This thesis showed that dogs with natural infection with B. canis had both renal and cardiac dysfunction, both of which can be classified as complications of babesiosis and would thus necessitate supportive therapy. This thesis demonstrated that RTE celluria, proteinuria, and variable enzymuria and azotaemia occur in dogs with babesiosis. However, these were all minimal changes and all could be consistent with hypoxia, reduced GFR, or reduced cardiac output This thesis showed that dogs with naturally occurring babesiosis had significant urine met-haemoglobin with no evidence of blood met-haemoglobin. The possibility would be that the urinary methaemoglobin was either produced in the kidney or possibly by oxidation of haemoglobin to met-haemoglobin in the bladder. It has been shown experimentally that met-haemoglobin can be toxic. The combination of reduced GFR, anaemic hypoxia, and met-haemoglobin can all act synergistically to cause renal damage. Renal haemodynamics are also much more likely to be abnormal when cardiac dysfunction is present Reduced renal blood flow and glomerular filtration rate are evidence of redistribution of blood flow that commonly occurs in early heart failure. An important finding in this thesis was that dogs with babesiosis had lower serum sodium than control dogs but there was no difference between mild, severe, or complicated cases of babesiosis. In addition, dogs with babesiosis had a lower fractional clearance of sodium than Clinically healthy control dogs, which can be interpreted as sodium retention by the kidneys. This sodium retention would also result in water retention , which will result in an expansion of the plasma volume. In the past heart lesions in canine babesiosis were regarded as rare complications, with the majority of lesions being reported as incidental findings at post-mortem examination of complicated babesiosis cases. This thesis has demonstrated that cardiac lesions to be common in canine babesiosis. This thesis showed that that ECG changes in babesiosis were similar to the pattern described for myocarditis and myocardial ischaemia, and together with the histopathological findings indicated that the heart suffers from the same pathological processes described in other organs in canine babesiosis, namely inflammation and hypoxia. As the clinical application of the ECG changes found in this thesis was limited, cardiovascular assessment should be based on functional monitoring rather than ECG. Using cardiac troponin as a marker of myocardial injury, this thesis showed that myocardial cell injury occurs with canine babesiosis. Cardiac troponins, especially troponin I, are sensitive markers of myocardial injury in canine babesiosis, and the magnitude of elevation of plasma troponin I concentrations appears to be proportional to the severity of the disease. ECG changes and serum cardiac troponin were correlated with histopathology. On cardiac histopathology from dogs that succumbed to babesiosis, haemorrhage, necrosis, inflammation and fibrin microthrombi in the myocardium were documented, all of which would have resulted in ECG changes and elevations in cardiac troponin. Myocardial infarction causes left ventricular failure, which will result in hypotension and an expansion of the plasma volume due to homeostatic mechanisms. This thesis showed that dogs with babesiosis had hypoalbuminaemia, which may be because of intravascular volume dilution due to fluid retention. In disease hypoalbuminaemia can occur as a negative acute-phase protein. In the light of the cardiac changes, hyponatraemia, and hypotension, a probable cause would be fluid retention due to myocardial disease. This thesis showed that dogs with babesiosis had left ventricular lesions, which can result in systolic heart failure. / Thesis (PhD)--University of Pretoria, 2005. / Veterinary Tropical Diseases / unrestricted

Brucellosis is one of the neglected diseases in Nigeria. In Lagos, the commercial capital of Nigeria with about twenty one million people, a descriptive cross-sectional study was carried out in order to determine the sero-prevalence of brucellosis among people at risk in some selected abattoirs and secondary health care facilities (hospitals) in the state. Mixed sampling method was employed at the abattoir while convenient sampling method was used in sampling the respondents at the hospitals. Sera samples from three hundred and one (n=301) abattoir-based workers and traders; and one hundred and twenty one (n=121) hospital-based individuals which include people with febrile illnesses and blood donors were tested for brucellosis using Rose Bengal Plate test (RBPT), with indirect ELISA being used as a confirmatory test. Of the 301 abattoir-based workers and traders, 27 (8.97%) were sero-positive to the infection when Rose Bengal Plate test antigen was used. The twenty seven individuals consists of fifteen (15) butchers; four (4) veterinarians; two (2) meat transporters and bone/cow horn dealers each as well as one each of blood meal producer, abattoir engineer, water seller and meat supplier. When blood samples from the sero-positive individuals were subjected to ELISA, 3 (11.1%) were sero-positive to the brucellosis, while one is equivocal. These results confirm that agglutination observed on RBPT might be related to unknown cross-reactions and confirmation with a different test was necessary. None of the hospital-based respondents is sero-positive to the infection. The clinical signs significant for the infection in this study were fever, joint pain, lower backache, regular headache and miscarriage. Brucellosis awareness level among the respondents was very low. Data was analysed using (SPSS) version 20.0 at α0.05 significant level. The significant risk factors for human brucellosis according to this research are consumption of fura (unpasteurized milk) and wara (fresh cheese). The study revealed that brucellosis is not only an occupational disease but can also affect people who trade or live in proximity with infected animals. / Agriculture, Animal Health and Human Ecology / M. Sc. (Agriculture)