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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.
171

An assessment of the effectiveness of trade union participation in municipal decision-making: a case study of the Buffalo City Municipality

Apraku, Amos January 2010 (has links)
The objectives of this study were to first identify the decision-making bodies structures in the Buffalo City Municipality. Secondly, to assess compositions, powers and functions of such identified bodies or structures. The field study was limited to the administrative jurisdictions of the Buffalo City Municipality; however, the findings and recommendations were applicable to all municipalities in South Africa with the same or similar decision-making like the Buffalo City Municipality. In order to achieve the research objectives, a review of the relevant literature was done. It began by first looking at the constitutional and other legislative provisions establishing the Municipal government system or concept. The literature review looked at the powers and functions given to municipal governments by such constitutional provisions and how effective are such powers exercised. The literature further highlighted the role of trade unions participation and civil society groups in the smooth and effective administration of the municipality and in making the Integrated Development Planning a successful one. The data collection was done by means of questionnaire, focus group discussions complimented by face-to-face interviews. Forty respondents were sampled from six different trade unions and top municipal management. The data collected were analysed thematically with the use of frequency tables, pie charts and histograms. The findings of the study showed among other things that, the highest decision-making body in the municipality is the municipal council supported by various committees, boards and directorates. All the legislative and executive powers are vested in the municipal council. Again, it became known that, the municipal workers unions participate effectively in labour related issues whereas the non-municipal workers unions participate poorly in all consultative processes. In conclusion, there is the urgent need to bring all stakeholders including trade unions in the municipality during decision-making processes in order promote sustainable development in the municipality.
172

An analysis of the factors influencing the provision of water in the Buffalo City Municipality, province of the Eastern Cape

Zwelibanzi, Mantombi Elizabeth January 2011 (has links)
Factors affecting the provision of water constitute a great challenge to water officials not only in Buffalo City Municipality but also globally. Interviews form the basic data collection instrument used to provide empirical evidence to the objectives of the study. The objectives of the study are: To evaluate the underlying challenges encountered by water sector Engineers; To evaluate the role of municipal water sector officials in the provision of clean water; To analyse the factors influencing the provision of water in Buffllo City Municipality. Recommendations are provided which could assist Buffalo City Municipality in addressing the challenges affecting the provision of water as follows: The involvement of national and provincial governments in order to improve the Buffalo City Municipal infrastructure and capacity building is highly recommended. Power failure and water interruptions caused by mechanical problems and natural disasters, are further municipal challenges that need to be addressed irrespective of financial constraints. Public and private sector sponsors can be approached to join the initiative. Informal settlements should be formalised and limited to a certain number of people per site or household, depending on the infrastructure. If the infrastructure is not conducive they should be relocated elsewhere. Public and private sector sponsors should offer assistance to Buffalo City Municipality to develop the required water skills, by financing water officials who are interested in furthering their education at tertiary level. Public consultation, through meetings and public forums, and public participation, by the street committees and police forums, are recommended. Coupon systems for basic services like water and electricity for all residents is highly recommended. A generator for the municipal water sector is needed. This will overcome the power failure problem. The provision of water is affected by power outages as water equipment needs electricity to be able to operate. Installation of a water plant in Buffalo City Municipality‟s main dam, the Maden dam, that is supposed to supply King Williams town and the surrounding areas directly.
173

Assessing the 'breaking new ground in housing' policy of South Africa in meeting the objectives of community participation

April, Tandeka January 2011 (has links)
Community participation is an important aspect of South African government policies that deal with integrated development planning and sustainable development. This report presents aspects of community participation in infrastructure delivery and in particular housing in Reeston which is part of the Duncan Village Redevelopment Initiative in East London area of the Buffalo City Metropolitan Municipality. The importance of community participation is acknowledged as it enhances the ability of the community members to demonstrate and use their own views to deal with specific issues and to address the needs and problems that emerge and prevail in their societies. The two emerging paradigms of community participation suggest that the participating communities should be involved in the ‘selection, design, planning and implementation’ of projects that will have an effect on them and from which they are going to benefit ; and that continuous feedback to communities forms a fundamental part of any development activity. This report explores how the “Breaking New Ground in Housing” (BNG) policy of the South African Government meets its objectives in the context of community participation.
174

Estudo da influência da adição de lecitina de soja na molhabilidade do leite de búfala em pó obtido por spray-drying

