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The Effects Of Photoperiod And Melatonin Injections On The Reproductive System Of Pinealectomized Male Mice Mus Musculus, Icr Strain, John Earnest Constantine Aug 1981

The Effects Of Photoperiod And Melatonin Injections On The Reproductive System Of Pinealectomized Male Mice Mus Musculus, Icr Strain, John Earnest Constantine

Master's Theses

One hundred two male mice , Mus musculus, ICR strain, age four weeks, were obtained. Fifty-one mice were pinealectomized and 51 were sham operated. The animals were divided into three photoperiod groups: 1.5L:22.5D, 14L:10D, 24L; 0D. The mice were subcutaneously injected daily with 10 ug melatonin or control solution from post-operative day J to post-operative day 60, On post-operative day 60 representatives of each photo­ period-surgery-injection regimen were paired with females. The remaining animals were killed and several organs were removed and weighed, Melatonin injections were progonadal in pinealectomized mice and inhibitory in sham mice in several instances. Histological examination …


Population Structure And Reproduction In The Introduced Florida Population Of The Pike Killifish, Belonesox Belizanus (Pisces: Poeciliidae), James S. Turner Jul 1981

Population Structure And Reproduction In The Introduced Florida Population Of The Pike Killifish, Belonesox Belizanus (Pisces: Poeciliidae), James S. Turner

Retrospective Theses and Dissertations

The pike killifish, Belonesox belizanus Kner, is the largest member of the live-bearing family Poeciliidae. The species is native to Central America, and was introduced into Dade County, Florida in 1957. B. belizanus is primarily piscivorous, and has been identified as a potential ecological "problem" species for Florida due to its heavy predation on small native fishes, especially the mosquitofish (Gambusia affinis). The population structure and reproduction of the Florida population were investigated in this study from field samples and aquarium observations. The mean standard length (SL) of mature females was about 103 mm. Most females larger than 75 mm …


A Morphometrical Analysis Of The Guinea Pig Placenta After Chronic Exposure To Carbon Monoxide, Marcella J. Woolsey Jun 1981

A Morphometrical Analysis Of The Guinea Pig Placenta After Chronic Exposure To Carbon Monoxide, Marcella J. Woolsey

Loma Linda University Electronic Theses, Dissertations & Projects

We used morphometric analysis to determine if placental structure is modified by carbon monoxide, Camm-Hartley guinea pigs were exposed throughout gestation to chronic conditions of carbon monoxide (averaging about 180 parts per million). Maternal weight, placental weight, fetal weight, and fetal length were recorded at the time of placental fixation. Using a computerized image analyzer on photomicrographs obtained through light microscopy, we measured maternal and fetal percent vessel volumes, surface areas, and vessel numbers. Maternal vessel numbers and surface area remained basically unchanged but decreased slightly. Maternal percent volume decreased 15%. However, fetal capillary number increased 35% (p < 0.01) from a control value of 2325 ± 184 per mm2 (SE …


The Effects Of Denervation On Caudal Fin Regeneration In The Goldfish, Carassius Auratus (Linnaeus), Janet Rowlett May 1981

The Effects Of Denervation On Caudal Fin Regeneration In The Goldfish, Carassius Auratus (Linnaeus), Janet Rowlett

Masters Theses & Specialist Projects

Goldfish of the wild-strain variety, Carassius auratus, were used in the study of caudal fin regeneration. The purpose of this study was to determine the effects of denervation on caudal fin regeneration.

In the experimental groups, it was evident that denervation did not prevent regeneration, although it was significantly reduced. Statistical analysis using the Duncan's Multiple Range Test showed a highly significant difference (0.01 % level) in the mean percentage of regeneration between the denerved group and the other three groups.

