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The Role Of Light In The Regulation Of Cyclical Estrous Activity In Sheep, M. T. Clegg, H. H. Cole, W. F. Ganong

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

The widespread existence of biological clocks among animals is documented by a considerable body of evidence. Recently Farner (13) has reviewed this subject covering information on a large variety of animals. In this paper an attempt will be made to restrict most of the discussion to sheep. Experimental data from other species, however, will be cited when it can be usefully related to an understanding of the mechanisms controlling seasonal breeding activity in this species. As far as present knowledge is concerned, the factors regulating or at least monitoring annual physiologic cycles appear to depend greatly upon the influence of …

Comments And Conclusions Concerning Studies On Estrous Control In Domestic Animals, H. H. Cole

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

Let me allay at once any apprehension you may have that I am about to recapitulate all that has been said during the past two days. Redundancy at this time would merely accentuate your current soporific state. Thus I shall take advantage of the prerogative of seniority to modify the title of my talk to "Comments and conclusions concerning studies on estrous control in domestic animals."

Evaluation Of Methods For Controlling The Estrous Cycle, William Hansel

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

Truly effective estrous cycle synchronization techniques are of great potential value to commercial producers of beef and dairy cattle, sheep, and swine. Many commercial beef cattlemen recognize the merits of using outstanding sires through artificial insemination (AI) to produce greater numbers of faster gaining cattle having the most desirable carcass characteristics. The relatively high heritability of feedlot gains makes this idea particularly attractive. Nevertheless, progress in attaining this goal has been rather slow, mainly because of the practical problems involved in breeding range cattle artificially and the low conception rates frequently obtained. Methods for cycle regulation compatible with the most …

Hormonal Control Of Reproductive Activity In The Ewe, J. F. Wagner

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

There are many advantages which result from synchronizing the estrous period in a ewe flock. In situations where the ewes are not hand bred to the ram, the synchronization of estrus makes the application of artificial insemination (AI) techniques more efficient. Detection of estrus usually is more reliable in a synchronized flock. Only 3 to 4 days are needed to detect estrus in 90 percent of a synchronized flock, whereas 16 to 18 days are normally required. This allows the AI technician to plan the number of breedings and have semen available. When hormones are given in the feed, an …

Phytotoxic Substances From Soil Microorganisms And Crop Residues, T.M. Mccalla, F.A. Haskins

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

The role of organic matter in the growth of plants has been a subject of much investigation and controversy since the sixteenth century. During the early era, decomposition of plant residues and green and animal manures provided a primary source of minerals for plant growth. In addition, beneficial effects on soil structure and water-holding capacity were attribute to the presence of organic matter. With the development of agricultural chemistry culminating in the work of Liebig in the nineteenth century, it was discovered that plants could make satisfactory growth in the absence of added organic matter if suitable kinds and amounts …

A Study Of Puccinia Graminis And Cronartium Ribicola, Duane W. Hughes

Graduate Student Research Papers

It was the purpose of this study (1) to review the literary history of rusts in the United States and in the Northwest in particular, ( 2) to learn where rusts generally are found geographically, (3) to gain further information regarding the etiology of wheat rust (Puccinia graminis tritici), of white pine blister rust (Cronartium ribicola) and to become enlightened on other rusts, (4) to learn ways of controlling the two rusts, black stem rust of wheat and white pine blister rust, and to gain an appreciation of the economic importance of rust prevention.

The Inhibition Of Seedling Growth By Crop Residues In Soil Inoculated Wlth Penicillium Urticae Bainer, D. E. Behmer, T. M. Mccalla

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

In the Great Plains area of the United States, stubble-mulch practices have been widely used in the control of soil erosion by wind or water. Although this method of leaving crop residue on the surface has been very effective in combating erosion, depressed plant growth and reduced grain yield have often occurred in wet years. Similar growth problems have been observed during unseasonably cool, wet springs in field experiments at Lincoln, Nebraska. Because increased numbers of certain micro-organisms occur immediately beneath a decomposing surface mulch, the production of phytotoxic compounds under these conditions may well have been associated with the …

Microorganisms And Soil Structure, T. M. Mccalla, F. A. Haskins

Department of Agronomy and Horticulture: Faculty Publications

SUMMARY

Good stable soil structure is valuable for promoting the growth of plants and micro-organisms by permitting enhanced aeration and water penetration and by decreasing erosion under some conditions.

