Magnetoreception in fishes: the effect of magnetic pulses on orientation of juvenile Pacific salmon.

A variety of animals sense Earth's magnetic field and use it to guide movements over a wide range of spatial scales. Little is known, however, about the mechanisms that underlie magnetic field detection. Among teleost fish, growing evidence suggests that crystals of the mineral magnetite provide the physical basis of the magnetic sense.

Rearing environment affects spatial learning in juvenile Chinook salmon Oncorhynchus tshawytscha.

We tested the prediction that a complex physical rearing environment would enhance short-term spatial memory as assessed by learning ability in a spatial navigation task in juvenile Chinook salmon Oncorhynchus tshawytscha. We reared fish in two low-density treatments, where fish were either in bare fiberglass tanks (bare) or in tanks with physical structure (complex). We also tested conventionally reared high-density hatchery fish to compare with these other experimental treatments.

Magnetic map in nonanadromous Atlantic salmon.

Long-distance migrants, including Pacific salmon ( spp), can use geomagnetic information to navigate. We tested the hypothesis that a "magnetic map" (i.e.

Egg size and growth in steelhead Oncorhynchus mykiss.

The effects of egg size on early development and growth of steelhead Oncorhynchus mykiss were recorded for more than 200 days following hatching. Fish from smaller eggs hatched sooner and at a smaller size than fish from larger eggs, but fish from smaller eggs showed consistently higher growth rates than fish from larger eggs. Since many life-history attributes appear to be determined by size or growth rate at age during the first year, egg size could be a significant predictor of important changes in the life history of individuals.

The effect of rearing structures on behaviour and movement of juvenile steelhead Oncorhynchus mykiss.

The relative movement of juvenile steelhead Oncorhynchus mykiss reared on two treatments was investigated to provide insight on the effect of structure in the rearing environment on the behaviour of the fish before potential release into a natural river system. The progeny of wild broodstock were reared either in the presence or absence of structure in the tank environment for 7 months at the Oregon Hatchery Research Center located in Oregon, U.S.

Geomagnetic field influences upward movement of young Chinook salmon emerging from nests.

Organisms use a variety of environmental cues to orient their movements in three-dimensional space. Here, we show that the upward movement of young Chinook salmon () emerging from gravel nests is influenced by the geomagnetic field. Fish in the ambient geomagnetic field travelled farther upwards through substrate than did fish tested in a field with the vertical component inverted.

Michael Pittaway.

A widely respected veterinary surgeon and an innovator within the profession, Michael Pittaway was also a man of great charm and huge energy, who applied his skills across a wide range of interests.

Egg size and emergence timing affect morphology and behavior in juvenile Chinook Salmon, .

Variation in early life history traits often leads to differentially expressed morphological and behavioral phenotypes. We investigated whether variation in egg size and emergence timing influence subsequent morphology associated with migration timing in juvenile spring Chinook Salmon, . Based on evidence for a positive relationship between growth rate and migration timing, we predicted that fish from small eggs and fish that emerged earlier would have similar morphology to fall migrants, while fish from large eggs and individuals that emerged later would be more similar to older spring yearling migrants.

Multispectral imaging of organ viability during uterine transplantation surgery in rabbits and sheep.

Uterine transplantation surgery (UTx) has been proposed as a treatment for permanent absolute uterine factor infertility (AUFI) in the case of the congenital absence or surgical removal of the uterus. Successful surgical attachment of the organ and its associated vasculature is essential for the organ’s reperfusion and long-term viability. Spectral imaging techniques have demonstrated the potential for the measurement of hemodynamics in medical applications.

Salinity effects on plasma ion levels, cortisol, and osmolality in Chinook salmon following lethal sampling.

Studies on hydromineral balance in fishes frequently employ measurements of electrolytes following euthanasia. We tested the effects of fresh- or salt-water euthanasia baths of tricaine mesylate (MS-222) on plasma magnesium (Mg(2+)) and sodium (Na(+)) ions, cortisol and osmolality in fish exposed to saltwater challenges, and the ion and steroid hormone fluctuations over time following euthanasia in juvenile spring Chinook salmon (Oncorhynchus tshawytscha). Salinity of the euthanasia bath affected plasma Mg(2+) and Na(+) concentrations as well as osmolality, with higher concentrations in fish euthanized in saltwater.

Patterns of variation and covariation in the shapes of mandibular bones of juvenile salmonids in the genus Oncorhynchus.

What is the nature of evolutionary divergence of the jaw skeleton within the genus Oncorhynchus? How can two associated bones evolve new shapes and still maintain functional integration? Here, we introduce and test a "concordance" hypothesis, in which an extraordinary matching of the evolutionary shape changes of the dentary and angular articular serves to preserve their fitting together. To test this hypothesis, we examined morphologies of the dentary and angular articular at parr (juvenile) stage, and at three levels of biological organization—between salmon and trout, between sister species within both salmon and trout, and among three types differing in life histories within one species, Oncorhynchus mykiss. The comparisons show bone shape divergences among the groups at each level; morphological divergence between salmon and trout is marked even at this relatively early life history stage.

Achieving an early pregnancy following allogeneic uterine transplantation in a rabbit model.

Objective: Uterine transplantation (UTx) has been proposed as a treatment option for women diagnosed with absolute uterine factor infertility (AUFI). The goal of UTx remains achieving pregnancy and live birth of a healthy neonate following allogeneic UTx. Our aim was to assess whether fertility was possible following allogeneic uterine transplantation (UTx), when the recipient had demonstrated long-term survival and had been administered immunosuppression.

