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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

Assessment of economic cost of human/elephant conflict in Tsavo conservation area, Kenya

Kaitopok, Jeremiah Poghon January 2015 (has links)
The aim of this study was to investigate the economics of damage to crops and infrastructure, injuries and loss of life at the human-elephant interface within Tsavo Conservation Area between 2010 and 2013. Data was generated from the Kenya Wildlife Service occurrence data base. A total of 488 cases with complete data were extracted. Both descriptive and inferential statistics was used in data analysis. The study established that zones with a higher incidence of conflict were proximate to the park and near main water points. Crop damage was the most (83%) prominent reason for human-elephant conflict. Others were property destruction (8%), human injuries (5%) and human deaths (4%). Crop damage occurred more often during wet seasons than dry seasons. Correlation analyses showed that the size of land was significantly associated with the value of the crop destroyed, with mean land size being 0.7 (+/- 0.99) acres. This was equivalent to 984,254 kg of crop yields over four years with an average of 246 063.71 (+/- 21 288) kg/annum. The main crop destroyed was maize, planted as a single crop. The majority (76%) of those affected were small holders with less than 0.7acres and they practiced subsistence farming. Men were the only gender killed by elephants (n=21), although both sexes were injured (n=24). In total, 40 incidents recorded damage to buildings and infrastructure. The value of crop damage, human injuries and deaths was Kenyan shillings 32,618,500 over the four year study period. It is recommended that the government should reduce human/elephant interaction in Tsavo Conservation Area by erecting an electric fence around the park, involving the community and compensating them for the entire cost of the loss incurred due to elephants from the Park. / Dissertation (MSc)--University of Pretoria, 2015. / tm2016 / Veterinary Tropical Diseases / MSc / Unrestricted
2

Prevalence of mastitogenic pathogens in pasture and total mixed ration based dairies during 2008 and 2013

Blignaut, David J.C. January 2015 (has links)
Mastitis is one of the most economically important diseases in dairy cattle worldwide. Not only does it have a negative effect on milk production, it also is one of the main reasons for culling dairy cattle. Pathogens causing mastitis in dairy cattle can be grouped into either contagious (or host adapted) or environmental pathogens. In different parts of the world it was shown that the prevalence of these differently grouped pathogens is dependent on various risk factors. Furthermore, it was shown that control measures implemented against contagious intramammary infections caused a relative shift over time towards a higher prevalence of environmental intramammary infections. In this study udder health data from the Onderstepoort Milk Laboratory (OML) was compared over two different years, 2008 and 2013, with regards to the prevalence of specified mastitogenic pathogens in total mixed ration (TMR) dairies and pasture-based dairies. Furthermore, the within-herd prevalence of Streptococcus uberis (Str. uberis) in Str. uberis positive herds was compared between the two years and the two management systems. Statistically significant differences were found in the prevalence of most of the major contagious and environmental mastitogenic pathogens between 2008 and 2013 and between the TMR and pasture-based dairies. Coagulase-negative staphylococci (CNS) has the highest prevalence in both TMR and pasture-based for both 2008 and 2013. Streptococcus uberis overall showed an increase in prevalence from 2008 to 2013, with the highest prevalence in pasture-based dairies in 2013. Staphylococcus aureus (S. aureus) showed a statistically significant decrease in TMR and pasture-based dairies from 2008 to 2013. The within-herd prevalence of Str. uberis increased from 2008 to 2013 with the highest within-herd prevalence in pasture-based dairies in 2013. / Dissertation (MMedVet)--University of Pretoria, 2015. / tm2016 / Production Animal Studies / MMedVet
3

A survey of farmers' experience using guard animals to control the impact of predators on farm livestock

