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Levels Of Calcium And Phosphorus For Growing-Finishing Swine, G. W. Libal, E. R. Peo, Jr., R. P. Andrews, P. E. Vipperman, Jr. Jan 1969

Levels Of Calcium And Phosphorus For Growing-Finishing Swine, G. W. Libal, E. R. Peo, Jr., R. P. Andrews, P. E. Vipperman, Jr.

Department of Animal Science: Faculty Publications

The calcium and phosphorus requirements of growing-finishing swine have not been satisfactorily resolved. Recently it was suggested that levels of calcium and phosphorus needed in diets of growing-finishing (G-F) swine for optimum growth and feed conversion may be different from those needed for optimum bone development (Miller et al., 1960; Lloyd et al., 1961; Rutledge et al., 1961; Combs et al., 1966). The problem of determining calcium and phosphorus requirements is further magnified by the observation of Chapman et al. (1955) that G-F swine do not utilize plant phosphorus as efficiently as inorganic phosphorus. In …


Cropping Investigations, M L. Poole Jan 1969

Cropping Investigations, M L. Poole

Experimental Summaries - Plant Research

The Mexican semi-dwarf wheat varieties have performed very well under high fertility conditions overseas. There is considerable evidence that they have greater potential for yield than the Australia spring varieties because of greater number of flowers set per spikelet. In this trial Falcon and Pitic were grown under almost optimal conditions for dryland wheat growing in Western Australia. The trial was planted early (21st May) into a completely weed free seedbed. Nutrition was near optimal. Seasonal conditions were near perfect. Grain yields were extremely high for Western Australia. Pities reputed superior potential for yield/unit area was not expressed under these …


Indoor Versus Outdoor Calf Rearing At Three Weaning Ages, Larry J. Jorgenson Jan 1969

Indoor Versus Outdoor Calf Rearing At Three Weaning Ages, Larry J. Jorgenson

Electronic Theses and Dissertations

In order to be profitable, a dairy herb must have good heifers to meet replacement needs. According to USDA (51), these needs are substantial because 25% of the cows in an average herd must be replaced each year as they no longer return a profit. Meeting these herd replacement needs has long been a serious problem of the dairyman. Nation-wide calf loss estimates ranged between 8 and 25% with an estimated annual loss to the industry of $50 million (10). South Dakota dairymen are not immune to these mortality losses and some studies (28, 52) indicate that their losses may …


Metabolic Responses Of White Rats To Glucose Or Fructose Fed With Two Safflower Oils Containing Different Proportions Of Fatty Acid, Paula Lynn Yates Jan 1969

Metabolic Responses Of White Rats To Glucose Or Fructose Fed With Two Safflower Oils Containing Different Proportions Of Fatty Acid, Paula Lynn Yates

Journal of the Arkansas Academy of Science

No abstract provided.


Vitamin A In Beef Cattle Feeding, L.B. Embry, L.J. Kortan Jan 1969

Vitamin A In Beef Cattle Feeding, L.B. Embry, L.J. Kortan

Agricultural Experiment Station Animal Husbandry Pamphlets

Vitamin A is essential for all cattle. The vitamin does not occur naturally in feeds of plant origin. Many cattle are never fed vitamin A as such but do not develop a deficiency of the vitamin. The reason for this is that many feeds (pasture, good quality hay, silage, and yellow com) furnish carotene which is converted to vitamin A in the animal body.


Higher Stocking Rates For Cattle On Irrigated Pasture : A Report From Wokalup Research Station, Maurice C. Cullity Jan 1969

Higher Stocking Rates For Cattle On Irrigated Pasture : A Report From Wokalup Research Station, Maurice C. Cullity

Journal of the Department of Agriculture, Western Australia, Series 4

The possibility that higher cattle stocking rates than those commonly used could be economical was suggested by the results of a stocking rate trial at Wokalup Research Station


Superphosphate For Wheatbelt Pastures : Rates Of Application, Walter Jacob Cox Jan 1969

Superphosphate For Wheatbelt Pastures : Rates Of Application, Walter Jacob Cox

Journal of the Department of Agriculture, Western Australia, Series 4

BECAUSE Western Australian soils are low in phosphorus, frequent applications of superphosphate are required for both crop and pasture production. The recommended rates are determined from the results of field experiments that test different quantities of super and measure the extra yield.

