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Full-Text Articles in Life Sciences

Brook Trout Enhancement Through Rainbow Trout Removal By Electroshocking In The Great Smoky Mountains National Park, Jeanne Dyanne Riley Aug 1986

Brook Trout Enhancement Through Rainbow Trout Removal By Electroshocking In The Great Smoky Mountains National Park, Jeanne Dyanne Riley

Masters Theses

Brook trout ( Salvelinus fontinalis) populations have declined in the Great Smoky Mountains National Park since the early 1900's. The continuing range loss of the Parks' only native trout species has been attributed mainly to the introduced rainbow trout ( Salmo gairdneri ) . Past studies have indicated that removal of introduced trout by electroshocking results in the enhancement of brook trout populations.

Twelve study streams in the Park were grouped as control and treatment streams. Removal efforts of one, two, and three passes consecutively were conducted on treatment streams to determine the effort needed to control rainbow trout populations. …


Systematics, Distribution, And Biology Of Fishes Currently Allocated To Erimystax (Jordan), A Subgenus Of Hybopsis (Cyprinidae), John Lowrey Harris Aug 1986

Systematics, Distribution, And Biology Of Fishes Currently Allocated To Erimystax (Jordan), A Subgenus Of Hybopsis (Cyprinidae), John Lowrey Harris

Doctoral Dissertations

Intra- and interspecific variation of species of the subgenus Erimystax, genus Hybopsis, are analyzed using multivariate statistical techniques. Diagnoses, descriptions, figures, supporting tables, and distribution maps are provided to facilitate identification of the subgenus and component species. Results of multivariate analyses support the elevation of the Ozark subspecies of Hybopsis dissimilis to specific standing as Hybopsis i. insignis distributed in the lower Tennessee and Cumberland river drainages and H. insignis eristigma found in eastern tributaries of the upper Tennessee River drainage. Populations interpreted as intergrades occur in the Clinch, Powell, and Holston rivers. Two subspecies of Hybopsis x-punctata are recognized …


Between Population Comparison Of Resource Acquisition In The Long Jawed Orb Weaving Spider Tetragnatha Elongata, Rosemary Grace Gillespie Jun 1986

Between Population Comparison Of Resource Acquisition In The Long Jawed Orb Weaving Spider Tetragnatha Elongata, Rosemary Grace Gillespie

Doctoral Dissertations

Behavioral adaptations for resource acquisition in the long jawed orb weaving spider Tetragnatha elongata Walckenaer (Araneae: Tetragnathidae) are documented in this study. It examines the form and mechanism of spider foraging behavior, an essential prerequisite to the realization of the commercial use of spiders in integrated pes t management. Being the most common and ubiquitous of insect predators, spiders offer tremendous potential as stabilizers in agro ecosystems with unstable cycling of phytophagous insects. The initial part of this study examines the mechanisms employed by T. elongata in selecting a habitat, and demonstrates that spiders do not build webs where the …


Comparative Bioavailability Of Sediment-Sorbed Hexachlorobiphenyl, C. Michael Swindoll Jun 1986

Comparative Bioavailability Of Sediment-Sorbed Hexachlorobiphenyl, C. Michael Swindoll

Doctoral Dissertations

The bioavailability of sediment-sorbed hexachlorobiphenyl (HCB) to bacteria, midge larvae (Chironomus tentans), and mosquitofish (Gambusia affinis) was examined in order to elucidate the influence of abiotic and biotic factors on the bioaccumulation process. Factors examined included sediment type, sediment organic matter, HCB concentration, temperature, and biological viability. Additional experiments were conducted to evaluate the relative role of sediment and dietary HCB sources to the accumulation of HCB in mosquitofish.

