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Articles 391 - 420 of 488
Full-Text Articles in Animal Sciences
The Asexual And Sexual Stages Of Eimeria Auburnensis In Calves, Bill Chobotar
The Asexual And Sexual Stages Of Eimeria Auburnensis In Calves, Bill Chobotar
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
In a study of the life cycle of Eimeria auburnensis, 51 of 57 Holstein-Friesian calves were used to study endogenous stages, and the remainder to investigate the prepatent and patent periods. In vitro excysted sporozoites of E. auburnensis were introduced into intestinal fistulas in 8 calves and into the intestine via laparotomy in 2 others. One or more of the 51 calves were killed at daily intervals beginning on the second day and continuing until the 19th day after inoculation. The tissues from calves were prepared by routine histological techniques for nicroscopic examination. First-generation asexual endogenous stages were located …
The Value Of A Trout Stream Fishery, Archie Allen Dyer
The Value Of A Trout Stream Fishery, Archie Allen Dyer
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The data analysis indicated that travel distance, user age, and user income level are important determinants of use of trout streams.
These variables were incorporated into regression analysis to develop a use-prediction model.
This use-prediction model was used to determine predicted use levels of sample streams. The predicted use levels combined with travel costs and expenditures on new fishing equipment were used to derive a statistical estimate of the demand schedules for the sample streams.
These statistical demand curves were subjected to consumer surplus procedures to determine the values of the sample streams.
Comparisons Of Phytoseiid Predator Populations In Sprayed And Unsprayed Apple Orchards In Cache Valley, Utah, Yeboa A. Dodoo
Comparisons Of Phytoseiid Predator Populations In Sprayed And Unsprayed Apple Orchards In Cache Valley, Utah, Yeboa A. Dodoo
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A comparative study of phytoseiid populations was made of two well-cultivated and regularly sprayed apple orchards with two unsprayed orchards in Cache Valley, northern Utah.
Two phytoseiid species, Typhlodromus mcgregori Chant and T. occidentalis Nesbitt were observed on the apple leaves, under the bark, and occasionally in the litter and soil. Amblyseius cucumeris (Oudemans) occurred in the soil and litter and occasionally under bark. T. mcgregori was dominant in the unsprayed orchards, and T. occidentalis in the sprayed.
Of the phytophagous mites, which served as food for the phytoseiids, the two-spotted mite, Tetranychus urticae Koch was dominant. Other phytophagous mites …
A Description Of The Planarian Phagocata Crenophila, New Species, From Utah, Jerry H. Carpenter
A Description Of The Planarian Phagocata Crenophila, New Species, From Utah, Jerry H. Carpenter
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A new species of planaria in the genus Phagocata was found in several springs and spring-fed streams in Logan Canyon, Cache County, Utah. This species was named Phagocata crenophila because it greatly prefers to live in springs and it seems to be adapted behaviorally to this type of habitat. Serial sections and whole mounts were made by standard methods in order to study the anatomical features which are necessary for identification of planarians. The distinguishing features of this species are the following: testes ventral and extending from near the brain to near the posterior end, ejaculatory duct opening ventrally from …
Local Distribution In A Population Of Uinta Ground Squirrels, Robert Edgar Walker
Local Distribution In A Population Of Uinta Ground Squirrels, Robert Edgar Walker
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
In an attempt to describe, explain, and show the demographic significance of annual variations in the nesting distribution of Uinta ground squirrels, a study was conducted during the summers of 1964 through 1967 in northern Utah. Procedures included both trapping and direct observation.
It was found that females tended to nest in open, previously inhabited, grassy areas. Males resided throughout a variety of habitats.
This typical nesting distribution was established initially in the summer by juveniles shortly after they first appeared aboveground. The extent to which the distribution was maintained the following spring depended largely upon the number of female …
Effects Of Temperature On In Vitro Excystation Of Various Eimeria Species, Larry E. Hibbert
Effects Of Temperature On In Vitro Excystation Of Various Eimeria Species, Larry E. Hibbert
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Cleaned oocysts of Eimeria bovis, E. ellipsoidalis, E. auburnensis, and E. zurnii of cattle, E. ahsata and E. ninakohlyakimovae of sheep, E. bilamellata and E. callospermophili of the ground squirrel, and E. tenella of chickens were pretreated with 50 percent carbon dioxide/50 percent air at temperatures ranging from 29 to 45 C with 2 degree intervals for 4, 6, 8, 10, and 30 hours and treated with bile and trypsin.
