Environmentally induced oxidative stress in aquatic animals

The ecosystem response to the 1989 spill of oil from the Exxon Valdez into Prince William Sound, Alaska, shows that current practices for assessing ecological risks of oil in the oceans and, by extension, other toxic sources should be changed. Previously, it was assumed that impacts to populations derive almost exclusively from acute mortality. However, in the Alaskan coastal ecosystem, unexpected persistence of toxic subsurface oil and chronic exposures, even at sublethal levels, have continued to affect wildlife. Delayed population reductions and cascades of indirect effects postponed recovery. Development of ecosystem-based toxicology is required to understand and ultimately predict chronic, delayed, and indirect long-term risks and impacts.

https://science.sciencemag.org/content/sci/302/5653/2082.full.pdf

Long-Term Ecosystem Response to the Exxon Valdez Oil Spill

DNA sequencing with chain terminating inhibitors

Defects in cardiac function precede morphological abnormalities in fish embryos exposed to polycyclic aromatic hydrocarbons.

principles and techniques of electron microscopy principles and techniques of electron microscopy electron microscopy and optics: general textbooks principles and techniques of electron microscopy principles and techniques of electron microscopy principles and techniques of digital holographic microscopy scanning electron microscopy cathodoluminescence of quartz introduction to transmission/scanning transmission principles and technique of fluorescence microscopy by m principles and techniques of electron microscopy: volume 1 principles of the phase contrast (electron) microscopy principles and techniques of electron microscopy lecture 1 the principles of microscopy principles in light microscopy scanning techniques in electron microscopy

Principles and Techniques of Electron Microscopy

A herpesvirus was isolated from adult koi, a strain of common carp Cyprinus carpio, suffering mass mortality in two outbreaks-one in the mid-Atlantic region of the United States and the second in Israel. The principal external signs of dying fish were pale and irregularly colored gills. There were few consistent internal signs in either outbreak. The most prominent microscopic lesions were in the gills, where hyperplasia and necrosis of the epithelium were severe. Other lesions included interstitial nephritis, splenitis, and enteritis. Affected cells often contained nuclei with marginated chromatin and faint intranuclear inclusions. Typical herpesvirus particles were present in branchial epithelial cells, hepatocytes, and among circulating leukocytes. Inoculations of the koi fin (KF-1) cell line with tissue extracts from the gill and kidney-spleen resulted in cytopathic effects characterized by severe vacuolation first detected after 7 d incubation at 20°C. Exposures of adult koi to the herpesvirus as propagated in KF-1 cells by bath or intraperitoneal injections resulted in 80-100% mortality during a 26-d period, and the virus was reisolated from the gill, kidney, liver, spleen, intestine, and brain of dead fish. The viral agents from koi in Israel and the United States appear to be similar if not identical; both could be distinguished from Herpesvirus cyprini by indirect fluorescent antibody tests with rabbit anti-H. cyprini serum. Other factors should be examined but we strongly suspect that this newly recognized koi herpesvirus (KHV) has the potential to be a significant cause of mortality among koi and presumably common carp.

A Herpesvirus Associated with Mass Mortality of Juvenile and Adult Koi, a Strain of Common Carp

Development of pink salmon (Oncorhynchus gorbuscha) incubating in gravel contaminated with weathered Prudhoe Bay crude oil was retarded at concentrations as low as 55.2 μg oil/g gravel. Larvae expo...

Ascites, premature emergence, increased gonadal cell apoptosis, and cytochrome P4501A induction in pink salmon larvae continuously exposed to oil-contaminated gravel during development

The effect of chronic chromium exposure on the health of Chinook salmon (Oncorhynchus tshawytscha).

