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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Molecular epidemiology of mycoplasma mastitis outbreak

Punyapornwithaya, Veerasak. January 2010 (has links) (PDF)
Thesis (Ph. D.)--Washington State University, May 2010. / Title from PDF title page (viewed on July 19, 2010). "College of Veterinary Medicine." Includes bibliographical references.
2

Immunological and physical studies of avian mycoplasmas

Aycardi, Eduardo. January 1970 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
3

Isolation, characterisation and molecular typing of feline mycoplasma species /

Robinson, Sally Rae. January 2009 (has links)
Thesis (M.V.Sc.)--University of Melbourne, Dept. of Veterinary Science, 2009. / Typescript. Includes bibliographical references.
4

Studies on the transmission of the poultry disease, infectious synovitis, by using direct contact and insect vector methods /

Peterson, Robert Victor, January 1961 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute, 1961. / Vita. Abstract. Includes bibliographical references (leaves 54-59). Also available via the Internet.
5

The role of Mycoplasma species in bovine respiratory disease complex in feedlot cattle in South Africa

Carrington, Christopher Antony Paul. January 2007 (has links)
Thesis (MMedVet (Production Animal Studies)--University of Pretoria, 2007. / Includes bibliographical references.
6

Microflora manipulation of artificially reared piglets

Schoenherr, William David January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
7

Preliminary investigations into ostrich mycoplasmas : identification of vaccine candidate genes and immunity elicited by poultry mycoplasma vaccines

Van der Merwe, Elizabeth Frances 12 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2006. / ENGLISH ABSTRACT: Ostrich farming is of significant economical importance in South Africa. Three ostrich mycoplasmas, Ms01, Ms02 and Ms03 have been identified previously, and were provisionally named ‘Mycoplasma struthiolus’ (Ms) after their host Struthio camelus. Ostrich mycoplasmas are the major causative organisms of respiratory diseases, and they cause stock losses, reduced production and hatchability, and downgrading of carcasses and therefore lead to large economic losses to the industry. In order to be pathogenic to their host, they need to attach through an attachment organelle, the so-called tip structure. This structure has been identified in the poultry mycoplasma, M. gallisepticum, and is made up of the adhesin GapA and adhesin-related CrmA. Currently, no ostrich mycoplasma vaccine is commercially available and for this reason the need to develop one has arisen. Therefore the first part of this study was dedicated to the identification and isolation of vaccine candidate genes in the three ostrich mycoplasmas. Four primer approaches for polymerase chain reactions (PCR’s), cloning and sequencing, were used for the identification of adhesin or adhesin-related genes from Ms01, Ms02 and Ms03. The primer approaches revealed that the target genes could not be identified due to the high diversity of sequences that were generated. Therefore sequences were also compared with those of other mycoplasma species in BLAST searches. Results showed that the most significant hit was with the human pathogen M. hominis oppD, which is located in the same operon as the membrane protein P100 involved in adhesion. Other hits were with ABC transporters which may also play a role in cytadhesion. The second part of this study was aimed at testing whether two poultry mycoplasma vaccines, M. synoviae and M. gallisepticum, can be used in ostriches to elicit immune responses until an ostrich mycoplasma vaccine has been developed. Ostriches on three farms of different age groups in the Oudsthoorn district were therefore vaccinated with these vaccines in a vaccine trial. The enzymelinked immunosorbent assay (ELISA) was used to test the level of antibody response. Results showed that both vaccines elicited an immune response in all three age groups. A high percentage of the ostriches reacted positively, which indicates that both vaccines elicit antibody responses and may therefore give protection against ostrich mycoplasma infections. / AFRIKAANSE OPSOMMING: Volstruisboerdery is ‘n belangrike ekonomiese sektor in Suid-Afrika. Drie volstruismikoplasmas, Ms01, Ms02 en Ms03, is voorheen geïdentifiseer en voorlopig ‘Mycoplasma struthiolus’ (Ms) benaam na aanleiding van hul gasheer, Struthio camelus. Volstruismikoplasmas is die grootste oorsaaklike organismes van respiratoriese siektes, kudde verliese en die afgradering van karkasse wat lei tot groot ekonomiese verliese in die volstruisbedryf. Ten einde patogenies vir die gasheer te wees, moet mikoplasmas deur middel van ‘n aanhegtingsmeganisme vasheg – die sogenaamde puntvormige struktuur. Hierdie struktuur is in die pluimvee mikoplasma M. gallisepticum geïdentifiseer, en bestaan uit aanhegting proteïen GapA en die aanhegting verwante proteïen CrmA. Tans is geen volstruismikoplasma entstof kommersieel beskikbaar nie, en derhalwe het die behoefte ontstaan om so ‘n entstof te ontwikkel. Die eerste gedeelte van hierdie studie is dus gewy aan die identifisering en isolering van entstof kandidaat gene in al drie volstruismikoplasmas. Vier inleier benaderings vir polimerase ketting reaksies (PKR), klonering asook geenopeenvolging bepalings vir die identifisering van aanhegting of aanhegting verwante gene vanuit Ms01, Ms02 en Ms03 is gebruik. Die inleier benaderings het getoon dat die teikengene nie geïdentifiseer kon word nie as gevolg van hoë variasie in die gegenereerde geenopeenvolgings. Derhalwe is geenopeenvolgings met ander mikoplasma spesies deur middel van BLAST soektogte vergelyk. Resultate het getoon dat die betekenisvolste ooreenstemming dié met die menslike patogeen M. hominis oppD was, wat deel vorm van die membraan proteïen P100 operon wat betrokke is by aanhegting. Ander ooreenstemmings sluit ABC transporters in wat moontlik betrokke kan wees by aanhegting. Die tweede gedeelte van hierdie studie het ten doel gehad om te toets of twee pluimvee mikoplasma entstowwe, M. synoviae en M. gallisepticum, gebruik kan word in volstruise om immuunresponse te ontlok tot tyd en wyl ‘n volstruismikoplasma entstof ontwikkel is. Volstruise vanaf drie plase in verskillende ouderdomsgroepe in die Oudtshoorn distrik was ingeënt met hierdie entstowwe in ‘n entstof proefneming. Die ensiem-afhanklike immuno-absorpsie essaï (ELISA) was gebruik om antiliggaam response te toets. Die resultate het getoon dat beide entstowwe immuunresponse ontlok het in al drie ouderdomsgroepe. ‘n Groot persentasie van die volstruise het positief gereageer wat ‘n aanduiding is dat beide entstowwe immuunresponse ontlok het en kan dus beskerming bied teen volstruismikoplasma infeksies.
8

