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Articles 1621 - 1650 of 2824
Full-Text Articles in Entire DC Network
The Effects Of Gonadotropin Releasing Hormone And Milk Production On Pregnancy Rates In Repeat Breeder Dairy Cows, Laura Maureen Mitchell
The Effects Of Gonadotropin Releasing Hormone And Milk Production On Pregnancy Rates In Repeat Breeder Dairy Cows, Laura Maureen Mitchell
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
One hundred sixteen third- and fourth-service lactating dairy cows from five cooperating herds were used to compare the pregnancy rate of cows given Gonadotropin Releasing Hormone five minutes following insemination with pregnancy rate of control cows. In addition, milk production level, age at service and days in milk at time of service were used to compare pregnancy rates. Milk production level was expressed as relative value (percent of herd mature equivalent production). There were no differences between treated and untreated control cows in pregnancy rate. In addition, there were no differences between service number (3 or 4), relative value group, …
The Highest Local Density Of Reinforcement Controls Overall Post-Reinforcement Pause Duration On Ratio Schedules, Elliott J. Bonem
The Highest Local Density Of Reinforcement Controls Overall Post-Reinforcement Pause Duration On Ratio Schedules, Elliott J. Bonem
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A series of experiments were conducted with pigeons to investigate the variables responsible for differential postreinforcement pause (PRP) durations found on ratio schedules. In Experiment I, behavior on fixed-ratio (FR) and variable-ratio (VR) schedules were compared to behavior evoked by two interpolated schedules. The addition of a single FR 1 component to the FR 50 baseline schedule reduced the overall PRP to a duration comparable to that found on the VR 50 schedule. The addition of both an FR 1 and an FR 215 component to an FR 50 baseline reduced PRP and IRT durations below those on a VR …
The Effects Of Reinforcement Magnitude And Temporal Contingencies On Pre-Ratio Pause Duration, Marilyn K. Bonem
The Effects Of Reinforcement Magnitude And Temporal Contingencies On Pre-Ratio Pause Duration, Marilyn K. Bonem
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The present study was conducted to determine whether conjugate magnitude and temporal contingencies were effective in increasing the pre-ratio pause (PRP) duration and to determine the controlling variables that govern such contingencies. It has been reported in the literature that magnitude of reinforcement, if presented contingently, is effective in controlling performance and that inserting intervals of blackout (BO), during which responding does not lead to reinforcement, virtually always leads to control of responding, even though it has not been presented contingently. The conjugate schedules experimentally arranged reinforcement such that the longer the PRP, the longer was the duration of access …
Classical Conditioning And Immune Reactivity In Rats, Laura Anne Czajkowski
Classical Conditioning And Immune Reactivity In Rats, Laura Anne Czajkowski
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Psychoneuroimmunology is an interdisciplinary area that examines the interaction between behavior, the central nervous system, and the immune system. Many investigations have utilized a taste aversion paradigm to examine the effects of classical conditioning on an immune response. The procedure generally consists of an animal ingesting a novel flavor, and then being made ill and immunosuppressed by injection of a pharmacological agent. The animal is provided access to that flavor at a later time. The rejection of the novel flavor on the test day is called taste aversion and the depressed antibody titer has been labeled conditioned immunosuppression.
The present …
The Correlation Between Life Satisfaction And Farm Involvement Among Utah Dairy Farm Men And Women, Phillip S. Browning
The Correlation Between Life Satisfaction And Farm Involvement Among Utah Dairy Farm Men And Women, Phillip S. Browning
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of this study is to look at the relationship between life satisfaction and farm involvement among dairy farm men and women in Utah. Farm involvement is defined as farm tasks, decision making, and participation in farm organizations. A sample of 116 couples were drawn from five counties in Utah. The husbands and wives were each interviewed separately. The sample is representative of the dairy farms in these five counties. However, the results of this study cannot be generalized to other types of farms in Utah or dairy farms from other locations.
