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Economic Changes From The Use Of Biotechnology In Production Agriculture, Loren W. Tauer Jan 1988

Economic Changes From The Use Of Biotechnology In Production Agriculture, Loren W. Tauer

Journal of the Iowa Academy of Science: JIAS

The potential economic impact of biotechnology in production agriculture is discussed. There are challenges and difficulties in completing economic research when little production information is available on biotechnologies. I argue that little impact differences exist between cost-reducing versus output-increasing technological change. Rapid technological change results in low average returns in agriculture but continuous early innovators earn higher returns. Various plant and animal technologies are presented and discussed.


Electrophoretic, Morphometric, And Meristic Comparisons Of Walleye Broodstock In South Dakota, Chantel M. Waltner Jan 1988

Electrophoretic, Morphometric, And Meristic Comparisons Of Walleye Broodstock In South Dakota, Chantel M. Waltner

Electronic Theses and Dissertations

Electrophoretic and morphological variability among walleyes collected from three upper Missouri River tributaries and a glacial lake in South Dakota was investigated, and an upper Mississippi River stock was electrophoretically compared to the South Dakota stocks. Allele frequencies of two (MDH-3, GMP-3) of the twenty-one loci examined differed significantly (P<0. 05) between South Dakota and Mississippi River walleyes. Contingency chi-square tests of allele frequencies showed homogeneity among walleyes from the Missouri River tributaries, and significant (P<0.001) heterogeneity (P<0.001) at the GMP-3 locus between Missouri River and glacial lake stocks. A dendogram derived from Nei unbiased genetic identity values produced separate branchings for the South Dakota and Mississippi River walleyes. All four walleye stocks in South Dakota were morphologically variable, although no one character could be used as a diagnostic tool to separate the stocks visually. Discriminant function analysis of eight of the most powerful discriminatory characters was successful in correctly classifying walleyes by origin with 83-97% accuracy.


Forage Potential Of Seasonal Wetlands, Daniel Edward Hubbard Jan 1988

Forage Potential Of Seasonal Wetlands, Daniel Edward Hubbard

Electronic Theses and Dissertations

Investigations on aspects of seasonal wetland forage potential were conducted in eastern South Dakota. The quantity and quality of the standing crop of vegetation in 6 seasonal wetland communities were assessed at the end of the growing season in 1983 and in 2 seasonal-wetland-dominated basins and their associated uplands (native mixed-grass prairie) over the growing season in 1985. Crude protein (CP), ash, detergent fiber, and in vitro digestible dry matter (IVDDM) values were measured on the above-ground material of whitetop [Scolochloas festucacea (Willd.) Link], slough sedge (Carex atherodes Spreng.), burred (Spargnaium eurycarpum Engelm.), and smartweed (Polygonum amphibium L. var. emersum …


Production Of Triploid Rainbow Trout For Evaluation In South Dakota Waters, Jeff C. Dillon Jan 1988

Production Of Triploid Rainbow Trout For Evaluation In South Dakota Waters, Jeff C. Dillon

Electronic Theses and Dissertations

In September 1986, approximately 50,000 rainbow trout (Salmo gairdneri) eggs were fertilized and subjected to heat shocks to prevent expulsion of the second polar body, theoretically resulting in triploid embryos. Heat shocks were at 26 and 28°c, began 10, 20, 30, or 40 min after fertilization, and lasted for 10 or 20 min for a total of 16 treatments. Another 25,000 eggs served as controls and were handled identically but at a normal water temperature of 12°c. Cumulative hatching rates for eggs that were heat-shocked at 26 and 28° were 64 and 50%, respectively, compared to control eggs which had …


Winter 1988, Nsu Oceanographic Center Jan 1988

Winter 1988, Nsu Oceanographic Center

Currents

No abstract provided.


Summer 1988, Nsu Oceanographic Center Jan 1988

Summer 1988, Nsu Oceanographic Center

Currents

No abstract provided.


Spring 1988, Nsu Oceanographic Center Jan 1988

Spring 1988, Nsu Oceanographic Center

Currents

No abstract provided.