Caudal fins having proximal amputations regenerated at a faster rate than those having distal amputations, producing a higher …


Population Stability Of Three Species Of Zooplankton In Westhampton Lake, Richmond, Virginia, James Christopher Conyers May 1981

Population Stability Of Three Species Of Zooplankton In Westhampton Lake, Richmond, Virginia, James Christopher Conyers

Master's Theses

Populations of zooplankton, Keratella cochlea's (Rotifera) Bosmina longirostris (Cladocera), and Mesocyclopsedax (Copepoda) were sampled in Westhampton Lake from June 30 to December 22, 1978. Population densities were estimated over time and analyzed for stability relative to the occurrence of rainfall. Two aspects of stability were used for analysis and given operational definitions as follows: Resistance - a population was resistant if its density was not more variable during periods of rain compared with periods of little or no rain; Persistence - a population was persistent if its density during periods of rain was not different from its density in periods …


Vegetation Responses To Prescribed Burning In A Mixed-Conifer Woodland, Cuyamaca Rancho State Park, California, Bradford D. Martin May 1981

Vegetation Responses To Prescribed Burning In A Mixed-Conifer Woodland, Cuyamaca Rancho State Park, California, Bradford D. Martin

Loma Linda University Electronic Theses, Dissertations & Projects

This study reports the results of light intensity prescribed burning on the vegetation of 3 jeffrey pine-black oak woodland sites in Cuyamaca Rancho State Park, California. The 1.2 ha, 85 ha, and 6 ha burn plots were measured for tree and shrub density and basal area 6 months, 1% years, and 2 years following burning for the 3 sites respectively. Each burn site measured was compared against equivalent unburned control plots to help assess the effects of the burning. Density of saplings, seedlings, and herbaceous vegetation was also determined for the woodland understories. Dominance and relative dominance of herbaceous ground …


Biphenyl Hydroxylation By Vole Hepatic Microsomes, Moheb H. Makary May 1981

Biphenyl Hydroxylation By Vole Hepatic Microsomes, Moheb H. Makary

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Metabolism of biphenyl by meadow voles (Microtus montanus) liver microsomes was studied by gas liquid chromatography. The microsomal biphenyl hydroxylation of Swiss Webster mice (outbred) was also investigated to provide a species comparison. 4-hydroxybiphenyl (major metabolite), 3-hydroxy biphenyl (minor) and smaller amounts of 2-hydroxybiphenyl were identified as metabolites of biphenyl incubated with vole liver microsomes. Liver microsomes from Swiss mice formed 4-hydroxy biphenyl (major metabolite) and almost equal amounts of 2- and 3-hydroxy biphenyl (minor metabolite). The amount of the hydroxy biphenyls formed by vole liver microsomes was considerably less per milligram of microsomal protein than for mice. …


The Hatching And Emergence Of Loggerhead Turtle (Caretta Caretta) Hatchlings, Richard J. Demmer Apr 1981

The Hatching And Emergence Of Loggerhead Turtle (Caretta Caretta) Hatchlings, Richard J. Demmer

Retrospective Theses and Dissertations

Loggerhead turtle (Caretta caretta) eggs were collected at the time of laying during the summer of 1977 on the beaches of Canaveral National Seashore and the Merritt Island National Wildlife Refuge in Brevard County, Florida. The eggs were placed in land-lines buckets and maintained at ambient temperature in a house trailer hatchery. After 50 to 55 days of incubation whole or partial clutches were transferred to glass observation containers and covered to a depth of 20 cm. Hatching and emergence behavior were visually observed and activity was timed on an event recorder that was activated by four motion switches placed …


Nutrient Retention In Shallow Reservoirs Using Selected Aquatic Macrophytes, Phillip D. Sacco Apr 1981

Nutrient Retention In Shallow Reservoirs Using Selected Aquatic Macrophytes, Phillip D. Sacco

Retrospective Theses and Dissertations

A field experiment was conducted to evaluate the possibility of using shallow reservoirs containing aquatic plants to reduce excess nutrient levels of agricultural drainage effluent from organic soils. The reservoir systems consisted of three small reservoirs in series, containing separate stands of Eichhornia crassipes, Egeria densa and Typha sp., and a single large reservoir containing equal areas of all three aquatic plants. A control reservoir without plants was included. Drainage water from organic soils was pumped through each reservoir at 39.6 l/sec., 6 hours per day, 6 days per week. the major nutrients monitored in theses flow-through systems included nitrate-N, …


