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Full-Text Articles in Animal Sciences

Toxic Responses Of The Fish Nervous System, Steven P. Bradbury, Richard W. Carlson, Tala R. Henry, Stephanie Padilla, John Cowden Jan 2008

Toxic Responses Of The Fish Nervous System, Steven P. Bradbury, Richard W. Carlson, Tala R. Henry, Stephanie Padilla, John Cowden

Steven P. Bradbury

Few of the approximately 70,000 chemicals on the Toxic Substances Control Act inventory or the 1000 to 1600 new chemicals introduced each year in the United States have been tested for neurotoxicity to support risk assessments (NRC, 1992), even though it is estimated that 5 to 10% of them are likely to be neurotoxic. Neurotoxicity has been defined as adverse effects of physical, biological, or chemical agents on the structure or function of the nervous system in developing or adult organisms (Philbert et al., 2000). From a human health risk assessment perspective, the potential for neurotoxic effects associated with synthetic …


The Ivory-Billed Woodpecker In Mississippi?, Stephen J. Dinsmore Jan 2005

The Ivory-Billed Woodpecker In Mississippi?, Stephen J. Dinsmore

Stephen J Dinsmore

In April the environmental community received a real surprise--the Ivory-billed Woodpecker, long thought to be extinct, had apparently been rediscovered in Arkansas! As the news unfolded, the world learned that a team of researchers had been tracking at least one woodpecker, a lone male, for more than a year in the Cache River region of east-central Arkansas. The rediscovery of a bird presumed extinct for more than 60 years subsequently galvanized the environmental community and garnered much-needed support for the preservation of the Southeast's remaining old growth bottomland forests and endangered species recovery.


Waterfowl Abundance And Distribution In The Mississippi Delta, Stephen J. Dinsmore, Aaron T. Pearse, Richard M. Kaminski, Kenneth J. Reinecke Jan 2005

Waterfowl Abundance And Distribution In The Mississippi Delta, Stephen J. Dinsmore, Aaron T. Pearse, Richard M. Kaminski, Kenneth J. Reinecke

Stephen J Dinsmore

During mornings of empty skies, a duck hunter has plenty of time to ponder the question, "Where are all the ducks?" Invariable, the distraught hunter arrives at an unhappy conclusion: the ducks are not going to show up, so they must be elsewhere. The typical progression of an unsuccessful morning of hunting leads to multiple explanations as to why there weren't any ducks, such as mild winter temperatures in and north of Mississippi, not enough rain to attract ducks, too much rain and the ducks are scattered, the region doesn't have enough food to attract and hold ducks, the ducks …


Hamiota, A New Genus Of Freshwater Mussel (Bivalvia: Unionidae) From The Gulf Of Mexico Drainages Of The Southeastern United States, Kevin J. Roe, Paul D. Hartfield Jan 2005

Hamiota, A New Genus Of Freshwater Mussel (Bivalvia: Unionidae) From The Gulf Of Mexico Drainages Of The Southeastern United States, Kevin J. Roe, Paul D. Hartfield

Kevin J. Roe

Hamiota, a new genus of freshwater mussel containing four species formerly assigned to the genus Lampsilis Rafinesque, 1820, is described. In addition to the genus Lampsilis, members of Hamiota had previously been placed in the genera Villosa Frierson, 1927, and Ligumia Swainson, 1840. Several characters including the packaging of their larvae in a superconglutinate lure to attract host fishes, placement and shape of the marsupia, and release of glochidia through the excurrent siphon, support the recognition of these species as a distinct genus.


