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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


Attraction To Blood As A Factor In Tail-Biting By Pigs, David Fraser Apr 1987

Attraction To Blood As A Factor In Tail-Biting By Pigs, David Fraser

Abnormal Behavior Collection

Canvas models, about the size of a pig's tail, were impregnated with pigs' blood or left plain, and were presented to pigs for 12 days in a 2-choice preference test. The pigs showed large, consistent, individual differences in response: some pigs chewed the models continuously while others chewed only slightly; some chewed much more on the blood-covered model, while others showed no preference. On average, the pigs chewed considerably more on the blood-covered model than on the plain one. In a second experiment, pigs presented with a choice test involving a blood-covered and a plain model showed a significant increase …


Role Of Intracellular Ph In Muscle Fatigue, Joseph Mark Metzger, Robert H. Fitts Apr 1987

Role Of Intracellular Ph In Muscle Fatigue, Joseph Mark Metzger, Robert H. Fitts

Biological Sciences Faculty Research and Publications

Intracellular pH of in vitro diaphragm preparations was determined following low- (5 Hz, 1.5 min) and high- (75 Hz, 1 min) frequency stimulation, using glass microelectrodes of the liquid membrane type (pHm). Results were compared with values obtained by the standard homogenate technique (pHh). High- and low-frequency stimulation reduced peak tetanic tension to 21 ± 1 (SE) and 71 ± 2% of initial values, respectively. Peak tetanic tension returned to resting values after 10- to 15-min recovery from high- or low-frequency stimulation. Resting pHm was 7.063 ± 0.011 (n = 72), and after fatiguing …


Evaluation Of Two Methods For Estimating Belowground Production In The Great Dismal Swamp, Millie Symbula Apr 1987

Evaluation Of Two Methods For Estimating Belowground Production In The Great Dismal Swamp, Millie Symbula

Biological Sciences Theses & Dissertations

Two methods were used to estimate belowground production in a maple-gum stand in the seasonally flooded Great Dismal Swamp of Virginia. The first was an auger method which involved sequential core sampling. The second method was an implanted soil mass technique. Nylon mesh bags were filled with peat and buried at the study site. New growth into these implants was taken to be production.

Mean annual lateral root biomass and necromass to 40 cm, determined from soil cores, were 583 g·m-2 and 281 g·m-2, respectively. Production estimates for roots ≤ 5 mm in diameter, using soil cores, …


Mineralization Of Normal And Rachitic Chick Growth Cartilage: Vascular Canals, Cartilage Calcification And Osteogenesis, Irving M. Shapiro, Alan Boyde Mar 1987

Mineralization Of Normal And Rachitic Chick Growth Cartilage: Vascular Canals, Cartilage Calcification And Osteogenesis, Irving M. Shapiro, Alan Boyde

Scanning Microscopy

This paper reviews recent work in the authors' laboratories that has led to new observations and thoughts concerning the mineralization of normal and rachitic chick growth cartilage. The proximal tibial growth cartilages of normal and rachitic chicks were rapidly frozen and prepared for SEM and biochemical studies. Using a scanning microfluorimetric technique we showed that at the mineralization front of normal and rachitic cartilage there is an abrupt change in chondrocyte metabolism. Thus cells in this region exhibited an increase in NADH and oxidative metabolism. In rickets, there was a decrease in the reduced pyridine nucleotide content of each of …


The Allelopathic Effects Of Pokeweed (Phytolacca Americana) Berry Juice, Steven R. Parris Mar 1987

The Allelopathic Effects Of Pokeweed (Phytolacca Americana) Berry Juice, Steven R. Parris

Honors Theses

This paper is divided into three major sections. The first section is a limited overview of the field of allelopathy, from its origins to its potential future. Since the field of allelopathy is relatively young and there are only a very few texts on allelopathy available, much of this information is taken directly from journal articles. The second section reviews the publications concerning Phytolacca americana (pokeweed) and some of its close relatives, as well as information on a number of interesting and potentially useful compounds that have been isolated from them. The third section describes a series of laboratory experiments …


Genetic Parameters For First Lactation Milk Yields At Three Levels Of Herd Production, J. C. De Veer, L. Dale Van Vleck Mar 1987

Genetic Parameters For First Lactation Milk Yields At Three Levels Of Herd Production, J. C. De Veer, L. Dale Van Vleck

Department of Animal Science: Faculty Publications

A multivariate linear model was used to estimate sire variance and covariance components and residual variance components for first lactation milk yield and logarithms of yield at three herd production levels using Restricted Maximum Likelihood with the Expectation- Maximization algorithm. Data for four separate analyses were 305-d, mature equivalent first lactation milk records from cows sired artificially in the northeastern United States that freshened in 1970, 1971, 1976, and 1984. Respective numbers of records for each year were 42,618, 40,207, 33,581, and 34,196. Corresponding numbers of sires were 298, 289, 305, and 313. Herd production level was defined by mean …