An Experimental Study Of Dispersal Of The Cotton Rat, Sigmodon Hispidus, Stephen R. Stafford Apr 1981

An Experimental Study Of Dispersal Of The Cotton Rat, Sigmodon Hispidus, Stephen R. Stafford

Retrospective Theses and Dissertations

Dispersal of cotton rats was examined over an annual cycle of abundance by removal trapping in pine flatwoods. All cotton rats live-trapped at biweekly intervals on two 0.49 ha grids were removed, whereas rats on an adjacent control grid were tagged an released alive on site. The null hypothesis was that dispersing cotton rats would represent a random sample of sex and weight (age) classes from source populations, e.g. the control grid. Likewise, it was assumed that dispersal rates would be proportional to numerical changes in abundance on the control grid. Dispersing animals were clearly most prevalent on the removal …


Zooplankton Abundance And Diversity In Spring Lake, Florida, 1973-1976, Barry D. Billets Apr 1981

Zooplankton Abundance And Diversity In Spring Lake, Florida, 1973-1976, Barry D. Billets

Retrospective Theses and Dissertations

Seasonal variation in zooplanton abundance and diversity in Spring Lake, Florida was studies between 1973 - 1976. This clear, sand bottom lake is considered among the most oligotrophic in central Florida. Sixty rotifer species, sixteen cladoceran species, and seven copepod species were collected during the three year study. Annual mean zooplanton abundances ranged between 70 individuals/l and 80 individuals/l. Rotifers were more abundant than either cladocerans or adult copepods. Rotifers and immature crustaceans comprised nearly 75% of the annual mean zooplankton abundance. There was no significant difference (P < 0.05) between years for the annual mean abundance of zooplankton. The monthly mean abundance of cladocerans and adult copepods was generally less than 5 individuals/l. The greater abundance of rotifers in comparison to other zooplankton was mainly responsible for the variation in the values of the Shannon and Simpson Indices. The monthly mean Shannon Index was usually between 3.0 and 4.0. Seasonal differences in zooplankton abundance were apparently due to water temperature and specific conductivity for the 1974 - 1975 and 1975 - 1976 study years. Shannon diversity was significantly correlated with dissolved oxygen for the 1973 - 1974 and 1974 - 1975 study years.


Food Habits Of Largemouth Bass, Micropterus Salmoides (Lacepede) And Spotted Bass, Micropterus Punctulatus (Rafinesque), From Beech Fork Reservoir, A New Impoundment In Wayne And Cabell Counties, West Virginia, Michael A. Arcuri Jan 1981

Food Habits Of Largemouth Bass, Micropterus Salmoides (Lacepede) And Spotted Bass, Micropterus Punctulatus (Rafinesque), From Beech Fork Reservoir, A New Impoundment In Wayne And Cabell Counties, West Virginia, Michael A. Arcuri

Theses, Dissertations and Capstones

A study was undertaken to determine the food habits of two game fishes, the largemouth bass Micropterus salmoides (Lacepede) and the spotted bass M. punctulatus (Rafinesque) in Beech Fork Reservoir shortly after its impoundment. A total of 171 largemouth bass and 95 spotted bass were collected from July 1978, through June 1979, and their stomach contents analyzed.

Largemouth bass fed primarily on fishes, particularly young-of-the-year bluegill. Aquatic and terrestrial invertebrates were also important food items, especially during the spring and fall . The dominant aquatic forms were chironomid larvae and pupae while the dominant terrestrial forms were adult dipterans.