Nous avons evalue les degâts subletaux subis par des larves de hareng du Pacifique (Clupea pallasi) dans les eaux du golfe du Prince-William (Alaska), a la suite du deversement de petrole, en mars 1989, cause par le naufrage de l'Exxon Valdez. De 1989 a 1991, nous'avons preleve des masses d'oeufs a des plages polluees et non polluees, et nous avons assure leur incubation jusqu'a l'eclosion. Nous avons examine les larves nouvellement ecloses pour voir si elles etaient atteintes de malformations morphologiques (du squelette, de la region crânofaciale et du repli cutane des nageoires), d'anomalies cytogenetiques (aberrations associees aux stades de l'anaphase et de la telophase) et de lesions histopathologiques. En 1989, les larves de hareng provenant des deux secteurs contamines (la baie Rocky sur l'ile Montague et l'ile Naked) presentaient significativement plus de malformations morphologiques et d'anomalies cytogenetiques que les larves provenant du secteur non contamine (la baie Fairmont). L'importance des degâts morphologiques et cytogenetiques a ete mise en correlation avec l'exposition au petrole chez des moules indigenes de la baie. Les larves ne manifestaient pas de lesions histopathologiques pouvant etre associees au petrole. En 1990 et en 1991, nous n'avons pas pu detecter d'effets genetiques et d'anomalies du developpement attribuables au petrole.

Sublethal effects of the (Exxon Valdez) oil spill on herring embryos and larvae: morphological, cytogenetic, and histopathological assessments, 19891991

Pacific herring Clupea pallasi populations in Prince William Sound, Alaska, USA, declined from an estimated 9.8 x 10(7) kg in 1992 to 1.5 x 10(7) kg in 1994. To determine the role of disease in population decline, 233 Pacific herring from Prince William Sound were subjected to complete necropsy during April 1994. The North American strain of viral hemorrhagic septicemia virus (VHSV) was isolated from 11 of 233 fish (4.7%). VHSV was significantly related to myocardial mineralization, hepatocellular necrosis, submucosal gastritis, and meningoencephalitis. Ichthyophonus hoferi infected 62 of 212 (29%) fish. I. hoferi infections were associated with severe, disseminated, granulomatous inflammation and with increased levels of plasma creatine phosphokinase (CPK) and aspartate aminotransferase (AST). I. hoferi prevalence in 1994 was more than double that of most previous years (1989 to 1993). Plasma chemistry values significantly greater (p < 0.01) in males than females included albumin, total protein, cholesterol, chloride, glucose, and potassium; only alkaline phosphatase was significantly greater in females. Hypoalbuminemia was relatively common in postspawning females; other risk factors included VHSV and moderate or severe focal skin reddening. Pacific herring had more than 10 species of parasites, but they were not associated with significant lesions. Two of the parasites have not previously been described: a renal intraductal myxosporean (11% prevalence) and an intestinal coccidian (91% prevalence). Transmission electron microscopy of a solitary mesenteric lesion revealed viral particles consistent with lymphocystis virus. No fish had viral erythrocytic necrosis (VEN). Prevalence of external gross lesions and major parasites was not related to fish age, and fish that were year-lings at the time of the 1989 'Exxon Valdez' oil spill (1988 year class) had no evidence of increased disease prevalence.

/pdf/viral-hemorrhagic-septicemia-virus-ichthyophonus-hoferi-and-39xqz9z2vk.pdf

Viral hemorrhagic septicemia virus, Ichthyophonus hoferi, and other causes of morbidity in Pacific herring Clupea pallasi spawning in Prince William Sound, Alaska, USA.

Gary D. Marty

Papers

A Herpesvirus Associated with Mass Mortality of Juvenile and Adult Koi, a Strain of Common Carp

Ascites, premature emergence, increased gonadal cell apoptosis, and cytochrome P4501A induction in pink salmon larvae continuously exposed to oil-contaminated gravel during development

The effect of chronic chromium exposure on the health of Chinook salmon (Oncorhynchus tshawytscha).

Sublethal effects of the (Exxon Valdez) oil spill on herring embryos and larvae: morphological, cytogenetic, and histopathological assessments, 19891991

Viral hemorrhagic septicemia virus, Ichthyophonus hoferi, and other causes of morbidity in Pacific herring Clupea pallasi spawning in Prince William Sound, Alaska, USA.