Evolutionary Genetics And Morphometrics Of A Cave Crayfish Population From Chiapas (Mexico), Valerio Sbordoni, Giuliana Allegrucci, Fabiola Baldari, Donatella Cesaroni Jan 1988

Evolutionary Genetics And Morphometrics Of A Cave Crayfish Population From Chiapas (Mexico), Valerio Sbordoni, Giuliana Allegrucci, Fabiola Baldari, Donatella Cesaroni

International Journal of Speleology

The recently explored Cueva de Los Camarones, in the remote village of Constitucion, Chiapas, Mexico, houses a unique highly variable population of Procambarus crayfish (Crustacea, Decapoda). Morphologically, a more or less clinal variation is revealed at several features such as the degree of rudimentation in both pigmentation and eye, and the elongation of body and appendages. Extremes are quite different, ranging from typical dark, thick, eyed individuals to light, elongated, microphtalmic phenotypes. Evolutionary relationships among individuals were investigated electrophoretically (25 structural gene loci) and morphometrically (12 characters) by means of multivariate analyses. Results from analysis of individual allozymic multilocus profiles …


Production Effects Of Biotechnology In The Dairy Industry: An Exploratory Study, Kenneth L. Schurter Jan 1988

Production Effects Of Biotechnology In The Dairy Industry: An Exploratory Study, Kenneth L. Schurter

Theses

Genetically engineered products are being produced at an economical level. products is bovine sornatotropin. One of these Injections of bovine sornatotropin increase milk yield in dairy cattle. This increase in production per cow is consistent with the thirty year trend of fewer dairy farms, fewer cows, and more milk per cow.

Starting in the 1950's in the mechanical era, farmers went from horses to tractors. In the chemical era, herbicides and fertilizers started being used. Now in the 1980's the technical era is coming in to existence . Through all of these era's there was controversy. Each of these era's …


Looking At Lupins - Lupin Management In The South Eastern Wheatbelt, W. L. Smart, M. M. Ralph, J. M. Liddle, R.. D. Ramm, C. J. Robinson, E. W. Armstrong Jan 1988

Looking At Lupins - Lupin Management In The South Eastern Wheatbelt, W. L. Smart, M. M. Ralph, J. M. Liddle, R.. D. Ramm, C. J. Robinson, E. W. Armstrong

Grain and other field crops research reports

In the past couple of years research into lupins has increased substantially particularly in the fields of weed control, seeding rates, and control of diseases such as brown leaf spot and pleiochaeta root rot. This report is a summary of the lupin trials in the Lake Grace advisory area as well as a guide to better lupin farming.


Consequences Of Thymidine Catabolism For Estimates Of Bacterial Production: An Example From A Coastal Marine Sediment, Kevin R. Carman, Fred C. Dobbs, James B. Guckert Jan 1988

Consequences Of Thymidine Catabolism For Estimates Of Bacterial Production: An Example From A Coastal Marine Sediment, Kevin R. Carman, Fred C. Dobbs, James B. Guckert

OES Faculty Publications

Radioactively labeled thymidine (TdR) has been used extensively to measure bacterial production in aquatic environments, but critical assumptions of the TdR technique often have gone untested. In this study of a coastal marine sediment, the metabolic fate of methyl [3H]TdR and methyl [14C]TdR was at variance with the assumptions necessary for determining bacterial production. Only 2% of incorporated radioactivity was recovered in the DNA fraction of TCA-insoluble material following time-course incubations of l-300 min. At least the methyl group of TdR was extensively catabolized, as shown by copious production of 14C02. The temporal …


Time Delayed Protein Complementation, Diana L. Lakusta Dec 1987

Time Delayed Protein Complementation, Diana L. Lakusta

Loma Linda University Electronic Theses, Dissertations & Projects

The time delayed complementation of plant proteins was tested in weanling Sprague-Dawley male rats by measuring growth rates as well as plasma and tissue free amino acids. Diets of pinto beans with rice, corn or wheat were pair-fed in combination or alternating 4 times a day at 6 and 11 am, and 4 and 9 pm for 4 weeks. Plasma, liver and muscle samples were obtained 2 hours postprandial, a time determined most suitable for sacrifice, and analyzed for free amino acids via ion-exchange chromatography. There were no significant differences in growth of rats fed combination or alternating diets.during week …


Lake Mead Prefertilization Study: Preliminary Nutrient Enhancement Studies In Lake Mead, Richard P. Axler, Larry J. Paulson, Patrick J. Sollberger, Donald H. Baepler, U.S. Bureau Of Reclamation Nov 1987

Lake Mead Prefertilization Study: Preliminary Nutrient Enhancement Studies In Lake Mead, Richard P. Axler, Larry J. Paulson, Patrick J. Sollberger, Donald H. Baepler, U.S. Bureau Of Reclamation

Publications (WR)