Hammes, Martim Victor January 2013 (has links)
Existe atualmente uma crescente produção de leite de búfala no Brasil e no mundo, sendo que 13% do leite mundial é produzido por esta espécie, perdendo somente para a produção do leite bovino. Esse crescimento deve-se às características peculiares do leite desta espécie em comparação ao bovino, incluindo teores mais elevados de vitamina C, minerais (como cálcio e fósforo), gordura e proteína. Uma alternativa para dar maior rentabilidade econômica ao leite consiste na transformação do produto para a forma de pó de fácil reconstituição (instantâneo) através de um processo de secagem. Como a reconstituição de um alimento em pó depende significativamente das suas características de molhabilidade, é comum a utilização de processos como aglomeração e lecitinação para melhorar a molhabilidade do leite em pó. Neste contexto, o objetivo deste estudo consiste em investigar a influência da adição de lecitina, antes da secagem por atomização, na molhabilidade do leite de búfala em pó. Com esta finalidade, o leite de búfala in natura foi semidesnatado, pasteurizado, concentrado a 40% (percentual mássico) de sólidos totais e seco por pulverização. Nos produtos preparados com lecitina, este aditivo foi utilizado em proporções de 0,3, 0,5 e 1,0 g de lecitina/100 g de sólidos totais no leite concentrado, previamente ao processo de secagem por atomização. Nestas condições, o efeito da concentração de lecitina na molhabilidade do leite em pó produzido foi avaliado através da técnica de Washburn e do teste de molhamento estático. Ainda, o material seco foi avaliado quanto ao teor de umidade, distribuição de tamanho de partículas e, para amostras específicas, quanto à área superficial, atividade de água, cor e morfologia das partículas (via microscopia eletrônica de varredura). Foi observado que a adição de lecitina diminuiu o tempo de molhamento (valores compreendidos entre 63,9 e 188,4 s) quando comparado ao leite in natura (300,9 s). O ângulo de contato das amostras de leite em pó obtidas em níveis superiores a 0,3% de lecitina adicionada diminuiu significativamente, para valores compreendidos entre 82,73 ± 2,76° e 81,21 ± 2,23°, com relação ao valor obtido sem adição do aditivo (89,01 ± 0,48°). Entretanto, a presença de lecitina não apresentou considerável influência na umidade, atividade de água, cor, morfologia, área superficial e na distribuição de tamanho das partículas obtidas. / There is nowadays a growing production of buffalo milk in Brazil and in the world. It already represents 13% of total world milk production, being second only to the production of bovine milk. This growth is due to the peculiar characteristics of this kind of milk compared to cow milk, such as higher content of vitamin C, minerals (such as calcium and phosphorous), fat and protein. An alternative to provide greater economic return from milk consists in converting the product to powder for easy reconstitution (i.e. instant food) through a drying process. As the reconstitution of a powdered food depends strongly on its characteristics of wettability, the utilization of alternatives such as agglomeration and addition of lecithin are commonly used to improve the wettability of the final product. In this context, the aim of this study is to investigate the influence of the addition of lecithin, previously to the spray drying on the wettability of buffalo milk powder. For such purpose, the fresh buffalo milk was partially-skimmed, pasteurized, concentrated to 40% (mass percent) of total solids and spray-dried. Four milk powders were produced, one without addition of lecithin and three with different contents of lecithin (0.3, 0.5 and 1.0 g of lecithin/100 g of total solids). The effect of the concentration of lecithin on the wettability of the powder produced was measured by the Washburn technique and static wetting test. Further, the dried material was analyzed for moisture content, particle size distribution, and for specific samples, for surface area, water activity, color and particle morphology (scanning electron microscopy). It was observed that the addition of lecithin decreased the wetting time (values comprised between 63.9 and 188.4 s) when compared to lecithin-free milk (300.9 s). The contact angle of the milk powder samples obtained with levels greater than 0.3% of added lecithin significantly decreased to values between 82.73 ± 2.76° and 81.21 ± 2.23°, with respect to the value obtained without addition of the additive (89.1°). However, the presence of lecithin showed no significant influence on the moisture content, water activity, color, morphology, surface area and particle size distribution of the produced powders.
175

Bone density and calcium and phosphorus content of the giraffe (Giraffa camelopardalis) and African buffalo (Syncerus caffer) skeletons

