Thoroughbred horse jump racing is popular in Great Britain (GB). Unfortunately it is associated with inherent risk of injury to the horses involved and it has been shown that the risk is significantly higher in jump than in flat racing. As a result, jump racing has been made a priority in racehorse injury investigation by the racing authorities in GB and is the focus of this thesis. Data about injuries and fatalities collected by veterinary surgeons, from all official race meetings between 2000 and 2009 was made available by the British Horseracing Authority (BHA). Following initial examination of the data, review of the literature and discussion with the BHA, a list of outcomes (injuries and fatality) was defined for further investigation. Multivariable logistic regression modelling was employed to investigate associations between potential risk factors and the outcomes. Model validation techniques were then used for outcomes with the greatest frequencies. In addition, post-mortem (PM) findings from a subset of the available data provided the opportunity to evaluate the accuracy of the information provided. Outcomes selected for further investigation were: fatality, tendon strain, epistaxis, hind limb fracture, pelvic fracture, and proximal forelimb fracture. Multiple risk factors were identified as being significantly associated with each outcome which can be used to guide legislation or further investigation. Risk factors common to many of the outcomes were: season, surface firmness (going), race distance and previous racing history (especially previous flat start history). Notably in some instances the relationships between these common risk factors and the outcomes varied, such that a risk factor might be associated with increased likelihood of one outcome but a decreased likelihood of another. Attempts to validate the models with the most frequent outcomes (fatality, superficial digital flexor tendinopathy and epistaxis) against a novel data set (from the year 2010), demonstrated variable calibration and discrimination and relatively poor predictive ability for all of the models. This was thought to be related to the low outcome frequencies and potentially related to risk factors unaccounted for in the models. Evaluation of the accuracy of the recording system for fatal distal limb fractures using PM findings demonstrated good identification of fracture presence, but relatively poor definition of all affected bones. Frustratingly it was concluded that making policy decisions based on the risk factor models will not be straightforward. Few risk factors had strong associations with all outcomes, not all risk factors are readily modifiable and many potential modifications (such as stopping horses from racing) would have major long term deleterious implications for horses. However, new risk factors for injury were identified providing some additional information about injury aetiology; previously recognised associations (such as firm ground and injury) are supported by the work; and sensible recommendations can be made to the industry, such as: closer monitoring of horses based on their previous racing careers or previous injuries. In addition, further training of racecourse veterinarians and/or provision of diagnostic aids (such as radiography) can be recommended to help with diagnoses made at the racecourses.

The principal aims of the work presented in this thesis were to further investigate the pathophysiology of the acute phase proteins in bovine mastitis and to document the changes in the protein composition of milk during mastitis using modem proteomic methods. Mastitis is one of the most important diseases affecting cattle worldwide. It has adverse effects on the economics of milk production through reducing the quality and quantity of milk. Acute phase proteins (APPs) are valuable markers of inflammatory lesions and are widely used in the veterinary field for disease diagnosis. This study further investigated the presence of APPs, haptoglobin (Hp) 1 I and mammary- associated serum amyloid A3 (M-SAA3) in the milk of cows with mastitis and evaluated the possibility of using these proteins to detect mastitis. An Enzyme linked immunosorbent assay (ELISA) was developed and validated for the measurement of milk Hp. A commercially available ELISA was used for the detection ofM-SAA3 in milk. Both Hp and M-SAA3 showed similar kinetics to somatic cell counts and can be considered as sensitive and reliable markers of mastitis. Advanced proteomic methods were developed and used to further characterise the changes taking place in the proteins expressed in normal and mastitic milk. The methodology for analysis of the bovine milk proteome was successfully established. This part of the work concluded that the patterns of protein expression of clinically mastitic milk showed clear differences from that of normal milk. Further analysis of milk samples from a mild subclinical model of Staphylococcus aureus mastitis showed that alterations to the milk p:oteome were only minimal. However this study was useful in identifying areas worthy of future research. Recent publications on APP research speculate upon the local production ofM-SAA3 in the bovine mammary gland. The final objective of this study was therefore to investigate the expression of MSAA3 in bovine mammary tissue. Our studies confirm the local production of M-SAA3 in the bovine mammary gland and its up-regulation during bovine mastitis. This finding may provide further information on a possible role for this protein. Overall the findings detailed in this thesis indicate that APPs in milk are valuable markers of mastitis and additionally that the ease of collection of milk by non-invasive methods suggest that milk has potential for the discovery of disease biomarkers.