Botha, Jolandie January 2018 (has links)
South African farmers have struggled for many years with the loss of livestock on their farms due to predators such as black backed jackals (Canis mesomelas) and caracal (Caracal caracal). These farmers have been known to use both lethal and non-lethal methods to control these predators on their properties. This study investigates the use of livestock guarding animals (LGAs) as a non-lethal method of controlling predators on farms. The study investigated the use of dogs, alpacas and donkeys on farms through the use of an online survey. Despite multiple appeals being sent out to different media outlets the response was modest. A structured, quantifiable and analysable questionnaire was sent to 34 farmers of whom 31 farmers completed the entire survey. The survey was used to gather information regarding the success of using these LGAs as well as the factors leading to their success and failure. There were 23 respondents who made use of dogs, eight who made use of alpacas and three using donkeys. Many studies have been done in the past on the use of dogs to protect livestock, these studies were done in Europe, the United states of America, Australia and Southern Africa. The use of both donkeys and alpacas have not been studied to the same degree. The hypothesis was that the use of LGAs (dogs, alpacas and donkeys), was successful in reducing predation by 50% or more on 75% or more of the farms surveyed. It was found that 21 of the 31 farmers who completed the survey said that predation decreased by 50% or more after acquiring a LGA. The factors leading to the success or failure in using these animals was determined for dogs, alpacas and donkeys individually. The questionnaire was designed to gather information about the farms such their size, terrain, the proximity to other farms, towns and nature reserves, and the wildlife found on the farm. We then looked at what livestock were being farmed and what LGA is being used by the farmer and how many of them are being used with the livestock. The questionnaire then went on to collect information on conception rates, lambing percentages, weaning percentages and percentages of livestock lost due to disease, predation and other factors. Looking specifically at predation we wanted to find out how much predation the farmers would attribute to which predator, how they determined which predator was responsible and how the predation changed over the time they had been using the LGA. It was also important to determine what methods of lethal control had been used previously on the farm and what was still being used by the farmers. Finally, the questionnaire covered the factors that contribute to the success and failure of the LGA as well as the cost of keeping the LGA. It was found that 33 of the 34 farmers had both sheep and cattle on their farms and only 11 farmed with goats. Nineteen of the farmers were farming on flat open plains. The farms were mostly in close proximity to other small livestock farms while others were on communal land. The number of LGAs used by the farmers were mostly determined by the size of the farm and the number of livestock. Supervision with livestock was not used by many farmers; 56% said it was unnecessary while 26% always had supervision with their animals. The rest of the farmers only occasionally had supervision with their animals. It was also found that the number of farmers making use of lethal control methods on their farms decreased from 80.65% before acquiring a LGA to 64.52% after acquiring a LGA. Predation was attributed to jackals on all farms, to caracal on 28 of the 31 farms of respondents that chose to answer this question, three farmers had problems with dogs and one farmer had predation due to leopards on his property. It was found that LGA had the greatest potential to decrease predation by jackals. The factors that were important for the use of dogs were their management, training and feeding. It was also found that dogs had the greatest financial impact on farmers as they cost more to acquire and maintain. The mean annual running cost as given by farmers was R11970.05. It was also seen that they had the greatest impact in reducing predation. The mean change in predation was 64% when making use of dogs. It was also seen that the weaning percentage on these farms increased by 25.23%. There was a change seen in the conception rate as well as the lambing percentage but neither was as large as with the weaning percentage. This is consistent with the fact that more lambs would survive if a LGA is keeping predators away. The factors that were listed as the most important factors in the use of alpacas were their temperament, the number of livestock you place with the alpaca and the age of the alpaca. The information collected on alpacas was small but showed that only four of the eight respondents saw an improvement on their properties after acquiring their alpaca. The cost of using an alpaca was not as significant as for dogs as they do not require extra housing or feed. The average running cost per annum for the use of alpacas was given as R525. There was no significant change in the conception rate, lambing percentage or weaning percentage of farmers making use of alpacas. There were only three responses for farmers making use of donkeys therefore there is no clear trend in the data but it has been reported on. The factors that were given as important were the gender of the donkey, specifically jennies (females) being more suitable, the donkey’s temperament, management and the number of livestock placed with the donkey. This was all in line with what was found in previous studies done on donkeys. Two of the three farmers using donkeys said that there was a 50% or more improvement in predation reduction on their farms. The average running cost of using a donkey was R2560 per annum. From the study it can be seen that these LGAs are successful in reducing predation but that more can still be done to encourage the use of alpacas and donkeys and to determine how successful they are. / Dissertation (MSc)--University of Pretoria, 2018. / Production Animal Studies / MSc / Unrestricted
4