Spotted …


Larval Specialization And Phenotypic Variation In Arctopsyche-Grandis (Trichoptera, Hydropsychidae), F. Richard Hauer, Jack Arthur Stanford Jan 1981

Larval Specialization And Phenotypic Variation In Arctopsyche-Grandis (Trichoptera, Hydropsychidae), F. Richard Hauer, Jack Arthur Stanford

Biological Sciences Faculty Publications

Life history, trophic dynamics, abundance, and microdistribution of Arctopsyche grandis (Banks) were investigated in the Flathead River Basin, Montana. Two morphologically and ecological distinct larvae (Type I, with a head stripe and Type II, without a head stripe) were found throughout the drainage except in lower order streams. Type II larvae grew more rapidly and attained a larger size in final instar than Type I larvae. In areas where A. grandis biomass was greatest, Type I larvae were >10 times as abundant as Type II larvae. Type II larvae selected microhabitats characterized by larger interstitial spaces; Type I larvae were …


Correlation Of Injected Amygdalin And Urinary Thiocyanate In Jax C57 Bl/Ksj Mice, Maria A. Manhardt Jan 1981

Correlation Of Injected Amygdalin And Urinary Thiocyanate In Jax C57 Bl/Ksj Mice, Maria A. Manhardt

Master's Theses

No abstract provided.


Attributes Of Dispersing Meadow Voles In Open-Grid Populations, Raymond D. Dueser, Marcia L. Wilson, Robert K. Rose Jan 1981

Attributes Of Dispersing Meadow Voles In Open-Grid Populations, Raymond D. Dueser, Marcia L. Wilson, Robert K. Rose

Biological Sciences Faculty Publications

Dispersal was investigated in two open-grid populations of meadow voles, Microtus pennsylvanicus (Ord, 1815) an central Virginia (U.S.A.) from November 1974 to April 1978. "Dispersal" was defined as immigration onto open, occupied population grids. Dispersers were distinguished from residents by weight at first capture. Individuals first captured at weights <30 g were classified as residents; those first captured at >30 g were classified as dispersers. Three independent lines of evidence support the validity of the 30-g criterion for recognizing dispersers in these vole populations. With frequent trapping and high trappability, particularly of young animals, this open-grid method of study offers two advantages in the study of dispersal. First, dispersers identified …


The Metabolic Cost Of Behavioral Thermoregulation Of Body Temperature In The Northern Alligator Lizard Gerrhonotus Coeruleus, And How It Affects The Classical Concept Of Eurythermality, James Dudley Campbell Jan 1981

The Metabolic Cost Of Behavioral Thermoregulation Of Body Temperature In The Northern Alligator Lizard Gerrhonotus Coeruleus, And How It Affects The Classical Concept Of Eurythermality, James Dudley Campbell

Dissertations and Theses

The effect of total metabolic cost expenditures on the precision of behavioral thermoregulation was investigated for the purportedly eurythermic Northern Alligator lizard (Gerrhonotus coeruleus). An operant apparatus was designed to test metabolic output at different heat reinforcement magnitudes. The mean TB reflected in each trial was positively correlated to the length of reinforcement. The shuttle rate during each trial was inversely correlated to the length of reinforcement. The standard deviation and total metabolic costs did not vary significantly between trials undertaken at the same ambient temperature. Eurythermality in G. coeruleus is caused by fluctuations in preferred body temperature and …


State Of Cytidine 3', 5' Cyclic Monophosphate (Cyclic Cmp) Research, Joseph E. Stone, Bruce E. Murphy Jan 1981

State Of Cytidine 3', 5' Cyclic Monophosphate (Cyclic Cmp) Research, Joseph E. Stone, Bruce E. Murphy

Journal of the Arkansas Academy of Science

No abstract provided.


Seasonal Metabolism Of The Sphaeriid Clam, Musculium Partumeium (Say), From A Permanent And A Temporary Pond, Carl M. Way, Daniel J. Hornbach, Albert J. Burky Jan 1981

Seasonal Metabolism Of The Sphaeriid Clam, Musculium Partumeium (Say), From A Permanent And A Temporary Pond, Carl M. Way, Daniel J. Hornbach, Albert J. Burky

Biology Faculty Publications

Seasonal metabolic rates were examined for the sphaeriid clam, Musculium partumeium (Say) from a permanent and a temporary pond. For the fall-born generation from the permanent pond and for the single generation from the temporary pond, metabolic rates peak during periods of greatest growth and reproduction. Metabolic rates were consistently higher for the permanent pond population. These rates for Musculium partumeium extend the available information on the family Sphaeriidae to the genus Musculium.


