Chronicles of Oklahoma

Article chronicles the establishment and history of the First Regiment of United States Dragoons, an elite regiment of mounted soldiers who patrolled the frontier

Experimental Infection of Cats and Dogs with West Nile Virus

Domestic dogs and cats were infected by mosquito bite and evaluated as hosts for West Nile virus (WNV). Viremia of low magnitude and short duration developed in four dogs but they did not display signs of disease. Four cats became viremic, with peak titers ranging from 103.0 to 104.0 PFU/mL. Three of the cats showed mild, non-neurologic signs of disease. WNV was not isolated from saliva of either dogs or cats during the period of viremia. An additional group of four cats were exposed to WNV orally, through ingestion of infected mice. Two cats consumed an infected mouse on three consecutive days, and two cats ate a single infected mouse. Viremia developed in all of these cats with a magnitude and duration similar to that seen in cats infected by mosquito bite, but none of the four showed clinical signs. These results suggest that dogs and cats are readily infected by WNV. The high efficiency of oral transmission observed with cats suggests that infected prey animals may serve as an important source of infection to carnivores. Neither species is likely to function as an epidemiologically important amplifying host, although the peak viremia observed in cats may be high enough to infect mosquitoes at low efficiency

Comparison of Predator Avoidance Capabilities with Corticosteroid Levels Induced by Stress in Juvenile Coho Salmon

The relationship between predator avoidance deficits induced by a simple handling stress and the level of plasma corticosteroids was determined for juvenile coho salmon Oncorhynchus kisutch. Groups of fish were held out of water for 1 min, then allowed to recover from this stress for 1, 90, or 240 min. After each recovery period, some unstressed and stressed fish were sampled for plasma cortisol, and others were subjected to predation by lingcod Ophiodon elongatus. Levels of corticosteroids in stressed fish remained high throughout the 240-min period of recovery, but predator avoidance returned to control levels in less than 90 min. Results suggest that juvenile coho salmon quickly recover basic survival skills of predator avoidance after mild stress, even though cortisol levels continue to indicate a stressed condition.Keywords: Oncorhynchus kisutch smolts, Corticosteroids, stress reactionKeywords: Oncorhynchus kisutch smolts, Corticosteroids, stress reactio

Effects of juvenile steelhead on juvenile chinook salmon behavior and physiology

Experiments were designed to determine whether and how steelhead Oncorhynchus mykiss affect chinook salmon O. tshawytscha when the two species are confined together. In a behavioral experiment, we observed groups of juvenile chinook salmon and steelhead together and groups of chinook salmon alone to determine whether the steelhead were aggressive and their presence changed the behavior of chinook salmon. We also performed two runs of a physiological experiment to determine whether the addition of steelhead to tanks containing chinook salmon would stress the chinook salmon, as determined by a change in their plasma cortisol levels. Behavioral changes were observed in the chinook salmon when they were held with steelhead; they reduced their movements, darted less, were attacked up to 16 times as often, and were found less frequently in the shade than chinook salmon held without steelhead. Steelhead were found to establish territories and defend them with chases, charges, and nips. In their attempts to establish and defend territories, the steelhead attacked the chinook salmon as often as they attacked other steelhead, but the chinook salmon showed little aggression toward the steelhead. Cortisol concentrations were significantly higher for chinook salmon in tanks receiving steelhead than in tanks receiving additional chinook salmon or no additional fish after 2 h (in one of the two experimental runs) and after 32 h (in both experimental runs; combined data). These results suggest that confining steelhead and chinook salmon together, such as in raceways and barges in the Columbia River system and in other situations, is stressful to the chinook salmon

Sexual Signal Evolution Outpaces Ecological Divergence during Electric Fish Species Radiation