Health assessment of tilapia (Oreochromis spp.) aquaculture systems in the northern provinces of South Africa

Taylor, Gillian Denise January 2019 (has links)
This study evaluated eighteen commercial farms within Gauteng, Northwest and Limpopo provinces, where a representative sample of grow-out fish from each farm, was humanely euthanased, weighed, measured, and each fish’s overall health assessed through microscopic examination of skin and gills. A full necropsy and histo-pathological evaluation of all key organs followed. Farm production parameters were assessed by means of a questionnaire with a detailed history and a comprehensive water analysis that included water temperature, dissolved oxygen, CO2, ammonia, nitrite, nitrate, pH, hardness and alkalinity. These production parameters, together with stocking density and underlying nutrition, were compared with the macro- and microscopic findings for positive and negative correlations / relationships. Significantly high burdens of ecto-parasites and very poor water quality, with compromisingly low dissolved oxygen and temperatures, and high carbon dioxide and nitrite, were found in association with severe gill pathology. This was compounded by inadequate filtration for the density of fish stocked, with resultant toxic nitrogenous waste accumulation. Other key abnormalities observed were chronic-active hepatic lipid oxidation, low hepatocellular lipid, evidence of secondary opportunistic infectious disease, and extremely poor growth. Poor farm management practises were prevalent, with evidence of uneconomical fish sex ratios, and poor implementation of biosecurity and disease management. The study serves to highlight the factors that currently dominate as critical issues affecting overall health and growth of aqua-cultured tilapia in the South African context. / Dissertation (MSc)--University of Pretoria, 2019. / TM2019 / Paraclinical Sciences / MSc / Unrestricted
5

Implementation of non-geographic approaches to beef trade in the SADC region

Palime, Mosiuoa Zachariah January 2015 (has links)
Access to international and regional markets for beef has been an on-going problem for southern African countries for many decades because the South African Territories (SAT) serotypes of foot and mouth disease (FMD) viruses are endemic to wildlife populations in the southern African region. This makes establishment of FMD-free zones, essential for accessing high-value beef markets difficult, expensive and impractical for many locations in southern Africa. For that reason commercialization of livestock production in the region has been inhibited. The creation of FMD-free zones which requires use of artificial or natural boundaries and in southern Africa it has been the construction of veterinary cordon fences (VCFs) to separate animal populations of different FMD status which has proven successful in some countries (such as Botswana, Namibia & South Africa) but not in others for a variety of reasons, i.e. the current model has only been possible for a small proportion of cattle producers in southern Africa. This means that apart from the damaging effects that some VCFs have had or have on the environment generally and wildlife conservation in particular, only roughly 15% of the cattle population in the mainland countries of the Southern African Development Community (SADC) are raised in FMD-free zones. For balanced rural development of the SADC Region, where cattle are culturally and economically vital to the indigenous inhabitants and wildlife conservation and associated economic activities are important contributors to regional gross domestic product, it is essential to improve access to regional and international markets for beef and other animal products produced in locations outside FMD-free zones. The World Organisation for Animal Health (OIE) has introduced a partially non-geographic FMD standard for trade in deboned beef (viz. Terrestrial Animal Health Code Article 8.8.22) that potentially overcomes this problem; however, Article 8.8.22 contains at least one killer requirement that makes its implementation impossible. The issues associated with this problem have been identified in this study and possible solutions proposed. An attempt was made to gauge acceptance by SADC Member States but the responses to the questionnaire used were inadequate to reach a reliable conclusion in this respect. It was concluded that taking technical, logistical and financial constraints into account, non-geographic approaches represent the best opportunity that SADC countries have of expanding access to regional and international markets. Moreover, it is suggested that non-geographic approaches could be integrated into the Standard Methods and Procedures in Animal Health (SMP-AH) Programme once adopted by SADC, thereby strengthening the capacity of the Region s competent authorities. SMP-AH Programme is at a proposal stage and has not been officially launched in SADC. The SMP AH Programme proposes to harmonize activities of animal health authorities of SADC Member States in respect of selected diseases that impact trade and/or human health. / Dissertation (MSc)--University of Pretoria, 2015. / tm2016 / Veterinary Tropical Diseases / MSc
6