Phylogeographic Analysis Of The Threatened And Endangered Superconglutinate-Producing Mussels Of The Genus Lampsilis (Bivalvia: Unionidae), Kevin J. Roe, Charles Lydeard, Paul D. Hartfield Jan 2001

Phylogeographic Analysis Of The Threatened And Endangered Superconglutinate-Producing Mussels Of The Genus Lampsilis (Bivalvia: Unionidae), Kevin J. Roe, Charles Lydeard, Paul D. Hartfield

Kevin J. Roe

Several species of freshwater unionid mussels in the genus Lampsilis exhibit a remarkable reproductive strategy. Female mussels of these species enclose their larvae in a minnow-like lure, called a ‘superconglutinate’, to attract piscivorous fishes. When a fish attempts to ingest the superconglutinate the lure ruptures and the larvae are released to parasitize the fish. Of the four species of mussel which exhibit this strategy and are endemic to the Gulf Coast drainages of the southeastern United States, three are protected under the Endangered Species Act, and one is recognized as imperilled. Phylogenetic analysis of nucleotide sequences of the mitochondrial 16S …


Species Delineation And The Identification Of Evolutionarily Significant Units: Lessons From The Freshwater Mussel Genus Potamilus (Bivalvia: Unionidae), Kevin J. Roe, Charles Lydeard Jan 1998

Species Delineation And The Identification Of Evolutionarily Significant Units: Lessons From The Freshwater Mussel Genus Potamilus (Bivalvia: Unionidae), Kevin J. Roe, Charles Lydeard

Kevin J. Roe

Accurate identification of biological entities is critical to the timely and efficient preservation of biodiversity. Concepts that define segments of biological diversity--species and evolutionarily significant units (ESUs)--should reflect our current knowledge of the biological world. Conflation of different hierarchical definitions of taxa has the potential to obscure distinct biological entities in need of protection. The concept of the ESU has been criticized because it includes within its definition distinct biological entities that otherwise would be recognized as species. Herein we evaluate several versions of the evolutionary significant unit concept and provide as a case study an analysis of geographic variation …


Identification Of A Fish Host Of The Inflated Heelsplitter Potamilus Inflatus( Bivalvia: Unionidae) With A Description Of Its Glochidium, Kevin J. Roe, Andrew M. Simons, Paul Hartfield Jan 1997

Identification Of A Fish Host Of The Inflated Heelsplitter Potamilus Inflatus( Bivalvia: Unionidae) With A Description Of Its Glochidium, Kevin J. Roe, Andrew M. Simons, Paul Hartfield

Kevin J. Roe

A survey of the fishes of the lack Warrior River was undertaken to determine fish host(s) of the federally threatened inflated heelsplitter, Potamilus inflatus. Seven hundred-twenty individual fishes representing 30 species were examined; mussel glochidia were found on 10 individual fishes representing nine species. Potamilus inflatus glochidia were only found infesting one freshwater drum (Aplodinotus grunniens), which is concordant with previous findings for the genus Potamilus. The morphology of P. inflatus glochidia is described and compared to P. purpuratus.


2,3, 7,8-Tetrachlorodibenzo-P-Dioxin, Steven P. Bradbury Jan 1996

2,3, 7,8-Tetrachlorodibenzo-P-Dioxin, Steven P. Bradbury

Steven P. Bradbury

Since 1985, the United States Environmental Protection Agency (USEPA) has classified 2,3,7,8-tetrachloro-p-dioxin (TCDD) as a probable human carcinogen; subsequently, sources of TCDD in the environment have been regulated on the basis of animal cancer rates extrapolated to doses associated with human exposures. Two major activities have prompted the decision to reassess this approach for evaluating TCDD toxicity and its associated risks. First, an epidemiological study of cancer mortality in U.S. chemical workers by the National Institute of Occupational Safety and Health provided evidence of TCDD-mediated human carcinogenicity (Fingerhut et al. 1991 ). Second, at a 1990 Banbury conference a consensus …


Using Biodiversity Data To Assess Species--Habitat Relationships In Glacier National Park, Montana, Diane M. Debinski, Peter F. Brussard Nov 1994

Using Biodiversity Data To Assess Species--Habitat Relationships In Glacier National Park, Montana, Diane M. Debinski, Peter F. Brussard