The correlation between life satisfaction and farm …
The Immunological And Neurochemical Toxicity Of Benzene And Its Interaction With Toluene In Mice, Gin-Chang Hsieh
The Immunological And Neurochemical Toxicity Of Benzene And Its Interaction With Toluene In Mice, Gin-Chang Hsieh
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Benzene and toluene are known groundwater contaminants . Male CD-I mice were continuously exposed to 0, 31, 166, and 790 mg/ L benzene and 0, 17, 80, and 405 mg/L toluene, respectively, in drinking water for four weeks. Benzene caused a reduction of leukocytes, lymphocytes and erythrocytes, and resulted in a macrocytic anemia. Lymphocyte response to both B- and T-cell mitogens, mixed lymphocyte response to alloantigens, and the ability of cytotoxic lymphocytes to lyse tumor cells were enhanced at the lowest dose of benzene and depressed in the higher dosage animals. Benzene at doses of 166 and 790 mg/L decreased …
Structure-Activity Relationships Of Retinoids In Developmental Toxicology, W. Brian Howard
Structure-Activity Relationships Of Retinoids In Developmental Toxicology, W. Brian Howard
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The teratogenic potency of retinoid analogs was determined in Syrian hamsters and compared to the teratogenic potency of all-trans-retinoic acid (all-trans-RA, ED50 = 10.5 mg/kg). A total of 15 analogs having variations in the cyclohexene ring were evaluated following various amounts of single oral doses on day 8 of gestation. Retinoids containing a five- or six-membered ring were as teratogenic as all-trans-RA, provided they had sufficient lipophilic substituents on the ring. The same pattern emerged for retinoids that had six-membered aromatic ring substitution for the natural cyclohexene ring of vitamin A. Incorporation of a supplementary …
Studies On Encephalomyocarditis Virus-Induced Diabetes In Mice, John Henry Huffman
Studies On Encephalomyocarditis Virus-Induced Diabetes In Mice, John Henry Huffman
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The D-variant of encephalomyocarditis (EMC-D) virus was given to SJL/J mice by the artificial, intraperitoneal (ip) route of infection, or by the natural routes of infection per os (po) or intranasal (i.n.), in comparable concentrations. The po route of infection was found to be ineffective. Mice given virus by either the ip or i.n. routes of infection became diabetic. Mice were more resistant to the infectious and diabetogenic properties of the virus when given by the i.n. than when given by the ip route. Glycosuria in mice given virus i.n. usually lagged one day behind that in mice given virus …
Interactions Of Vanadium Compounds With Reducing Equivalents: Evidence Of Free Radical Involvement And Possible Mechanisms Of Toxicity, Randal J. Keller
Interactions Of Vanadium Compounds With Reducing Equivalents: Evidence Of Free Radical Involvement And Possible Mechanisms Of Toxicity, Randal J. Keller
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Vanadium compounds have been reported to cause numerous toxicological effects including NAD(P)H oxidation and lipid peroxidation. The purpose of this thesis is to determine the active form of vanadium in causing these effects, and to determine any possible free radical involvement in these processes. Vanadium-stimulated oxidation of NADH was studied spectrophotometrically and by electron spin resonance spectroscopy. In 25 mM sodium phosphate buffer at pH 7. 4, vanadyl, (V(IV)), is slightly more effective in stimulating NADH oxidation than was vanadate (V(V)). Addition of a superoxide generating system, xanthine/xanthine oxidase, results in a marked increase in NADH oxidation by vanadyl, and …
Luteinizing Hormone An Progesterone Response To Gnrh Administration At Insemination In Repeat-Breeder Holstein Cows, Robert Joseph Callan
Luteinizing Hormone An Progesterone Response To Gnrh Administration At Insemination In Repeat-Breeder Holstein Cows, Robert Joseph Callan
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Several studies suggest that the administration of GnRH near the time of insemination improves pregnancy rates in cattle. It has also been reported that there is greater improvement in repeat-breeder animals than at first service. The mechanism for this observation has not been established. Twenty-eight lactating Holstein cows that returned to estrus after one or more inseminations from the USU Caine Dairy were used in the study. Animals were randomly divided into two treatment groups, intramuscular administration of 100 ug GnRH or saline control at the time of insemination. Blood samples were collected at 1, 1.5, 2, 2.5, 3 and …
Effect Of Feeding A Viable Yeast Culture On Ruminal Fermentation Characteristics, Milk Production Response And Apparent Nutrient Digestibility In Holstein Cattle, Mohamed H. Shokair
