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Articles 2881 - 2910 of 3160
Full-Text Articles in Life Sciences
Dye Marking Of Antibiotics Used In Treatment Of Mastitis In Dry And Lactating Cows, Richard A. Ellefson
Dye Marking Of Antibiotics Used In Treatment Of Mastitis In Dry And Lactating Cows, Richard A. Ellefson
Electronic Theses and Dissertations
Mastitis is the one major disease affecting dairy cows; considerable direct and indirect economic losses can be attributed to mastitis (6). Treatment of mastitis with antibiotic preparations will alleviate most disease symptoms. Problems may arise when cows treated with antibiotics have their milk used for commercial milk processes before antibiotics are clear. They are: 1) some people are allergic to penicillin, and 2) cultured dairy products may not grow because of inhibition. The Food, Drug, and Cosmetic Act established that milk and milk products containing antibiotics are considered adulterated. Due to recent innovations in antibiotics testing The National Conference on …
Whey-Caseinate Blends And Lactose Hydrolysis In Yogurt Manufacture, Catherine A. Whalen
Whey-Caseinate Blends And Lactose Hydrolysis In Yogurt Manufacture, Catherine A. Whalen
Electronic Theses and Dissertations
Yogurt is a highly nutritious cultured dairy product which has been consumed for centuries, particularly in Eastern Europe. Although per capita consumption in the United. States is still far below that of most European countries; yogurt sales in the U.S.A. have increased phenomenally during the past three decades. Yogurt sales in the U.S.A. totaled 7.7 million kg in 1955; 31.8 million kg in 1966; and approximately 227 million kg by 1976 (41). Per capita sales increased 211% from 1970 to 1980 (45). Yogurt is generally manufactured from milk or lowfat milk which has been fortified with extra milk solids. Nonfat …
Feeding Value Of High Starch And High Fat Rations For Dairy Calves, G. Duff Stewart
Feeding Value Of High Starch And High Fat Rations For Dairy Calves, G. Duff Stewart
Electronic Theses and Dissertations
Sixty-four Holstein calves were used in a 3 x 2 factorial experiment of 12 wk to evaluate growth performance when fed control, high starch, and high fat pelleted diets separately or with a supplemental concentrate mix offered the first 6 wk. High starch and high fat diets were formulated to .contain more digestible energy than the control diet. Calves received milk the first 5 wk, plus one of the above rations ad libitum wk 1 thru 12. The control diet contained corn, oats, and soybean meal; the high starch diet contained corn and soybean meal; while the high fat diet …
Use Of Dry Whey And Lactose Hydrolysis In Yogurt Bases, Nagendra P. Shah
Use Of Dry Whey And Lactose Hydrolysis In Yogurt Bases, Nagendra P. Shah
Electronic Theses and Dissertations
Yogurt is one of the oldest and most traditional fermented dairy products. Since early times it has been an important food item of the people in the Middle East. Except for its refreshing taste and wholesomeness as a food, no special virtues were claimed for it until early in the 20th century when the bacteriologist, Elie Metchnikoff, who shared a Nobel Prize in 1908, concluded from his studies on the effect of lactic acid bacteria of the digestive tract, that yogurt arrests putrefaction in the intestinal tract and thus might be beneficial to health (55). Attempts to popularize yogurt in …
Effects Of Site Preparation On Survival And Growth Of Planted Loblolly Pine, John Gorham
Effects Of Site Preparation On Survival And Growth Of Planted Loblolly Pine, John Gorham
Electronic Theses and Dissertations
Effects of site preparation on survival and growth of planted loblolly pine (Pinus taeda L.) on a loblolly-shortleaf pine-hardwood forest site in East Texas are examined by determining the survival and growth of planted loblolly pine, soil chemical characteristics, and density and height of competing (non-pine) woody stems. Three replications of four site preparation treatments (control, burn, chop, KG blade) resulted in the KG bladed plots having the highest survival, height, and diameter, but the lowest nutrient levels while, also, most effectively controlling competing vegetation. This tends to indicate that the advantages in the initial survival and growth on the …
