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Articles 3061 - 3090 of 3160
Full-Text Articles in Life Sciences
The Effects Of Relaxin On The Composition Of Bovine Milk, Chris H. Nissen
The Effects Of Relaxin On The Composition Of Bovine Milk, Chris H. Nissen
Electronic Theses and Dissertations
Protoplasm is a fragile substance keeping its homeostatic properties by many physiochemical phenomena. Much is known about the properties of protoplasm; but it is, perhaps, only meager when compared to what is yet to be learned. Such physical changes as electrical impulses, diffusion, and oxidation – to mention a few – are necessary for protoplasm to retain its integrity. In higher animals, particularity, for our purpose, mammals, protoplasm is sustained by different body system working harmoniously together to supply raw materials that remove waste, and govern all endeavors. One should not infer that single called animals have a more simple …
The Blood Picture In Correlation With Bloat, Dale A. Yarns
The Blood Picture In Correlation With Bloat, Dale A. Yarns
Electronic Theses and Dissertations
Bloat may spell disaster to any farmer on a given day. This kind of disaster is typical and not infrequent in ruminates especially cattle and sheep. Bloat affects polygastrics, why not monogastrics? Ruminants or polygastrics have a four compartment stomach utilizing protozoa and bacteria similar to a fermentation vat which catabolizes complex substrates into simple digestible nutrients while the monogastrics rely on secretions from the stomach lining. Primarily fermentation takes are water and larger amount of free gas, which can accumulate in the rumen when disposal is impaired. Why do animals dispose of these large quantities of gas 364 days …
Consumer Preferences And Attitudes Toward Butter And Advertising In Brookings And Madison, South Dakota, Paul M. Williamson
Consumer Preferences And Attitudes Toward Butter And Advertising In Brookings And Madison, South Dakota, Paul M. Williamson
Electronic Theses and Dissertations
The basic purpose of this study was to seek means of improving the incomes of dairy farmers through the development of better markets for butter. In line with this, three major hypotheses were tested. The hypotheses were: (1) a sufficient proportion of consumers in Brookings and Madison prefer cultured butter to make it feasible to develop a market for it, (2) consumption of cultured butter can be increased by sales promotion, (3) development of a market for cultured butter will increase total butter consumption.
An Attempt To Develop Resistance In The Udder Against Streptococcus Dysgalactiae And Escherichia Coli, Donald E. Otterby
An Attempt To Develop Resistance In The Udder Against Streptococcus Dysgalactiae And Escherichia Coli, Donald E. Otterby
Electronic Theses and Dissertations
The problem of mastitis in dairy animals has received much attention in recent years. As the business of dairying has developed and grown, mastitis has become more significant to the farmer and the processor. The economic loss from reduced production and sale of milk, loss of breeding animals, veterinary and medical fees is paramount. Much of the emphasis when dealing with mastitis has been on cure rather than prevention. Despite the extensive investigations of antibiotics and other chemo-therapeutic agents as a cure for mastitis, a completely satisfactory answer to the mastitis problem has not been found. Recent research has suggested …
Some Observations Pertaining To The Effects Of Relaxin Upon The Bovine, Vincent Allen Hall
Some Observations Pertaining To The Effects Of Relaxin Upon The Bovine, Vincent Allen Hall
Electronic Theses and Dissertations
The process of birth normally follows a set pattern. The main steps in chronological order are: labor, opening of the cervix, and delivering the young. The cervix serves an important function in reproduction. The cervix is the constricted portion separating the uterus and the vagina, and consists primarily of thick connective tissues especially constructed in folds forming a hollow tube. Through the cervix passes sperm, menstrual debris and in pregnancy the newborn. During pregnancy a mucous plug forms in the cervix and keeps out foreign material and bacteria. In the non-pregnant cow the opening is small. The cervix opening is …
Bloat Results From Various Drenchings Including Effectiveness Of Penicillin For Prevention, Clarence Leonard Moore
Bloat Results From Various Drenchings Including Effectiveness Of Penicillin For Prevention, Clarence Leonard Moore
Electronic Theses and Dissertations
Body conformation is associated with function among all classes of livestock. Dairy cattle type deals with characteristics indicating ability to produce milk and butterfat economically along with breed character and other values of an aesthetic nature. In order to have economical milk and butterfat production, the dairy cow should possess that type of body conformation which is able to withstand the rigors of disease, reproduction and year after year milk production. A large percentage of dairy cattle sold in South Dakota and surrounding territory, whether for breeding purpose or commercial production, are evaluated primarily on the basis of their type. …