Spatio-temporal analysis of dog ecology and rabies epidemiology at a wildlife interface in the Lowveld Region of South Africa

Grover, Michael January 2015 (has links)
It is estimated that free-roaming dogs comprise on average 75% of dog populations. Interactions between free-roaming dogs and wildlife occur across the globe but little is known about these interactions in the Lowveld region of South Africa, where wildlife areas are fenced off from surrounding communities. Even with extensive fences dogs are still entering the reserves. The study site, a private reserve in eastern Mpumalanga Province on the western boundary of the Greater Limpopo Transfrontier Park, has a high density of human settlements on its boundary. These communities own dogs, many of which are free-roaming. Between January 2009 and March 2014, 170 stray dogs were destroyed inside the reserve and 65.3% of the samples returned a positive result for rabies. Dogs are not limited to the reserve edges and have been documented several kilometres into the reserve. Eleven geographical factors were used in the spatial analysis: (i) camps or lodges in the reserve, (ii) fence line of the reserve, (iii) water points within the reserve, both natural and man-made (excluding rivers but including pans, dams and waterholes which hold water for most of the year), (iv) access roads from gates to camps and lodges, (v) access gates into the reserve, (vi) pickets (field ranger accommodation) and general staff accommodation, (vii) rivers in stream order from 1 to 6, (viii) vulnerable points for erosion along the fence line, and (ix) villages bordering the reserve. GPS locations of dogs shot were used to obtain nearest distance to each factor. Generalized linear models (GLM) were then used to analyse the spatial data of distance of dogs shot to the nearest factor. Dogs were significantly more likely to be shot further away from pickets and closer to minor rivers. There was a significant interaction between these two factors (p < 0.0001). Dogs that were shot further from villages (odds ratio 1.42, 95% confidence intervals 1.18 1.71, p = 0.0002) and closer to water (odds ratio 0.41, 95% confidence intervals 0.21 0.81, p = 0.009) were more likely to test positive for rabies. A univariate GLM, with distance to fence as the only explanatory variable, showed a significant association between this and rabies test result: for every 1 km further away from the fence the odds of a dog testing rabies positive increases by 1.68 (95% confidence intervals 1.20 2.36, p = 0.002). However the fence is likely not to be the influencing factor but rather other factors close to the fence. To remove the effect of the fence an analysis of the subset of dogs found further than 200m into the reserve found a positive association between distance from a village and a positive rabies test result (odds ratio 1.58, 95% confidence intervals 1.18-2.32, p = 0.007). Temporal analysis of the data shows a higher average monthly number of dogs shot during the wet season (Oct-Mar) as well as a higher variance although the cycle is not strictly seasonal. An upgrade of the reserve fence for security reasons coincided with a decrease in number of dogs destroyed in the reserve in 2012-1014. Home range analysis of most susceptible predators was collected from daily sightings data and overlaid with rabies hotspots, which gives management an indication of the need to vaccinate predators with home ranges in close proximity to the fence. The spatial results gives management an indication to increase efforts to destroy free-roaming domestic dogs further into the reserve as the likelihood of a positive rabies result is greater. Ultimately efforts should be focused outside the reserve in the communities to eradicate rabies from the host (domestic dogs) before there is a significant transfer of rabies to wildlife. / Dissertation (MSc)--University of Pretoria, 2015. / tm2016 / Veterinary Tropical Diseases / MSc
7