This article discusses the recommended rates of superphosphate in relation to soil type and superphosphate history. Methods of application and time of topdressing are also discussed.


Housing Pigs, P Mcnamara Jan 1969

Housing Pigs, P Mcnamara

Journal of the Department of Agriculture, Western Australia, Series 4

THERE are many designs for pig houses and much will depend on individual circumstances which is best in any particular case.


Growth Patterns In Bacillus Stearothermophilus, Harold B. Betton Jan 1969

Growth Patterns In Bacillus Stearothermophilus, Harold B. Betton

Journal of the Arkansas Academy of Science

No abstract provided.


More Butterfat Per Acre At Denmark Research Station, Department Of Agriculture, Western Australia Jan 1969

More Butterfat Per Acre At Denmark Research Station, Department Of Agriculture, Western Australia

Journal of the Department of Agriculture, Western Australia, Series 4

STOCKING rates on dairy farms are generally too low and can be substantially increased, but unfortunately there is no satisfactory measurement to indicate the potential of a particular pasture or environment.

A trial carried out on Denmark Research Station in 1966-67, to obtain information on carrying capacity of a dryland kikuyu-subterranean clover pasture.


Wheatbelt Trace Element Nutrition 1969, J W. Gartrell Jan 1969

Wheatbelt Trace Element Nutrition 1969, J W. Gartrell

Experimental Summaries - Plant Research

1. Rates of Copper and Zinc on Wheat. 2. Rates and Sources of Zinc on Wheat: 3..Zinc Spray Treatments on Wheat.


List Of Experiment Programmes 1969 -1970, Department Of Agriculture And Food, Western Australia Jan 1969

List Of Experiment Programmes 1969 -1970, Department Of Agriculture And Food, Western Australia

Experimental Summaries - Plant Research

T. Albertsen, maintenance phosphorus and sulphur, continuous cropping with NPS, sulphur status in high rainfall areas. J. Cripps, (jointly with B Luren), experiments at Stoneville research station and on growers’ properties. A.C. Devitt, replacement of legume pasture, evaluation of Midland b, competitive ability of some sub clovers. Evaluation of Dinninup 3. Evaluation of Tornafield medic 1967. Evaluation of some medics 1968. Evaluation of Northam A crossbreds. Effect of phosphate on growth of medics 1968. Effect of Urea on growth of subclover on new land. Effect of Urea on established legume pastures. Pasture species establishment and persistence. Evaluation of pasture species …


Gaseous Exchange In Crop Stands, Edgar Lemon Jan 1969

Gaseous Exchange In Crop Stands, Edgar Lemon

Department of Agronomy and Horticulture: Faculty Publications

Man through the ages has evolved a strategy, albeit empirical, of manipulating the environment and the plant to his advantage. Practices such as fertilizing the soil, irrigation, weed control, and plant breeding and selection are common. Nonetheless, concentrated and coordinated efforts to understand the mechanisms controlling the whole soil-plant- atmosphere continuum is a new approach to finding new ways to favorably manipulate the whole system as well as predict response.
Conceptually and experimentally it has proven advantageous to view the total system in terms of energy, momentum, and mass exchange. This makes sense because in the first instance the foundations …


Physiological Significance Of Internal Water Relations To Crop Yield, R. O. Slatyer Jan 1969

Physiological Significance Of Internal Water Relations To Crop Yield, R. O. Slatyer

