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At least 19 recordsLinked to original sources
USGS2013

Parasitic infection by larval helminths in Antarctic fishes: pathological changes and impact on the host body condition index

We examined pathological changes and relationship between body condition index (BCI) and parasitic infection in 5 species of fish, including 42 icefish Chionodraco hamatus (Channichtyidae), 2 dragonfish Cygnodraco mawsoni (Bathydraconidae), 30 emerald rock cod Trematomus bernacchii, 46 striped rock cod T. hansoni and 9 dusty rock cod T. newnesi (Nototheniidae) from the Ross Sea, Antarctica. All parasites were identified by a combination of morphology and mtDNA cytochrome-oxidase-2 sequence (mtDNA cox2) analysis, except Contracaecum osculatum s.l., for which only the latter was used. Five larval taxa were associated with pathological changes including 2 sibling species (D and E) of the C. osculatum species complex and 3 cestodes including plerocercoids of a diphyllobothridean, and 2 tetraphyllidean forms including cercoids with monolocular and bilocular bothridia. The most heavily infected hosts were C. hamatus and C. mawsoni, with C. hamatus most often infected by C. osculatum sp. D and sp. E and diphyllobothrideans, while C. mawsoni was most often infected with tetraphyllidean forms. Histologically, all fish showed varying severity of chronic inflammation associated with larval forms of helminths. Diphyllobothrideans and C. osculatum spp. were located in gastric muscularis or liver and were associated with necrosis and mild to marked fibrosis. Moderate multifocal rectal mucosal chronic inflammation was associated with attached tetraphyllidean scolices. C. hamatus showed a strong negative correlation between BCI and parasite burden.

Diseases of Aquatic Organisms↗
USGS2017

In memoriam - William Toshio (Tosh) Yasutake, 1922-2016

William Toshio (Tosh) Yasutake, 1922-2016 passed away peacefully at home on December 12, 2016, at the age of 94. He is survived by Fumi, his wife of 66 years, as well as four children and six grandchildren. With his death, the fish health community has lost an outstanding scientist as well as a kind, unassuming, and wonderful human being. Tosh was born on June 10, 1922, in Seattle, Washington, to Jack and Hide Yasutake. He was in his first year of studies at the University of Washington when Pearl Harbor was attacked by Imperial Japan on December 7, 1941. Following the attack, Tosh and his family (father, mother, sister, and two brothers) were among the 110,000–120,000 people of Japanese ancestry who were forced from their homes on the Pacific coast and incarcerated in internment camps in the interior. In June 1942, Tosh enlisted in the U.S. Army, serving as an unarmed combat medic in the famed 442nd Regimental Combat Team, the most decorated unit for its size and length of service in the history of American warfare. Wounded in October 1944 during the Vosges Mountains campaign near Bruyères, France, Tosh was evacuated and missed the ensuing battle to rescue the “Lost Battalion,” at which his replacement was killed. Tosh returned to action in Italy in February 1945 and served until the end of the war in Europe, earning both a Purple Heart and a Bronze Star for bravery. In October 2010, the Congressional Gold Medal was awarded to the 442nd Regimental Combat Team, and in 2012 the surviving members were made chevaliers of the French Légion d’Honneur for actions contributing to the liberation of France in World War II. After the war, Tosh returned to the University of Washington on the GI Bill and received a B.S. degree in zoology in 1951. In 1953 he began his research career at the U.S. Fish and Wildlife Service’s Western Fish Nutrition Laboratory at Cook, Washington, where he conducted pioneering research on nutritional fish diseases with John Halver. Tosh was one of the first to recognize hepatomas in hatchery-reared Rainbow Trout and helped to trace the disease to an aflatoxin produced by the mold Aspergillus flavis , which grew during the storage of ingredients for fish diets. In 1960, he transferred to the Western Fisheries Research Center (WFRC) in Seattle (then called the Western Fish Disease Laboratory) to start a fish pathology diagnostic laboratory. There he described the histopathology of diseases of economically important fishes, identified etiologic agents, and worked with hatchery biologists to improve the health, quality, and survival of salmonids released from federal and state hatcheries. Tosh was instrumental in recognizing that the viruses of Oregon sockeye disease and Chinook Salmon virus disease were one entity and in giving the disease its present name: infectious hematopoietic necrosis. In recognition of his pioneering research, Tosh was awarded a doctorate in fish pathology by the University of Tokyo in 1980, the first American to have been so honored. In 1983, he published his classic textbook The Microscopic Anatomy of Salmonids: An Atlas , which quickly became a standard reference work in fish pathology and is still in wide use today. For his outstanding career achievements, in 1987 Tosh received the S. F. Snieszko Distinguished Service Award, the highest honor bestowed by the American Fisheries Society’s Fish Health Section (AFS–FHS). Tosh retired in 1988 but continued his research at the WFRC as a senior scientist emeritus, providing technical assistance to federal and state agencies and to the aquaculture industry worldwide. His culminating project was to digitize his lifetime collection of photomicrographs and prepare an atlas, “Histopathology of Selected Parasitic Salmonid Diseases: A Color Atlas,” that is now posted on the Web sites of the WFRC and the AFS–FHS. Although his presence will be sorely missed, his research contributions have become part of the foundation of today’s knowledge of fisheries biology and have assured him a place in history.