Van Schalkwyk, Ockert Louis 20 October 2004 (has links)
Apart from its slender appearance, four main factors lead to questions regarding the bone density, mineral content and morphology of the giraffe skeleton: X A rapid vertical growth rate ¡V especially in the neck and metapodials X Biomechanical considerations pertaining to the tall and slender shape of the skeleton X A proportionally larger skeleton in relation to body mass X A seemingly abnormal mineral balance in their diet with possible signs of mineral deficiency (i.e. osteophagia) In this study the skeleton of the giraffe was compared with that of the African buffalo with regards to bone density, skeletal calcium (Ca) and phosphorus (P) content and certain femoral and metacarpal morphological characteristics. The aim was to establish if, compared to buffalo, the features of the giraffe skeleton differed in any unique way. Fourteen similar bones or parts of bones were collected from carcasses of six adult giraffe bulls and nine adult buffalo bulls. These bones were cleaned, weighed and their volume determined through water displacement, from which their density could be calculated. Hereafter, Ca and P content were analysed in 10 bones from each carcass. Morphological characteristics of cross-sections from femoral and metacarpal shafts were also measured. No significant differences between the density or mineral content of bones in the two species could be found. In both species 19,5% Ca and 9,5% P were measured in defatted bone. Although similar in mineral concentration, the giraffe skeleton contains three times more absolute Ca and P, which translates into a 1,5-2-fold higher dietary requirement for these minerals compared to buffaloes. A gradation in the volume and weight of cervical vertebrae was also seen in giraffes. This could hold biomechanical advantage for the carriage and manoeuvrability of the long neck. Bone wall thickness of the giraffe femur and metacarpus is increased compared to buffaloes. This could hold biomechanical advantage for the slender legs that are subjected to increased vertical forces. Adequate Ca seems to be acquired through very specific browse selection, which seems to be of evolutionary origin, while the acquisition of adequate P seems to be critical and a possible cause for osteophagia. This study is the first of its kind in these species and therefore also provide valuable baseline data for future work in this field. / Dissertation (MSc (Veterinary Science))--University of Pretoria, 2004. / Production Animal Studies / unrestricted
176

An immunohistochemical and histological evaluation of the African buffalo (Syncerus caffer) retina

Odayar, Lo-An January 2013 (has links)
Vision studies and visual acuity investigations are an ongoing and progressive field in veterinary ophthalmology. These independent studies all help to contribute to a combined and collective knowledge in our understanding of this truly complex matter. Understanding retinal morphology and physiology is an integral factor in piecing together overall function of the eye. Many of these studies have been done in both medical and veterinary ophthalmology using behavioural factors, electrophysiology, special staining and scanning techniques on a histological level. In the veterinary field many species have been studied pointing out similarities or differences among them. This study hopes to contribute to the understanding of the retinal ultrastructure of the African buffalo (Syncerus caffer). Twenty-five pairs of African buffalo eyes were obtained, but only forty-eight eyes were included in this investigation. The globes of one donor appeared to have chronic intraocular disease and were phthisical. Since this is a descriptive study of normal anatomy and function, these eyes were excluded. Globe dimensions were recorded and statistically analysed, revealing an average horizontal diameter of 32.91mm and a vertical diameter of 33.04mm. The median age of the donor group was 4 years with Using scanning electron microscopy it was established that African buffalo retinas, like other domestic species, have a specialised region a few millimetres dorsolateral to the optic disc, synonymous to the well described area centralis. In this region a higher concentration of cones is found as opposed to other rod-rich regions. In a concurrent investigation, the contralateral globes were processed for immunohistochemical antibody staining. Colour specific anti-bodies were used to identify the cone population present in the African buffalo retina. The conclusion of this investigation reveals that this species like other domestic animals has dichromatic colour vision, recognising short and medium to long colour wavelengths. / Dissertation (MMedVet)--University of Pretoria, 2013. / gm2014 / Companion Animal Clinical Studies / unrestricted
177

Occurrence of Anaplasma and Ehrlichia species in African buffalo (Syncerus caffer) in Kruger National Park and Hluhluwe-iMfolozi Park in South Africa