Micro-organisms influence water percolation through the soil. They may plug up soil pores with byproducts of growth and reduce water percolation. On the other hand, if a soil containing a large amount of microbial products is stirred and allowed to dry, then the percolation may be high.

Micro-organisms are involved in stabilizing soil structure by their products of decomposition and their cellular binding material, such as mycelia. Microorganisms differ greatly in …

Pensternon In Your Garden, Glenn Viehmeyer

Department of Agronomy and Horticulture: Faculty Publications

A new race of hardy perennials is beginning to appear in American gardens. These are the penstemons, a genus of plants closely related to the familiar snapdragon, which may become important ornamentals as they become better known to gardeners. The purpose of this bulletin is to show the possibility of the genus as an ornamental and to suggest species and species hybrids of possible value to Great Plains gardeners; to provide information about propagation and culture; and to encourage gardeners to engage in penstemon breeding as an avocation.

A Study Of The Effect Of Three Nutrients On The Growth Of Tomatoes, Walter B. Stone

Biology ETDs

Studies of the various phases of plant growth are becoming more and more important to plant physiologists. Many such studies have been conducted for economic reasons to obtain increased production. In this investigation, fruit production and quality have been considered important, but have been placed second in interest to the effect certain nutrients may have on plant development during growth.

Most experiments of this type have been concerned with nutrient deficiencies. The writer has attempted in this experiment to use nutrient elements in excess and observe the effects produced during progressive phases of plant growth. Single elements, nitrogen, phosphorus, and …

Bulletin No. 381 - The Organization And Structure Of Egg Marketing In Utah, Roice H. Anderson

UAES Bulletins

Sale of eggs is one of the major sources of farm income in Utah. In 1954 egg receipts represented 8 percent of the farm cash income. This was the lowest percentage since 1929; receipts reached a high of 13 percent in 1935.

The relative importance of egg production doubled from 1924 to 1929 when the proportion of cash farm income from eggs increased from 4 to 9 percent. Since 1929 it has fluctuated without apparent trend. The percentage of cash income from eggs was high in years when egg prices were high relative to the other agricultural products and low …

Bulletin No. 384 - Virus And Viruslike Diseases Of Stone Fruits In Utah: A Handbook For Their Identification And Control, B. L. Richards, L. C. Cochran

UAES Bulletins

Intensive research over the last 20 years has shown that many of the previously unexplained and seemingly mysterious disorders of stone fruit trees in Utah are infectious diseases caused by viruses. Others were shown to be the result of noninfectious genetic abnormalities or of adverse chemical and physical factors in the environment of the plant. The purpose of this handbook is to help orchardists and others recognize these diseases and disorders and understand better their etiology or cause. The handbook will also bring together basic information which will aid in their control.

Bulletin No. 379 - Biology And Control Of The Peach Twig Borer (Anarsia Lineatella Zeller) In Utah, Charles J. Sorenson, Farrell H. Gunnell

UAES Bulletins

The peach twig borer, Anarsia lineatella Zeller, sometimes called the peach worm, annually damages peach, apricot, nectarine, prune, and plum orchards in Utah. Many buds and twig terminals are destroyed each spring by the overwintered generation of partially grown larvae. These emerge from their winter quarters almost as soon as host trees begin their spring growth. From the time the fruit becomes about half grown until it is harvested, later generations of twig-borer larvae feed on it causing irregular, gummy cavities which make it unfit for market.

In order to work out a control program for any insect, its life …

Bulletin No. 373 - Biennial Report Of The Utah Agricultural Experiment Station, 1952-1954

UAES Bulletins

Our way of life is based on the ability of our agriculture to produce abundantly, efficiently, and at a low cost; and the position of agriculture today is largely a result of the research efforts of the state agricultural experiment stations and the United States Department of Agriculture. In the 66 years since the establishment of the Utah Agricultural Experiment Station, its scientists have found solutions to many of the problems peculiar to its location, topography, and climate. It is logical to rely on these same research forces to solve the problems of the future.

During the past biennium a …

Bulletin No. 370 - The Superb Plant Bug, Adelphocoris Superbus (Uhler): Its Life History And Its Relation To Seed Development In Alfalfa, Charles J. Sorenson, Lowell Cutler

UAES Bulletins

Infestations of the superb plant bug, Adelphocoris superbus (Uhler), in Utah alfalfa fields first came to the attention of entomologists of the Utah Agricultural Experiment Station during their investigations of the seed chalcid and lygus bug problems of alfalfa seed production in the Uinta Basin from 1926 to 1934. Because of its occurrence in considerable numbers, particularly in first crop alfalfa fields with thin stands, the superb plant bug was suspected of interfering with seed development. Consequently an investigation of the activities of this insect was begun in the summer of 1932 and continued through that of 1933.