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 …


Wpa News 15 (1987), World Pheasant Association Mar 1987

Wpa News 15 (1987), World Pheasant Association

Galliformes Specialist Group and Affiliated Societies: Newsletters

WPA News (March 1987), number 15

Published by the World Pheasant Association


The Aids Challenge: A Psychosocial Perspective, Madelyn S. Plotkin, Margaret Dietz Domanski Mar 1987

The Aids Challenge: A Psychosocial Perspective, Madelyn S. Plotkin, Margaret Dietz Domanski

Henry Ford Hospital Medical Journal

No abstract provided.


Effect Of Fertilizer Rates And Placement Practices On Yield Of Burley Tobacco, Kenneth L. Wells, G. D. Cantrill, J. L. Sims Mar 1987

Effect Of Fertilizer Rates And Placement Practices On Yield Of Burley Tobacco, Kenneth L. Wells, G. D. Cantrill, J. L. Sims

Agronomy Notes

Management of fertilizer practices in production of burley tobacco is very important in control of manganese (Mn) toxicity of the crop. In addition to the use of agricultural limestone, the use of fertilizers in the appropriate amounts, the appropriate kinds, and in the appropriate manner can strongly influence acidity in the rooting zone during the growth of burley. Studies of these effects have made up a major thrust of the University of Kentucky's research programs on fertility of burley, and have largely been conducted by J.L. Sims and his students during the past 15 years.


Fasting Plasma Amino Acids In Relation To Serum Lipids In Human Male Subjects, Helen G. Mendiola Mar 1987

Fasting Plasma Amino Acids In Relation To Serum Lipids In Human Male Subjects, Helen G. Mendiola

Loma Linda University Electronic Theses, Dissertations & Projects

The association of fasting plasma amino acids with serum lipids was studied in 23 healthy human male subjects with ages ranging from 31 to 62 years (45±9, mean± SD). There were 12 normocholesterolemic (serum cholesterol = 183±17 mg/dL) and 11 hypercholesterolemic (271±27 mg/dL) subjects. Venous blood samples were drawn three times at weekly intervals. Plasma amino acids were determined by ion-exchange chromatography, and serum cholesterol and triglycerides by enzymatic methods. Hypercholesterolemic subjects had significantly higher lysine and lower serine levels than normocholesterolemic subjects (p < .05). Serum cholesterol levels were positively correlated with plasma levels of lysine, ornithine and the lysine/arginine ratio (p < .04); and negatively correlated with phenylalanine and urea (p < .05). Serum triglyceride levels were positively correlated with plasma levels of lysine, glutamic acid, and valine (p <. 02); and negatively correlated with serine, glutamine, and asparagine (p < .04). These results add support to the hypothesis that specific plasma amino acids are associated with the metabolism of serum lipids.


Feeding Alfalfa To South Carolina Dairy Herds, Fred E. Pardue, Terry Sudduth Feb 1987

Feeding Alfalfa To South Carolina Dairy Herds, Fred E. Pardue, Terry Sudduth

Kentucky Alfalfa and Stored Forage Conference

The nutritional value of alfalfa hay is important if it is to be used competitively with other feedstuffs in rations being fed to South Carolina Dairy Herds. Excellent quality hay has high nutrient concentration, digestibility and intake. The appearance of good physical characteristics of alfalfa hay as well as other hays and forages along with the knowledge of harvest dates, stages of maturity, and other conditions are not enough and can be deceiving. Therefore, forage testing is crucial and very important.


Evaluating Alfalfa Grazing — Dollars And Cents, Robert N. Barnes Feb 1987

Evaluating Alfalfa Grazing — Dollars And Cents, Robert N. Barnes

Kentucky Alfalfa and Stored Forage Conference

Returns on many Kentucky farms are declining due to reduced tobacco and feedgrain income. This fact, coupled with traditionally low (or negative) returns from typical cow/calf beef enterprises, has been associated with interest in alternative crop and livestock production systems. Alfalfa produced as a cash crop is increasing and many farmers are realizing substantial returns. In the Central Kentucky Area, many farmers have been stimulated to produce alfalfa since demand for high quality hay by horse farms has been strong. As interest in alfalfa is renewed, other farms have begun to introduce intensive or controlled grazing techniques in order to …


Aspects Of Selection For Performance In Several Environments With Heterogeneous Variances, D. J. Garrick, L. Dale Van Vleck Feb 1987

Aspects Of Selection For Performance In Several Environments With Heterogeneous Variances, D. J. Garrick, L. Dale Van Vleck