Studies conducted by the University of Nevada-Las Vegas (UNLV), the Nevada Department of Wildlife (NDOW), the Arizona Game and Fish Department (AGFD), The Nevada Division of Environmental Protection (NDEP), and the United States Bureau of Reclamation (USBR) have identified decreased algal production as a major factor involved in the decline of the Lake Mead sport fishery. Phosphorus-laden silt particles in the Colorado River have been sedimenting out in Lake Powell since the completion of Glen Canyon Dam 286 miles upstream in 1963. This sharp decrease in phosphorus loading to Lake Mead (>5000 tons per year) has resulted in decreased …


The Bird Strike Hazard (Bash) Program, Capt. Edgardo R. Farrraro, Capt. Russell P. Defusco Oct 1987

The Bird Strike Hazard (Bash) Program, Capt. Edgardo R. Farrraro, Capt. Russell P. Defusco

Eastern Wildlife Damage Control Conference: 3rd (1987)

The hazards birds pose to aircraft has been of concern to the Air Force for more than 20 years. After losing several aircraft due to bird strikes in the early 1960's, the Air Force formed a team to evaluate bird hazards to Air Force aircraft. The team, from the Air Force Weapons Laboratory (AFWL) at Kirtland AFB NM, handed over this mission to the Bird Aircraft Strike Hazard (BASH) Team at HQ Air Force Engineering and Services Center (AFESC) at Tyndall AFB in 1975. In 1986 (October) the BASH team moved to Boiling AFB, Washington DC.

The Air Force sustains …


Preliminary Testing Of A Selenium-Based Systemic Deer Browse Repellent, T.R. Angradi, W.M. Tzilkowski Oct 1987

Preliminary Testing Of A Selenium-Based Systemic Deer Browse Repellent, T.R. Angradi, W.M. Tzilkowski

Eastern Wildlife Damage Control Conference: 3rd (1987)

Silviculturists use a variety of techniques, including repellents, to reduce browse damage by white-tailed deer (Odocoileus virginianus) to valuable eastern hardwood seedlings. Systemic selenium, sodium selenite, was evaluated with captive white-tailed deer for its repellency in white ash (Fraxinus americana) and black cherry (Prunus serotina) seedlings. Selenium had no effect in reducing browsing of black cherry. However, there was a reduction (p<0.05) in the white ash browsing level.


A Review Of Machinery For Cropping With Reduced Water Erosion, K J. Bligh Oct 1987

A Review Of Machinery For Cropping With Reduced Water Erosion, K J. Bligh

Resource management technical reports

No abstract provided.


Molting In The Mature Female Blue Crab, Callinectes Sapidus, Rathbun, Kirk J. Havens Oct 1987

Molting In The Mature Female Blue Crab, Callinectes Sapidus, Rathbun, Kirk J. Havens

OES Theses and Dissertations

The present study examines the hypothesis that mature female blue crabs, Callinectes sapidus, do not have a terminal anecdysis. Induced molting via eyestalk ablation, size frequency distributions and gonad and limb regeneration indices from field collected animals are used as indicators of potential post maturity molts.

Eyestalk ablation of mature females resulted in ecdysis approximately 51 days after ablation, indicating a physiological ability if mature females to complete ecdysis. Analysis of size frequency distributions indicates two distinct shifts from smaller to larger females, one in early spring and a second in early fall. While migration of larger females into …


Soil Microbes And Biotechnology, M. Scott Smith Aug 1987

Soil Microbes And Biotechnology, M. Scott Smith

Soil Science News and Views

There is nothing new about attempts to develop and market microbial products for crop or soil improvement. Several types of microbes have been sold for a variety of agronomic purposes for many years. With the important exception of rhizobial inoculants. these have been generally unsuccessful. Recently however. the scientific revolution in genetics and molecular biology, the need for low cost agronomic inputs. and widespread concern for environmental safety have tremendously stimulated research and commercial activity on microbial products. Claims that cheap, effective microbial inoculants can be developed for pest control, detoxifying pollutants, providing plant nutrients and improving soils have been …


Estimation Of Food Limitation In Daphnia Pulex From Boulder Basin, Lake Mead, Thomas Mark Bartanen Aug 1987

Estimation Of Food Limitation In Daphnia Pulex From Boulder Basin, Lake Mead, Thomas Mark Bartanen

Publications (WR)

In February, 1982 I began a year-long study to determine if growth and reproduction in Daphnia Pulex were limited by the amount of food available in Boulder Basin, Lake Mead. To determine this, I made monthly collections of Daphnia Pulex and natural lake seston from an already established station in Boulder Basin. I cultured the Daphnia Pulex under simulated field conditions in a flow-through feeding apparatus using four different food regimes; 1-natural lake seston filtered through 80 um mesh to remove other zooplankton, 2-lake seston (as above) with an enrichment of 103 cells-ml-1 of Chlamydomonas reinhardti, 3-lake …