In general, the bioavailability of sediment-sorbed HCB was inversely related to the surface area and the organic content of the sediment. The organic content of the sediment …


Vulnerability Of Cougars To Hunting, Dan Barnhurst May 1986

Vulnerability Of Cougars To Hunting, Dan Barnhurst

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Forty radio-collared cougars (Felis concolor) were monitored for 630 cougar months. Track searches were conducted and tracking information was gathered over a 20-month period. Vulnerability was estimated to be greatest for 0 to 6-month-old kittens. This age class is the most susceptible to starvation after being orphaned, or being killed by hounds when the hunter is unaware of their presence, since their tracks were found with their mother's tracks only 19 percent of the time. Tracks of 7 to 12-month old kittens were found with their mother's tracks 43 percent of the time. Relative road-crossing frequencies of seven …


Manganese Toxicity In Mice: Evaluation Of Neruochemical And Immunologial Alteration, Benjamart Srisuchart May 1986

Manganese Toxicity In Mice: Evaluation Of Neruochemical And Immunologial Alteration, Benjamart Srisuchart

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Neurochemical and immunological effects of manganese chloride (MnCl2) were evaluated using young male CD-1 mice as the animal model. Intraperitoneal (i.p.) injection of MnCl2 (1, 3 and 10 mg/kg) daily for 4 weeks did not produce mortality or overt signs of toxicity in any of the treated animals. Manganese treatment increased the thymidine uptake of cultured splenic cells and the selective lymphoproliferative response to T-cell mitogens, phytohaemagglutinin and concanavalin A, in all the treated groups. No difference in the response to B-cell mitogen, lipopolysaccharide was observed. A dose of 10 mg/kg MnCl2 increased the mixed lymphocyte …


Effect Of Spring Grazing By Cattle On Growth And Survival Of Shrub Seedlings Interplanted In Crested Wheatgrass, Lynn M. Mcconville May 1986

Effect Of Spring Grazing By Cattle On Growth And Survival Of Shrub Seedlings Interplanted In Crested Wheatgrass, Lynn M. Mcconville

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A short duration-high intensity grazing trial was conducted in spring of 1985 to determine whether shrub establishment in crested wheatgrass pastures could be enhanced through spring grazing by cattle, or by fertilization of shrub seedlings. Data was collected on diet selection by cattle during spring grazing, and on subsequent shrub growth and survival. Shrubs studied were transplants of sagebrush, Artemisia tridentata, fourwing saltbush, Atriplex canescens, bitterbrush, Purshia tridentata, and one year old bitterbrush seedlings.

Cattle did not browse sagebrush or fourwing saltbush transplants, but utilization of bitterbrush transplants and seedlings averaged 15 and 42 percent, respectively. Shrub …


Factors Affecting Puberty, Estrus And Ovulation In Corriedale And Criollo Sheep Of The Southern Peruvian Highlands, Pedro Walter Bravo Matheus May 1986

Factors Affecting Puberty, Estrus And Ovulation In Corriedale And Criollo Sheep Of The Southern Peruvian Highlands, Pedro Walter Bravo Matheus

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research was conducted at the La Raya experiment station, Cusco, Peru (4200 m elevation, 15°S latitude, and 70 °W longitude) using 60 Corriedale, and 60 Criollo ewes during three consecutive years (April 1981 - March 1984). Age, and weight at puberty, age at physical maturity, and the effects of breed, age (physically immature and mature), year, and month were measured on body weight, incidence of estrus, and incidence and rate of ovulation. There was a significant difference (P<.05) among breed, year, and the interactions for body weight at puberty. The mean age at puberty for 1982-83 was 693.6 days (23.1 months) for Corriedale and 483.3 days (16.1 months) for Criollo. The mean liveweight at puberty was 27.2 kg for Corriedale, and 25.3 kg for Criollo. Corriedale ewe lambs weighed more than Criollo, attained puberty seven months later than Criollo. At comparable age (15-17 months) at the Southern Peruvian Highlands 100 % of the Criollo reached puberty, compared to 58% of the Corriedale. Body weight, incidence of estrus and ovulation were affected (P<.01) by breed, age, year, month, and their interactions. Physical maturity was attained at 39 and 36 months of age for Corriedale, and Criollo, respectively. Weight changes during the year were associated with feed availability. The mean overall incidence of estrus was 45.4 % for Corriedale (43.6 in physically immature, and 47.2 % in mature ewes), and 67.1 % for Criollo ewes (66.3, in physically immature, and 68.7 % in mature ewes). The mean overall incidence of ovulation was 39.6 % for Corriedale (39.7, in physically immature, and 39.5 % in mature ewes), and 58.5 % for Criollo ewes (59.4, in physically immature and 56.7 % in mature ewes). Both breeds demonstrated seasonality of estrus and ovulation with the Corriedale being shorter than the Criollo. The incidence of ovulation in both breeds was less than that of estrus. The ovulation rate was 1.00 for Corriedale, and 1.03 for Criollo (P>.05). Even though Criollo ewes weighed less than Corriedale, they attained puberty earlier, and showed less seasonality in estrus and ovulated …