Hydrolyzed-Lactose Whey And Nonfat Dry Milk In Ice Cream, Mohammed Serajul Islam
Hydrolyzed-Lactose Whey And Nonfat Dry Milk In Ice Cream, Mohammed Serajul Islam
Electronic Theses and Dissertations
Sweet dry whey was used to replace 25% and 50% of nonfat dry milk solids in ice cream mix. Forty-five batches experimental and control lots of vanilla ice cream were manufactured. A commercial lactase was used to hydrolyze lactose to over 90% conversion and the lactase was inactivated after hydrolysis. The extent of lactose hydrolysis in the mix was adjusted to 50% or 75% by blending non-hydrolyzed nonfat dry milk and whey solids with hydrolyzed preparations. Extra sweetness of the conversion products permitted reduction of sucrose by 6.25% and 12.5%, respectively, in the 50% and 75% hydrolyzed lactose ice cream …
Lactase Activity In Steers Fed Large Amounts Of Dried Whey, Kenneth J. King
Lactase Activity In Steers Fed Large Amounts Of Dried Whey, Kenneth J. King
Electronic Theses and Dissertations
Large amounts of dried whole whey (86% of concentrate mix, 60% of total dry matter intake) were fed to four Holstein steers in place of corn and soybean meal in the control diet to evaluate the extent and site of lactose digestion in the ruminant's digestive tract. Diets consisted of 70% of the dry matter as concentrate mix and 30% as corn silage fed ad libitum as a total mixed ration. Weight gains and dry matter intakes were similar for steers fed dried whole whey or control diets. Samples of rumen contents from steers fed dried whole whey contained more …
Studies On Beneficial And Adverse Effects Of Dietary Buffers For Lambs, Jong Kyu Ha
Studies On Beneficial And Adverse Effects Of Dietary Buffers For Lambs, Jong Kyu Ha
Electronic Theses and Dissertations
Experiments using lambs were conducted to study the effects of buffers or roughages against acidosis occurring during rapid dietary changes. Experiments using rats were conducted to investigate vitamin A and thiamin stability and/or utilization as influenced by bentonite. Incubating rumen fluid in vitro at a pH lower than 6 reduced volatile fatty acid (VFA) production and increased lactate accumulation. Limestone or bentonite at levels of 2% in 92% concentrate diets had little effect on feed intake or rumen and blood parameters during a 7-day treatment period using rumen-canulated sheep. However, 2% NaHCO3 increased rumen pH and feed intake on …
Dye Marking Of Antibiotics Used In Treatment Of Mastitis, Nancy Fairbank Novak
Dye Marking Of Antibiotics Used In Treatment Of Mastitis, Nancy Fairbank Novak
Electronic Theses and Dissertations
The National Mastitis Council, Inc. defines mastitis as the infection of udder tissues (74). Mastitis is the most costly disease affecting dairy cows; many people do not realize the considerable losses due to mastitis (6). A reasonable estimate of the prevalence of mastitis is 50% of cows infected at any time (62); cows in the average herd contract clinical mastitis 1.5 times per year (74). The minimum antibiotic treatments per case of mastitis is two; with approximately 11 million dairy cows in the United States, the annual minimum number of antibiotic treatments is 33 million. In South Dakota, with nearly …
The Effects Of Rancid Milk On Cheddar Cheese, Shane Thomas Mcdonald
The Effects Of Rancid Milk On Cheddar Cheese, Shane Thomas Mcdonald
Electronic Theses and Dissertations
One of the most serious defects .of fluid milk is hydrolytic rancidity. Although not a new problem, recent practices in the dairy industry have increased its incidence. On the farm, the use of pipeline milking and transferring systems, in conjunction with bulk cooling and storage, involves excessive agitation and foaming of the raw milk. Both agitation and foaming enhance the development of rancidity. Additional agitation occurs when milk is pumped into storage silos, and pumped about the plant f or processing. Dairy processing facilities are becoming more centralized. Hence, raw milk must be transported longer distances to the dairy plants. …