Growth Of Pisidium Casertanum (Poli) In West Central Ohio, Albert J. Burky, Daniel J. Hornbach, Carl M. Way Jan 1981

Growth Of Pisidium Casertanum (Poli) In West Central Ohio, Albert J. Burky, Daniel J. Hornbach, Carl M. Way

Biology Faculty Publications

Clarke (1973) states that Pisidium casertanum (Poli) is perhaps the most common species of Pisidium and is truly cosmopolitan, occurring throughout Eurasia, Africa, Australia, and South, Central and North America. Populations of these clams are reported in habitats ranging from ephemeral ponds to benthic zones of deep lakes. Our study describes Manuscript received 29 May 1979 and in revised form 25 July 1980 (#79-34). 2 Present address: Department of Biology, University of Virginia, Charlottesville, VA 22901. 3 Present address: Department of Zoology, Miami University, Oxford, OH 45056. 41 aspects of the life-cycle of P. casertanum in a spring-fed stream with …


Environmental Heterogeneity, Genetic-Polymorphism, And Reproductive Strategies, M. J. Mcleod, Daniel J. Hornbach, S. I. Guttman, C. M. Way, Albert J. Burky Jan 1981

Environmental Heterogeneity, Genetic-Polymorphism, And Reproductive Strategies, M. J. Mcleod, Daniel J. Hornbach, S. I. Guttman, C. M. Way, Albert J. Burky

Biology Faculty Publications

No abstract provided.


Population Dynamics Of Musculus Senhousia And Protothaca Staminea In Tomales Bay, California, David Mcclain Nelson Jan 1981

Population Dynamics Of Musculus Senhousia And Protothaca Staminea In Tomales Bay, California, David Mcclain Nelson

University of the Pacific Theses and Dissertations

The changes in population density, growth and biomass of two infaunal, sympatric, suspension-feeding bivalves, Musculus senhousia (Benson, 1842) and Protothaca staminea (Conrad, 1837), have been investigated over an eighteen month period in Tomales Bay, California. M. senhousia, a mussel, displays two basic spawning times, one of which occurs in late spring, while the second spawning takes place in late summer. M. staminea, a venerid, spawns once during late spring. The population density of the mussel ranged from 9,180 m-2 in early spring to 752 m-2 in the fall of 1976. M. staminea had a maximum density of 1,120 m- 2 …


Eye Movement Related Single-Unit Recording In The Nucleus Reticularis Tegmenti Pontis In The Alert Monkey, William Franklin Crandall Jr. Jan 1981

Eye Movement Related Single-Unit Recording In The Nucleus Reticularis Tegmenti Pontis In The Alert Monkey, William Franklin Crandall Jr.

University of the Pacific Theses and Dissertations

Nucleus Reticularis Tegmenti Pontis (NRTP) is a structure which lies in the mid-brain ventral to the oculomotor complex. Anatomical studies strongly implicate it in oculomotor function as most of its inputs and outputs are to systems previously shown to be intimately involved in eye movement generation--superior colliculus (SC) and cerebellum. These reports show an integrative structure with inputs and outputs distributed in a way well suited for performing relay and feedback tasks. Physiological data in the alert, trained monkey has been gathered in an attempt to characterize these neurons and to classify them in functional terms. Three monkeys were trained …


Courtship And Reproduction In The Bali Mynah, Leucopsar Rothschildi (Aves : Sturnidae), Ann Patterson Marshall Jan 1981

Courtship And Reproduction In The Bali Mynah, Leucopsar Rothschildi (Aves : Sturnidae), Ann Patterson Marshall

University of the Pacific Theses and Dissertations

Reproductive behavior of captive Bali Mynahs (Leucopsar rothschildi) was studied at the Smithsonian Institution's Conservation and Research Center, Front Royal, Virginia. Courtship and copulation are followed by egg-laying, then incubation, hatching, brooding and feeding, fledging, and feeding. Parents become aggressive toward their young at the start of a new reproductive period, marked by a renewal of courtship.