Effect Of Feeding A Viable Yeast Culture On Ruminal Fermentation Characteristics, Milk Production Response And Apparent Nutrient Digestibility In Holstein Cattle, Mohamed H. Shokair
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Four barren Holstein cows fitted with ruminal fistulas were assigned to each of two dietary treatments in a replicated 2 x 2 Latin square design. Treatments consisted of a basal ration and a basal ration plus 10g/d of a viable yeast culture (Saccharomyces cerevisiae). Cows were fed treatments for a 21-day adaption followed by a 7-day collection period. Total ruminal bacteria, cellulolytic bacteria and protozoa were unaffected by treatment. Feeding the viable yeast culture significantly increased ruminal acetic acid and acetic/propionic ratio. Molar percentage of propionic, isobutyric, isovaleric and valeric acids and rumen ammonia-N levels were significantly reduced …
Big Game Depredation To Crops And Orchards In Seven Counties Of Northern And Central Utah: A Case Study, Kerry C. Mcbride
Big Game Depredation To Crops And Orchards In Seven Counties Of Northern And Central Utah: A Case Study, Kerry C. Mcbride
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Depredation to crops and orchards is a problem for agricultural producers in many states where big game are in close proximity to land used for ag-production. Heavy snowfall has created a serious big game depredation in Utah in recent years. Heavy snowfall covers big game feed during winter months, which creates a serious demand on cultivated land to maintain the big game herds at current levels. Many operators believe that current big game herd sizes are too large available feed, and should be reduced to prevent damage to agricultural production. Many big game managers believe otherwise.
This study looked at …
Control And Evaluation Of Big Game Browsing Damage To Commercial Fruit Orchards, William E. Stone
Control And Evaluation Of Big Game Browsing Damage To Commercial Fruit Orchards, William E. Stone
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Diversionary feeding, artificial feeding designed to divert animals away from areas where they might cause property damage, was tested for efficacy in reducing fruit orchard browsing by big game animals during two consecutive winters in Utah. Strategically placed attractive feedstuffs lured deer to feed stations and reduced fruit-bud browsing (1st year, P < 0.07; 2nd year, P < 0.01). Blossom and apple numbers were greater (P < 0.05) on trees in the feed (treatment) orchard than in the no feed (control) orchard in each year. However, higher (P < 0.05) apple production on trees where browsing was excluded in the treatment orchards compared to the control orchards indicated that intercept feeding did not increase crop production. Tree periodicity and other factors affecting apple production masked the effect of diversionary feeding on crop yield.
Two independent browsing damage assessment methods, a paired-tree technique and a harvest-inflation technique, predicted that the ratio of apples lost per browsed bud was 0.158 and 0.082, respectively. However, the values of the ratio varied widely with each method of estimation. Browsing damage differed ( …
The Effects Of Forest Harvesting On Small Mammals In Western Newfoundland And Its Significance To Marten, Brian Tucker
The Effects Of Forest Harvesting On Small Mammals In Western Newfoundland And Its Significance To Marten, Brian Tucker
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The depauperate fauna of Newfoundland provides a limited prey base for marten. Only two small mammal prey species, Microtus pennsylvanicus and Sorex cinereus, were found in any abundance in the old-growth forests of the study area. Of these two, Microtus displayed population fluctuations typical of most microtines. Analysis of marten scats indicated that Microtus is a very important prey item to the marten with other food. items being of lesser importance particularly when Microtus are abundant.
Trapping in various habitats indicated that Sorex densities were three to five times higher in logged areas compared to uncut areas. Unfortunately, the …
The Feasibility Of River Otter Reintroduction In Northern Utah, Joel P. Bich
The Feasibility Of River Otter Reintroduction In Northern Utah, Joel P. Bich
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of this thesis is to document river otter (Lutra canadensis) distribution and reintroduction potential in northern Utah. Distribution was studied using data from 3 sources: 1) otter sighting records from Utah Division of Wildlife Resources; 2) surveys of Utah furbearer trappers and natural resources personnel; and 3) searches of streams for otter sign. Potential for river otter habitat/reintroduction was evaluated by assessing food, cover, and reintroduction attributes. Streams were ranked using an evaluation system based on data from the otter literature.