Department of Animal Science: Faculty Publications

Dairy cattle evaluation schemes routinely assume homogeneous variance with respect to environment. Increasing evidence suggests the presence of systematic changes in variance components associated with mean level of performance. Best linear unbiased prediction procedures that account for heterogeneity are reviewed. The consequences of incorrectly assuming homogeneity for evaluation are demonstrated for a progeny test and an artificial breeding program that screens dams of sires from heterogeneous populations. Selection assuming homogeneity can be very efficient when heritability, and therefore accuracy of selection, is greatest in the more variable environment. Conversely, appreciable reduction in response results when heritability is greater in the …


Coccidian Parasites (Apicomplexa: Eimeriidae) From Insectivores. Iii. Seven New Species In Shrews (Soricidae: Soricinae) From Canada, Japan, And The United States, Lynn Ann Hertel, Donald W. Duszynski Feb 1987

Coccidian Parasites (Apicomplexa: Eimeriidae) From Insectivores. Iii. Seven New Species In Shrews (Soricidae: Soricinae) From Canada, Japan, And The United States, Lynn Ann Hertel, Donald W. Duszynski

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Since May 1979, 458 shrews (Blarina sp. and Sorex spp.) representing 20 species collected in Canada, Japan, and the United States were examined for coccidia; 110 (24%) had oocysts in their feces, including 8 of 21 (38%) B. brevicauda from Massachusetts, Ohio, Pennsylvania, and Vermont; 2 of 7 (29%) S. caecutiens from Hokkaido and Honshu; 14 of 63 (22%) S. cinereus from Colorado, New Mexico, Pennsylvania, Vermont, Manitoba, and Ontario; 3 of 7 (43%) S. fontinalis from Pennsylvania; 11 of 16 (69%) S. fumeus from Massachusetts, Minnesota, Pennsylvania, Vermont, and Ontario; 1 of 4 (25%) S. haydeni from Minnesota; …


Effects Of Body Condition On Reproductive Performance Of Range Beef Cows, R.J. Pruitt, P.A. Momont Jan 1987

Effects Of Body Condition On Reproductive Performance Of Range Beef Cows, R.J. Pruitt, P.A. Momont

South Dakota Beef Report, 1987

Simnental-Angus crossbred cows were fed differing Levels of nutrition from December to May in each of 3 years to create a wide range in cow body condition or fleshiness at the beginning of the calving season (beginning mid-March) and when turned to summer pasture (early May) 1 month prior to the beginning of the breeding season (early June). Cows that were fleshier in March, May or June cycled earlier. Cows that were fleshier at the beginning of the breeding season calved earlier the following years. For cows that calved Late in the calving season, body condition prior to calving, in …


Intsormil Annual Report 1987, John M. Yohe, Timothy T. Schilling Jan 1987

Intsormil Annual Report 1987, John M. Yohe, Timothy T. Schilling

INTSORMIL Impacts and Bulletins

The Sorghum/Millet CRSP was initiated on July 1, 1979. This annual report covers the activities for program Year 8. Eight years of experience have reaffirmed the need for this type of research program aimed at relieving the constraints to improved sustainable sorghum/millet production in developing countries. The emphasis by the CRSP on development of collaborative linkages with national sorghum/millet research programs has been unique. Significant contributions have been made toward resolving constraint problems and enhancing the national program capability by strengthening its human resource base as well as the national institutional capability to conduct collaborative research. Thus, the CRSPs present …


The Effectiveness Of Lime-Based Amendments And Bauxite Residues At Removing Phosphorus From Piggery Effluent, D. M. Weaver, G. S. P. Ritchie Jan 1987

The Effectiveness Of Lime-Based Amendments And Bauxite Residues At Removing Phosphorus From Piggery Effluent, D. M. Weaver, G. S. P. Ritchie

Food Science and Nutrition

Piggery effluent may contribute to the eutrophication of waterways, if it is not treated before disposal, because of high levels of phosphorus. Limes and red muds (a residue from bauxite refining) were used to remove phosphorus from piggery effluent (41 mg litre-1 total P). Lime-based amendments were more effective than the red muds at removing phosphorus when compared at the same liquid: solid ratios. Based on laboratory data, the cost of treating effluent increased rapidly as the final required phosphorus concentration decreased to less than 4 mg litre-1. Kiln dust was the cheapest amendment tested down to …


To The Deep Reef And Beyond, Charles Messing Jan 1987

To The Deep Reef And Beyond, Charles Messing

Marine & Environmental Sciences Faculty Books and Book Chapters

No abstract provided.