Diane M. Debinski

Biodiversity surveys are becoming increasingly popular. However, standard analysis techniques for these data have not yet been developed. This paper explores the use of multivariate ordination techniques for assessing species—habitat relationships using biodiversity data. The research was conducted in Glacier National Park, Montana, and birds and butterflies were chosen as the taxonomic groups of study. Biodiversity assessment sites were established throughout a range of habitats and monitored from 1987 through 1989. Presence/absence sampling over the total number of sampling sites was used to classify species commonness and rarity. Approximately 86% of the historically recorded butterflies and 70% of the historically …


Interim Report On Data And Methods For Assessment Of 2,3,7,8-Tetrachlorodibenzo-P-Dioxin Risks To Aquatic Life And Associated Wildlife, Steven P. Bradbury, Philip M. Cook, Russell J. Erickson, Robert L. Spehar, Gerald T. Ankney Mar 1993

Interim Report On Data And Methods For Assessment Of 2,3,7,8-Tetrachlorodibenzo-P-Dioxin Risks To Aquatic Life And Associated Wildlife, Steven P. Bradbury, Philip M. Cook, Russell J. Erickson, Robert L. Spehar, Gerald T. Ankney

Steven P. Bradbury

In April, 1991 the Administrator of the U.S. Environmental Protection Agency (EPA) announced that the Agency would conduct a scientific reassessment of the risk of 2,3,7,8-tetrachlorodibenzo-p-dioxin (hereafter referred to as TCDD), and similar chemicals, to human health and the environment. Since 1985, EPA has classified TCDD, which it considers the most potent known animal carcinogen, as a probable human carcinogen. Sources of TCDD in the environment were subsequently regulated on the basis of animal cancer rates extrapolated to doses associated with human exposures. Recently, consensus has developed that the toxic effects of TCDD appear to be mediated by its binding …


Hepatic Microsomal N-Hydroxylation Of Aniline And 4-Chloroaniline By Rainbow Trout (Onchorhyncus Mykiss), Steven P. Bradbury, J. M. Dady, A. D. Hoffman, M. M. Voit, D. L. Olson Dec 1991

Hepatic Microsomal N-Hydroxylation Of Aniline And 4-Chloroaniline By Rainbow Trout (Onchorhyncus Mykiss), Steven P. Bradbury, J. M. Dady, A. D. Hoffman, M. M. Voit, D. L. Olson

Steven P. Bradbury

N-Hydroxylation of aniline and 4-chloroaniline was quantified in rainbow trout microsomal preparations using h.p.l.c.-liquid scintillation methods. Radioactive phenylhydroxylamine and 4-chlorophenylhydroxylamine metabolites were identified by co-elution with non-labelled standards. The method provided resolution of metabolite standards, and quantification of both N-hydroxylated metabolites was achieved without derivatization. The maximum velocities at 25 degrees C were 33.8 +/- 1.40 and 22.0 +/- 0.98 pmol/min per mg for aniline and 4-chloroaniline N-hydroxylation, respectively. The Km values were 1.0 +/- 0.11 and 0.8 +/- 0.11 mM for aniline and 4-chloroaniline N-hydroxylation, respectively. These activities were not induced by treatment of the trout with Aroclor 1254 …


Behavior And Ecological Interactions Of Larval Odonata, Clay L. Pierce, Philip H. Crowley, Dan M. Johnson Oct 1985

Behavior And Ecological Interactions Of Larval Odonata, Clay L. Pierce, Philip H. Crowley, Dan M. Johnson

Clay L. Pierce

Enallagma aspersum and E. traviatum (Odonata: Coenagrionidae) are the most abundant larval odonates in Bays Mountain Park (Sullivan County, Tennessee, USA), although their spatial distributions are essentially nonoverlapping. E. traviatum coexists with insectivorous fish in a small lake, whereas E. aspersum is restricted to a small fishless pond nearby. Behavioral observations revealed that E. aspersum larvae were more active than E. traviatum, and tended to occupy more conspicuous positions. E. aspersum also engaged in more confrontations than E. traviatum, especially at higher density. In laboratorye xperimentsw ith juvenile bluegills( Lepomism acrochirusa) s predators,E . aspersum larvae were more vulnerable to …