Journal of Aquatic Animal Health↗
USGS2020

Assessment of microscopic pathology in fishes collected at sites impacted by wood tar in Pennsylvania

In an effort to determine whether fish populations in an area affected by wood tar waste exhibited health effects, fish were collected and analyzed with histopathology. Multiple species, including Mottled Sculpin ( Cottus bairdii ), Creek Chub ( Semotilus atromaculatus ), White Sucker ( Catostumus commersonii ), Redside Dace ( Clinostomus elongatus ), Common Shiner ( Luxilus cornutus ), and Western Blacknose Dace ( Rhinichthys obtusus ) were sampled from a reference site, Meade Run, and potentially affected streams, Kinzua Creek and Threemile Run, in northwestern Pennsylvania. A full histopathological evaluation was conducted to identify microscopic abnormalities potentially associated with wood tar exposure. The evaluation identified primarily parasites associated with tissue changes. These included microsporidian parasites in the ovaries of Common Shiner and Western Blacknose Dace; myxozoan cysts in the muscle of Common Shiner, Creek Chub, and Western Blacknose Dace; trematode cysts in the muscle of Creek Chub, Redside Dace and Common Shiner; and coccidia in spleen or pancreas of Creek Chub and Common Shiner. Microscopic abnormalities potentially associated with chemical exposure included ceroid/lipofuscin deposits in the meninges of the olfactory lobe of the brain in Common Shiner, Western Blacknose Dace, and Creek Chub, as well as bile duct proliferation and a biliary tumor in Creek Chub. Overall, the findings did not reveal significant microscopic pathology consistent with exposure to wood tar waste.

Pennsylvania↗
USGS1997

Aromatic hydrocarbon pathology in fish following a large spill into the Nemadji River, Wisconsin, USA

On June 30, 1992, a train accident resulted in a rail car releasing 114,000 L of a complex mixture of aromatic hydrocarbons into the Nemadji River, a tributary of Lake Superior near Superior, Wisconsin (Table 1). Although the majority of the spilled material evaporated, damage to aquatic life was extensive. Several thousand fishes were killed and an inestimable number were exposed to low concentrations (< 5 mg/L) of the chemical concentrate for several weeks (Allen 1993). Fishes that survived the spill were examined within 7 days of exposure to determine the extent of injury when compared to fishes collected from the reference site. The liver, spleen, gill, and head kidney were examined for histopathology. Blood was collected to determine the severity of liver damage reflected by the presence of the serum enzymes (aspartate aminotransferase, alanine aminotransferase, and d - glutamyl transferase).

Bulletin of Environmental Contamination and Toxico↗
USGS1961

Trout hepatoma--a preliminary report

Fish pathology and its role in fish culture were brought into prominence in the spring of 1960 by the disclosure of a high incidence of hepatomas in hatchery-reared rainbow trout. The current problem came to light as the result of a routine inspection of live trout shipments at a California border fish-disease checking station. This service is performed by personnel of the California Department of Fish and Game to preclude the introduction or further spread of communicable fish diseases into California watersheds. Collaborative studies which followed revealed the nationwide distribution of the disease. This unusual disease soon attracted the attention of the Bureau of Sport Fisheries and Wildlife, the Food and Drug Administration, Public Health Service, and several western State health and conservation agencies.