Achieving uterine auto-transplantation in a sheep model using iliac vessel anastomosis: a short-term viability study.

Objective: To investigate, develop and evaluate anatomical, surgical and anastomotic aspects necessary for a successful uterine transplant in a large-animal model.

Design: Sheep model; longitudinal study involving five ewes.

Setting: Royal Veterinary College, London, UK.

Uterine allotransplantation in a rabbit model using aorto-caval anastomosis: a long-term viability study.

Objective: Uterine transplantation (UTx) has been proposed as a treatment option for women diagnosed with absolute uterine factor infertility. Allogeneic UTx has been attempted in a number of animal models, but achieving an adequate blood supply for the transplanted uterus still presents the biggest challenge. Microvascular re-anastomosis was unsuccessful in a number of animal models.

Geomagnetic imprinting predicts spatio-temporal variation in homing migration of pink and sockeye salmon.

Animals navigate using a variety of sensory cues, but how each is weighted during different phases of movement (e.g. dispersal, foraging, homing) is controversial.

Oleic Acid, deglycosylated vitamin D-binding protein, nitric oxide: a molecular triad made lethal to cancer.

Background: Oleic Acid (OA) has been shown to have anticancer properties mediated by interaction with proteins such as α-lactalbumin and lactoferrins. Therefore, we synthesized complexes of OA and Gc protein-derived macrophage activating factor (GcMAF) that inhibits per se cancer cell proliferation and metastatic potential. We hypothesised that OA-GcMAF complexes could exploit the anticancer properties of both OA and GcMAF in a synergistic manner.

Rearing in a distorted magnetic field disrupts the 'map sense' of juvenile steelhead trout.

We used simulated magnetic displacements to test orientation preferences of juvenile steelhead trout (Oncorhynchus mykiss) exposed to magnetic fields existing at the northernmost and southernmost boundaries of their oceanic range. Fish reared in natural magnetic conditions distinguished between these two fields by orienting in opposite directions, with headings that would lead fish towards marine foraging grounds. However, fish reared in a spatially distorted magnetic field failed to distinguish between the experimental fields and were randomly oriented.

An inherited magnetic map guides ocean navigation in juvenile Pacific salmon.

Migratory marine animals exploit resources in different oceanic regions at different life stages, but how they navigate to specific oceanic areas is poorly understood. A particular challenge is explaining how juvenile animals with no prior migratory experience are able to locate specific oceanic feeding habitats that are hundreds or thousands of kilometers from their natal sites. Although adults reproducing in the vicinity of favorable ocean currents can facilitate transport of their offspring to these habitats, variation in ocean circulation makes passive transport unreliable, and young animals probably take an active role in controlling their migratory trajectories.

Test of long-term uterine survival after allogeneic transplantation in rabbits.

Aim: To see if: (i) a large vessel aortocaval vascular patch technique may bring about long-term graft survival after allogeneic uterine transplantation (UTn) in a rabbit model; and (ii) fertility can be achieved following natural mating post-allogeneic UTn.

Methods: Allogeneic uterine cross transplantations were performed in New Zealand white rabbits using an aortocaval macrovascular patch harvested as part of the uterine allograft. Five rabbit recipients received a uterine graft from five unrelated donor rabbits.

GC protein-derived macrophage-activating factor decreases α--acetylgalactosaminidase levels in advanced cancer patients.

α--acetylgalactosaminidase (nagalase) accumulates in the serum of cancer patients and its activity correlates with tumor burden, aggressiveness and clinical disease progression. The administration of GC protein-derived macrophage-activating factor (GcMAF) to cancer patients with elevated levels of nagalase has been associated with a decrease of serum nagalase activity and with significant clinical benefits. Here, we report the results of the administration of GcMAF to a heterogeneous cohort of patients with histologically diverse, advanced neoplasms, generally considered as "incurable" diseases.

Effect of short-term decrease in water temperature on body temperature and involvement of testosterone in steelhead and rainbow trout, Oncorhynchus mykiss.

The Pacific salmonid species Oncorhynchus mykiss is separated into a migratory form (steelhead trout) and a non-migratory form (rainbow trout). A decrease in water temperature is likely a cue triggering downstream behavior in the migratory form, and testosterone inhibits onset of this behavior. To elucidate differences in sensitivity to water temperature decreases between the migratory and non-migratory forms and effect of testosterone on the sensitivity, we examined two experiments.

Evidence for geomagnetic imprinting as a homing mechanism in Pacific salmon.

In the final phase of their spawning migration, Pacific salmon use chemical cues to identify their home river, but how they navigate from the open ocean to the correct coastal area has remained enigmatic. To test the hypothesis that salmon imprint on the magnetic field that exists where they first enter the sea and later seek the same field upon return, we analyzed a 56-year fisheries data set on Fraser River sockeye salmon, which must detour around Vancouver Island to approach the river through either a northern or southern passageway. We found that the proportion of salmon using each route was predicted by geomagnetic field drift: the more the field at a passage entrance diverged from the field at the river mouth, the fewer fish used the passage.

Fine-scale parallel patterns in diversity of small benthic Arctic charr (Salvelinus alpinus) in relation to the ecology of lava/groundwater habitats.

It is critical to study factors that are important for origin and maintenance of biological diversity. A comparative approach involving a large number of populations is particularly useful. We use this approach to study the relationship between ecological factors and phenotypic diversity in Icelandic Arctic charr (Salvelinus alpinus).