Debeila, Elizabeth Matshidiso 29 May 2013 (has links)
Theileriosis, babesiosis, heartwater and anaplasmosis are considered to be amongst the most important tick-borne diseases of livestock in sub-Saharan Africa‟s tropical and subtropical regions resulting in extensive economic losses to farmers in endemic areas. It is well-known that the African buffalo (Syncerus caffer) is the natural reservoir host of various tick-borne haemoparasites of veterinary importance. In this study, the occurrence of tick-borne haemoprotozoan parasites (Theileria, Babesia, Anaplasma and Ehrlichia species) in buffalo from two geographically isolated national parks in South Africa (Kruger National Park and Hluhluwe-iMfolozi Park) was determined using the reverse line blot (RLB) hybridization assay. The RLB results revealed the presence of Theileria, Babesia and Anaplasma species either as single or as mixed infections. Although not detected with the RLB assay, 5% of the buffalo blood samples from the KNP tested positive for the presence of Ehrlichia ruminantium using the pCS20 real-time PCR assay. Previous studies on the occurrence of haemoparasites in the South African buffalo population have mainly focussed on the prevalence of Theileria species only. The finding on the presence of Anaplasma, Ehrlichia and Babesia species is therefore a novel contribution. This study has confirmed the findings of previous studies that buffalo is the natural reservoir host of both pathogenic and non-pathogenic Theileria species namely, T. parva, Theileria sp. (buffalo), T. mutans, T. velifera and T. buffe1i.In this study, the most frequently occurring Theileria species detected in the KNP were T. mutans (81%), Theileria sp. (sable) (61%), T. parva (40%), Theileria sp. (buffalo) (13%) and T. velifera (11%). Theileria buffeli was not detected in the KNP. In the Hluhluwe-iMfolozi Park, the most occurring Theileria species were T. mutans (55%), T. velifera (54%), T. parva (53%), Theileria sp. (sable) (53%), Theileria sp. (buffalo) (49%) and T. buffeli, (49%). Theileria sp. (sable) causes fatal clinical disease in roan and sable antelope in South Africa and we can only speculate whether the presence of Theileria sp. (sable) DNA in the buffalo population was a true and/or incidental finding. An interesting finding was the presence of Babesia occultans DNA in 50% of the buffalo from the Hluhluwe-iMfolozi Park. Babesia occultans is the causative agent of a benign form of cattle babesiosis in South Africa and, to date; this organism has not been identified in wildlife in South Africa. The significance of this finding warrents further investigation and confirmation using gene cloning, sequencing and phylogenetic analysis. Ehrlichia ruminantium has been reported to infect not only domesticated ruminants but also wild ruminants, however most wildlife species appear to carry the organism asymptomatically. In this study, we were not able to detect E. ruminantium DNA in any of the buffalo samples tested using the RLB hybridization assay. However, using the quantitative pCS20 real-time PCR assay we detected E. ruminantium DNA in 5% of the KNP samples. None of the Hluhluwe-iMfolozi Park samples tested positive for E. ruminantium using the real-time PCR assay. These results suggest that buffalo is not the natural reservoir host of E. ruminantium. However, a subclinical carrier state in buffalo has been experimentally shown to occur after tick transmission from carrier animals and further studies will have to be conducted to confirm whether this finding holds any potential risk to domestic animals. In Southern Africa, two Anaplasma species are known to infect cattle, A. marginale and A. centrale. Clinical bovine anaplasmosis is usually caused by A. marginale; whilst A. centrale generally results in mild disease. Because there is partial cross immunity between the two species, A. centrale is used as a live vaccine for cattle in Israel, South Africa, South America and Australia. Apart from cattle, Anaplasma marginale has been described in wild ruminants which can become persistently infected serving as reservoirs for infection of susceptible hosts; it has been recovered from 10 wild ruminants. Subclinical occurrence of A. marginale, either natural or after artificial infection has been confirmed in the African buffalo and various other wildlife species. In this study, the Anaplasma species detected from HluhluweiMfolozi Park buffalo samples were A. centrale (75%), A. marginale (42%) and Anaplasma (formerly Ehrlichia) sp. Omatjenne (28%). DNA of these species was also detected in buffalo from KNP; A. centrale (49%), A. marginale (24%) and Anaplasma (Ehrlichia) sp. Omatjenne (5%). The presence of A. marginale in the buffalo population suggests that buffalo may be a factor in the epidemiology and spread of bovine anaplasmosis because, as reservoir hosts of A. marginale, they could serve as a source of infective blood for mechanical spread by various routes and biological transmission by ticks. Factors such as climate, host abundance, tick host diversity, and topography have, however, all been shown to also impact on the epidemiology of A. marginale. Subsequently 64 samples were selected that either tested (i) positive for a specific Anaplasma spp. (A. centrale, A. marginale and/or Anaplasma (Ehrlichia) sp. Omatjenne) using the RLB assay, or (ii) in which the PCR products hybridized only with the Anaplasma/Ehrlichia genus-specific probes for molecular characterization by cloning and sequencing of the 16S rRNA gene. Aplification of the full-length and/or partial parasite 16S rRNA gene of any of the selected samples that previously tested positive for the presence of Anaplasma (Ehrlichia)sp. Omatjenne (using the RLB assay) or E. ruminantium (using the pCS20 real-time PCR assay) was unsuccessful. This was most probably due to low rickettsaemia. However, amplification of either the near full-length parasite 16S rRNA gene or a partial 16S rRNA gene from seven samples from the KNP and three from Hluhluwe-iMfolozi Park was successful. Results indicated that the obtained sequences of 12 of the 18 clones were highly similar to published A. centrale 16S rRNA gene sequences, four of the clones were highly similar to the published A. marginale sequences and the sequences of the remaining two clones were closely similar to Anaplasma (Ehrlichia) sp. strain Omatjenne. The observed sequence similarities were confirmed by phylogenetic analyses. An interesting finding was the presence of one full-length parasite 16S rDNA sequence that was 100% identical to that of the published A. centrale vaccine strain sequences. It is well known that A. centrale is widely used as live vaccine for the control of bovine anaplasmosis. The occurrence of A. centrale vaccine strain DNA in the South African buffalo population is therefore of great interest. It can only be speculated whether A. centrale has evolved in the African buffalo, and/or if buffalo act as natural reservoir hosts, or if is it merely being maintained in the buffalo population by in utero transmission. This also serves as the first report of Anaplasma (Ehrlichia) sp. Omatjenne DNA in the African buffalo which warrents further investigation. In conclusion, the findings suggest that buffalo is a natural reservoir of Anaplasma spp. infection and could play an important role in the epidemiology and spread of anaplasmosis and may represent a serious threat to the livestock industry. / Dissertation (MSc)--University of Pretoria, 2012. / Veterinary Tropical Diseases / unrestricted
178