This thesis examines some aspects of milk yield manipulation utilizing some factors that can effect the function of the mammary gland. In the first part of study, the effect of photoperiod on lactation performance in the goats was studied, and particularly to investigate if this response can be potentiated by prior exposure to short periods of short days elicited by melatonin treatment. Long light did not produce clear stimulatory effect on milk yield, but a small response was seen in autumn and only in goats that were not treated by melatonin. Repeated short cycles of melatonin did not sensitize lactating goats to subsequent long light effect to milk yield regardless of stage of lactation or commencement time of year. Indeed, this treatment might produce a detrimental effect on milk yield when applied in early lactation. The second part of the study was to determine the maximum metabolic capacity of cows from different genetic merit. We adopted a multiple galactopoietic stimuli, increasing milking frequency, bovine somatotropin and thyroxine, applied in additive stepwise fashion at peak yield to cows from high and low genetic merit. This approach was successfully drove the cows into what we believe their maximum metabolic capacity. Milk yield was increased in an additive fashion at each stimulus. The increase in milk yield capacity was associated with mammary growth which was detected during the maximum stimuli. There was no significant difference in the response to the galactopoietic stimuli between cows from different genetic merit which did not suggest that high genetic merit cows are milking closer to their maximum capacity and, therefore, at greater risk of collapse of metabolic control than low genetic merit cows.

A longitudinal epidemiological study of trypanosome infections in domestic livestock was carried out over thirteen months in Busia District, an endemic area of Rhodesian sleeping sickness. It was demonstrated that chemoprophylaxis of domestic livestock with Samorin ® (Rhône Poulenc, France) could virtually eliminate the reservoir of potentially human infective T. brucei spp. infections in domestic animals. In addition to being a potentially useful control measure during outbreaks of sleeping sickness, chemoprophylaxis showed a net economic benefit in the productivity of local cattle. The duration of chemoprophylaxis of domestic livestock with Ethidium ® (Laprovet, France) was much less, as was the economic benefit to livestock production, however the level of challenge was much less in this trial. From the relative preference of tsetse flies for each species of domestic animal and the prevalence and incidence of trypanosome infections, it was concluded that cattle and to a lesser extent pigs were the most important species of domestic livestock in the animal reservoir of Rhodesian sleeping sickness in Busia District. Of the risk factors investigated for cattle acquiring trypanosome infections, the most important was an existing trypanosome infection. The effect on the epidemiology of sleeping sickness of a greater than expected interaction between species of trypanosome infecting cattle offers a possible mechanism for the natural control of the animal reservoir of Rhodesian sleeping sickness. Various parasitological diagnostic techniques for the detection of trypanosome infections in cattle in the field were assessed. Maximum sensitivity of diagnosis and minimum bias in the relative importance of each species of trypanosome was achieved by selecting a suitable combination of diagnostic techniques.

"Major Subject: Veterinary Medicine" Title from author supplied metadata (automated record created 2010-03-12 12:08:51). Includes bibliographical references.

Thesis (MSc (Paravet. Studies))--University of Pretoria, 2004. / Includes bibliographical references.

Thesis (M.S.)--Texas A & M University, 2003. / "Major Subject: Veterinary Medicine and Surgery." Title from author supplied metadata (record created on Jul. 18, 2005.). Vita. Abstract. Includes bibliographical references.

Thesis (Ph. D.)--Washington State University, May 2006. / Includes bibliographical references.

