This thesis comprises an introductory review of the literature, followed by reports of two experiments which are presented in the form of scientific papers. For this reason, there may be some repetition between chapters, particularly in terms of experimental procedure. To avoid unnecessary repetition, a single list of references is given at the end of the thesis. For the sake of completeness , several appendices are attached to Chapters Two and Three which would not ordinarily be included in a scientific paper. The literature review looks at the passive transfer of immunity from the mare to the foal, the consequences of failure of passive transfer of immunity and different methods of testing whether the transfer of passive immunity has occurred. The review concludes with a discussion of vaccination programmes against African horse sickness. Trial One evaluated different tests for determining whether the transfer of passive immunity from mare to foal has occurred in order to determine which of these tests should be used preferentially. A single radial immunodiffusion test was used as the reference standard. A series of samples .was taken from a group of foals and tested using four methods: single radial immunodiffusion , glutaraldehyde coagulation, zinc sulphate turbidity and protein refractometer tests. Trial Two explored African horse sickness vaccination programmes, focusing on when to vaccinate foals for the first time. A series of samples was taken from a group of foals from birth until two months after their second set of African horse sickness vaccinations (one year old). The samples were tested for the presence of African horse sickness antibodies for each of the nine serotypes to determine when maternal immunity fades and to evaluate the effect of each vaccination on the level of immunity. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.

CAPES / O presente trabalho tem por objetivo apresentar uma nova técnica de instrumentação para estudo dos diferentes tipos de andaduras realizadas por equinos, utilizando sistemas baseados na tecnologia de sensoriamento ótico quase-distribuído, redes de Bragg em fibra ótica-FBG. Essa técnica poderá ser usada como ferramenta auxiliar de diagnóstico precoce de lesões relacionadas ao sistema locomotor do cavalo, principalmente na porção distal do dígito, uma das causas mais comuns de aposentadoria destes quando atletas. São apresentadas, portanto, duas técnicas de instrumentação in vivo: a primeira t´técnica consiste na fixação de FBGs sem encapsulamento, diretamente na parede dorsal do casco em cada um dos membros de três cavalos atletas em treinamento; a segunda técnica apresentada ´e o desenvolvimento de um protótipo sensor com formato de ferradura encapsulado em material compósito reforçado com fibra de carbono, este método foi utilizado na instrumentação de dois equinos também em fase de treinamento. O primeiro método permite avaliar o comportamento do casco em diferentes fases da passada, durante as andaduras passo e trote. A segunda técnica, com o elemento sensor encapsulado, permite avaliar diferentes tipos de andadura, como passo, trote e galope sob condições de treinamento. Estas duas técnicas de instrumentação, utilizando sensores FBGs, se mostram promissoras para o estudo clínico e biomecânico de equinos, em avaliações m´médicas ou até mesmo durante treinamentos ou competições. / The main goal of this paper is to study the viability of the application of the system based on the optic sensing almost distribute (Fiber Bragg Gratings-FBG) technology, to study different kinds of equine gaits and how it is a possible helpful tool to early diagnose of injuries related to the locomotor system of the horse, mainly the distal part of the digit, which is one of the most common reasons for retire of athlete horses. Two different technics are presented in vivo: The first one consists in the attachment of the FBGs without encapsulation, directly on the wall of the hoof of each member of three athlete horses during training; the second technic presented, is the development of a prototype sensor with the same form of a horse shoe, encapsulated in a composite material reinforced with Carbon Fiber, this method was used in two horses during training as well. The first method allowed evaluate the behavior of the hoof in different phases of the horse gaits, such as walk and trot. The second technic, with the sensor element now encapsulated, allowed to evaluate different types of equine gaits, like walk, trot and run under training conditions. Both of the instrumentation using FGBs sensors technics were considered promising to clinical and biomechanics equine study in the medical evaluations or even during training or competition.

African horse sickness (AHS) is a viral disease with high mortality rates, vectored by the Culicoides midge and affecting members of the Equidae family. AHS is endemic to South Africa, and, as a result, affects export and international competitiveness in equine trade, and impacts significantly on the South African racehorse and performance horse industries. AHS also has devastating consequences for rural and subsistence equine ownership. The protocol developed in this dissertation has the potential to serotype and confirm the AHS virus within a few hours at significantly less cost than current methods. It will ease the financial and time constraints of studying an outbreak in real time and has the potential to solve many of the unknown factors surrounding AHS, particularly and most importantly, the role that each serotype plays in outbreaks and the form of the disease contracted by horses. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.