Analysis Of The Water-Quality Standards Proposed By The Nevada Division Of Environmental Protection, City Of Las Vegas, Nevada Aug 1987

Analysis Of The Water-Quality Standards Proposed By The Nevada Division Of Environmental Protection, City Of Las Vegas, Nevada

Publications (WR)

The Nevada Division of Environmental Protection (DEP) has proposed water-quality standards, applicable to Las Vegas Bay and Lake Mead, for (1) chlorophyll, (2) un-ionized ammonia, and (3) pH.

We have concluded that the proposed standards are unlikely to protect or improve water quality in Lake Mead. The proposed chlorophyll standard:

May harm the fishery. Lakes with more chlorophyll have greater fish production.

Will not improve clarity. Chlorophyll concentrations above 30 ug/1 have little effect on clarity.

Will not protect against scums or dominance by blue-green algae. Lake Mead shows no consistent relationship between chlorophyll and scums or blue-green dominance.

Will …


Analysis Of Phytoplankton And Particle Variability At A Warm Core Ring/Shelf Break Front Using Flow Cytometry, Kimberly G. Davis Jul 1987

Analysis Of Phytoplankton And Particle Variability At A Warm Core Ring/Shelf Break Front Using Flow Cytometry, Kimberly G. Davis

OES Theses and Dissertations

Particle variability at a Gulf Stream warm core ring/ shelf break front on 09 Nay 1985 was analyzed. Single particle measurements of fluorescence, perpendicular light scatter, and volume were made using a FACS Analyzer flow cytometer. Advantages and disadvantages of at-sea use of the instrument are described. To evaluate the flow cytometry data, individual particle data were compared with bulk phytoplankton and particle measurements. Abundance and size distributions of fluorescent and non-fluorescent particles indicated a convergence zone at the front while upwelling was likely within the ring perimeter. Variability in fluorescence (approximating chlorophyll A) and cell biovolume exposed regions of …


The Soils Of South Carrabin Research Station -Light Land Annex, Henry Smolinski, G G. Scholz Jun 1987

The Soils Of South Carrabin Research Station -Light Land Annex, Henry Smolinski, G G. Scholz

Resource management technical reports

No abstract provided.


Growth Rate Of Stony Corals Of Broward County, Florida: Effects From Past Beach Renourishment Projects, Richard E. Dodge, Broward County Erosion Prevention District Environmental Quality Control Board Jun 1987

Growth Rate Of Stony Corals Of Broward County, Florida: Effects From Past Beach Renourishment Projects, Richard E. Dodge, Broward County Erosion Prevention District Environmental Quality Control Board

Marine & Environmental Sciences Faculty Reports

The skeletal growth of hermatypic (reef-building) corals is a sensitive indicator of environmental conditions and perturbations. In particular, excessive sedimentation and turbidity act to depress coral growth because energy expenditure is required to remove sediment and because turbidity reduces light energy necessary for coral health and nutrition.

Normalized annual growth (linear skeletal extension) rates of Broward County, Florida reef-building corals were over 16 years (1985-1970). Star corals (Montastrea annularis) and brain corals (Diploria labyrinthiformis) were collected from each of four reef sites at two depths (9m and 18m). Collection areas were located in the vicinity of …


Case-Control Study Of Vitamin A Intake And Colorectal Cancer In Seventh-Day Adventists, John William Morgan Jun 1987

Case-Control Study Of Vitamin A Intake And Colorectal Cancer In Seventh-Day Adventists, John William Morgan

Loma Linda University Electronic Theses, Dissertations & Projects

Colorectal cancer is the second most common cause of cancer deaths in Americans; producing approximately 60,000 deaths in Americans each year. Studies of high and low risk populations have suggested a dietary etiology for colorectal cancer, although investigations of specific dietary factors have produced inconsistent results.