Aspects Of The Feeding Ecology Of The Bonneville Cisco Of Bear Lake, Utah-Idaho, David C. Lentz May 1986

Aspects Of The Feeding Ecology Of The Bonneville Cisco Of Bear Lake, Utah-Idaho, David C. Lentz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Bonneville cisco (Prospium gemmiferum), a small planktivorous whitefish, is an important part of the distinctive fish community of Bear Lake, Utah-Idaho. The Bonneville cisco plays a key role in the trophic structure by converting zooplankton to fish biomass and providing a major forage source for cutthroat and lake trout. Aspects of cisco feeding ecology studied include characterization of the zooplankton community composition and dynamics and cisco feeding habits and prey selection.

Composition and seasonal dynamics of the zooplankton community were determined for a fifteen month period during 1981-1982. The community was dominated by a calanoid copepod, Epischura …


The Diet Of The Gopher Tortoise, Gopherus Polyphemus, In A Sandhill Habitat In Central Florida, Laurie Ann Macdonald Apr 1986

The Diet Of The Gopher Tortoise, Gopherus Polyphemus, In A Sandhill Habitat In Central Florida, Laurie Ann Macdonald

USF Tampa Graduate Theses and Dissertations

Scat analysis and foraging observations were used to determine the diet of a gopher tortoise, Gopherus polyphemus, population in a sandhill community in west central Florida. Live vegetation was assessed to determine plant availability. The bulk of the gopher tortoise diet was composed of the dominant plant species in the habitat while the tortoises were selective with respect to most plant genera. Tortoises ingested many plant taxa with Poaceae, Asteraceae, Fabaceae, Pinaceae and Fagaceae being the most frequent components of the diet. Sixty-eight genera from 26 families were identified in the tortoise diet. In the scat the most common …


Implanting Effects On Performance, Carcass Characteristics And Reproductive Parameters In Intact Beef Males, Shirley J. Gordon Jan 1986

Implanting Effects On Performance, Carcass Characteristics And Reproductive Parameters In Intact Beef Males, Shirley J. Gordon

Electronic Theses and Dissertations

The research presented herein was designed to determine the effects of post-weaning implanting on performance, carcass characteristics, hormonal profile and reproductive parameters.


Nutritional Factors Modifying Fatty Liver Hemorrhagic Syndrome In Caged Laying Hens, Chandi C. Rakshit Jan 1986

Nutritional Factors Modifying Fatty Liver Hemorrhagic Syndrome In Caged Laying Hens, Chandi C. Rakshit

Electronic Theses and Dissertations

Three experiments each with two phases were conducted to study the effect of different levels of distillers dried grain (DDG), fat, oats and a mixture of oats and DDG on Fatty Liver Hemorrhagic Syndrome (FLHS) in caged laying hens. The second phase of each experiment was conducted by force-feeding the same diets used in the first phase at 120% of their normal intakes. This produces FLHS and thereby permits studying the effect of diets. During the force-feeding period of the third experiment, serum estradiol levels of hens from each treatment and each type of feeding were measured to study the …


A Review Of The Management And Current Status Of Northern Fur Seals Of The Pribilof Islands, Holly Hansell Jan 1986

A Review Of The Management And Current Status Of Northern Fur Seals Of The Pribilof Islands, Holly Hansell