The female does the majority of the incubation, brooding, and feeding of the young, although the male participates as well. The male performs both the bobbing· display and the crest display more than the female does. During these displays, the crest is prominently …


The Effect Of Heparin On Growth Characteristics Of Transplanted Spontaneously Occurring C3h/Hej Mouse Mammary Tumor, Muhammed Saleh Abdullah Banaja Jan 1981

The Effect Of Heparin On Growth Characteristics Of Transplanted Spontaneously Occurring C3h/Hej Mouse Mammary Tumor, Muhammed Saleh Abdullah Banaja

University of the Pacific Theses and Dissertations

Mouse mammary tumor is a common form of cancer used for experimental purposes. It is relatively resistant to chemotherapy. This investigation is designed to test the effect of heparin, a naturally occurring anticoagulant, on tumor growth using a genetically uniform laboratory animal.


Plant Protection As A Consequence Of An Ant-Membracid Mutualism: Interactions On Goldenrod (Solidago Sp.), Frank J. Messina Jan 1981

Plant Protection As A Consequence Of An Ant-Membracid Mutualism: Interactions On Goldenrod (Solidago Sp.), Frank J. Messina

Biology Faculty Publications

In central New York, two chrysomelid beetles, Trirhabda virgata and T. borealis, frequently cause severe defoliation of tall goldenrod, Solidago altissima. This plant is also the primary host of Publilia concava (Membracidae), a sap—feeding treehopper that is tended by ants, especially Formica spp. Staged encounters indicate that Formica ants attack adult Trirhabda beetles on goldenrod stems bearing membracids. Such stems escape defoliation by Trirhabda, and show greater mean height increment and seed production than their nearest neighbors without ants. The degree of plant protection depends on the duration of Formica presence. During Trirhabda outbreaks, only stems bearing Formica ants for …


Chemotherapeutic Effects Of The Extracts Of Allium Cepa And Allium Sativum On Infectivity Of Tobacco Mosaic Virus, Min-Lan Chang Jan 1981

Chemotherapeutic Effects Of The Extracts Of Allium Cepa And Allium Sativum On Infectivity Of Tobacco Mosaic Virus, Min-Lan Chang

Master's Theses

No abstract provided.


A Species Diversity Study Of The Benthic Population Of Cedar Lake, Illinois, Noreen L. Connolly Jan 1981

A Species Diversity Study Of The Benthic Population Of Cedar Lake, Illinois, Noreen L. Connolly

Master's Theses

No abstract provided.


Microelectrophoretic Separation Of Isozymes In Relation To Aging In The Hydroids Campanularia Flexuosa And Cordylophora Lacustris, Patricia Marie Brown Jan 1981

Microelectrophoretic Separation Of Isozymes In Relation To Aging In The Hydroids Campanularia Flexuosa And Cordylophora Lacustris, Patricia Marie Brown

Master's Theses

No abstract provided.


Selection Of Somatic Cell Hybrids Between Baby Hamster Kidney Cells And Human Embryonic Kidney Cells To Study Bk Virus Early Gene Expression, Sara Lynn Ehlke Jan 1981

Selection Of Somatic Cell Hybrids Between Baby Hamster Kidney Cells And Human Embryonic Kidney Cells To Study Bk Virus Early Gene Expression, Sara Lynn Ehlke

Master's Theses

No abstract provided.


Phytogeography Of South Padre Island, Texas, Robert I. Lonard, Frank W. Judd Nov 1980

Phytogeography Of South Padre Island, Texas, Robert I. Lonard, Frank W. Judd

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

The phytogeographic affinities of the native flora of South Padre Island, Texas, are analyzed and the probable dispersal agent(s) for each species identified. The native flora consists of 99 species and 44% of the species also occur on the adjacent Texas mainland; 28% of the native species have tropical affinities. Only three species have probably dispersed from the island to the mainland. Two species may be endemic to Padre Island and the Tamaulipan barrier islands. Most of the tropical species have reached the island by oceanic drift, but birds are the most important dispersal agent for the native species. Man …