Department of Agronomy and Horticulture: Faculty Publications

The overall effects of water deficits on crop yield are known to everybody. Moderate water deficiencies can result in stunting, distorted development, and much reduced crop yields, and prolonged drought can cause complete crop failure.
Despite these visible symptoms of deficiency, a clear and unambiguous statement as to the effect of deficits on crop yield is difficult to make, for a variety of reasons. Firstly, despite the importance of the phenomenon to agriculture in most of the food producing countries of the world, relatively little attention has been devoted to its water deficits. Secondly, and in part this is a …


Physiological Aspects Of Crop Yield (Frontmatter), Jerry D. Easton, Francis A. Haskins, C. Y. Sullivan, C. H. M. Van Bavel Jan 1969

Physiological Aspects Of Crop Yield (Frontmatter), Jerry D. Easton, Francis A. Haskins, C. Y. Sullivan, C. H. M. Van Bavel

Department of Agronomy and Horticulture: Faculty Publications

Foreword
Preface
Contributors
Contents

This volume is the outgrowth of an international symposium held at Lincoln, Nebraska, January 20-24, 1969. It was sponsored by the University of Nebraska in cooperation with the American Society of Agronomy and the Crop Science Society of America with partial financing by the Rockefeller Foundation and the International Biological Program.
The symposium planning committee was broadly based and was able to bring specialists from many parts of the world to the conference. Thus, the technical presentations were drawn from outstanding authorities backed up by a clear perspective of social needs. This was a happy combination …


Germ Plasm Manipulations Of The Future, George Sprague Jan 1969

Germ Plasm Manipulations Of The Future, George Sprague

Department of Agronomy and Horticulture: Faculty Publications

The topic, Germ Plasm Manipulations of the Future, could cover the entire field of genetics. This would be a very difficult assignment and, were I willing to attempt it, one that might not best serve the specific purpose of this symposium. I shall take a much more restrictive view and consider only certain phases of genetics which, in my opinion, will become of increasing importance in crop improvement.
In the period since 1900 genetics has achieved close and reciprocally productive relations with several fields of science. A partial listing of these would include genetics and cytology to yield cytogenetics; genetics …


Development, Differentiation, And Yield, John Heslop-Harrison Jan 1969

Development, Differentiation, And Yield, John Heslop-Harrison

Department of Agronomy and Horticulture: Faculty Publications

The task of reviewing some of the ways development and differentiation may act as determinants of economic yield would be much simpler had knowledge advanced to a point where the basic principles concerned in the control of these processes in eukaryotic organisms were clear. Unfortunately, this stage has not yet been reached. There is no shortage of schemes and hypotheses to set beside a mountain of observational and experimental data, but the unifying thread which might allow us to pick out the significant and reject the irrelevant in any particular context is still lacking. What is incontestable is that development …


Plant Morphology And Stand Geometry In Relation To Nitrogen, Robert F. Chandler Jr. Jan 1969

Plant Morphology And Stand Geometry In Relation To Nitrogen, Robert F. Chandler Jr.

Department of Agronomy and Horticulture: Faculty Publications

During the past decade, the importance of plant morphology and spacing in relation to nitrogen responsiveness in terms of crop yield has been increasingly recognized, particularly in the case of the cereal grains.
It is the purpose of this paper to present examples of experimental results obtained by rice research workers which support certain significant principles. Although this treatise will be confined to the rice plant (Oryza sativa L.),as Wittwer (1968) points out, the principles elucidated are applicable to many other crops, and particularly to the small grains, such as wheat (Triticum aestivum L.), oats (Avena sativa …


Physiological Responses To Nitrogen In Plants, Yoshio Murata Jan 1969

Physiological Responses To Nitrogen In Plants, Yoshio Murata

Department of Agronomy and Horticulture: Faculty Publications

Recent advances in crop physiology have given us some clues for analysis of the complex relationships of environmental factors, cultural conditions and genetic factors to crop yield. However, in order to accomplish this analysis, it is quite necessary to have concrete knowledge about the causal relationships and the time sequence of the processes of yield-formation.
In grain crops, the process of yield-formation may be divided into the following three phases:
1) Formation of organs for nutrient absorption and photosynthesis,
2) Formation of flower organs and "yield-container," and
3) Production, accumulation and translocation of "yield-contents."
The effect of nitrogen, which has …