Progressive Fish-Culturist↗
USGS1992

Identification of viral hemorrhagic septicemia virus isolated from Pacific cod Gadus macrocephalus in Prince William Sound Alaska, USA

Ulcerative slun tissues from 2 Pacific cod Gadus rnacrocephalus caught in Prince William Sound, Alaska, USA, were examined for virus by Fish Pathology staff within the F.R.E.D. Division of the Alaska Department of Fish and Game. Six days after inoculation of Epitheliorna papulosum cyprini (EPC) cells at 14"C, diffuse rounding and lifting of cells from the monolayers suggestive of cytopathlc effect became visible in the lower sample dilutions. Ultrastructural examinations of affected EPC cells showed rhabdovirus particles within cytoplasmic vacuoles and on the cell surface membranes. Virus isolates from both cod were subsequently confirmed as viral hemorrhagic septicemia virus (VHSV) by serum neutralizabon and immunoblot assay. This is the first VHSV isolated from Pacific cod, which represents a new host species for the virus. Histologically, cod skin ulcers appeared to be caused by a foreign-body-type inflammatory response to foci of protozoa resembling X cells that also had plasmodial stages. Whether the rhabdovirus was incidental to the slun lesion or played a role in its etiology remains to be determined. The possible relationship between thls virus and the recent occurrences of VHSV in anadromous salmoruds from Washington State, USA, is discussed.

Diseases of Aquatic Organisms↗
USGS2009

Assessment of the "fish tumors or other deformities" beneficial use impairment in brown bullhead (Ameiurus nebulosus): II. Liver neoplasia

Liver pathology of fishes, including neoplastic and preneoplastic lesions, is widely used as an indicator of exposure to anthropogenic contaminants. By definition, the "fish tumor or other deformities" beneficial use impairment (BUI) at Great Lakes Areas of Concern (AOC) includes neoplastic and preneoplastic liver lesions in brown bullhead (Ameiurus nebulosus) or suckers. Unfortunately, adequate guidelines for defining neoplastic and preneoplastic liver lesions or determining rates at unimpacted control sites were not provided and different criteria have been used. In some cases, only neoplastic changes were used to calculate tumor prevalence, in some both neoplastic and preneoplastic changes and in some it is difficult to determine which changes were included. Using standardized criteria, the prevalence of liver neoplasia was compared at eight AOC during 1998-2000. The Cuyahoga River had the highest prevalence (25.0%), while the Maumee River had the lowest (3.9%). The Buffalo (4.8%), Detroit (5.9%), Ashtabula (6.8%), Niagara (7.5%) and Black (8.9%) rivers were intermediate, as was Presque Isle Bay (7.1%). From 2002 to 2007 the prevalence of liver neoplasia at Presque Isle Bay ranged from a low of 2.1% (2002) to a high of 12.0% (2007). Non-AOC sites, as potential reference sites, also were monitored during this time. By combining years and sites, the prevalence of liver neoplasia in bullhead (aged 2 to 12 years) at inland lakes was 0.7%, at bays/harbors was 1.6% and at tributary sites was 4.1%. This is the same trend (inland lakes < bays/harbors < tributaries < Presque Isle Bay) noted for orocutaneous neoplasms.

Journal of Great Lakes Research↗
USGS1970

Control methods for snail-borne zoonoses

All trematodes which cause infections and diseases in humans (zoonoses) require snails for their first intermediate host. Some have additional intermediate hosts such as crustaceans, fishes and frogs. In this paper I have discussed the use of various procedures for controlling snail populations thereby reducing the population of trematodes whose cercariae penetrate the skin of man, or which are acquired by eating raw aquatic vegetation such as watercress, or which cause pathology in fish. Biological, chemical, and physical snail control techniques are discussed. The most promising molluscucides are copper compounds, Bayluscide, biocidal rubber and molluscicidal bait.