A Genetic Analysis Of Economic Characteristics Of Range Beef Heifers, Keith O. Zoellner
A Genetic Analysis Of Economic Characteristics Of Range Beef Heifers, Keith O. Zoellner
Electronic Theses and Dissertations
The beef cattle industry is one og the major sources of rural income in South Dakota. According to the South Dakota Crop and Livestock Reporting Services (1956), there were 1,492,000 beef cows and yearling beef heifers on the farms and ranches in South Dakota as of January 1, 1957. They also reported that sales from cattle and calves amounted to approximately 34.6 percent of the gross farm and ranch income in the state. Since the beef cattle industry is a major source of the farm and ranch income in South Dakota, any improvement in the performance of beef cattle will …
The Effects Of Low Temperature On Survival Of Rabbit Ova, Mansur Ferdows
The Effects Of Low Temperature On Survival Of Rabbit Ova, Mansur Ferdows
Electronic Theses and Dissertations
In the field of animal production, genetic characteristics determine to a large extent the quality and the economy of the cattle. To hasten the wide spread dissemination of germ plasm, many commercial farmers have resorted to artificial insemination. Artificial insemination has however, only allowed for the wide spread dissemination of germ plasm from the male. If the female germ plasm could also be more easily disseminated through the highly experimental process of ova transfer, then more than the average number of offspring could be expected from a female in her life time. Because ova transplantation is in its infancy, many …
Growth And Respiratory Studies Of Saccaromyces Cerevisiae In The Presence Of Selenium, Robert M. Pengra
Growth And Respiratory Studies Of Saccaromyces Cerevisiae In The Presence Of Selenium, Robert M. Pengra
Electronic Theses and Dissertations
The occurrence of selenium in certain soils of the United States and its detrimental effect upon livestock pastured on or fed forage from these areas has been well established. Selenium poisoning will not be reviewed here as several excellent reviews have been published (1, 2, 3). Studies on the metabolism of selenium by Sac-charomyces cerevisiae have been reported by Potter and Elvehjem (4), Lardy and Moxon (5), and Fels and Cheldelin (6, 7, 8). An attempt has been made in this thesis to repeat and enlarge on some of these studies. While this investigation may contribute information on the selenium …
The Improvement In Type Of South Dakota Dairy Cattle Through Artificial Breeding, Kenneth I. Gross
The Improvement In Type Of South Dakota Dairy Cattle Through Artificial Breeding, Kenneth I. Gross
Electronic Theses and Dissertations
Body conformation is associated with function among all classes of livestock. Dairy cattle type deals with characteristics indicating ability to produce milk and butterfat economically along with breed character and other values of an aesthetic nature. In order to have economical milk and butterfat production, the dairy cow should possess that type of body conformation which is able to withstand the rigors of disease, reproduction and year after year milk production. A large percentage of dairy cattle sold in South Dakota and surrounding territory, whether for breeding purpose or commercial production, are evaluated primarily on the basis of their type. …
Some Mechanical And Horomonal Methods Of Dilating The Bovine Cervix, Edmund F. Graham
Some Mechanical And Horomonal Methods Of Dilating The Bovine Cervix, Edmund F. Graham
Electronic Theses and Dissertations
The selection for certain inherited characteristics war practiced approximately 2000 years before the Christian Era. Jacob (Genesis 30:28-43) was given all the speckled cattle in his master’s herd for being herdsman. In a few years, by selecting for the spotting factor, only speckled cattle remained in the herd. Selection was the first tool for segregating definite characteristics. As a means of more rapid improvement artificial insemination was practiced by an Arabian chieftain as early as 1322 A. D. (35). Since 1322 these crude methods of transferring semen have been perfected until approximately four million cows were inseminated in the United …
A Study Of Bovine Noseprints, Morris W. Hirsch
A Study Of Bovine Noseprints, Morris W. Hirsch
Electronic Theses and Dissertations
The breed association are continuously confronted with the problem of properly identifying animals for registration. The method of identifying the broken color breeds, such as Guernseys, Holsteins, and Ayrshires, is by a sketch of the color patterns which accompanies the application for registration. This has been fairly successful, but due to the poor drawing ability of the applicant approximately twenty percent of animal markings and sketch do not resemble each other to establish identity. The solid colored breeds use brands or tattoo marks in the ear which are not entirely satisfactory since these are artificial and can be applied in …
A Survey Of The Microflora Obtained By Flushing The Normal Bovine Uterus, Johannah Jane Wulf
