1960-1969 Dissertations (MU)
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Item Morphology of the female reproductive organs of sea otters (Enhydra lutris L.)(University of Missouri--Columbia, 1965) Sinha, Akhouri Achyutanand; Conaway, Clinton H."The purpose of this study was to investigate the gross and microscopic anatomy of the reproductive organs of the female sea otter (Enhydra lutris L.) and relate them to the reproductive cycle. Emphasis has been given to ovarian histology. Although the value of the sea otter has been known to fur hunters for over two centuries, very little is known about this animal. Barabash-Nikiforov (1947) noted that sea otters have lentioulate shaped ovaries. Pearson (1952) studied a single pregnant sea otter and noted that the ovaries have irregular surface and subsurface fissures, besides the small Graafian follicles and a corpus luteun. The uterus was bipartite. Lensink (1962) briefly described reproduction in sea otters, based upon field observations."--Introduction.Item The influence of the bursa on Fabricius, spleen and thymus on the course of Plasmodium lophurae infections in chickens(University of Missouri--Columbia, 1968) Longenecker, Bryan M.; Breitenbach, Robert P."Splenectomized chicks were severely deficient in their ability to combat an infection or reinfection with Plasmodium lophurae. Infection of splenectomized chicks usually caused death while sham-operated controls recovered. Birds splenectomized on the 5th day of an infection, when parasitemias had dropped to a low level, showed an immediate and usually fatal recrudescence. Chicks which were hormonally or surgically bursectomized on the 1st day after hatching demonstrated higher parasitemias then their sham-operated controls. However, parasitemias of birds bursectomized at 18 days of age did not differ from their control group. Thymectomy had no significant effect on the resultant parasitemias. It is thus concluded that the spleen is of primary importance in the development of immunity to this strain of Plasmodium lophurae. The bursa is of secondary importance and contributes something to the development of the immune mechanism before 18 days of age. Bursaless birds demonstrated higher initial gamma-1, beta-1, beta-2, alpha-1 and alpha-2 values than sham operated control groups. These high mean values in the bursaless birds decreased during the malarial infection to a low level on about day four of the infection. The infected control group showed no decrease; in fact, an increase was often observed in this group. On the other hand, low albumin and gamma-2 titers were obtained in the bursaless groups. These altered protein changes were most apparent in the hormonally bursectomized groups, and especially in the thymectomized-hormonally bursectomized group. The plasma protein values of the thymectomized group were similiar to those of the sham operated infected birds. The major plasma protein response to the injected malarial parasites in the sham operated infected group was an increase in gamma-1 globulin. An early peak was noted on day two of the infection as well as an increase from day ten to fifteen. This response did not appear in any of the bursaless groups or in the non-infected group. The possible significance of a relationship between the high alpha and low gamma-2 globulin levels of bursaless birds is discussed. Antimalarial antibodies were detected in the plasma of normal birds which recovered from infection with P. lophurae. These antibodies were detected as specific antiparasitic agglutinins in normal birds. These agglutinins were not detected in the plasma of bursaless birds which had been infected and reinfected. The administration of hyperimmune plasma to bursaless and normal birds resulted in highly depressed parasitemias. Interestingly, infected bursaless birds which were given normal plasma from mature cockerels demonstrated parasitemias which were depressed to the level of parasitemias of intact infected birds. This indicated that bursaless birds lack a natural antibody which birds normally develop. Splenectomized-infected birds which received hyperimmune plasma eventually recovered from an infection. Splenectomized—controls, however, succumbed to the infection. The surviving splenectomized birds subsequently demonstrated an ability to control the parasites, as attempts to reinfect these birds failed. It was postulated that in the absence of the spleen and during intense antigenic stimulation, other lymphoid centers develop which are able to participate in normal anamnestic reactions."--Summary.Item Palynology of the Hannibal Formation (Lower Mississippian) of northeast Missouri and western Illinois(University of Missouri--Columbia, 1968) Brown, Dwight Delon"The purpose of this study is to describe and illus trate the miospore, acritarch, and Tasmanites assemblages which are present in the Lower Mississippian Hannibal Formation of northeast Missouri and western Illinois, and to determine the botanical, stratigraphical, and paleo-ecological significance of the assemblages. This research project was initiated in the summer of 1964 under the direction of Dr. J. M. Wood who foresaw the need to fill the void in palynological information regarding the occurrence of Mississippian miospores in Missouri sediments. The present study is the first report on the Lower Mississippian miospores of Missouri and Illinois. The one other report concerned with Lower Mississippian miospores in the United States is that of Winslow (1962). An abundant acritarch assemblage is reported here for the first time from the Lower Mississippian strata of North America."