Preservative Effects Of Covering And Propionic Acid On Alfalfa Haylage In Bunker Silos, Thomas Jonathan Oelberg
Preservative Effects Of Covering And Propionic Acid On Alfalfa Haylage In Bunker Silos, Thomas Jonathan Oelberg
Electronic Theses and Dissertations
The preservation efficiency of covering alfalfa haylage with black plastic (polyethylene) and/or treating haylage with propionic acid was studied in two trials. Experiment 1 was designed to evaluate the influence of both covering and treatment with propionic acid on haylage chemical composition and heifer growth. In experiment 1, prop ionic acid was administered to the haylage at the chopper at 0.02% of the fresh forage weight. Chemical composition and ensiling temperature of the haylage were monitored and animal growth was measured with 16 Holstein heifers. Covered haylage was superior to treated haylage in quality as measured by chemical analyses and …
Bedding As A Factor In The Survival And Total Height Of Two Year Old Planted Loblolly Pine Seedlings In East Texas, Edgar Wilkins
Bedding As A Factor In The Survival And Total Height Of Two Year Old Planted Loblolly Pine Seedlings In East Texas, Edgar Wilkins
Electronic Theses and Dissertations
With an ever increasing demand placed on wood fiber supply by industry, it has become imperative that every feasible means be pursued which will increase the wood fiber production per acre of land on every plantsble site. With this in mind, this study was conducted in an attempt to determine the effect of bedding in intensive site preparation on the total height and survival of two year old loblolly pine (Pinus taeda, L.) seedlings planted on bottomland and upland sites. Forty row (or lineal) plots 100 feet long were established on machine planted areas on bedded and unbedded, bottomland and …
Pisolithus Tinctorius Mycobiont Inoculations As A Factor In Performance Of Containerized And Bare-Root Shortleaf Pine Seedlings On Lignite Minesoils In Panola County, Texas, Hoy Lee Bryson
Electronic Theses and Dissertations
The effects of artificial soil infestation with basidiospores and vegetative mycelia of the fungal symbiont Pisolithus tinctorius on ectomycorrhizae development of short leaf pine (Pinus echinata) seedlings grown in styroblock containers were tested in the greenhouse. These preliminary tests showed that both spores and mycelia will produce satisfactory ectomycorrhizae development. Various methods of inoculation had little effect on growth and development of containerized seedlings or on the accumulation of N, P, K, Ca, Mg, Na, Mn, Zn, or Cu in foliage and lateral roots. The styroblock containerization system used in conjunction with sandy loam soil/vermiculite (2:1 v/v) potting-mix produced excellent …
Comparison Of Three Mass Media For Communicating Forestry Information For Young People, Ross Lee Tomlin
Comparison Of Three Mass Media For Communicating Forestry Information For Young People, Ross Lee Tomlin
Electronic Theses and Dissertations
A comparison of three mass media ( TV, radio and newspaper) was made to find which would be more effective at communicating forestry information to young people. The field study was conducted at Nacogdoches, Lufkin, and Kilgore High Schools in East Texas. Questionnaires given to students before and after exposure to six media spots tested forestry knowledge and attitudes. One spot in each medium presented a hardsell threat approach, the other a softsell-humorous approach. A final questionnaire measured student preferences of the media. Analysis of data indicated newspaper and TV to be the most effective media, with radio less effective. …
Duration Of Antibiotic Residues In Milk From Cows Treated Via Intrauterine And Intramammary Infusion, Elias Abdurahman
Duration Of Antibiotic Residues In Milk From Cows Treated Via Intrauterine And Intramammary Infusion, Elias Abdurahman
Electronic Theses and Dissertations