Theses and Major Papers

The North pacific fur seals of Alaska's Pribilof Islands have been subjected to commercial harvest for nearly 200 years. The harvest has been regulated under international agreement almost continuously since 1911; first under the 1911 North Pacific Fur Seal Convention, and following that under the 1957 Interim Convention on Conservation of North Pacific Fur Seals. Both Conventions banned pelagic sealing and divided the restricted land harvest among the four member states, the United States, Canada, Japan, and the Soviet Union. Management under the 1911 convention resulted in a steady increase in the severely depleted fur seal herd, restoring the population …


The Development Of The Shrimp Mariculture Industry In Ecuador And Its Impact On The U.S. Market, Richard A. Norton Jan 1986

The Development Of The Shrimp Mariculture Industry In Ecuador And Its Impact On The U.S. Market, Richard A. Norton

Theses and Major Papers

The demand for tropical shrimp is increasing at a much higher rate than other fish and seafood commodities. With this increase in demand, there has been enormous interest to expand global shrimp production. Mariculture, the term used to describe the practice of farming animal and/or plant life from the sea, has created new opportunities and problems for the future of the global shrimp industry. Since shrimp is considered a high-value food commodity, the development has drawn interest from many United States and European investors. One country in particular, Ecuador, which will be the focus of this discussion, has exemplified many …


Investment Opportunities In The Nigerian Fishing Industry, Ayotunde M. Giwa Jan 1986

Investment Opportunities In The Nigerian Fishing Industry, Ayotunde M. Giwa

Theses and Major Papers

The major problem facing the Nigerian fishing industry is in its inability to satisfy the demand for tasty yet inexpensive animal protein. Nigeria's marine biological resources are limited and the Gulf of Guinea is among the poorest in the whole of West Africa. Nigeria's population is estimated to have reached about 100 million and is growing at 3.09 per cent per annum. Nigeria's fishing industry is multi-sectoral and composed of the riverine, lake, coastal, estuarine, and culture fisheries. Together they constituted about 1.5 per cent of the GDP in 1976. Up to the present moment, the National has relied on …


Satellite Remote Sensing And Fisheries Applications, Holly M. Turton Jan 1986

Satellite Remote Sensing And Fisheries Applications, Holly M. Turton

Theses and Major Papers

Satellite remote sensing has the capacity to aid the three major components of a fishery: research, management, and the fishing industry. An evaluation of the potential of satellite-derived data to the fishery is based upon six case studies which are presented as evidence of the capabilities of satellite-borne sensors. Peripheral applications pertaining to the marine environment and possible applications for the future are reviewed. Three basic categories of remote sensing programs related to the fishery are defined: one to test the applicability of the technology to the field of fisheries; another to employ the technology to fisheries research; and a …


A Comparison Of High-Performance Short-Duration And Repeated-Seasonal Grazing Systems, Jerry David Volesky Jan 1986

A Comparison Of High-Performance Short-Duration And Repeated-Seasonal Grazing Systems, Jerry David Volesky

Electronic Theses and Dissertations

Six replications of l-herd 16-subunit High-Performance Short-Duration (HPSDG) and Repeated-Seasonal (RSG) (May-Sep.) grazing system treatments were compared during 1983 and 1984 at the Cottonwood Range and Livestock Research Station located in western South Dakota. Calves and lambs were allotted to the experimental pastures in sets approximately equal on an animal unit basis. Animal numbers were adjusted with put-and-take sets to attain planned forage levels for each cycle of rotation in HPSDG and comparable end of season forage use levels in both treatments. The HPSDG system was operated with four cycles of rotation that had 1, 2, 2 and 3 occupation …


Inhibition Of Psychrotrophic Bacterial Growth In Refrigerated Milk By Addition Of Carbon Dioxide, Robert Francis Roberts Jan 1986

Inhibition Of Psychrotrophic Bacterial Growth In Refrigerated Milk By Addition Of Carbon Dioxide, Robert Francis Roberts