Interrelationships Among Photosynthesis, Respiration, And Movement Of Carbon In Developing Crops, Volkmar Stoy Jan 1969

Interrelationships Among Photosynthesis, Respiration, And Movement Of Carbon In Developing Crops, Volkmar Stoy

Department of Agronomy and Horticulture: Faculty Publications

From the preceding lectures we have learned a great deal about how external conditions may influence various internal physiological processes within plants, and it therefore appears appropriate to consider briefly how these processes influence one another and also the manner in which they relate to yield. The main processes of interest in this connection are photosynthesis, respiration, and carbon assimilate translocation; but aspects of growth, development, mineral nutrition, etc., will also be considered when relevant.


The Identification Of Cis-Ii, I2-Methylene-2-Hydroxyoctadecanoic Acid From Thiobacillus Thiooxidans, H. W. Knoche, J. M. Shively Jan 1969

The Identification Of Cis-Ii, I2-Methylene-2-Hydroxyoctadecanoic Acid From Thiobacillus Thiooxidans, H. W. Knoche, J. M. Shively

Department of Biochemistry: Faculty Publications

A polar fatty acid has been observed as a component of an

ornithine-containing lipid of Thiobacillus thiooxidans. A

comparison of thin layer chromatographic mobilities of reference

compounds to those of the natural acid and its derivatives

suggested that the acid was a 2-hydroxy fatty acid.

The presence of a cyclopropane function in the acid was

indicated by l4e-Iabeling experiments and infrared spectroscopy.

Mass spectrometry of the methyl ester and the acetylated

methyl ester of the natural acid provided a molecular

weight for the acid. Equivalent chain lengths were determined

for the natural acid, the acid obtained by oxidative

decarboxylation of …


Axenic Ovarial Explants From The Marine Nematode Deontostoma Californicum On Culture Media, D. R. Viglierchio, Armand R. Maggenti, R. N. Johnson Jan 1969

Axenic Ovarial Explants From The Marine Nematode Deontostoma Californicum On Culture Media, D. R. Viglierchio, Armand R. Maggenti, R. N. Johnson

Harold W. Manter Laboratory of Parasitology: Faculty Publications

The gonads of Deontostoma californicum were isolated from the organismal environment by dissection. In an attempt to approximate the in vivo condition and to maintain in vitro architecture and function ten media recommended for the culture of insect cells or organs were tested. The media were prepared in two series: one according to published recommendations and the second substituting filtered seawater for the inorganic salts and distilled water. Media were prepared as both liquid and gel (agar) with and without antibiotics. Whole animals and eggs were placed on the same culture media series as the ovarial explants. Ovarial explant reaction …


Systems Analysis Of Natural Resources And Crop Production, Marion Clawson Jan 1969

Systems Analysis Of Natural Resources And Crop Production, Marion Clawson

Department of Agronomy and Horticulture: Faculty Publications

Human history is a seamless web; every event has its antecedents, its contemporaries, and its consequences. Each event arises out of the past, each is associated with other events at the time, and each leads to new events, in an endless chain. Indeed, there is difficulty in isolating any single event; when did it begin, what are its boundaries, when did it end? These are some of the problems of the social scientist generally, and of the historian in particular.
Nature is equally a seamless web. Every natural process or event has its cause or antecedent, each takes place within …


Predicted Versus Measured Production Differences Using Summer Air Conditioning For Lactating Dairy Cows, Leroy Hahn Jan 1969

Predicted Versus Measured Production Differences Using Summer Air Conditioning For Lactating Dairy Cows, Leroy Hahn

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Predicted summer production losses were made for Holstein cows in three widely separated locations in the United States where field investigations of air conditioning for dairy barns have been completed. These losses, based on a functional relationship developed from Missouri Climatic Laboratory data and local climatological data, were compared to the measured losses at each location. Correlation of losses for Holstein cows varied from excellent in northern Ohio to good in southern Louisiana and central Missouri. Variations due to hotter- or cooler-than-normal summer seasons and level of production were reasonable at all locations.