--Page 2.Item A study of the myxobacterial-eubacterial association(University of Missouri--Columbia, 1964) Brockman, Ellis R.; Peterson, John E."The myxobacteria are an unusual group of micro-organisms in many respects. One of the interesting aspects of these organisms is that many of them are closely associated with eubacteria; hence, they sometimes require a considerable amount of patience and skill to isolate into pure culture. (The word eubacteria will be used throughout this dissertation to describe the bacteria associated with myxobacteria, regardless of whether they belong to Order I., Pseudomonadales, or to Order IV., Eubacteriales, of the Division Protophyta.) Unlike most of the eubacteria with which they are often closely associated, the myxobacteria produce large quantities of polysaccharide slime around themselves. The abundance and nature of the slime, in which eubacteria are obviously often entrapped, no doubt hinders routine bacteriological purification techniques. The concept that myxobacteria are difficult to purify is not new, for scattered throughout the literature on the myxobacteria are numerous references that attest to this problem. Some of the most obvious of these references are: "difficulty in inducing it to grow pure" (Thaxter, 1097), "impurities" (Thaxter, 1904), "Rohkultur" (Baur, 1904), and "impure culture" (Kofler, 1913). One early reference (Pinoy, 1921) suggested that the relationship was more than a simple physical entrapment of the eubacterial cells in the slime surrounding the myxobacteria. Pinoy coined the name Synbacteria to encompass the myxobacteria and the associated eubacteria and, thereby, implied a symbiotic association between the myxobacteria and their associated eubacteria. Although this view must have seemed reasonable to Pinoy at the time, it was, nevertheless, quite illogical to classify two different organisms as one. Needless to say, the name Synbacteria has only historical significance today. The word association is defined in Webster’s dictionary as "anything closely or usually connected with another". This definition is accepted in this dissertation, and is implied whenever the word association is used to describe the myxobacterial-eubacterial relationship. References, both direct and indirect, have been made in the literature to the relatively constant association of myxobacteria and eubacteria, although little effort has been expended to elucidate the nature of this association. Therefore, the primary goal of the study reported here was to in vestigate the qualitative and quantitative aspects of the myxobacterial-eubacterial association. Essentially, this consisted of a compilation of the overall species-to-species relationship. As a secondary goal, the study investigated in more detail one particular association, that involving the fruiting myxobacterium, Myxococcus fulvus, and a Gram-negative eubacterium on which it was found growing, Alcaligenes viscolactis."--Introduction.Item The fossil flora of the drywood formation of southwestern Missouri(University of Missouri--Columbia, 1965) Basson, Philip Walter"The purpose of this study is to clarify and enlarge upon a previous research which defined the fossil flora of the Lower Coal Measures of Missouri. The former study was based almost entirely on materials that had been collected by individuals in Henry County, Missouri, who had forwarded the floral elements to Washington, D. C. for Identification. Since such collections usually are made up of better preserved materials rather than of all the taxa that may be present, it was felt that the previous collections may have contained a bias and hence the report did not give a complete picture of the flora. Recent information on the Rowe coal reveals an extensive area in which the stratum is exposed. It is questionable whether the previous study, based on a very limited area, gave a true representation of the fossil flora found stratigraphically between the Rowe coal and the Dry-wood coal. It is also questionable whether the strata were accurately defined if the specimens were mail order. Therefore, the major goals of this study were to collect plant macrofossils over a larger area to obtain a larger sample and to carefully define the strata from which these fossils were taken. Secondarily, the flora was also to be more carefully identified in light of the numerous studies made on the Pennsylvanian floras since the original work by White (1899). The flora will be compared with floras from other areas in order to determine similarities and to more clearly define the stratigraphic problems involved."--Introduction.