Forty-six positive otter sightings were made in Utah by trappers, natural resources personnel, and the …
The Role Of Homeostatic Imbalance In The Reported Immunomodulation Of T-2 Toxin, Michael Jay Taylor
The Role Of Homeostatic Imbalance In The Reported Immunomodulation Of T-2 Toxin, Michael Jay Taylor
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
T-2 toxin (T-2), produced by the genus Fusarium, is a cytotoxic trichothecene mycotoxin, a feed contaminant, and has been shown to be immunomodulatory. It is suspected that T-2-associated immunomodulation is mediated partly through the hypothalamic-pituitary-adrenal axis. The presence of endotoxin, a bacterial product capable of activating the hypothalamic-pituitary-adrenal axis as well as the levels of several hormones, also associated with activation of the hypothalamic-pituitary-adrenal axis, were determined in both vehicle- and toxin-treated animals. Endotoxemia was evident twenty-four hours after a single oral exposure to T-2. Blood levels of adrenocorticotropic hormone and corticosterone, parameters of the stress response, also increased …
Maternal Iron Parameters And Diet: Influence On Infant Iron Parameters And Development, Janet Bradshaw Anderson
Maternal Iron Parameters And Diet: Influence On Infant Iron Parameters And Development, Janet Bradshaw Anderson
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of this study was to determine and evaluate the dietary intake of pregnant women living in this geographical area, evaluate how their diets related to their iron status, how their nutrient intakes compared with other studies, and how their iron status and diet affected infant iron status and development, as assessed by the Bayley Scale of Infant Development.
The study involved 32 pregnant women who were between 8 to 14 weeks gestation and 20 to 35 years of age. They were followed through pregnancy and their infants were followed until three months of age.
Three-day dietary records, a …
The Bioavailability Of Iron From Meat, Spinach, Soy Protein Isolate, Meat:Spinach And Meat:Spi Mixtures Fed To Anemic And Healthy Rats, Dejia Zhang
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Two Experiments were conducted to investigate the effect of iron status and iron source on iron bioavailability using the rat model. Beef was proportionally mixed with spinach (Experiment I) or soy protein isolate (Experiment II) to test if meat enhances the absorption of iron from spinach or SPI. Five diets with the iron from meat:spinach (or SPI) ratios of 100:0, 75:25, 50:50, 25:75 and 0:100 were prepared and fed to rats. FeS04 was used as a reference. Two trials of rats were used in Experiment I. In trial I, half of the rats were made severely iron deficient (Hb 6.3 …
The Effect Of Elaboration On Memory: Self-Generated Elaboration Vs Experimenter-Provided Elaboration, Sung-Il Kim
The Effect Of Elaboration On Memory: Self-Generated Elaboration Vs Experimenter-Provided Elaboration, Sung-Il Kim
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of this study was to investigate the effect of elaborations on memory. Two types of elaborations (self-generated elaboration and experimenter-provided elaboration) were examined. The experiment consisted of three phases (incidental learning phase, immediate test phase, and delayed test phase). In the incidental learning phase, subjects were asked to make plausibility judgments about 28 fictitious episodes. Half of these were about well-known individuals and the other half were about unknown individuals. Each name (either well-known or unknown) was presented with either two supportive facts or without the supportive facts. During the immediate test phase, subjects were given unexpected memory …
Durational Control Of Defensive Burying In Rats: An Investigation Of A Species-Specific Defense Reaction, Stephen Gregory Goldberg
Durational Control Of Defensive Burying In Rats: An Investigation Of A Species-Specific Defense Reaction, Stephen Gregory Goldberg
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Six experiments were run to determine whether the duration of conditioned defensive burying (COB) in rats is a function of its consequences.