The ostrich mycoplasma Ms02 partial genome assembly, bioinformatic analysis and the development of three DNA vaccines

Strydom, Marliz 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: The South African ostrich industry is under enormous threats due to diseases contracted by the ostriches. H5N2 virus (avian influenza) outbreaks the past two years have resulted in thousands of ostriches having to be culled. However, the more silent respiratory infectious agents of ostriches are the three ostrich-specific mycoplasmas. Named Ms01, Ms02, and Ms03, these three mycoplasmas are responsible for dramatic production losses each year, due to their intrusive nature and the fact that no vaccines are currently available to prevent mycoplasma infections in ostriches. The use of antibiotics does not eradicate the disease completely, but only alleviates symptoms. The ostrich industry commissioned investigations into the development of three specific vaccines using the relatively novel approach of DNA vaccination. The concept of DNA vaccine development is based on the availability of complete genome sequences of the pathogen against which the vaccine is to be developed. This is necessary in order to identify vaccine candidate genes through comparative genomic studies. The Ms02 genome has previously been sequenced, resulting in 28 large contiguous sequences. This thesis used the technique of Thermal Asymmetric Interlaced Polymerase Chain Reaction (TAIL-PCR) to attempt assembly of these 28 contiguous sequences. The number was reduced to 14 large contiguous sequences, which were then subjected to repetitive sequence analysis and open reading frame analysis. Bioinformatic software was also used to predict the origin of replication. The extent of repeats in the Ms02 genome is illustrated, as well as the problems with genome assembly when dealing with repetitive-rich and A+T-rich genomes as those of mycoplasmas. Previous studies determined the mycoplasma oppA gene to be a good vaccine candidate gene, due to its cytadherent properties. This thesis describes the development of three DNA vaccines containing the Ms02 oppA gene, and a preliminary attempt to prove expression of one of these vaccines in a cell culture-based system. The DNA vaccine vectors pCI-neo, VR1012, and VR1020 were chosen for the vaccine development. The Ms02 oppA gene was also cloned into the prokaryotic expression vector pGEX-4T-1 in order to express the OppA protein for purification. The purified protein may be used in future serological tests in ostrich vaccination trials. In this study the protein was used to elicit anti-OppA rabbit antibodies, which were used to attempt detection of the pCI-neo-driven OppA protein expression in an MDA cell line in a transfection study. However, preliminary findings could not detect expression, but did indicate that the currently used colorimetric western blot technique may not be sensitive enough. It is suggested that different cell lines need to be investigated. Further optimisations are also required to decrease the observed non-specific binding. / AFRIKAANSE OPSOMMING: Die Suid-Afrikaanse volstruisbedryf is onder geweldige druk vanweë siektes wat die volstruise bedreig. Die epidemie van die H5N2 virus (voëlgriep) in die afgelope twee jaar het veroorsaak dat duisende volstruise van kant gemaak moes word. Daar is egter nog ‘n bedreiging wat tot geweldige produksie verliese lei elke jaar: die respiratoriese infeksies wat versoorsaak word deur die drie volstruis mikoplasmas, genoem Ms01, Ms02 en Ms03. Geen entstowwe is tans beskibaar om die infeksies te voorkom nie, en behandeling met behulp van antibiotikas is nie effektief in die genesing van infeksie nie, maar help net om die simptome te