Electronic Theses and Dissertations

The advent of on-farm refrigerated storage for raw milk in the late 1940's and its subsequent adoption by North American dairyman 'during the next 20 years essentially eliminated spoilage of milk by lactic acid bacteria. However, refrigeration does not prevent growth of all microorganisms present in raw milk (9, 33, 51, 52, 54, 55). Many microorganisms capable of growth at refrigeration temperatures, termed psychrotrophic bacteria, are present as normal contaminants in raw milk supplies. For purposes of clarity, psychrotrophic microorganisms have been defined as microorganisms capable of growth at 7°C or below regardless of their optimum growth temperature (9). Milk …


Ectoparasites Of Geomys Bursarius Illinoensis, Rick L. Miller Jan 1986

Ectoparasites Of Geomys Bursarius Illinoensis, Rick L. Miller

Masters Theses

This study was conducted to determine what ectoparasitic organisms are found on the pairie pocket gophers, Geomys burasrius, occurring in an isolated population in northeastern Illinois. The study area was a five hectare grassland community composed predominately of sandy soil, located in northeastern Iriquois Co., two miles north and three miles east of Beaverville, IL.

A total of 19 pocket gophers were captured from October 2 to November 17, 1983. Blood was collected and smears were made in the field. Hosts were examined for ectoparasites in the laboratory. Six hundred and nine ectoparasitic organisms were isolated representing a mean …


An Analysis Of Waterfowl Hunter Activity And Harvest On Selected Public Hunting Areas In Illinois, Gary E. Potts Jan 1986

An Analysis Of Waterfowl Hunter Activity And Harvest On Selected Public Hunting Areas In Illinois, Gary E. Potts

Masters Theses

Hunter activity and waterfowl harvest were studied on 11 public waterfowl hunting areas (PHA) in Illinois which utilized 1, 2, or 3-year duck blind allocation systems from 1979-1983. The number of individual hunters, man-days, and average man-days hunted per season varied for each area in each year. The average man-days hunted per season for all study areas was 5.7 with a range of 4.4 to 6.4. Highly significant correlations existed between blind-days and man-days (r=.99), blind-days and man-hours (r=.97), and man-days and man-hours (r=.98) suggesting that the three variables are equally valid for evaluating hunter activity. On 1-year duck blind …


Reproductive Ecology, Population Dynamics And Seasonal Movements Of The Hogchoker (Trinectes Maculatus), In The Elizabeth River, Virginia, Stephen M. Smith Jan 1986

Reproductive Ecology, Population Dynamics And Seasonal Movements Of The Hogchoker (Trinectes Maculatus), In The Elizabeth River, Virginia, Stephen M. Smith

Dissertations, Theses, and Masters Projects

No abstract provided.


The Use Of Crab Meal As A Supplemental Food For Juvenile Hard Clams (Mercenaria Mercenaria), Patricia Lynn Duncan Jan 1986

The Use Of Crab Meal As A Supplemental Food For Juvenile Hard Clams (Mercenaria Mercenaria), Patricia Lynn Duncan

Dissertations, Theses, and Masters Projects

No abstract provided.


Biological Review And Commercial Whelk Fisheries Analysis Of Busycon Carica With Comments On B Canaliculatum And B Contrarium In Virginia, Jane Dicosimo Jan 1986

Biological Review And Commercial Whelk Fisheries Analysis Of Busycon Carica With Comments On B Canaliculatum And B Contrarium In Virginia, Jane Dicosimo

Dissertations, Theses, and Masters Projects

No abstract provided.