The optimum temperature in species of ruminant coccidia was 39 to 41 C. In E. bovis, excystation occurred from 29 to 43 C. At 43 C and above, …
The Influence Of Hot Brine On The Calcium Content, Score, And Physical Properties Of Low-Fat, Cheddar-Like Cheese, Robert V. Ogden
The Influence Of Hot Brine On The Calcium Content, Score, And Physical Properties Of Low-Fat, Cheddar-Like Cheese, Robert V. Ogden
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Two factors that are important in the production of the typical body and texture of cheddar cheese are acid development and milk fat content. When either of these is absent or present in less-than-normal amounts, the resulting cheese shows marked defects of curdiness and firmness.
When acid development in a vat of cheese is arrested, it is referred to as a "dead" vat. The cheese from this vat may be salvaged by use of the hot brine method of treatment. Hot brine treated cheese, although lacking the desired acid development, is a reasonably acceptable product, having the desired characteristics of …
Heat Denaturation Of Serum Proteins In Skimmilk And Whey As Measured By The Harland-Ashworth Test, Lynn Verl Ogden
Heat Denaturation Of Serum Proteins In Skimmilk And Whey As Measured By The Harland-Ashworth Test, Lynn Verl Ogden
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Milk serum proteins have been shown by other workers to be partially protected from heat denaturation by the presence of milk solids (8, 15, 16) and whole caseinate (14). This study revealed that some serum proteins (B-lactoglobulin), as shown by the Harland-Ashworth test (14, 17), were more readily denatured in skimmilk than in rennet whey. A comparison of the heat denaturation rate of serum proteins in whey as opposed to those in whey containing 2.5 percent isoelectric casein was also studied. A striking protection of serum proteins seemed apparent in the presence of isoelectric casein. However, it was learned that …
Feeding Ecology And Territorial Behavior Of The Yellow Warbler, Merrill J. Frydendall
Feeding Ecology And Territorial Behavior Of The Yellow Warbler, Merrill J. Frydendall
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A controversy dating from the appearance of Altum's book, Der Vogel und sein Leben, 1868 (Mayr, 1935) is that of the biological function or functions of the territorial behavior in birds. However, attention was not focused upon this problem until the advent of Howard's book, Territory in Bird Life, published in 1920. In a general review of the problem Hinde (1956) discussed several functions of the territory and presented evidence both for and against their importance. The more important of these presumed functions are: (1) limitation of population density; (2) facilitation of pair formation and maintenance of the …
The Incidence And Life Cycle Of Eimeria Utahensis Sp. N. From Kangaroo Rats Of Northwestern Utah, John V. Ernst
The Incidence And Life Cycle Of Eimeria Utahensis Sp. N. From Kangaroo Rats Of Northwestern Utah, John V. Ernst
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A total of 176 kangaroo rats (151 Dipodomys ordii and 25 D. microps) were captured in northwestern Utah and examined for coccidia. Of these 176 rats, four D. ordii (2.6%) and four D. microps (16.0%) were infected with Eimeria utahensis, a new species of coccidia. Little seasonal difference was found in the infection rate of either species. The characteristics of the sporulated oocysts of this species were described. A sporocyst plug was reported for the first time in an eimerian oocyst.
Artificially excysted sporozoites were studied by various methods. Thirty living sporozoites averaged 22.5 𝜇 in length by …
An Examination Of A Putative System For The In Vitro Synthesis Of Drosophila Tryptophan Pyrrolase, John P. Phillips
An Examination Of A Putative System For The In Vitro Synthesis Of Drosophila Tryptophan Pyrrolase, John P. Phillips
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A system, reported by Morrison (1964), for the in vitro synthesis of Drosophila tryptophan pyrrolase has been critically studied. This putative system is based on the addition of a Drosophila "RNA" extract to a Drosophila cell-free protein synthesizing system; the synthesized enzyme is then allowed to catalyze a specific reaction, the product of which is measured by direct adsorption.