Foot-and-mouth disease (FMD), a disease of cloven hooved animals caused by FMD virus (FMDV), is one of the most economically devastating diseases of livestock worldwide. The global burden of disease is borne largely by livestock-keepers in areas of Africa and Asia where the disease is endemic and where many people rely on livestock for their livelihoods and food-security. Yet, there are many gaps in our knowledge of the drivers of FMDV circulation in these settings. In East Africa, FMD epidemiology is complicated by the circulation of multiple FMDV serotypes (distinct antigenic variants) and by the presence of large populations of susceptible wildlife and domestic livestock. The African buffalo (Syncerus caffer) is the only wildlife species with consistent evidence of high levels of FMDV infection, and East Africa contains the largest population of this species globally. To inform FMD control in this region, key questions relate to heterogeneities in FMD prevalence and impacts in different livestock management systems and to the role of wildlife as a potential source of FMDV for livestock. To develop FMD control strategies and make best use of vaccine control options, serotype-specific patterns of circulation need to be characterised. In this study, the impacts and epidemiology of FMD were investigated across a range of traditional livestock-keeping systems in northern Tanzania, including pastoralist, agro-pastoralist and rural smallholder systems. Data were generated through field studies and laboratory analyses between 2010 and 2015. The study involved analysis of existing household survey data and generated serological data from cross-sectional livestock and buffalo samples and longitudinal cattle samples. Serological analyses included non-structural protein ELISAs, serotype-specific solid-phase competitive ELISAs, with optimisation to detect East African FMDV variants, and virus neutralisation testing. Risk factors for FMDV infection and outbreaks were investigated through analysis of cross-sectional serological data in conjunction with a case-control outbreak analysis. A novel Bayesian modeling approach was developed to infer serotype-specific infection history from serological data, and combined with virus isolation data from FMD outbreaks to characterise temporal and spatial patterns of serotype-specific infection. A high seroprevalence of FMD was detected in both northern Tanzanian livestock (69%, [66.5 - 71.4%] in cattle and 48.5%, [45.7-51.3%] in small ruminants) and in buffalo (80.9%, [74.7-86.1%]). Four different serotypes of FMDV (A, O, SAT1 and SAT2) were isolated from livestock. Up to three outbreaks per year were reported by households and active surveillance highlighted up to four serial outbreaks in the same herds within three years. Agro-pastoral and pastoral livestock keepers reported more frequent FMD outbreaks compared to smallholders. Households in all three management systems reported that FMD outbreaks caused significant impacts on milk production and sales, and on animals’ draught power, hence on crop production, with implications for food security and livelihoods. Risk factor analyses showed that older livestock were more likely to be seropositive for FMD (Odds Ratio [OR] 1.4 [1.4-1.5] per extra year) and that cattle (OR 3.3 [2.7-4.0]) were more likely than sheep and goats to be seropositive. Livestock managed by agro-pastoralists (OR 8.1 [2.8-23.6]) or pastoralists (OR 7.1 [2.9-17.6]) were more likely to be seropositive compared to those managed by smallholders. Larger herds (OR: 1.02 [1.01-1.03] per extra bovine) and those that recently acquired new livestock (OR: 5.57 [1.01 – 30.91]) had increased odds of suffering an FMD outbreak. Measures of potential contact with buffalo or with other FMD susceptible wildlife did not increase the likelihood of FMD in livestock in either the cross-sectional serological analysis or case-control outbreak analysis. The Bayesian model was validated to correctly infer from ELISA data the most recent serotype to infect cattle. Consistent with the lack of risk factors related to wildlife contact, temporal and spatial patterns of exposure to specific FMDV serotypes were not tightly linked in cattle and buffalo. In cattle, four serial waves of different FMDV serotypes that swept through southern Kenyan and northern Tanzanian livestock populations over a four-year period dominated infection patterns. In contrast, only two serotypes (SAT1 and SAT2) dominated in buffalo populations. Key conclusions are that FMD has a substantial impact in traditional livestock systems in East Africa. Wildlife does not currently appear to act as an important source of FMDV for East African livestock, and control efforts in the region should initially focus on livestock management and vaccination strategies. A novel modeling approach greatly facilitated the interpretation of serological data and may be a potent epidemiological tool in the African setting. There was a clear temporal pattern of FMDV antigenic dominance across northern Tanzania and southern Kenya. Longer-term research to investigate whether serotype-specific FMDV sweeps are truly predictable, and to shed light on FMD post-infection immunity in animals exposed to serial FMD infections is warranted.

The PARABAN project has been a Scotland-wide initiative to develop and deliver farm-specific ‘best practice’ for the control of Mycobacterium avium ssp. paratuberculosis (MAP) in cattle using ‘Knowledge Exchange’. A range of partners have been involved, including nine ‘Champion Farms’. With input from the farmer, his/her vet and PARABAN advisors, a tailored monitoring and control programme was devised for each ‘Champion Farm’, taking into account the history of the disease on the farm, the physical facilities available and farmer objectives. Culling decisions based on live animal test results were incorporated into each farm-specific programme to complement the management programme already in place to maintain each herd. Results were analysed and discussed with all the partners throughout the project and then offered for wider scrutiny at farm open days. Feedback and questions from these open days have been used to complete the ‘Knowledge Exchange’ cycle. As a major component of the PARABAN project the author collected samples from all adult animals culled from ‘Champion Farms’ at slaughter or as fallen stock, irrespective of in-life MAP test status. These were then subjected to histopathological examination by experienced veterinary pathologists and the results compared with the results from in-life MAP testing. This was intended to evaluate the contribution slaughterhouse sampling could make towards decision making for disease control on farm and formed the main aim of this thesis. In total, samples of terminal ileum and draining lymph node were collected from three-hundred and fifty-two animals. A positive result on histopathology was defined as the presence of lesions typical of MAP and also the presence of acid-fast bacteria within the sections. There was found to be fair agreement between the overall results from histopathology and serum ELISA (Kappa = 0.33), though there appeared to be some variation in agreement between the tests on the individual ‘Champion Farms’. The presence of MAP was confirmed in seven of the eight farms which contributed animals to this study, despite sometimes prolonged efforts at controlling the disease. A separate study was undertaken to make use of the archives of the Scottish Centre for Production Animal Health and Food Safety at the Veterinary School, University of Glasgow. The archive contained records of cases from across southern Scotland and northern England. Analysis of the data generated from examination of these records suggested that MAP is widespread within the Scottish cattle herd and may well be increasing.