Population based studies of California Seventh-day Adventists demonstrate dietary variety regarding factors suspected as important in the etiology of colorectal cancer. These studies document a substantially reduced mortality and incidence from colorectal cancer in Seventh-day Adventists when compared to other California Populations. Although specific reasons for this difference remain obscure, the 'Unique lifestyle and …


Comparison Of Littoral And Limnetic Zooplankton Communities Of Lake Mead, Patrick Joseph Sollberger May 1987

Comparison Of Littoral And Limnetic Zooplankton Communities Of Lake Mead, Patrick Joseph Sollberger

Publications (WR)

Microfaunal communities were studied in littoral (inshore) and limnetic (offshore) areas of the lower basin in Lake Mead to compare species composition and abundance between the two zones. Planktonic forms (zooplankton) dominated inshore and offshore habitats and the occurrence of littoral species was low. Therefore, high similarity in zooplankton species composition was found among all sampling stations. This was perhaps due to two main factors: (i) the physical and chemical environment among the stations were very similar and (ii) the lack of aquatic vegetation in the littoral zone reduced the occurrence of littoral species.

Although species composition did not vary …


Program Abstracts, 99th Session, Iowa Academy Of Science, April 24-25, 1987, Iowa Academy Of Science Apr 1987

Program Abstracts, 99th Session, Iowa Academy Of Science, April 24-25, 1987, Iowa Academy Of Science

Iowa Academy of Science Documents

Presentation abstracts from the annual meeting of the Iowa Academy of Science


Control Of Ecosystem Processes By Prairie Dogs And Other Grassland Herbivores, James K. Detling, April D. Whicker Apr 1987

Control Of Ecosystem Processes By Prairie Dogs And Other Grassland Herbivores, James K. Detling, April D. Whicker

Great Plains Wildlife Damage Control Workshop Proceedings

Black-tailed prairie dogs in the mixed-grass prairie at Wind Cave National Park, South Dakota, create habitat patches characterized by altered species composition, lower standing crops of plants, but higher forage quality. Native wildlife species such as bison, pronghorn, and elk preferentially feed on these prairie dog colonies and likely derive nutritional benefits from doing so.


Efficacy Of Deferred Grazing In Reducing Prairie Dog Reinfestation Rates, Kelly A. Cable, Robert M. Timm Apr 1987

Efficacy Of Deferred Grazing In Reducing Prairie Dog Reinfestation Rates, Kelly A. Cable, Robert M. Timm

Great Plains Wildlife Damage Control Workshop Proceedings

Population growth of black-tailed prairie dogs (Cynomys ludovicianus) was studied in 1985 and 1986 at 20 prairie dog towns on short- and mixed-grass rangeland in western Nebraska, to determine the efficacy of 2 years deferred (May 1 - Sept. 1) grazing in reducing population growth rates following population reduction. In 1985, population growth measures on deferred sites were not significantly different from grazed sites, perhaps due to drought conditions. In 1986, natality and population growth (% increase in animals) were significantly lower on deferred sites than on sites grazed by livestock. Deferred sites studied both years showed significant …


Management Of Prairie Dog Populations In Wind Cave National Park, Richard W. Klukas Apr 1987

Management Of Prairie Dog Populations In Wind Cave National Park, Richard W. Klukas

Great Plains Wildlife Damage Control Workshop Proceedings

Since the late 1920's there have been periodic control programs on black-tailed prairie dogs in Wind Cave National Park. The most recent control effort, which began in 1982, resulted in the reduction of total dogtown acreage from 2,000 to 750 acres. Recent studies carried out within the park have provided managers with more soundly based justification for carrying out control programs. The same information also points to the importance of maintaining prairie dog populations at or above certain minimum levels and the need for integrating this control program with several of the other resource management programs being carried out in …


The Prairie Naturalist Volume 19, No. 1 March 1987 Mar 1987

The Prairie Naturalist Volume 19, No. 1 March 1987

The Prairie Naturalist

Paul B. Kannowski, Editor

Nikki R. Seabloom, Assistant Editor

Douglas H. Johnson, Book Review Editor

TABLE OF CONTENTS

ECOLOGY OF WHITE-TAILED DEER IN UPLAND PONDEROSA PINE HABITAT IN SOUTHEASTERN MONTANA ▪ G. L. Dusek

PRECISION AND BIAS OF A SUMMER AERIAL TRANSECT CENSUS OF PRONGHORN ANTELOPE ▪ S. H. Allen and J. M. Samuelson

ACTIVITY PATTERNS, MOVEMENTS, AND HOME RANGES OF PRAIRIE MINK ▪ T. W. Arnold and E. K. Fritzell

BRYOPHYTES OF THE SOUTH UNIT OF THEODORE ROOSEVELT NATIONAL PARK, NORTH DAKOTA ▪ C. L. Blaney and D. H. Norris

FALL FOOD HABITS OF WILD TURKEYS IN SOUTH CENTRAL …