The results of this study present a three-fold argument against the interpretation of synthesis of tryptophan pyrrolase in the Morrison in vitro system: (1) RNA from a null-allele, v36f, stimulated the same tryptophan pyrrolase "activity" in the in vitro …
Eutrophication Trends Of Bear Lake, Idaho-Utah And Their Effect On The Distribution And Biological Productivity Of Zooplankton, David Nyquist
Eutrophication Trends Of Bear Lake, Idaho-Utah And Their Effect On The Distribution And Biological Productivity Of Zooplankton, David Nyquist
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Zooplankton of the littoral and limnetic zones of Bear Lake, Idaho-Utah, were collected over a 17-month period. Twenty-three species of zooplankton were recorded, as well as nine other species represented by both flora and fauna. At the time of sampling 17 physical and chemical parameters were also measured. Methods of analysis for the plankton and the environment are described and discussed.
The objectives of this project were fourfold:
- To establish a record of the current zooplankton population before changes due to the increase of organic nutrients occur.
- To compile a qualitative and quantitative standard against which future populations can be …
Life Cycles Of Three Species Of Eimeria From The Uinta Ground Squirrel, Spermophilus Armatus, Kenneth S. Todd Jr.
Life Cycles Of Three Species Of Eimeria From The Uinta Ground Squirrel, Spermophilus Armatus, Kenneth S. Todd Jr.
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A study of the coccidia of the Uinta ground squirrel, Spermophilus (Citellus) armatus, was undertaken to determine the incidence of coccidia in a population of these ground squirrels, the life cycle and pathogenicity of the coccidia, and the host specificity of certain of the species of coccidia found in this and five other species of ground squirrels (S. richardsoni, S. variegatus, S. lateralis, S. columbianus, and S. beecheyi).
Uinta ground squirrels were live trapped and their feces examined to determine the incidence of coccidian infection. Specimens of S. armatus were maintained in the laboratory and given a pure inoculum of …
The Use Of Amprolium In Controlling Coccidiosis In Lambs, Joseph E. Kuta
The Use Of Amprolium In Controlling Coccidiosis In Lambs, Joseph E. Kuta
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Young lambs are subject to severe infections with coccidiosis, which cause weight loss, morbidity, woolbreaking, and death (Christensen, 1940b; Shumard, 1957; Lotze, 1959; Smith et al., 1960). Dunlap et al. (1949) have shown that the adult sheep are reservoir hosts and are a constant source of infection to lambs. Outbreaks of coccidial infections, especially under feedlot conditions, are frequent (Newsom and Cross, 1931; Piras, 1934; Deem and Thorp, 1940; Mahrt and Sherrick, 1965).
Gonadotropic Hormone Activity In Blood And Placental Tissue Of The Bovine Early In Gestation, John E. Lunnen
Gonadotropic Hormone Activity In Blood And Placental Tissue Of The Bovine Early In Gestation, John E. Lunnen
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Certain mammalian species have been shown to secrete extra-pituitary gonadotropins. In humans the chorionic cells of the placenta secrete a gonadotropin and in pregnant mares such a hormone is secreted by the endometrial cups. Gonadotropins of placental origin have also been observed in the rat.
Immunity To Ostertagiasis In Calves, Leo F. Lejambre
Immunity To Ostertagiasis In Calves, Leo F. Lejambre
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Parasites are responsible for heavy economic loss to the livestock industry. The losses in cattle due to parasitism can only be roughly estimated, since many cattle do not die or become visibly sick. However, there are more subtle losses such as reduced growth rate, and decreased meat and milk production (Levine, 1961). In 1954 the U. S. Department of Agriculture published an estimate of the losses in agriculture over the 10 year period, 1942-1951. At that time, the best judgement of specialists in the Department of Agriculture placed the annual loss to parasitism in cattle at $19,026,000 of which $8,989,000 …
A Cytological Study Of Certain Life Cycle Stage Of Eimeria Bovis, John V. Ernst
A Cytological Study Of Certain Life Cycle Stage Of Eimeria Bovis, John V. Ernst
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Although much research has been done on the bovine coccidia little has been reported on the cytological nature of the different stages. Few descriptions of cytoplasmic structures occur in the literature. Because of the impermeability of the oocyst wall a definitive study of the nucleus in the unsporulated oocyst has not been made, nor have the nuclear changes during the two successive divisions which occur during the process of sporulation been described.