The Tolerance Of Legumes To Broadleaf Herbicides., P. Stewart, L. Mann Jan 1987

The Tolerance Of Legumes To Broadleaf Herbicides., P. Stewart, L. Mann

Experimental Summaries - Plant Research

Trial 87KA52

The control of broadleaf weeds in leguminous pasture is of major concern because of the ability of these weeds to compete strongly with the leguminous plants. The presence of broadleaf weeds in pasture reduces the pastures nutritional value as well as total nitrogen fixation. There are many herbicides which are available to control broadleaf weeds, but most of these are registered for use in cereals. The amount of tolerance that leguminous pasture plants show to many of these herbicides and herbicide mixes is not known.

The experiments were designed to screen a large number of herbicides for legume …


Cyanonews (Vol. 3, No. 1, April 1987), Jeff Elhai Jan 1987

Cyanonews (Vol. 3, No. 1, April 1987), Jeff Elhai

CyanoNews

CyanoNews was a newsletter that served the cyanobacteriological community from 1985 to 2003, with content provided by readers (sort of a blog before there were blogs). The newsletter reported new findings from the lab, summaries of recent meetings (often provided by graduate students and post-docs entering the field), positions sought or available, life transitions, a compendium of recent cyanobacteria-related articles, and other items of interest to those who study cyanobacteria.


Sdsu Dairy Digest, South Dakota State University Dairy Club Jan 1987

Sdsu Dairy Digest, South Dakota State University Dairy Club

Dairy Digest

No abstract provided.


1987 South Dakota Beef Report, Department Of Animal And Range Sciences, South Dakota State University, Agricultural Experiment Station, South Dakota State University, Cooperative Extension Service, South Dakota State University Jan 1987

1987 South Dakota Beef Report, Department Of Animal And Range Sciences, South Dakota State University, Agricultural Experiment Station, South Dakota State University, Cooperative Extension Service, South Dakota State University

South Dakota Beef Report, 1987

This is the complete 1987 South Dakota Beef Report.


Comparison Of The Diet, Feeding Behavior, And Habitat Use Of Mallards (Anas Platyrhynchos) And Black Ducks (Anas Rubripes), Michael J. Bennett Jan 1987

Comparison Of The Diet, Feeding Behavior, And Habitat Use Of Mallards (Anas Platyrhynchos) And Black Ducks (Anas Rubripes), Michael J. Bennett

Biology Honors Papers

No abstract provided.


Views On Biotechnology, George B. Rathmann Jan 1987

Views On Biotechnology, George B. Rathmann

Journal of the Minnesota Academy of Science

No abstract provided.


Biotechnology In Agriculture: An Overview, C. Eugene Allen Jan 1987

Biotechnology In Agriculture: An Overview, C. Eugene Allen

Journal of the Minnesota Academy of Science

No abstract provided.


Influence Of Delignifying Agents On Tissue Structure In Bermudagrass Stems, D. E. Akin, L. L. Rigsby, F. E. Barton, P. Gelfand, D. S. Himmelsbach, W. R. Windham Jan 1987

Influence Of Delignifying Agents On Tissue Structure In Bermudagrass Stems, D. E. Akin, L. L. Rigsby, F. E. Barton, P. Gelfand, D. S. Himmelsbach, W. R. Windham

Food Structure

Permanganate, dioxane, ozone, and hydrogen peroxide, which delignify plant materials, were evaluated for their disruptive action on plant structure, the ir modification of histological reactions for Iignins, and their change in in vitro digestibility by rumen microorganisms of yollng-Tsecond internode from top) and old (fourth and fifth internodes) bermudagrass stems. Epidermis, sclerenchymaring, and vascular tissue (except phloem) gave positive reactions with acid phloroglucinol (AP) or chlorinesulfite (CS) in all samples , whereas cortex and parenchyma in older stems gave a positive reaction with CS. Treatment with delignifying agents reduced the reactions for lignin, with permanganate- treated tissues having the least …


Project Reports 1987-1991, Various Authors Jan 1987

Project Reports 1987-1991, Various Authors

Annual Reports

No abstract provided.


Evaluation Of Risk Factors Leading To Soil Destabilisation On The South Coastal Sandplain Of Western Australia, R V R Gwynn, P A. Findlater, J R. Edwards Jan 1987

Evaluation Of Risk Factors Leading To Soil Destabilisation On The South Coastal Sandplain Of Western Australia, R V R Gwynn, P A. Findlater, J R. Edwards

Resource management technical reports

The problems of wind erosion in part of the south coast of Western Australian sandplain area were described previously (Gorddard et al, 1981) with 7.3 per cent of cleared and 18.3 per cent of the cropped area showing evidence of sand blasting. Department of Agriculture trials have shown that the loss of the top four millimetres of top soil from pastured paddocks can reduce following crop yields by up to 20 per cent (Marsh and Carter, 1983). Animal production problems associated with wind erosion of soils have not been quantified, but a number of problems such as reduced carrying capacity …