Acaricide resistance in Rhipicephalus (Boophilus) species at a communal dipping system in the Mnisi community Mpumalanga Province

Malan, Ros Catherine January 2015 (has links)
A study was conducted (November 2012) on the communal dipping system in Mnisi, Mpumalanga Province of South Africa to detect levels of blue tick resistance to commonly used acaricides. The larvae obtained from engorged females of the one host tick Rhipicephalus (B). microplus from twelve communal dipping areas were tested against various concentrations of amitraz, chlorfenvinphos and cypermethrin using the Shaw Larval Immersion Test method. Only R. (B). microplus ticks were identified from all sample areas, indicating a displacement of the indigenous R. (B). decoloratus tick in this area. Resistance testing using the Shaw Larval Immersion Test showed that no resistance to chlorfenvinphos was detected at any of the dip tanks, which was in keeping with the absence of known use of this product in the area. An important finding was the rapid development of resistance to the pyrethroids, which had only been in use for four months prior to conducting the study. Only one area (Hlalakane) yielded a R(B).spp population that was wholly susceptible to all three compounds. Resistance to amitraz was variable, with half (six out of 12) of the dip tanks comprising susceptible R(B).spp populations and two dip tanks with emerging resistance to amitraz. Possible risk factors which caused the resistance problems are discussed and acaricide management strategies recommended. / Dissertation (MSc)--University of Pretoria, 2015. / tm2016 / Veterinary Tropical Diseases / MSc
8

Diagnosis of tick-borne diseases in cattle in Bushbuckridge Mpumalanga South Africa and identification of Theileria parva carriers

Choopa, Chimvwele Namantala January 2015 (has links)
The Mnisi community is in the north-eastern corner of the Bushbuckridge Municipal Area, Mpumalanga Province, South Africa. This community is located at the livestock/wildlife interface sharing borders with several game reserves, and livestock are likely to be exposed to diseases with a wildlife reservoir, such as Corridor disease. Known tick vectors of important diseases such as Corridor disease, redwater, heartwater and anaplasmosis are present in the area. Although the farmers frequently dip their cattle in acaricide-filled dip tanks to control the tick burden, tick-borne diseases (TBDs) are still a major problem. This study was undertaken to determine if the symptoms of cattle in poor health in the Mnisi community could be attributed to TBDs. Corridor disease has previously been identified in cattle in the Mnisi community. Recent experimental studies have shown that T. parva DNA can be detected in infected cattle that survive the disease in the field. An additional aim of the study was therefore to identify T. parva carrier cattle in the area, and to search for evidence of selection of cattle-adapted T. parva parasites in carrier cattle. The study was conducted from July 2012 to June 2013. During the study period, samples from clinically sick cattle suspected of TBDs were collected to determine the cause of their symptoms. Blood smears from the clinically sick cattle were analysed using light microscopy while some cases were subjected to histopathology and T. parva-specific quantitative real-time polymerase chain reaction (qPCR). DNA extracted from blood samples and in some cases tissue samples collected from clinically sick cattle (n=137) was tested for the presence of haemoparasite DNA using the reverse line blot (RLB) hybridization assay. To identify T. parva carrier cattle, records from Hluvukani Animal Clinic and Bushbuckridge State Veterinary office were scrutinized to identify herds that may have been exposed to T. parva infection. Blood samples (n=670) were collected from herds that had recorded Corridor disease cases in the past three years, as well as herds that may have shared grazing with buffalo from the Kruger National Park and surrounding private game reserves. The indirect fluorescent antibody test (IFAT) was used to check for T. parva antibodies. Seropositive herds were revisited, as well as herds that had confirmed Corridor disease cases during the study period, and blood samples were collected (n=432). DNA extracted from these samples was screened for the presence of T. parva DNA using the T. parva-specific qPCR. In an attempt to find evidence of selection of cattle-adapted T. parva, the p67, p104 and PIM parasite genes were amplified from qPCR positive samples, and the amplicons were cloned and sequenced. Out of the 137 clinical disease cases examined from the study area, 24 cases of TBDs were diagnosed, of which 19 were Theileria related. The RLB hybridization assay confirmed the presence of tick-borne haemoparasites in the Mnisi community: 89 of the 137 clinical disease cases (65.0%) were found positive for one or more haemoparasite (Theileria, Babesia, Anaplasma and/or Ehrlichia species) while 48 (35.0%) were negative or below the detectable limit of the test. IFAT results indicated that there is a high seroprevalence of theileriosis (63.6%) in the Mnisi community area, but this may be due to cross reactions with other Theileria parasites known to be present (e.g. T. taurotragi). Fewer cattle (13.4%) were seropositive at the highest titre tested (160), and these are most likely to be associated with T. parva. In DNA extracted from blood samples from these seropositive herds, the T. parva-specific qPCR detected T. parva in eleven samples (2.6%). Eight of the eleven cattle were re-sampled six months later, but only one was still qPCR positive. All of the p104 and PIM sequences and two of the three p67 sequences were characteristic of buffalo-type T. parva alleles previously identified, implying that the T. parva infections in the cattle were transmitted directly from buffalo to cattle, and providing no evidence of selection of cattle-type alleles in the carrier animals. The study revealed that TBDs are a problem in the Mnisi community and surrounding area. Most important of the TBDs identified was Corridor disease, a notifiable disease in South Africa, which was the cause of most deaths among the cattle that were sampled. There was no evidence for the selection of cattle-derived T. parva alleles in any of the samples from T. parva carrier cattle, but a p67 sequence obtained from a clinical case was closely related to previously-identified alleles from cattle-derived isolates. Theileria parva DNA could only be detected in carrier cattle for a limited time post-exposure, suggesting that the infection will be cleared in infected animals before larvae or nymphs are available to pick up infections the following season. However, one bovine was still qPCR positive six months post-exposure, albeit with a very high Cp value (indicating a very low parasitaemia). The selection of T. parva parasites in cattle from the diverse T. parva population in African buffalo, therefore, remains a concern in the Mnisi community area, and at other livestock/wildlife interfaces in South Africa, but the risk is probably very low. / Dissertation (MSc)--University of Pretoria, 2015. / tm2016 / Veterinary Tropical Diseases / MSc
9