The osteology of the cranial and facial bones of the savannah buffalo Syncerus caffer caffer (Sparrman, 1779)

Hornsveld, Marius 08 December 2009 (has links)
Zoologists classify the savannah buffalo under the Bovini Tribe. Osteologically, the skull differs from that of the water buffalo of Asia, inter alia, in that the vomer does not articulate with the palatine part of the osseus palate. This gross anatomical study gives a detailed description of all the bones of the skull, mandible and hyoid apparatus of the savannah buffalo Syncerus caffer caffer (Sparrman, 1779). These bones are similar in many respects to that of the domestic bovine. However, due to the robustness of the buffalo skull, many aspects pertaining to bones or parts of bones that are different or more pronounced, are of anatomical importance. The sum-total effect of all these features, gives the skull its typical macro-morphology that differentiates it clearly from the other genera in the Bovini Tribe. The more important characteristics that were found, are the following: 1. The skull of young animals retains basic embryonic reshaping potential till quite late in life. It can be seen as a remnant of Meckel's cartilage in the mandible as well as in prolonged remodelling in the regions of the orbit, dorsum of the nose, and most markedly, also in the lateral walls of the cranium. A subsequent temporary atypical fontanel can even leave an osseus scar in the temporal region. 2. Temporary canals, associated with the developing permanent premolars, appear in the maxilla and mandible. 3. A well defined biomechanical supporting pillar forms internally in the skull of the buffalo. It conveys pressure from the lingual side of the caudal molar alveoli, to the ipsilateral external lamina of the frontal bone in the region of the frontal fossa. 4. Apart from one small external segment, fusion of the perpendicular and basal plates of the ethmoid bone to the presphenoid bone, in the region of the orbital plate, makes ethmoid-related sutures the least visible sutures to see in all post-natal stages. 5. The retro-orbital position of the cornual process, and the presence of a nasoincisive suture, are some of the osteological features that are shared with the domestic goat. 6. Pneumatization of the nasal bone and dorsal concha may occur, as well as of the tympanic part of the temporal bone. 7. The detail of the sutures other than those of the ethmoid bone, may allow "fingerprint" identification of specific bones or complete skulls. Other applied aspects of the skull may be of importance to hunters and clinicians. / Thesis (PhD)--University of Pretoria, 2002. / Anatomy and Physiology / unrestricted
179

Aspects of the epidemiology of Theileria parva infections in cattle and African buffalo (Syncerus caffer) in South Africa revealed by tick transmission and sub-inoculation of blood