The Initiation Of Infection By Dna From Bacteriophage Lambda, Gerald D. Elseth
The Initiation Of Infection By Dna From Bacteriophage Lambda, Gerald D. Elseth
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Deoxyribonucleic acid isolated from bacteriophage λ can infect Escherichia coli K12 in the presence of adsorbed helper phage (Kaiser and Hogness, 1960; Kaiser, 1962). The manner in which λ DNA enters the cell and the possible role of helper phage in the penetration process is still not clear. Kinetic studies conducted in this laboratory during the initial stages of infection by λ DNA demonstrate a requirement for helper function during the penetration of an infectious molecule. Further investigation into this problem is needed and was the major objective of this study.
Studies On Amino Acid Balance In Three Fish Meals, Krachang Wisutharom
Studies On Amino Acid Balance In Three Fish Meals, Krachang Wisutharom
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
High levels of fish mean cannot be used in chick diets in the United States because of the relatively high cost as compared to soybean meal. In certain areas or countries where large amounts of fish meal are produced, it may be economically feasible to use fish meal as the major protein supplement in the poultry rations.
Feed consumed by poultry must provide most of the materials the birds need for growth or to produce eggs. Those who formulate feed must select ingredients and combine them in proportions which will allow the bird to grow or produce eggs at the …
The Relative Accuracy Of Estimating The Production Of Dairy Cows As Affected By Length Of Testing Interval And Method Of Estimating Production, Ross M. Young
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Production records for dairy cows were first based on the yield of butter for a seven day period any time during the lactation. Later, 365- day records based on production for one day in each calendar month came into general use. The records preferred at present are 305- day records based on monthly test day production, but calculated using the centering date method. The centering date estimate is based on milk and butterfat production from two consecutive milkings per month. The sampling day is centered as nearly as possible in the test month period which need not coincide with the …
Canada Goose Production And Population Stability, Ogden Bay Waterfowl Management Area, Utah, Norman H. Dey
Canada Goose Production And Population Stability, Ogden Bay Waterfowl Management Area, Utah, Norman H. Dey
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Since the development of Ogden Bay Waterfowl Management Area in 1937, the Canada goose (Branta canadesis moffitti) population increased to a peak in 1949 and then declined slightly. Nelson (1954) noted that the decrease in population was probably due to either a change in habitat or increased hunting pressure. In recent years, direct band returns have indicated a high mortality rate in the population. This project was initiated to determine the relative stability of the Canada goose population and to measure, as closely as possible, the effect of a high mortality rate upon the nesting population.
Effects Of Beaver On Stream Flow And Water Quality, James W. Bates
Effects Of Beaver On Stream Flow And Water Quality, James W. Bates
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Water, one of the major resources of the western lands, controls the economy and expansion of the communities. Industry, agriculture, timber, livestock, game and home water needs are all dependent upon a steady and continued flow of water from wells, springs, and rivers. Water is derived from one source, precipitation, which occurs in the form of rain and snow. Watersheds which are properly managed accumulate a substantial snow pack during the winter which is the life-giving source of water for our springs.
The Utah Water and Power Report (1948) indicates the annual precipitation over the entire state of Utah averaged …
Lactation Efficiency Of Holstein Cows As Related To Rate And Efficiency Of Growth, Charles H. Mickelsen
Lactation Efficiency Of Holstein Cows As Related To Rate And Efficiency Of Growth, Charles H. Mickelsen
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The relationship of quantity and quality of feed to milk production has been studied for many years. Feeding standards have been developed to systematize feeding of dairy cows according to their requirements. Recently, interest in efficiency of cows in converting feed nutrients into milk has increased.
Ecological Factors Influencing Plant Distribution In The Shadscale Zone Of Southeastern Utah, Kamal M. Ibrahim
Ecological Factors Influencing Plant Distribution In The Shadscale Zone Of Southeastern Utah, Kamal M. Ibrahim
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The intimate relationship between vegetation and soil has long been a subject of interest. Ecologists, soil surveyors, and ranchers have recognized that vegetation differences are often accompanied by variation in soil types.