Antibiotics have been employed by farmers and veterinarians for treatment of infectious cattle diseases for over 3 decades. The most common of these diseases in dairy cows is mastitis. Mastitis is defined by the National Mastitis Council (NMC) (49) as an inflammation of the mammary gland. It is the most prevalent and most costly disease .of dairy cattle. It is estimated that at least 50% of all cows are infected with some form of mastitis at any one time in one or more quarters; cows in the average herd contract clinical mastitis one and one-half times per yr (49) which …
Heat-Treated Soybean Proteins For Lactating Dairy Cattle, Clayton D. Mielke
Heat-Treated Soybean Proteins For Lactating Dairy Cattle, Clayton D. Mielke
Electronic Theses and Dissertations
The value of heat treatment of protein supplements to reduce protein solubility and increase protein utilization was studied in two lactation trials. Experiment I was designed to study the utilization of heat-treated soybean meal (HSBM) by cows in early lactation. An extrusion process with moist heat was used to produce HSBM - a product with lower protein solubility than regular soybean meal (SBM). Ten cows, 3 wks post-partum, were assigned to treatments of HSBM or SBM. Due to a problem in feed bag labeling the concentrate mix containing SBM and corn was not as formulated. A large amount of ground …
Feeding Value Of High Protein Oat Silage Versus Corn Silage For Dairy Cows, Tilahun Sahlu
Feeding Value Of High Protein Oat Silage Versus Corn Silage For Dairy Cows, Tilahun Sahlu
Electronic Theses and Dissertations
Corn accounts for 80% of the total silage production in the United States while oats ranks second as a feed grain crop. Oats are a major crop in areas of the world where temperatures are cool and short growing seasons are not well suited for corn production. South Dakota is the leading oat producing state in the nation with 1. 68 million kilograms of oats produced annually. Oats play an important roll as animal feed because among common cereals in the United States it ranks highest in both protein and lysine content. Due to the wide genetic diversity of oat …
Soil Microfungal Relationships Associated With Grassland Reestablishment, Dennis C. Clarke
Soil Microfungal Relationships Associated With Grassland Reestablishment, Dennis C. Clarke
Electronic Theses and Dissertations
The mixed prairie association has a characteristic soil microfungal flora associated with the cover vegetation (Clarke and Christensen, 1980). Rhizosphere organisms are correlated with the cover vegetation (Christensen, 1969) and a change in the cover vegetation should be accompanied by a change in the organisms in the rhizosphere. Some disturbances that may lead to change in the cover vegetation are tillage, grazing, interseeding, mowing and fires. Christensen's (1980) review of species diversity and dominance in fungal communities indicates that in general these disturbances tend to reduce soil microfungal diversity while increasing the frequency of the remaining species. Other studies have …
A Computerized Planning Model For Small Farms In Southeastern South Dakota, Rodney Gene De Smet
A Computerized Planning Model For Small Farms In Southeastern South Dakota, Rodney Gene De Smet
Electronic Theses and Dissertations
Structural changes in agriculture resulting in fewer and larger farms carries strong implications for smaller farms. Included in the small farm group are small, low-resource, and part-time farmers, some of which are unable to generate an adequate income due to limited resources. This research study has developed a managerial tool for assisting low-resource farmers in developing optimal farm plans. The planning model is an interaction of familiar components (budgets) with a complex mathematical model (linear progra111T1ing) to provide an efficient analytical tool for use by farmers to aid in their managerial process. This study has placed emphasis upon the development …
Enantiomeric Influences In Neuroleptic Binding To Models Of The Dopamine Receptor, Timothy A. Robert
Enantiomeric Influences In Neuroleptic Binding To Models Of The Dopamine Receptor, Timothy A. Robert
Electronic Theses and Dissertations
No abstract provided.