Mammalian Cell Genetics I. Selection And Characterization Of Mutations Auxotrophic For L-Glutamine Or Resistant To 8-Azaguanine In Chinese Hamster Cells In Vitro, E. Virginia Merriam Jan 1969

Mammalian Cell Genetics I. Selection And Characterization Of Mutations Auxotrophic For L-Glutamine Or Resistant To 8-Azaguanine In Chinese Hamster Cells In Vitro, E. Virginia Merriam

Biology Faculty Works

No abstract provided.


A Preliminary Survey Of The Algal Flora Found On Tree Bark In East-Central Illinois, Marion E. Rohlinger Jan 1969

A Preliminary Survey Of The Algal Flora Found On Tree Bark In East-Central Illinois, Marion E. Rohlinger

Masters Theses

No abstract provided.


The Functional Morphology Of Axiothella Rubrocinta (Johnson), Robert Bernard Spies Jan 1969

The Functional Morphology Of Axiothella Rubrocinta (Johnson), Robert Bernard Spies

University of the Pacific Theses and Dissertations

The family Maldanidae is a group of sedentary polychaetes having a cylindrical body with elongate, but relatively few segments. The prostomium has a dorsal pair of nuchal organs and may have eye-spots ventrally; true appendages are absent. The mouth opens ventrally on the peristomium and has an extrusible sacciform proboscis. The pygidium may be plate-shaped, funnel shaped with an internal cone, or simply cone-shaped. All maldanids inhabit tubes of sand or mud, and subject to the limitations and advantages of this habjtat.


A Study Of The Effects Of Sitosterol Ingestion On The Serum Cholesterol Concentrations Of Two Genetically Different Strains Of Laboratory Mice, Marie Nichols Goldberg Jan 1969

A Study Of The Effects Of Sitosterol Ingestion On The Serum Cholesterol Concentrations Of Two Genetically Different Strains Of Laboratory Mice, Marie Nichols Goldberg

University of the Pacific Theses and Dissertations

A possible interrelationship between serum cholesterol level and atherosclerosis has long interested investigators in the fields of physiology and biochemistry. Cholesterol is found in very high concentrations in the plaques that occlude coronary arteries in man and laboratory animals. It is generally agreed that hypercholesterolemia favors the appearance of atherosclerotic lesions.1<1

In recent years, much information has been accumulated regarding the factors which affect the serum cholesterol level. Exact and detailed biochemical mechanisms are still not clearly understood. However, it has been demonstrated that the serum cholesterol levels of man and several experimental animals can be lowered significantly by …


The Effects Of Light Quality And Culture Age On Protein Synthesis In Oscillatoria Species , Jon Chesnut Jan 1969

The Effects Of Light Quality And Culture Age On Protein Synthesis In Oscillatoria Species , Jon Chesnut

Master's Theses

No abstract provided.


Enzyme Histochemistry Of The Human Carotid Body, Gerald Fine, Pablo Enriquez, Azorides R. Morales Dec 1968

Enzyme Histochemistry Of The Human Carotid Body, Gerald Fine, Pablo Enriquez, Azorides R. Morales

Henry Ford Hospital Medical Journal

Histochemical enzymatic survey of 25 "normal" human carotid bodies removed at autopsy from patients three days to 83 years of age revealed a variety of oxidative and hydrolytic enzymes in the lobular and interlobular cells. The intensity of the reactions was greater in the lobular cells. Acid phosphatase was the only enzyme that was limited to the cells comprising the lobules.