Natural selection arising from resource competition and environmental heterogeneity can drive adaptive radiation. Ecological opportunity facilitates this process, resulting in rapid divergence of ecological traits in many celebrated radiations. In other cases, sexual selection is thought to fuel divergence in mating signals ahead of ecological divergence. Comparing divergence rates between naturally and sexually selected traits can offer insights into processes underlying species radiations, but to date such comparisons have been largely qualitative. Here, we quantitatively compare divergence rates for four traits in African mormyrid fishes, which use an electrical communication system with few extrinsic constraints on divergence. We demonstrate rapid signal evolution in the Paramormyrops species flock compared to divergence in morphology, size, and trophic ecology. This disparity in the tempo of trait evolution suggests that sexual selection is an important early driver of species radiation in these mormyrids. We also found slight divergence in ecological traits among closely related species, consistent with a supporting role for natural selection in Paramormyrops diversification. Our results highlight the potential for sexual selection to drive explosive signal divergence when innovations in communication open new opportunities in signal space, suggesting that opportunity can catalyze species radiations through sexual selection, as well as natural selection

Capture-Related Stressors Impair Immune System Function in Sablefish

The sablefish Anoplopoma fimbria is a valuable North Pacific Ocean species that, when not targeted in various commercial fisheries, is often a part of discarded bycatch. Predictions of the survival of discarded fish are dependent on understanding how a fish responds to stressful conditions. Our objective was to describe the immunological health of sablefish exposed to capture stressors. In laboratory experiments designed to simulate the capture process, we subjected sablefish to various stressors that might influence survival: Towing in a net, hooking, elevated seawater and air temperatures, and air exposure time. After stress was imposed, the in vitro mitogen-stimulated proliferation of sablefish leukocytes was used to evaluate the function of the immune system in an assay we validated for this species. The results demonstrated that regardless of fishing gear type, exposure to elevated seawater temperature, or time in air, the leukocytes from stressed sablefish exhibited significantly diminished proliferative responses to the T-cell mitogen, concanavalin A, or the B-cell mitogen, lipopolysaccharide. There was no difference in the immunological responses associated with seawater or air temperature. The duration and severity of the capture stressors applied in our study were harsh enough to induce significantly elevated levels of plasma cortisol and glucose, but there was no difference in the magnitude of levels among stressor treatments. These data suggest that immunological suppression occurs in sablefish subjected to capture-related stressors. The functional impairment of the immune system after capture presents a potential reason why delayed mortality is possible in discarded sablefish. Further studies are needed to determine whether delayed mortality in discarded sablefish can be caused by increased susceptibility to infectious agents resulting from stressor-mediated immunosuppression.Keywords: Anoplopoma fimbria, immune system, stress, bycatc

The establishment and utility of Sweha-Reg: a Swedish population-based registry to understand hereditary angioedema

<p>Abstract</p> <p>Background</p> <p>The importance of acquiring comprehensive epidemiological and clinical data on hereditary angioedema has increasingly caught the attention of physicians and scientists around the world. The development of networks and creation of comprehensive policies to improve care of people suffering from rare diseases, such as hereditary angioedema, is a stated top priority of the European Union.</p> <p>Hereditary angioedema is a rare disease, that it may be life-threatening. Although the exact prevalence is unknown, current estimates suggest that it is 1/10,000–1/150,000 individuals. The low prevalence requires combined efforts to gain accurate epidemiological data on the disease and so give us tools to reduce morbidity and mortality, and improve quality of life of sufferers.</p> <p>Methods</p> <p>Sweha-Reg is a population-based registry of hereditary angioedema in Sweden with the objectives of providing epidemiological data, and so creates a framework for the study of this disease. The registry contains individual-based data on diagnoses, treatments and outcomes.</p> <p>Conclusion</p> <p>The present manuscript seeks to raise awareness of the existence of Sweha-Reg to stimulate the international collaboration of registries. A synthesis of data from similar registries across several countries is required to approach an inclusive course understanding of HAE.</p

Occupational Risks during a Monkeypox Outbreak, Wisconsin, 2003

Veterinary staff were at high risk; standard veterinary infection-control guidelines should be followed