A Comparison Of Cheddar Cheese Yields And Composition Using Conventional Bulk Set Cultures And Superstart Concentrated Cultures, William J. Kipp
A Comparison Of Cheddar Cheese Yields And Composition Using Conventional Bulk Set Cultures And Superstart Concentrated Cultures, William J. Kipp
Electronic Theses and Dissertations
The cheese industry has become by far the largest user of milk for manufacturing. In 1978, cheese production utilized a fourth of the total market supply of milk, up from less than an eighth in 1960 (4). Rising consumer incomes and changing lifestyles and eating habits have increased cheese consumption and sales by 60% since 1960 (21). In the last ten years, annual per capita consumption of cured cheese has increased from 11.6 lb to 17.1 lb (45). Economists state that the cheese market will continue to expand through the 1980's (7, 21, 68). Manufacturing cultured dairy products can be …
An Ultrastructural Study Of Fresh And Ensiled Alfalfa Using The Light And Transmission Electron Microscope, Janet Louise Lazo-Davis
An Ultrastructural Study Of Fresh And Ensiled Alfalfa Using The Light And Transmission Electron Microscope, Janet Louise Lazo-Davis
Electronic Theses and Dissertations
Late bud alfalfa was sampled prior to cutting and after 17 and 51 days of ensiling. Leaf and stem tissue were separated and immediately placed in 2.5% glutaraldehyde followed by 1% osmium textroxide for fixation. Following acetone dehydration, samples were embedded in Spurr plastic for examination under the light (LM) and transmission electron (TEM) microscopes. Light microscopy was used to differentiate cell types and tissues, e.g. epidermis, chlorenchyma, phloem, xylem, and pith. Iodine staining (LM) showed starch localization in chlorenchyma cells. Transmission electron microscopy analysis showed starch localized in chloroplasts of chlorenchyma. Leaf cells averaged nine chloroplasts per cell section …
Feeding And Housing Of Dairy Calves, Lester Vance Schaffer
Feeding And Housing Of Dairy Calves, Lester Vance Schaffer
Electronic Theses and Dissertations
In an 18 mo study antibiotic containing mastitic milk was collected from infected cows and fermented naturally for a minimum of 7 days at ambient temperature. Fermentation of antibiotic containing mastitic milk increased titratable acidity from 0.209% to 0.650% and decreased pH from 7.02 to 5.48. Fermentation decreased crude protein from 3.7% to 3.5% and increased NPN (% TN) from 6.0% to 8.4%. Penicillin was detected at a concentration of 1.2 IU/ml in the first milk after treatment and 0.01 IU/ml when fermented. Species of pathogenic organisms isolated from fresh and fermented milk were Staphylococcus epidermidis, Escherichia coli, Streptococcus dysgalactiae, …
The Effects Of Varying Dietary Protein, Calcium And Phosphorus In Starter Diets For Early Weaned Pigs, Wayne Eldon Schiefelbein
The Effects Of Varying Dietary Protein, Calcium And Phosphorus In Starter Diets For Early Weaned Pigs, Wayne Eldon Schiefelbein
Electronic Theses and Dissertations
Genetic selection by swine producers the past 10 to 15 years has resulted in faster growing, heavier muscled pig. In addition, confinement rearing has placed an increased emphasis upon skeletal development and bone formation. Recent research conducted at Ohio State University indicated that growing swine responded to increasing dietary protein levels if both calcium and phosphorus are also correspondingly increased but maintained at approximately a 1.3:1 ratio. This and other research has led some investigators to believe that the National Research Council's requirements for protein, calcium and phosphorus may not be adequate to support maximum growth and development. Much attention …
The Role Of Allelopathy On The Vegetational Composition Of Disturbed Sites On The Samuel H. Ordway Memorial Prairie, Randy C. Bartels
The Role Of Allelopathy On The Vegetational Composition Of Disturbed Sites On The Samuel H. Ordway Memorial Prairie, Randy C. Bartels
Electronic Theses and Dissertations
The presence of large numbers of cattle in prairie sites can lead to the trampling and destruction of native vegetation in some areas. These damaged, or disturbed sites are typically invaded by a variety of undesirable alien plant species. Many of the alien plant species possess allopathic mechanisms. These allopathic mechanisms enable the alien species to dominate the disturbed sites, and prevent the re-establishment of native plant species. Attempts are currently underway to preserve remaining tracts of native prairie in South Dakota. The Samuel H. Ordway, Jr. Memorial Prairie in McPherson county is one such tract, and is the research …