Journal of Wildlife Diseases↗
USGS1983

Factors affecting dietary requirement and deficiency signs of L-tryptophan in rainbow trout

Two experiments were conducted to determine the concentration of dietary tryptophan needed for optimal growth and survival of fingerling rainbow trout ( Salmo gairdneri ), to characterize signs of tryptophan deficiency, and to ascertain the effects of niacin on deficiency signs. Test diets containing either hydrolyzed or intact casein were fed with graded levels of added L-tryptophan (0.0, 0.25, 0.50, 0.75 and 1.0 g/100 g protein). Maximum growth occurred at 0.75 and 0.50 g tryptophan in fish fed hydrolyzed and intact casein, respectively. Changes in mineral and amino acid mixtures in the intact casein diet yielded a cation-anion (Na + K - Cl) balance of + 15.3 meq/100 g diet and pH of 6.44, compared with a balance of -21.3 and -25 meq, and pH 5.8 and 4.4 for unmodified hydrolyzed and intact casein diets, respectively. Analysis of growth by the polynomial regression function; Y = 0.16 + 0.429 X - 0.26 X 2 , where Y = mean daily gain in grams, and X = grams of added tryptophan/100 g protein, predicted that at least 0.58 g of tryptophan was needed for maximum weight gain. Analysis of apparent pathology-free fish by the function; Y = 34.33 + 147.33 X = 83.87 X 2 , where Y = percentage with no signs of deficiency, and X = grams of added tryptophan, predicted that 0.63 g tryptophan/100 g protein was needed for optimum health scores. Deletion of supplemental niacin did not affect fish response to tryptophan.

Journal of Nutrition↗
USGS1956

Tissue damage in salmonids caused by Halisidota argentata Packard

During the histological examination of a collection of wild and hatchery salmonids, a peculiar foreign body was occasionally observed in various organs, particularly in the viscera. These objects, usually accompanied by a focal inflammation, were observed in 10 of 75 samples of wild trout and salmon collected in Oregon and Washington and were believed to represent an unknown type of parasitism. Their identity remained obscure until a massive concentration was observed in the tissues of wild coho salmon, ( Oncorhynchus kisutch ), from Minter Creek on the Olympic peninsula of Washington and in hatchery coho salmon from the Minter Creek Biological Station. The distribution of the structures suggested the intestinal tract as a point of origin. Subsequent stomach examinations revealed small, partially digested insect fragments with many long, spine-covered hairs. The insects were identified as second or third instars of the lepidopteran larvae, Halisidota argentata Packard. The spine-covered hairs penetrated the stomach wall and produced the observed lesions by working in an apparent porcupine quill-fashion throughout the body of the fish. The pathology of the Minter Creek salmon was sufficiently extensive to merit a description of the condition for the benefit of other workers who may encounter this rather unusual phenomenon and confuse it with an actual parasitic infection.

Oregon, Washington↗
USGS1978

Spray vaccination: A method for the immunization of fish

An economical, efficacious vaccine delivery system for immunizing fish has been developed which employs a liquid spray apparatus operated at pressures up to 7.0 kg/cm 2 (0 to 100 lb/in 2 ). A bacterin consisting of formalin-killed Vibrio anguillarum culture was both antigenic and immunogenic when sprayed on coho salmon(Oncorhynchus kisutch)and rainbow trout(Salmo gairdneri). The technique, referred to as spray(shower)vaccination, was found to confer higher levels of immunity against virulent V. anguillarum than oral vaccination.

Fish Pathology↗
USGS1979

Histopathology of yearling sockeye salmon (Oncorhynchus nerka) infected with infectious hematopoietic necrosis (IHN)

Infectious hematopoietic necrosis (IHN) is generally believed to be a virus disease of very young salmonids. In recent years there have been increasing numbers of unpublished reports that this disease has been occurring uncharacteristically in fish as old as 7-14 months. Sockeye salmon (Oncorhynchus nerka) of this age the histological changes were not severe. Intestinal tract granular cells thought to be pathognomic in young fish were conspicuously absent. Kidney imprints showed necrobiotic bodies however, and subtle changes were observed in the spleen and kidney hematopoietic tissue.

Fish Pathology↗