verlig. Weens die erns van die saak, het die Suid-Afrikaanse volstruisbedryf ‘n ondersoek geloods na die ontwikkeling van enstowwe teen elkeen van die drie volstruis mikoplasmas. Die relatiewe nuwe benadering van DNA-entstof ontwikkeling was die strategiese keuse. Die beginsel van DNA-entstof ontwikkeling berus op die beskikbaarheid van die genoomvolgordes van die siekte-veroorsakende organisme waarteen die enstof ontwikkel word. Geskikte kandidaat entstof gene word so opgespoor met behulp van vergelykende studies met ander beskikbare genome. Die Ms02 genoomvolgorde is voorheen bepaal en word verteenwoordig deur 28 groot geenvolgorde fragmente. Die tegniek van Thermal Asymmetric Interlaced Polymerase Chain Reaction (TAIL-PCR) is gebruik om van die 28 fragmente aan mekaar te las. Die aantal fragmente is verminder na 14 groot geenvolgorde fragmente, wat vervolgens gebruik was om die omvang van herhalende volgordes in die genoom te bepaal, om nuwe leesrame te ondersoek, asook om die oorsprong van DNA replikasie op te spoor met behulp van bioinformatika sagteware. Die omvang van die herhalende aard van die Ms02 genoom word geïllustreer, asook die gepaardgaande probleme met die las van geenvolgorde fragmente wanneer met genome van veelvuldige herhalende volgordes, wat boonop A+T-ryk is, gewerk word, soos die van mikoplasmas. Vorige studies het die mikoplasma oppA geen geïdentifiseer as ‘n geskikte kandidaat entstof geen as gevolg van sy selaanhegting-eienskappe. Hierdie studie behels die invoeging van die Ms02 oppA geen in drie DNA-enstof vektore, naamlik pCI-neo, VR1012, en VR1020, asook die voorlopige poging om bewys van uitdrukking van een van die entstowwe in ‘n selkultuursisteem te bewerkstellig. Die geen is ook gekloneer in die prokariotiese ekspressie vektor pGEX-4T-1, ten einde die Ms02 OppA proteïen te isoleer. Die geïsoleerde proteïen kan in serologiese toetse in toekomstige volstruis enstof proewe gebruik word. In hierdie studie is die proteïen gebruik om konyn teenliggame teen dit op te wek, wat dan gebruik was om vir die pCI-neo-gedrewe ekspressie van die oppA geen te toets in ‘n selkultuur omgewing deur ‘n MDA sellyn te transfekteer. Die voorlopige resultate toon nie ekspressie van die OppA proteïen aan nie, maar het wel uitgelig dat die western blot tegniek wat tans gebruik word, dalk nie sensitief genoeg is nie. Dit kan belowend wees om ander tipes selle te toets. Verdere optimisering is ook nodig om die nie-spesifieke binding wat waargeneem is, te verlaag. / South African Ostrich Business Chamber
9

Studies on the transmission of the poultry disease, infectious synovitis, by using direct contact and insect vector methods

Peterson, Robert Victor 03 October 2008 (has links)
The possibilities of transmission of infectious synovitis were explored. Two types of tests, using mosquitoes as vectors, were employed. One type involved the feedings of mosquitoes on previously inoculated birds, then after a period of from zero to ninety-six hours refeeding the mosquitoes on assay birds. The second type of insect test comprised the feeding of mosquitoes on inoculated birds, then macerating and inoculating them into check birds at intervals of one to twenty-one days following feeding. Other experiments were conducted in which uninoculated birds were brought into close contact with inoculated chickens and their excrement. The observation of all tests indicated the absence of transmission of an infective titer of the infectious synovitis agent. These conclusions are drawn from tests using Aedes aegypti (Linn.) and Culex fatigans Wied., with methods and materials described. / Master of Science
10

Immunological and epidemiological investigations in South African ostriches and penguins