Four experiments developed the methodology. Experiment 1 replicated the standard one-trial experiment, where rats are shocked once by a prod. All three rats exhibited CDB. Experiment 2 used a lever-press-for-water contingency to force recontact with the lever, following shock deliveries in Sessions 6 and 14. All three rats buried the lever in both sessions. Experiment 3 replicated Experiment 2, employing albino and hooded rats. All six buried the lever. The albinos exhibited longer burying durations. Experiment 4 used …
The Effects Of Prey Vulnerability, Density, And Patch Replenishment In An Operant Analogue Of Foraging, Michael James Dewulf
The Effects Of Prey Vulnerability, Density, And Patch Replenishment In An Operant Analogue Of Foraging, Michael James Dewulf
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Foraging behavior has recently become a popular area of research with which ethologists, behavioral ecologists, and experimental psychologists converge their traditionally separate disciplines into a more multidisciplinary framework. Ethologists and behavioral ecologists usually study foraging as it occurs in the natural environment or the "field," while experimental psychologists contrive laboratory simulations of foraging and make the assumption, sometimes incorrectly, that generalization occurs across settings, situations, and species. Scientific advances are now beginning to occur in the ability of laboratory researchers to better simulate foraging as it occurs in the field. Field researchers are also becoming more willing to accept these …
Problems Of Data Collection For Economic Research In Small Farmer Agriculture: Some Experience In Somalia, Aden Abdullahi Aw-Hassan
Problems Of Data Collection For Economic Research In Small Farmer Agriculture: Some Experience In Somalia, Aden Abdullahi Aw-Hassan
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purposes of this thesis are twofold. The first is to show problems encountered in collecting and analyzing data on small-holder agriculture. The second is to describe the role of data in supporting research and rationalization of alternatives for sustaining agricultural strategies in development.
Data collected from six villages of the Lower Shebelle Region of Somalia are taken as a case study to show the difficulties encountered in procurement and analysis of that data. The thesis discusses data collection methods that ensure gathering adequate data that can be used to undertake production economics and farm management research. The thesis also …
Effect Of Bacterial Inoculant On Alfalfa Haylage: Ensiling Characteristics And Milk Production Response When Fed To Dairy Cows In Early Lactation, Barb Kent
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Third-cutting alfalfa hay harvested at bud stage in each of 2 yrs, treated with a live bacterial inoculant, packed in polyethylene-bonded bags and allowed to ensile. In both years, treated haylage had a lower pH, and a period effect was found for pH and mold count, regardless of treatment. In year 1, there was a period effect found for acid detergent fiber. In year 2, mean lactic-acid-producing bacteria numbers (log 10) were significantly higher for treated haylage (9.69 and 10.36) for control and treated haylage, respectively). Regardless of treatment, lactic-acid-producing bacteria numbers and water soluble carbohydrates significantly declined through time. …
Nitrogen And Energy Budgets Of Production Ewes On Summer Range In Southwestern Utah, John W. Halpop
Nitrogen And Energy Budgets Of Production Ewes On Summer Range In Southwestern Utah, John W. Halpop
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Nitrogen (N) and energy budgets for free-roaming ewes were quantified on mountain summer range in southwestern Utah in 1986 and 1987. Diet quality (%N), in vitro organic matter digestibility (IVOMD), and energy were estimated with the use of five esophageally fistulated ewes. Excretion rates of N and energy to feces and urine were measured by total collection from five nonfistualted ewes.