Factors Affecting The Predator-Prey Relationship Between Predaceous Diving Beetle Larvae (Dytiscus Fasciventris) And Two Anuran Tadpole Species (Bufo Americanus And Hyla Crucifer), Todd S. Campbell Jan 1986

Factors Affecting The Predator-Prey Relationship Between Predaceous Diving Beetle Larvae (Dytiscus Fasciventris) And Two Anuran Tadpole Species (Bufo Americanus And Hyla Crucifer), Todd S. Campbell

Masters Theses

It has previously been demonstrated that American toad (Bufo americanus) tadpoles are more vulnerable to predation by diving beetle larvae (Dytiscus fasciventris) than are spring peeper (Hyla crucifer) tadpoles. A laboratory study was undertaken to further delineate factors that contribute to the differential vulnerability observed. Beetle larvae are more effective tadpole predators in shallow, than in deep, water and appear to prefer to adopt a "sit-and-wait" predator strategy while clinging to emergent vegetation. Depth preference experiments in the laboratory indicated that both tadpole species prefer deep areas to shallow areas irrespective of whether a …


Effects Of Dominance/Subordination, Encounter Site And Olfactory Cues On Behavior And Spatial Dynamics Of Male Peromyscus Leucopus Noveboracensis, Janet L. Norcross Jan 1986

Effects Of Dominance/Subordination, Encounter Site And Olfactory Cues On Behavior And Spatial Dynamics Of Male Peromyscus Leucopus Noveboracensis, Janet L. Norcross

Dissertations, Theses, and Masters Projects

No abstract provided.


Lactational And Systemic Responses To The Supplementation Of Protected Methionine In Soybean Meal Diets, Daniel J. Illg Jan 1986

Lactational And Systemic Responses To The Supplementation Of Protected Methionine In Soybean Meal Diets, Daniel J. Illg

Electronic Theses and Dissertations

The high producing dairy cow requires a complex balance of protein and energy. Microbial protein provides a substantial amount of the amino acids absorbed by the small intestine. High production rates cannot be attained with microbial protein as .the sole source of amino acids. The ten classical essential amino acids are required for milk protein synthesis. Increasing the amount of available amino acids to the mammary gland has improved casein production, indicating substrate availability as a controlling factor to milk protein synthesis. A major portion of the nitrogen component of milk is derived from free plasma amino acids. Uptake by …


The Feeding Ecology Of The Chesapeake Bay Ospreys And The Growth And Behavior Of Their Young, Peter Kleppinger Mclean Jan 1986

The Feeding Ecology Of The Chesapeake Bay Ospreys And The Growth And Behavior Of Their Young, Peter Kleppinger Mclean

Dissertations, Theses, and Masters Projects

No abstract provided.


Barn Owl Habitat And Prey Use In Agricultural Eastern Virginia, Charles Patrick Rosenburg Jan 1986

Barn Owl Habitat And Prey Use In Agricultural Eastern Virginia, Charles Patrick Rosenburg

Dissertations, Theses, and Masters Projects

No abstract provided.


Forage Utilization Estimated By Height-Weight And Grazed-Plant Methods, Joann Clark Jan 1986

Forage Utilization Estimated By Height-Weight And Grazed-Plant Methods, Joann Clark

Undergraduate Honors Capstone Projects

Determining utilization has been one of the most difficult tasks required of range scientists down through the years (Pieper 1973). Utilization is defined as the portion of the current year's growth of the plant that the animal consumes or destroys. For this reason it is difficult to measure utilization because you are trying to measure something that no longer exists.

Numerous methods have been developed for determining utilization. Some methods are rapid while others are more detailed and time consuming, but may give greater accuracy.

This study was done to see how well utilization estimates made by the grazed-plant method …


The Role Of Plant Hormones In Grass Tiller Development, Marit Snow Jan 1986

The Role Of Plant Hormones In Grass Tiller Development, Marit Snow

Undergraduate Honors Capstone Projects

Two bunchgrass species commonly found in the Intermountain West, Agropyron spicatum and A. desertorum, are morphologically similar but respond to defoliation very differently. A. desertorum produces more daughter tillers and is more hardy than A. spicatum. Hormones were applied to experimental plants to observe changes in tillering rates, growth rates, and response of plants to the stress of exogenous hormone application. Gibberellic acid treatments were related to increased tiller height in both species, but also a decrease in daughter tiller production in A. desertorum and an increase in senescence in A. spicatum. Kinetin increased senescence in A. desertorum. Auxin showed …