Botes, Annelise 04 1900 (has links)
Dissertation (PhD)--University of Stellenbosch, 2004 / ENGLISH ABSTRACT: Newcastle disease (NO) and mycoplasma infections in ostriches have considerable economic implications for the South African ostrich industry in that NO is a limiting factor in the export of ostrich products to the European Union and mycoplasma infections cause stock losses, reduced production, reduced hatchability and downgrading of carcasses. In the first section of this dissertation, the role of passively acquired and mucosal immunity in protection of ostrich chicks against Newcastle disease virus (NOV) was investigated. Ostrich hen serum IgG and yolk IgY were isolated and characterized, and the transfer of maternal anti-NOV antibodies to the egg yolk was determined using an enzyme-linked immunosorbent assay (ELISA). Results indicated that anti-NOV antibodies were successfully transferred from the ostrich hen to the egg yolk. In addition, ostrich IgA was isolated, characterized and rabbit anti-ostrich IgA antibodies produced and used for measuring mucosal anti- NOV IgA antibodies produced in response to mucosal vaccination. Results indicated that the live La Sota vaccine stimulates IgA production and thus mucosal immunity in ostrich chicks. In the second section of this dissertation, ostrich mycoplasmas were isolated and identified using 16S rRNA gene sequencing. These sequences indicated that ostriches carry three unique mycoplasmas, which are phylogenetically quite divergent. The 16S rRNA gene sequences of the ostrich mycoplasmas were subsequently used for the development of specific primers for the detection and diagnosis of mycoplasma infections in ostriches by PCR. The last section of this dissertation focuses on avian malaria in African penguins and the management of this disease during rehabilitation. The Foundation for the Conservation of Coastal Birds (SANCCOB) is a seabird rescue and rehabilitation centre, which is largely dedicated to the rehabilitation of diseased, injured and oiled penguins. Significant mortalities due to avian malaria occur at this facility. The aim of this study was the development of an ELISA for the purpose of assessing the natural levels of anti-Plasmodium antibodies in African penguins on entry into the SANCCOB facility and during rehabilitation. Results indicated significant increases in anti- Plasmodium antibody levels after entry, which was not influenced by oiling. Infection with malaria and not parasite recrudescence was viewed to be the cause of this increase, indicating a possible role of the SANCCOB facility in exposing penguins to avian malaria. / AFRIKAANSE OPSOMMING: Newcastlesiekte (NS) en mikoplasmainfeksies in voltruise het geweldige ekonomiese implikasies vir die Suid-Afrikaanse volstruisbedryf. Die rede hiervoor is dat NS 'n beperkende faktor in die uitvoer van volstruisprodukte na die Europese Unie is, en mikoplasmainfeksies tot kudde verliese, verlaagde produksie en uitbroei asook lae gradering van karkasse lei. In die eerste gedeelte van hierdie proefskrif is die rol van passiewe- en mukosale-immuniteit in die beskerming van volstruiskuikens teen NS virus (NSV) ondersoek. Volstruishenserum IgG en eier IgY is geïsoleer en gekarakteriseer en die oordrag van maternale anti-NSV antiliggame na die eier ondersoek met behulp van 'n 'enzyme-linked immunosorbent assay' (ELISA). Resultate het getoon dat anti-NSV antiliggame suksesvol van die hen na die eier oorgedra is. Volstruis IgA is ook geïsoleer, gekarateriseer en konyn anti-volstruis IgA antiliggame geproduseer wat gebruik is vir die bepaling van mukosale anti-NSV IgA antiliggame in reaksie op mukosale immunisering. Resultate het getoon dat lewendige La Sota entstof IgA produksie stimuleer en dus tot mukosale-immuniteit in volstruiskuikens lei. In die tweede gedeelte van hierdie proefskrif is volstruismikoplasmas geïsoleer en geïdentifiseer met behulp van 16S rRNA geenopeenvolgingsbepalings. Hierdie volgordes het getoon dat drie unieke mikoplasmas in volstruise voorkom wat filogeneties verskillend blyk te wees. Die 16S rRNA geenopeenvolgings van die volstruismikoplasmas is gebruik vir die ontwikkeling van spesifieke inleiers vir die PKR identifisering en diagnose van mikoplasmainfeksies in volstruise. Die laaste gedeelte van hierdie proefskrif fokus op voëlmalaria in die Afrika pikkewyn en die bestuur van hierdie siekte gedurende rehabilitasie. Die 'South African Foundation for the Conservation of Coastal Birds' (SANCCOB) is 'n seevoëlreddingsen rehabilitasie-sentrum vir siek, beseerde en ge-oliede pikkewyne. Hierdie sentrum het egter aansienlike vrektes as gevolg van voëlmalaria. In hierdie studie is 'n ELISA ontwikkel vir die bepaling van natuurlike anti-Plasmodium antiliggaamvlakke van pikkewyne by aankoms en tydens rehabilitasie by SANCCOB. Resultate het 'n toename in anti-Plasmodium antiliggaamvlakke getoon na toelating wat nie beïnvloed is deur olie nie. Hierdie toename kan toegeskryf word aan nuwe malariainfeksies en nie 'n heruitbraak van bestaande infeksies nie wat daarop dui dat pikkewyne aan voëlmalaria blootgestel word by die SANCCOB-sentrum.

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