbow trout cage array.

Aquatic total phosphorus (Tot-P) is measured 30 m distant from rainbow trout (Oncorhynchus mykiss) cages, for regulatory compliance on the Canadian side of Lake Huron. The ability to predict changes in near-field Tot-P concentrations from changes in production, or to explain near-field concentrations in the event of compromised reference sites, would be very useful for managers and farmers. A logical first step in the development of a near-field model is the estimation of down-current Tot-P concentrations.

Repeated low-level exposure of the round goby (Neogobius melanostomas) to Clostridium botulinum type E neurotoxin.

In a 4-mo study (June 2004-September 2004), round gobies (Neogobius melanostomas) were dosed orally every 72 hr for up to 21 days with Clostridium botulinum neurotoxin type E (BoNT/E) at one of four doses: 0, 50, 250, and 500 mouse lethal doses (MLD). Fish were observed for changes in pigmentation and behavior for the duration of the experiment. Mortality was observed with all treatments, with the exception of the 0 MLD control.

Toxicity of Clostridium botulinum type E neurotoxin to Great Lakes fish: implications for avian botulism.

Since 1999, large-scale mortalities of fish-eating birds have been observed on the Great Lakes, and more specifically on Lake Erie. Type E botulism has been established as the primary cause of death. The mechanism of type E botulism exposure in fish-eating birds is unclear.

Near-field loading dynamics of total phosphorus and short-term water quality variations at a rainbow trout cage farm in Lake Huron.

Aquatic total phosphorus (Tot-P) is measured at fish-cages in Lake Huron for environmental regulatory compliance. An improved understanding of how Tot-P is manifested in the near-field ( View Article and Find Full Text PDF

Persistence of Clostridium botulinum neurotoxin type E in tissues from selected freshwater fish species: implications to public health.

Rainbow trout (Oncorhynchus mykiss), round gobies (Neogobius melanostomas), yellow walleye (Stizostedion vitreum), and yellow perch (Perca flavescens) were given Clostridium botulinum neurotoxin type E (BoNT/E) at four doses (0, 800, 1500, and 4000 mouse lethal doses). BoNT/E was sought in the fish tissues at death or at the conclusion of the experiment (10 days after treatment). Fish were divided into a "fillet" (axial musculature) and a "nonfillet" sample before testing for BoNT/E toxicity with a mouse bioassay.