Objectives sought …

Bulletin No. 363 - Butyl Fabrics As Canal Lining Materials, C. W. Lauritzen, W. H. Peterson

UAES Bulletins

The most important prerequisite of linings for controlling seepage losses from irrigation canals is their watertightness. In addition to being watertight, a lining must be relatively durable if it is to be economical. Rigid materials provide satisfactory linings for canals with well-drained and stable subgrades. Under other conditions, where expansive soils are encountered and ground water is a problem, a rigid lining such as concrete is not durable. Considering the many factors that govern the utility and durability of linings, the ideal lining would consist of a material with some flexibility, a material resistant to erosion and mechanical damage, and …

Anther Development In A Male Sterile Line Of Corn, Richard J. Vogl

Bachelors’ Theses

Production of viable pollen through growth and differentiation of the anther appears to depend on the interaction of the tapetum and sporogenous tissue. Very little is known about the nature of this interaction. One way to approach this problem is to study the development of the anther in cases where no viable pollen grains are produced. Highly inbred lines of male sterile corn which are completely pollen sterile have been obtained and are available for study.

Bulletin No. 358 - The Rainbow Trout In Relation To The Other Fish In Fish Lake, William F. Sigler

UAES Bulletins

The coast rainbow Salmo gairdnerii irideus Gibbons is not indigenous to Utah. Its original range is Pacific North America from Alaska to Mexico. The coast rainbow was first introduced into Utah in 1883 from McCloud River, California.

The rainbow is used more extensively for artificial propagation than any other trout in North America, both for sport fishing and as a commercial food fish. Its natural habitat is big lakes and rivers; it can adapt itself to relatively small ponds, but it does not reproduce in these ponds.

Limnological and fishery investigations on Fish Lake were initiated in 1922 and have …

Bulletin No. 357 - Biennial Report, 1950-1952, R. H. Walker, D. A. Broadbent

UAES Bulletins

For sixty-four years the Utah Agricultural Experiment Station has been studying the problems of the farmer to make life on the farm more profitable and more enjoyable and in turn to improve the economy of the entire state. From the laboratories and from the experimental farms have come research results that have and will continue to mean dollars and cents to the farmer and increased prosperity to the state. Here are a few brief statements of some of the results of the work during the past two years.

Bulletin No. 347 - The Life History And Management Of The Mountain Whitefish Prosopium Williamsoni (Girard) In Logan River Utah, William F. Sigler

UAES Bulletins

In 1948 a comprehensive fishery investigation on Logan River was initiated by the Department of Wildlife Management, Utah State Agricultural College, and the Utah Cooperative Wildlife Research Unit. Three masters' theses have been completed on life histories and populations to date (Thoreson, 1949; Fleener, 1950; Pechacek, 1950). One phase of this investigation is a study of the mountain whitefish Prosopium williamsoni (Girard).

Microorganisms And Soil Structure, T. M. Mccalla

Department of Agronomy and Horticulture: Faculty Publications

SUMMARY

Laboratory tests were made to determine the effectiveness of different compounds and microbial groups in increasing the stability of Peorian loess lumps against the action of falling water drops. The influence of these on percolation tests in the laboratory was also determined.

Many organic substances-dextrose, sucrose, starch, peptone, cullulose, and gum arabic-did not themselves contribute directly to soil-structure stability, though these substances do furnish energy material for soil microorganisms, which can convert them readily into either microbial tissue or decomposition products that increase soil-structure stability. Lignin, proteins, oils, fats, waxes, resin, and paraffin increased the stability of lumps of …

Application Of Schuepp's Method To Form Analysis Of The Shoot Apex In Maize, Otto L. Stein, Ernst C. Abbe

Journal of the Minnesota Academy of Science

No abstract provided.

Bulletin No. 336 - Utah Agricultural Experiment Station Biennial Report, 1946-1948, R. H. Walker

UAES Bulletins

During the past biennium there has been a general expansion in the research program of the Agricultural Experiment Station. This was made possible through increased state legislative appropriation and through federal funds made available by the Agricultural Research and Marketing Act which passed Congress in August 1946, although funds were not available until August 1947. Grants-in-aid by state and private agencies have also made other research possible.