A Study Of The Use Of The Hydrogen Peroxide-Catalase Treatment Of Milk In The Manufacture Of A Reduced Fat, Cheddar-Like Cheese, Lamar John Johnson
A Study Of The Use Of The Hydrogen Peroxide-Catalase Treatment Of Milk In The Manufacture Of A Reduced Fat, Cheddar-Like Cheese, Lamar John Johnson
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Nutritionists, the medical profession, and the public in general have become increasingly interested in low fat food products. Cheddar cheese, as it is now made, has a high caloric value and therefore may be discriminated against in some diets. The production of a reduced fat cheddar-like cheese would be of importance to the cheese industry by providing a reduced fat, high protein product.
The chemical nature of the casein furnishes the foundation for the body and texture in cheese. The body and texture of typical cheddar cheese is influenced principally by its fat and moisture content.
The use of hydrogen …
Group Grain Feeding Versus Individual Grain Feeding Of Lactating Dairy Cows, Earl Max Sudweeks
Group Grain Feeding Versus Individual Grain Feeding Of Lactating Dairy Cows, Earl Max Sudweeks
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Grain feeding is an important part of a dairy feeding program. Grain supplies energy in a concentrated form and when fed as a supplement to forage permits cows to maintain high levels of production. Also, if the forage is of low quality, additional protein and other nutrients can be supplied with the grain in a concentrate mix. By feeding a balanced concentrate mix, according to individual production, each cow receives the necessary nutrients for production. Dairy cows are usually fed grain individually.
Factors Affecting The Waterfowl Hunter Utilization And The Waterfowl Kill At The Bear River Migratory Bird Refuge, 1960-61, Stephen V. Goddard
Factors Affecting The Waterfowl Hunter Utilization And The Waterfowl Kill At The Bear River Migratory Bird Refuge, 1960-61, Stephen V. Goddard
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
In 1960 there were 1,955, 000 waterfowl hunters in the United States. These hunters spent $89,431, 000 (an average of $45.74 per individual) and 15,158, 000 hunter days in the field. The hunting population will increase 35 percent by 1975 (Anonymous, 1960).
The large increase in hunters will bring a proportional increase in the demand for places to hunt. Many states face the problem of providing enough public hunting for such an army of sportsmen. Studies by Kozlik (1958) in California, Gordinier (1957) and Friley (1959) in Michigan, and Bednarik (1957, 1961) in Ohio point out some of the problems …
Influence Of Age On Milk Production Of Holstein Cows In Utah, Marvin R. Green
Influence Of Age On Milk Production Of Holstein Cows In Utah, Marvin R. Green
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Production of dairy cows is influenced by many factors, among which are: genetics, nutrition, management, disease and age. Most of these factors can be modified to maintain a high level of production. Age, however, is beyond the influence of mankind; therefore, it is important to understand the effect of age on milk and butter-fat production.
A Study Of The Effects Of Acidity On Shelf Life And Type Of Spoilage In Market Milk, Jagannath M. Kudale
A Study Of The Effects Of Acidity On Shelf Life And Type Of Spoilage In Market Milk, Jagannath M. Kudale
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The addition of the Streptococcus lactis culture in the pasteurized milk was studied, in an attempt to find the effects of the culture in prolonging shelf life of the milk. Various concentrations of the culture were tried to find the optimum concentration that would give favorable effect on keeping quality of the milk. It was found that the addition of Streptococcus lactis culture at the rate of 0.0001 percent has shown promising effects in prolonging shelf life of the milk at the storage temperature of 40 F.
In addition to the above study, effects of added acid in the pasteurized …
Deviations In Serum Proteins Associated With Eimeria Bovis Infections In Calves And Some Related Immune Reactions, Paul R. Fitzgerald
Deviations In Serum Proteins Associated With Eimeria Bovis Infections In Calves And Some Related Immune Reactions, Paul R. Fitzgerald
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Bovine coccidiosis is a serious threat to the economy of the cattle industry in the United States. In 1954 the United States Department of Agriculture reported that over $10,000,000 was lost annually as a result of mortality and morbidity in cattle due to this parasite (1). These losses alone amounted to more than one fourth of the total loss in cattle due to parasitism.