Jaagsiekte is a contagious cancer affecting the lungs of sheep. Although the etiological agent is Jaagsiekte retrovirus (JSRV), two other retroviruses viz South African maedi visna virus ( SA - OMVV) and a novel Bovine retrovirus (BRV) have been associated with or implicated in the jaagsiekte disease complex. JSRV was sufficiently purified from lung rinse material using a Freon extraction, Percoll density gradient centrifugation and chranatography on a Sephacryl column, its polypeptide composition was studied by gel electrophoresis and its morphology observed electron microscopically. Monoclonal antibodies were made against purified preparations of the virus. Two hybridomas were isolated that produced MAbs which appear to be tumour cell specific. A third hybridoma, called 4A1O, produces antibodies considered to be viral specific. These MAbs have been used in the development of JS specific immunoassays. A cross reaction between JSRV and a polyclonal serum against Mason Pfizer monkey virus (MPMV) was confirmed and used in a Western blot technique to identify, monitor and differentiate JSRV from other viruses. During the study of JSRV it became apparent that another retrovirus was often present in JS infected lungs. This virus, referred to as SA - OM1V I, is a novel South African isolate of maedi visna virus (MVV). As SA - OM1V I has physicochemical characteristics similar to JSRV, it was often found in purified JSRV preparations. Being a retrovirus it is also detected by the reverse transcriptase assay which was the only method used to assay and monitor for JSRV during the early stages of our work. Using a Westen blot technique and sera against MVV and MPMV it was possible to simultaneously detect and differentiate JSRV from SA - OMVV I. A method was also developed whereby the two viruses could be separated from each other during purification. The information gained and techniques developed whilst studyiing JSRV were also used to isolate and characterize BRV. This novel virus originated from bovine cells that had been co-cultivated with white blood cells from an ox suffering from malignant catarrhal fever. Three out of four sheep inoculated with BRV developed JS. It therefore had to be· ascertained whether this virus was related to JSRV or not. The comparative study revealed that BRV was biochemically and morphologically quite different fran JSRV. Interestingly, it was shown that serum against MPMV cross reacted with a 32 kd protein of BRV indicating a serological relationship between JSRV, MPMV and BRV. The possible role of BRV in the etiology of jaagsiekte remains to be elucidated. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1987.

Several final sewage effluents from the Denton Disposal Plant were demonstrated to contain Poliovirus types II and III. Pleated encapsulated filters at pH3.5 enhanced the recovery of the Poliovirus at a higher tier in comparison with nitrocellulose filter (Millipore) and glass fiber filter of pore size 0.45u. This thesis explores problems that face us today in our quest to eliminate viral pathogens from the natural and waste water needed for human, domestic, and industrial consumption. Preliminary experiments concern the use of immunofluorescence, and immunodiffusion techniques as a means of poliovirus identification, which invariably suggests that these techniques may be useful as rapid screening procedures of water samples for presence of potentially pathogenic viruses.