A Survey Of The Microflora Obtained By Flushing The Normal Bovine Uterus, Johannah Jane Wulf
Electronic Theses and Dissertations
Since artificial insemination has become a reality and the potentialities of ova transfer are being investigated by several research workers, it seems reasonable to assume that some attention should be directed toward gathering information regarding the bacterial flora of the normal bovine uterus. Both artificial insemination and ova transfer require the insertion of foreign bodies or instruments into the uterus. When such instruments enter this organ, there is always the possibility of introducing various kinds of bacteria. Very little information is available regarding the pathogenicity of these bacteria in the bovine uterus. The possibility of abortion due to such pathogenic …
Influence Of Winter Housing Conditions On Growth Rates And Feed Consumption Of Dairy Heifers, Emery H. Bartle
Influence Of Winter Housing Conditions On Growth Rates And Feed Consumption Of Dairy Heifers, Emery H. Bartle
Electronic Theses and Dissertations
It is important in dairy cattle management to maintain steady and continuous growth of heifers and thereby secure properly developed cows which will give the production that is expected of them when they are brought into the milking herd. In general, heifer calves during the first twelve months of their growing period are carefully managed as to feed, housing and care to promote normal growth. However, they are often neglected during their yearling stage to the point where growth is retarded because of environment factors. On many dairy farms in the North Central States the management of yearling dairy heifers …
Agarics Of The Louisville Area : A Taxonomical Problem., Eugene H. P. Mondeau
Agarics Of The Louisville Area : A Taxonomical Problem., Eugene H. P. Mondeau
Electronic Theses and Dissertations
No abstract provided.
Separation Of The Selenium Compounds In Seleniferous Plant Protein Hydrolysates By Paper Partition Chromatography, Arnold L. Smith
Separation Of The Selenium Compounds In Seleniferous Plant Protein Hydrolysates By Paper Partition Chromatography, Arnold L. Smith
Electronic Theses and Dissertations
In 1943 Franke reported that the protein of "allolied" or "toxic" wheat carried the toxicant, and Franke and Painter in 1935 reported that those "toxic" proteins contained selenium which was in organic combination in the protein. There has been much speculation regarding the possibility of selenium replacing sulfur in the amino acids cysteine and methionine. The toxicity of selenium in selenium analogs of these compounds is similar to that of selenium occurring naturally in proteins seleniferous cereals, which indicated that the selenium may be present in the proteins as the analogue of these sulfur amino acids.
Systems Of Producing Fat Yearlings For South Dakota, William Clark Mccone
Systems Of Producing Fat Yearlings For South Dakota, William Clark Mccone
Electronic Theses and Dissertations
About twelve billion pounds of dressed beef and veal were produced in the United States in 1947 through the conversion of grassland crops into meat by cattle and these cattle lead all classes of American livestock in the consumption of grass and grassland crops. Grass usually represents the principal and cheapest feed for beef cattle. They utilize about one third of the permanent pastures and three fourths of the range areas. Pastures may be regarded as a costly source of feed only on highly productive farm lands, but their use in rotation with cultivated crops on such land is certain …
The Apparent Digestibility By Sheep Of Prairie Hay Harvested At Three Stages Of Maturity, Robert Manseau Jordan
The Apparent Digestibility By Sheep Of Prairie Hay Harvested At Three Stages Of Maturity, Robert Manseau Jordan
Electronic Theses and Dissertations
Grass is the greatest asset of the Northern Great Plains. Grass does and must serve as the basic feed for the flocks and herds of this area. Without grass, much of the Northern Great Plains would be waste land with little or no value. In the states of North and South Dakota, Nebraska, Colorado, Wyoming, and Montana, about 67 per cent of the total land is in pasture and hay. Seventy five to 95 per cent of the total feed needed by cattle and sheep in the Northern Plains states is furnished by pasture and roughage. With an ever-increasing demand …
A Study Of The Heel Flies, Hypodermia Lineatum Devillers And Hypoderma Novis Degeer, In South Dakota, John A. Lofgren
A Study Of The Heel Flies, Hypodermia Lineatum Devillers And Hypoderma Novis Degeer, In South Dakota, John A. Lofgren
Electronic Theses and Dissertations
The heel flies or ox-warble flies and their larvae, commonly called cattle grubs or warbles, are among the most troublesome and costly insect pests of livestock producers in South Dakota. These parasites attack cattle almost exclusively although they may occur at times in other domestic and in wild animals. Infestations in man have been recorded, but these cases are quite rare. This work deals only with the occurrence of the parasites in cattle.
