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Full-Text Articles in Life Sciences
Bacterial Gill Disease Of Freshwater Fishes, G. L. Bullock
Bacterial Gill Disease Of Freshwater Fishes, G. L. Bullock
United States Fish and Wildlife: Staff Publications
Fish gills function as both respiratory and excretory organs. Basically they consist of a network of capillaries where blood is separated from the surrounding water by only one or two layers of cells. Proliferation of epithelial tissue, and later the loss of surface by the clubbing and fusing of lamellae, impair respiration and the excretion of nitrogenous waste materials, and disturb osmotic balance. Because these changes adversely affect the health of fish, the prevention and treatment of gill diseases are important in fish culture. Pathologic changes in gill tissues have been divided into five categories: (1) bacterial gill disease (BGD) …
Effects Of Specialized Grazing Systems On Waterfowl Production In Southcentral North Dakota, William T. Barker, Kevin K. Sedivec, Terry A. Messmer, Kenneth F. Higgins, Dan R. Hertel
Effects Of Specialized Grazing Systems On Waterfowl Production In Southcentral North Dakota, William T. Barker, Kevin K. Sedivec, Terry A. Messmer, Kenneth F. Higgins, Dan R. Hertel
United States Fish and Wildlife: Staff Publications
The recent decline in numbers of several waterfowl species (Canadian Wildlife Service and U.S. Fish and Wildlife Service 1986, U.S. Fish and Wildlife Service and Canadian Wildlife Service 1988) and poor nesting success indicates that there is insufficient production of ducks in the prairie pothole region to maintain populations at desirable levels (Klett et al. 1988). About 50 percent of the ducks in North America are produced in the prairie pothole region and about 95 percent of the production occurs on private lands (Smith et al. 1964). Thus. a major effort to reverse the decline in duck numbers should emphasize …
Enteric Redmouth Disease Of Salmonids, G. L. Bullock, R. C. Cipriano
Enteric Redmouth Disease Of Salmonids, G. L. Bullock, R. C. Cipriano
United States Fish and Wildlife: Staff Publications
Enteric redmouth disease (ERM) is a systemic bacterial infection of fishes, but is known principally for its occurrence in rainbow trout, Oncorhynchus mykiss. It was first reported in the 1950's in Idaho rainbow trout and described by Rucker (1966). In recognition of that first description, the causal organism was named Yersinia ruckeri by Ewing et al. (1978).
Viral Hemorrhagic Septicemia Of Fishes, Philip E. Mcallister
Viral Hemorrhagic Septicemia Of Fishes, Philip E. Mcallister
United States Fish and Wildlife: Staff Publications
Viral hemorrhagic septicemia (VHS), a systemic infection of various salmonid and a few nonsalmonid fishes, is caused by a rhabdovirus designated as the viral hemorrhagic septicemia virus (Office International des Epizooties 1963). The virus infection occurs in salmonids and certain other fishes of any age and may result in significant cumulative mortality. Fish that survive may become carriers. Viral hemorrhagic septicemia has been reported under various names, of which "Egtved disease" and "Infektiose Nierenschwellung und Leberdegeneration" are the best known. The viral etiology of the disease was established by Jensen (1965), and several serotypes of the virus (also known as …
Chironomidae Of The Southeastern United States: A Checklist Of Species And Notes On Biology, Distribution, And Habitat, Patrick L. Hudson, David R. Lenat, Broughton A. Caldwell, David Smith
Chironomidae Of The Southeastern United States: A Checklist Of Species And Notes On Biology, Distribution, And Habitat, Patrick L. Hudson, David R. Lenat, Broughton A. Caldwell, David Smith
United States Fish and Wildlife: Staff Publications
We provide a current listing of the species of midges (Diptera:Chironomidae) in the southeastern United States (Alabama, Florida, Georgia, North Carolina, South Carolina, and Tennessee). This checklist should aid in research on this group of insects, which have often proved useful in the assessment of water quality. We document each species' distribution and general habitat and provide the best taxonomic reference to facilitate the identification or description of species in that genus. Changes in nomenclature, unique ecological traits, bibliographic sources, or other items of information are summarized in a paragraph on each genus. Of the 10 subfamilies currently recognized in …
Endangered And Threatened Wildlife And Plants; Neosho Madtom Determined To Be Threatened
Endangered And Threatened Wildlife And Plants; Neosho Madtom Determined To Be Threatened
United States Fish and Wildlife: Staff Publications
The Fish and Wildlife Service (Service) determines a fish, the Neosho madtom (Noturusplocidus), to be a threatened species under the authority of the Endangered Species Act of 1973 (Act), as amended. The madlom is currently known from the Neosho River (Grand Riverin Oklahoma) drainage: in the Neosho, Cottonwood, and Spring Rivers in southeastern Kansas, southwestern Missouri, and northeastern Oklahoma. Habitat destruction andmodification, principally due to impoundments, dredging activities, and increased water demands, have decreased the distribution and abundance of the species and isolated it into three populations. This rule identifies the taxon as one in need of conservation, …