Bulletin No. 327 - Utah Agricultural Experiment Station Biennial Report, 1944-1946, R. H. Walker

UAES Bulletins

During the past biennium there has been a general expansion in the research program of the Utah Agricultural Experiment Station. Although some of the investigations were curtailed by lack of personnel and equipment and the pressure of wartime assignments, many of the staff were able to devote more time to research because of a lessening of the teaching load at the College. The emergency caused a re-examination of the research program, old projects, no longer urgent were weeded out, others were revised to meet the needs of the changing times, and many new projects were initiated to extend the research …

Farm Fishponds, Verne E. Davison

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

An important part of soil and moisture conservation is making the best use of every acre on the farm. Where a suitable site for a farm pond exists, no better use can be made of such land than to develop it for the production of fish for the farm family. The recreation the pond affords adds much to the pleasure of rural life.

Thousands of farms have good pond sites. Properly developed and managed ponds may provide both food and pleasure to more than a million farm people.

This bulletin tells how to have good ponds. It explains how to …

Bulletin No. 315 - Biennial Report, 1942-1944

UAES Bulletins

The war years have made new demands on Station personnel and facilities. With fewer staff members and less adequate equipment the Station has not only carried on the regular project work, but the research program has been expanded, and numerous activities resulting from the emergency have been assumed.

The Station has taken a leading place in the victory food production program. Each year it has assumed the lead in a study of the wartime agricultural production capacity of the state and desirable crop and livestock adjustments studying all the agricultural assets and the ability to produce various crops.

As a …

Bulletin No. 310 - The Influence Of Cropping On The Nitrogen, Phosphorus And Organic Matter Of The Soil Under Irrigation Farming, J. E. Greaves, C. T. Hirst

UAES Bulletins

Most soils contain sufficient nutrients for normal plant growth, with the exception of nitrogen, phosphorus and potassium. These elements are used by plants in the largest quantities and the amounts of these in the soil govern its productivity. Soil organic matter is of prime importance for it is the matrix which holds the nitrogen and modifies the structure, temperature, and water-holding capacity of the soil. The organic matter is the very life of the soil, for it is in and on it that bacteria work and by so doing determine the kind and speed of reactions which occur. It is …

Bulletin No. 305 - The Composition Of Sumer Range Plants In Utah, L. A. Stoddart, J. E. Greaves

UAES Bulletins

In Utah, a vast industry of livestock grazing, which is the backbone of the state's agriculture, has arisen during the past 75 years. Range land furnishes between 6 and 7 million animal unit months of forage to some 2 1/2 million sheep and 275 thousand range cattle. Income from meat, wool, and range livestock sales in Utah is about $15,801,500 annually, of which $11,700,000 is calculated to be obtained from range lands exclusive of cultivated pastures.

These range lands can be used economically in no other way than by grazing livestock and, because of heavy winter snows and protracted dry …

Bulletin No. 302 - Nutritional Inadequacy Of Beet Molasses Rations For Swine, Russel A. Rasmussen, Harry H. Smith, Ralph W. Phillips, Ton J. Cunha

UAES Bulletins

The feeding of large amounts of beet molasses to young hogs causes a condition that is characterized by a wobbly gait, and that is frequently fatal. Hog raisers have apparently recognized this condition for a number of years, since a number of farmers have reported it in their animals. Some farmers have also reported breeding failures and abortions when beet molasses was fed to brood sows. Consequently, beet molasses has not been considered a good hog feed by Utah raisers.

Beet molasses is a relatively cheap source of carbohydrates and could be used advantageously in pork production if the cause …

A Study Of Origins And Ecological Features Of Hardy, Cultivated, Herbaceous Plants Of Milwaukee, Wisconsin, Dorothy Elaine Witheck

Bachelors’ Theses

Gardeners have always been interested in herbaceous plants, chiefly because of their beauty and usefulness. As a result of the great popularity, a large number of attractive varieties have been produced through centuries of' cultivation, selection and breeding. Very early agricultural and medical demands stimulated an interest in the plants, and as early as 372-287 B.C. Theophrastus, a pupil of Aristotle, described about 460 cultivated plants and classified them as herbs, undershrubs, shrubs and trees. Much of the work accomplished by the ancient Greeks was lost and it was not until the sixteenth century that renewed enthusiasm for the study …