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.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/53747 |
| Date | 04 1900 |
| Creators | Botes, Annelise |
| Contributors | Bellstedt, D. U., Stellenbosch University. Faculty of Science. Dept. of Biochemistry |
| Publisher | Stellenbosch : Stellenbosch University |
| Source Sets | South African National ETD Portal |
| Language | en_ZA |
| Detected Language | Unknown |
| Type | Thesis |
| Format | 237 p. : ill. |
| Rights | Stellenbosch University |
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