The Effect Of Age Of Gilt On Size Of Litter, Clifford Inman Iverson
The Effect Of Age Of Gilt On Size Of Litter, Clifford Inman Iverson
Electronic Theses and Dissertations
Size of litter is an important consideration in determining the profits from a swine production enterprise. Basic information concerning factors affecting litter size is, therefore, pertinent to the swine production industry. This study was conducted to ascertain the effect of age of gilt on the size of their first litters.
Distribution Of The Herpetofauna Of Kentucky., Symoine Kamin Laufe
Distribution Of The Herpetofauna Of Kentucky., Symoine Kamin Laufe
Electronic Theses and Dissertations
Although the herpetofauna of Kentucky is extensive and varied. it has received much less attention than that of most other states. Many herpetologists have reported on various phases of the state's amphibians and reptiles, but for the most part these reports are discrete, either pertaining to a collection, or a generic or specific study. Hence, there is no single adequate work which aptly describes the herpetology of Kentucky as a whole. When one realizes the keystone position of Kentucky in relation to northern and southern forms, the need of a zoogeographical summary of the state becomes even more apparent. Therefore, …
Methemoglobin., Herbert Friedman
Methemoglobin., Herbert Friedman
Electronic Theses and Dissertations
No abstract provided.
The Yielding Ability Of Bulked F2 Barley Crosses And Parents In Comparative Yield Trials, Walter Lowell Nelson
The Yielding Ability Of Bulked F2 Barley Crosses And Parents In Comparative Yield Trials, Walter Lowell Nelson
Electronic Theses and Dissertations
Present methods of breeding new barley varieties are costly, laborious and lengthy. Populations from a cross are grown until they become homozygous before much selection by comparative yield trails can be made. The pedigree method limits the number of crosses that can be studied because of the large segregating populations necessary for the expression of desired gene combinations. Because of the enormous amount of work involved, it would be highly desirable for a plant breeder to work only with superior parental material. The capabilities of a plant breeder would be greatly increased by an method which would allow him to …
The Apparent Digestibility Of Prairie Hay Harvested At Three Stages Of Maturity, Arnold Bernard Nelson
The Apparent Digestibility Of Prairie Hay Harvested At Three Stages Of Maturity, Arnold Bernard Nelson
Electronic Theses and Dissertations
More land in the United States is used for grazing and hay production than for all other farm crops grown. Well-managed pastures and rangeland have always been recognized as an economical source of feed and recently have commanded much attention as an effective means of conserving soil resources and preventing erosion. In the states if North and South Dakota, Nebraska, Colorado, Wyoming and Montana, about 67 per cent of the total land in farms and ranches is in pasture and hay. Over 60 per cent of the entire area of South Dakota and about 83 per cent of the area …
Carcass Differences In Inbred Lines And Linecrosses Of Swine, Ellis Andine Pierce
Carcass Differences In Inbred Lines And Linecrosses Of Swine, Ellis Andine Pierce
Electronic Theses and Dissertations
A great amount of variation in the carcasses from butcher hogs proximal to two hundred and twenty pounds from different lines and breeds has become apparent in recent years. The average hog producer prefers the type of hog that gains quickly and economically and will net the most profit. The average consumer, however, prefers the type of carcass that has a high percentage of lean to fat. Today the dollar value of market hogs is determined more by the amount of finish they are carrying than by the quality of carcass. Since variations do exist in the carcasses from different …
Studies On Synthesis By Enzymatic Catalysis., Charles Henry Wabnitz 1916-2004
Studies On Synthesis By Enzymatic Catalysis., Charles Henry Wabnitz 1916-2004
Electronic Theses and Dissertations
No abstract provided.
The Nature Of The Amenorrhea Of Lactation In Humans., Carroll H. Luhr
The Nature Of The Amenorrhea Of Lactation In Humans., Carroll H. Luhr
Electronic Theses and Dissertations
No abstract provided.
A Survey Of The Rhopalocera Of Jefferson County, Kentucky., Delbert Kenneth Weniger
A Survey Of The Rhopalocera Of Jefferson County, Kentucky., Delbert Kenneth Weniger
Electronic Theses and Dissertations
No abstract provided.
Abstracts Of Source Materials On The Conservation Of Our Natural Resources., Eunice Wheeler Duncan
Abstracts Of Source Materials On The Conservation Of Our Natural Resources., Eunice Wheeler Duncan
Electronic Theses and Dissertations
No abstract provided.
A Study Of Factors Influencing The Hydrolysis Of Corn Amylopectin By Barley Malt Enzymes., Thelma Munsey Back 1918-2006
A Study Of Factors Influencing The Hydrolysis Of Corn Amylopectin By Barley Malt Enzymes., Thelma Munsey Back 1918-2006
Electronic Theses and Dissertations
No abstract provided.