Development and efficacy testing of plant-produced virus-like particle vaccines against H6 avian influenza virus in chickens

Smith, Tanja January 2020 (has links)
The South African poultry industry has been beset by sporadic H6N2 avian influenza infection (sub-lineage I and II) in chickens since the early 2000s, with economic losses resulting from reduced egg production and co-infection with other pathogens. An egg-based inactivated H6N2 vaccine (AVIVAC® AI; Deltamune (Pty) Ltd.) based on a 2002 sub-lineage I isolate is available, although substantial antigenic drift has occurred in H6N2 viruses since its implementation. Globally, seasonal and pandemic plant-produced hemagglutinin (HA)- based influenza virus-like particle (VLP) vaccines are in advanced clinical trials with proven efficacy, speed of production, cost-effectiveness, scalability and safety, although not yet established for poultry. In this study, H6 avian influenza VLPs (sub-lineage I and II, respectively) were transiently produced in Nicotiana benthamiana and tested for protective efficacy in the target host. A production platform has been established for H6 VLPs in N. benthamiana by optimising protein expression and purification to maximize yield and by assessing the feasibility of large-scale production and downstream processing in a preliminary study. Subsequently, the respective plant-produced H6 VLPs were formulated into vaccines and their capacity to reduce viral replication and shedding upon challenge with a 2016 H6N2 field isolate were established in specific-pathogen-free (SPF) chickens, in comparison to the commercial H6N2 vaccine. The plant-produced sub-lineage I VLP vaccine (768 HA units/dose) was highly immunogenic (mean hemagglutination inhibition (HI) titer 10.7 log2), reduced the oropharyngeal and cloacal viral shedding by more than 100- and 6-fold, respectively, and shortened the duration of oropharyngeal shedding by at least a week in comparison to the non-vaccinated control. Due to initial low yield of sub-lineage II VLPs, the maximum antigenic mass vaccine dose (48 HA units/dose)) resulted in substantially lower HA-specific antibody titers (mean HI titer > 4 log2), but still reduced viral shedding from the oropharynx by more than 5-fold in comparison to the non-vaccinated control. In contrast, the commercial vaccine not only failed to effectively reduce shedding in comparison to the non-vaccinated control, but exacerbated oropharyngeal shedding until day 21 after viral challenge, illustrating the antigenic dissimilarity between the commercial vaccine and a recent field virus. Plant-produced VLP vaccines, which facilitates differentiation between infected and vaccination animals (DIVA), presents a new generation of poultry vaccines that is highly efficacious and cost-effective with the major advantage of producing a tailored antigenically-matched vaccine candidate within a short space of time and holds enormous potential for the poultry industry. / Thesis (PhD)--University of Pretoria, 2020. / Production Animal Studies / PhD / Unrestricted
10