Utilization Of Aspen Pellets As A Partial Roughage Replacement For Lactating Dairy Cows, Deborah Sharples Kipp
Utilization Of Aspen Pellets As A Partial Roughage Replacement For Lactating Dairy Cows, Deborah Sharples Kipp
Electronic Theses and Dissertations
A complete switchback design using ten lactating cows divided into two groups of five was used to evaluate rations containing either (A) 30% dry matter from aspen pellets, 30% OM from corn silage, and 40% DM from a 28% crude protein· concentrate mix, or (B) 60% OM from corn silage and 40% OM from the concentrate mix, to determine if aspen could serve as a partial roughage for lactating dairy cows. All cows were at least 80 days into lactation at the start of the trial. Aspen contained on a DM basis, 1.9% crude protein, 80.3% neutral detergent fiber, 64.5% …
The Effect Of Sodium Hexametaphosphate On Cottage Cheese Yields, Stephen T. Dybing
The Effect Of Sodium Hexametaphosphate On Cottage Cheese Yields, Stephen T. Dybing
Electronic Theses and Dissertations
A major concern in the cottage cheese industry is the inefficient use of the available milk proteins. Currently, the methods of cottage cheese manufacture convert an average of only 74.9% of the milk proteins into cottage cheese, while the remainder are removed in the by-product whey (43, 56). As protein is the main determinant of both the yield and nutritional value of cottage cheese, if 25% of the available protein is lost to the whey, then potential cottage cheese yield and nutrition have been lost as well. The proteins lost in the whey are mainly -lactalbumin and β-lactoglobulin, which remain …
An Econometric Analysis Of The Cash Receipts From Crops In South Dakota, Dennis James Senger
An Econometric Analysis Of The Cash Receipts From Crops In South Dakota, Dennis James Senger
Electronic Theses and Dissertations
It is the intent of this research effort to fill a void left in the previous research efforts. This study will not be concerned with how farmers adjust production in response to price or government policies. The attempt will be made to adept single equation regression models to the examination of how the level of prices and supplies affect a major portion of the income farming sector receives, specifically the cash crop receipts. The specific objectives of this study are as follows: 1. To construct an economet5ric model of South Dakota crop receipts. 2. To demonstrate the model’s use as …
Hei-Gro Intravaginal Devices And Synovex-H Implants For Feedlot Heifers, James P. Goodman
Hei-Gro Intravaginal Devices And Synovex-H Implants For Feedlot Heifers, James P. Goodman
Electronic Theses and Dissertations
Heifers gain at a slower rate, generally require more feed per unit gain and sell at a lower market price than steers. Due to the fact that heifer carcasses are commonly fatter and contain more waste trim than steers, the value of a heifer carcass is routinely less than that of a steer carcass of comparable yield and quality grade. In the past, the ways in which the livestock operator could increase his profit from feeding heifers were limited. Differential cost of feeder heifers versus steers and feed cost were the major criteria involved in his decision of whether or …
Response Of Lactating Dairy Cows To Small And Large Amounts Of Dried Whey In The Concentrate Mixture, Eugene Walter Skyberg
Response Of Lactating Dairy Cows To Small And Large Amounts Of Dried Whey In The Concentrate Mixture, Eugene Walter Skyberg
Electronic Theses and Dissertations
Short-term (6 to 13 wk) experiments indicated that adding small amounts of dried whey to the concentrate mix fed to lactating dairy cows increase d milk fat percentage, but decreased milk production. In order to determine if the increased fat percentage was a positive response to dried whey in the ration, or an artifact of drying off the cows early, 5% dried whey product (DWP) was included in the concentrate mix fed to 10 Holstein cows. All cows started on the experiment in their 4th wk postpartum and continued for the duration of their lactation. The DWP replaced a portion …