Stoltsz, Wilhelm Heinrich 24 May 2012 (has links)
The aim of this study was to investigate three key epidemiological aspects of Theileria parva infections in cattle and African buffalo (Syncerus caffer) in South Africa. The first of these was the possible behavioural change (i.e. transformation) of buffalo-derived T. parva (causing classical Corridor disease in cattle) to what might be considered cattle-derived T. parva (causing classical East Coast fever in cattle) after repeated tick-passage in cattle. For the first time a South African isolate of buffalo-derived T. parva was successfully transmitted using Rhipicephalus zambeziensis for eight passages in non-splenectomised cattle. This was achieved despite most animals developing fatal infections with extremely low piroplasm parasitaemias, and without chemotherapeutic intervention. This finding indicates that, contrary to earlier belief, Corridor disease is not a self-limiting disease in cattle, and given the opportunity, could well become established in a cattle population in the absence of buffalo. Despite repeated tick transmission in cattle of the South African buffalo isolate of T. parva used in this study, it did not exhibit the behavioural changes associated with “transformation” to typical cattle-derived T. parva. Secondly, the potential role of the common waterbuck (Kobus ellipsiprymnus) in the selection of cattle-adapted subpopulations of parasites from buffalo-derived T. parva was investigated. Waterbuck captured in Kruger National Park (KNP) were screened by conventional and molecular diagnostic techniques for Theileria spp. infections. Laboratory-reared R. zambeziensis were fed on captive buffalo confirmed to be naturally infected with T. parva. The ensuing adult ticks were fed on captive waterbuck and cattle. All the waterbuck were found to carry microscopically detectable Theileria sp. piroplasm infections, found by polymerase chain reaction (PCR) diagnosis to belong to a hitherto uncharacterised Theileria species. R. zambeziensis adults which fed as nymphs on the buffalo transmitted fatal T. parva infections to cattle. However, no transmission of T. parva to the waterbuck could be demonstrated clinically or by PCR diagnosis. Also, R. zambeziensis nymphs that were subsequently fed on the waterbuck failed to transmit T. parva to cattle in the ensuing adult stage, confirming the absence of T. parva-group infections in the waterbuck. The results suggest that buffalo in KNP probably do not carry T. parva-group parasites which are readily transmissible to common waterbuck and waterbuck are therefore unlikely to play an important role in the epidemiology of T. parva-group infections in cattle in South Africa. Thirdly, to investigate the carrier state of buffalo-derived T. parva infections in cattle, blood from infected non-splenectomised and splenectomised carrier cattle was subinoculated to splenectomised cattle. T. parva infections were successfully transmitted by subinoculation of 1000 ml of blood at various intervals after infection to splenectomised recipient cattle. Donor animals comprised of recovered intact cattle, reacting intact cattle or splenectomised recovered cattle. Microscopically detectable piroplasm parasitaemias were detected in all recipients after inoculation. One splenectomised recipient developed a moderate clinical reaction, accompanied by a moderate schizont parasitosis, but recovered spontaneously, confirming persistence of schizonts in some T. parva carrier animals. By contrast, a T. parva piroplasm infection, persisting in a treated recovered splenectomised bovine, in the apparent absence of circulating schizonts, was serially (consecutively) passaged in splenectomised cattle. Seroconversion occurred in all recipient cattle. With the exception of the recipient which developed a clinical reaction and circulating schizonts, none of the recipients showed any clinical signs of T. parva infection. Upon homologous sporozoite challenge with T. parva, two out of three recipient animals with only microscopically detectable piroplasm parasitaemias developed fatal T. parva infections and one recovered after exhibiting severe clinical signs. These findings confirm the stage-specific immunity in T. parva and, contrary to popular belief, the possibility of long-term maintenance of piroplasm parasitaemias in the absence of schizonts in carrier cattle. The technique of subinoculating and establishing virulent T. parva carrier infections in splenectomised cattle also provides a method whereby buffalo-derived parasite stocks may be isolated and maintained for characterisation and the preparation of sporozoite stabilates for inclusion in T. parva vaccines. Copyright / Dissertation (MSc)--University of Pretoria, 2011. / Veterinary Tropical Diseases / unrestricted
180

Studies on utilization of by-products for ruminant feeds in tropical Asia / 熱帯アジアにおける未利用資源の反芻家畜への飼料化に関する研究

Sakai, Takashi 23 March 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第20446号 / 農博第2231号 / 新制||農||1050(附属図書館) / 学位論文||H29||N5067(農学部図書室) / 京都大学大学院農学研究科応用生物科学専攻 / (主査)教授 廣岡 博之, 教授 松井 徹, 教授 久米 新一 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

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