Seroprevalence and factors associated with Q fever and Rift Valley fever in goats in Moretele municipality, South Africa

Magadu, Rungano January 2019 (has links)
Q fever is a zoonotic disease caused by Coxiella burnetii which infects humans and a wide range of hosts including birds, mammals, ticks, fish and reptiles. Rift Valley fever (RVF) virus (RVFV) is a mosquito-borne pathogen of livestock, wildlife and humans and is found throughout much of sub-Saharan Africa, occasionally causing large scale abortions and mortality. There is little detailed knowledge of the distribution and level of occurrence of these two pathogens in South Africa. The aim of this study was to estimate the prevalence of antibodies against C. burnetii and RVFV in goats in Moretele municipality, and to identify factors associated with seropositivity to the two zoonotic pathogens. Multi-stage random sampling was conducted and sera were collected from 216 goats in 32 goat herds. A questionnaire was completed for each participating goat owner to collect information on potential animal, management and environmental risk factors, as well as potential animal health consequences of the two infections. Rift Valley fever virus antibody testing was done by ID Screen® Rift Valley Fever Competition ELISA test kit (IDVet, Grabels, France) and C. burnetii antibody testing was done by LSIVETTM Ruminant Q Fever - Serum/Milk ELISA test kit (Life Technologies, Carlsbad, California, USA) with confirmation using a virus neutralisation test (VNT). 32/216 goats tested positive for C. burnetii antibodies and the overall seroprevalence, adjusted for clustering and sampling weights was 16% (95% CI: 10.6-23.5%). The intraclass correlation co-efficient (ICC) was 0.06, indicating low to moderate clustering within herds. Multiple logistic regression revealed age as the only factor that was significantly associated with seropositivity to C. burnetii, with a higher seroprevalence in animals ≥2 years of age (26%) than in animals ≤6 months of age (6%) (odds ratio (OR) = 6.6; 95% CI: 1.6-26.7; P = 0.010). Regarding potential consequences of infection, females with a history of abortion were more likely to be seropositive (OR = 4.6; 95% CI: 1.1-20.2; P = 0.043). Goats in herds that reported >2 abortions in the 12 months prior to sampling tended to have a higher odds of seropositivity than animals in herds with no reported abortions (OR = 2.5; 95% CI: 0.9-6.8; P = 0.071). 1/216 goats tested ELISA-positive for RVF virus antibodies and 3 samples were “doubtful”; however, they all tested VNT-negative. The estimated seroprevalence of RVFV was therefore 0% (95% CI: 0.0-1.4%). In this study, the herd seroprevalence of C. burnetii was high at 51% and there was possibility that C. burnetii is a likely cause of abortions in goats in Moretele municipality of South Africa. Seropositivity to RVFV could not be demonstrated in this study; but if present, the virus is likely to be circulating at very low levels. / Dissertation (MMedVet)--University of Pretoria, 2019. / Production Animal Studies / MMedVet / Unrestricted

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