Total intake N(gN/(MBW*d-1) tracked intraseasonal changes of dietary N percent but was apparently buffered by fluctuations in dry matter intake. In each year, total urine N was closely related to dietary N concentration, r2=0.97 (1986) …
Comparison Of Post-Weaning Performance And Carcass Traits Of Columbia And Cormo Crossbred Lambs, Carl Kim Chapman
Comparison Of Post-Weaning Performance And Carcass Traits Of Columbia And Cormo Crossbred Lambs, Carl Kim Chapman
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Thirty-seven Columbia and Cormo Crossbred July-weaned weather lambs were utilized in this study. A feeding trial was conducted to evaluate feed efficiency, average daily gain, feed cost per pound of gain, wool growth per day and per pound of grain, and average wool fiber diameter and distribution of fiber population of the wool. Lambs were raised to a uniform market weight of between 115 and 125 pounds and slaughtered to evaluate carcass weight, backfat thickness, loin eye area, internal body fat, leg circumference, dressing percentage, untrimmed wholesale cuts, trimmed retail cuts, and yield and quality grades. Suffok x Cormo/Rambouillet lambs …
Woman's Exponent: Cradle Of Literary Culture Among Early Mormon Women, Alfene Page
Woman's Exponent: Cradle Of Literary Culture Among Early Mormon Women, Alfene Page
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of this paper was to define and discuss the early Mormon women's newspaper, Woman's Exponent, and its editors in developing a literary culture among Mormon women. Woman's Exponent served as the primary source of research to show through its literature that the women of Utah were encouraged to express themselves freely, and present their way of life to a world that held a grossly distorted view of them. The Exponent provided the forum for skilled writers to polish their craft, and new writers to develop their talents. The literary influence of the Exponent encouraged the women writers …
Gambel Oak For Spanish Goats: A Digestion-Balance Evaluation Of Nutrient Availability, Brian L. Dick
Gambel Oak For Spanish Goats: A Digestion-Balance Evaluation Of Nutrient Availability, Brian L. Dick
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Fresh-harvested Gambel oak (Quercus gambelii) browse was mixed with chopped alfalfa hay to formulate six diets, varying in oak content at two phenological stages. Diets included juvenile oak (65,80,95%), mature oak (40,80%), and an alfalfa control. Diets were evaluated for goats using a series of total-collection digestion balance trials. Dry matter intake was highest for animals on mature oak diets, and lowest on diets containing a high percentage of juvenile oak, possibly due to differences in diet dry matter content. Apparent digestibility of dry matter and cell wall components was lowest for mature oak diets, and highest for …
Acquisition Of Forgaging Skills By Lambs Eating Grass Or Shrub, Enrique R. Flores
Acquisition Of Forgaging Skills By Lambs Eating Grass Or Shrub, Enrique R. Flores
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
I studied the acquisition of foraging skills by lambs eating shrub or grass in three experiments. The general approach was to isolate those skills involved in prehending forage from those related to the acceptance of novel foods. Treatment lambs received 15 times more exposure to grass or shrub than did control lambs. Lambs were tested in 2.5 x 2.5 meter monocultures of shrub or grass 5 min/d, on two separate occasions. Height, bulk density and spatial arrangement of plant material were controlled during testing.
In Experiment 1, I studied the acquisition of foraging skills by lambs on monocultures of shrubs. …
A Model Of Energy Expenditure In White-Tailed Jackrabbits (Lepus Townsendii) Based On Integrated Studies Of Energetics And Field Ecology, Gordon L. Rogowitz
A Model Of Energy Expenditure In White-Tailed Jackrabbits (Lepus Townsendii) Based On Integrated Studies Of Energetics And Field Ecology, Gordon L. Rogowitz
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Field and laboratory studies were conducted to develop a model of energy expenditure in a population of white-tailed jackrabbits (Lepus townsendii). Field work in southwestern Wyoming during 1985-87 showed that the breeding season commenced at snowmelt and ceased during late- July drought. Adult females reproduced relatively synchronously and produced a mean of three litters annually. Greatest fetal production occurred in the second litter period. Collections indicated a 1:1 sex ratio, few jackrabbits >2 years-old, and a density of 7 animals / km2 in the population. Postnatal growth was sigmoidal, culminating in heavier adult females than males. Using …
Nesting And Habitat Parameters For Selected Raptors In The Desert Of Northwestern Utah, David L. Peterson
Nesting And Habitat Parameters For Selected Raptors In The Desert Of Northwestern Utah, David L. Peterson
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
This study examined the effects of habitat parameters, disturbances and predation on the reproductive success of golden eagles (Aguila chrysaetos), ferruginous hawks (Buteo regalis), red-tailed hawks (Buteo jamaicensis) and prairie falcons (Falco mexicanus) in the desert area southwest of the Great Salt Lake in northwestern Utah.
The prairie falcon was the only species examined that had a normal reproductive output during the study years of 1984-1986. The prairie falcon was better able to utilize the avian prey species which were very difficult for the larger and slower raptor species to capture. During …