Browsing by UP Author "Verwoerd, Daniel Wynand"

Browsing by UP Author "Verwoerd, Daniel Wynand"

Sort by: Order: Results:

  • Biography of Berend Cornelis (Ben) Jansen 
    Verwoerd, Daniel Wynand; South African Veterinary Association. History Committee (2011-01-11)
    Biography of the bacteriologist Ben Jansen (1921-1987). The biography includes information about his education and career, scientific contributions and writings, homages and distinctions.
  • Biography of Max Sterne 
    Verwoerd, Daniel Wynand; South African Veterinary Association. History Committee (2012-06-22)
    Biography of theveterinary bacteriologist and immunologist Max Sterne (1905-1997). The biography includes information about his education and career, scientific contributions and writings, homages and distinctions.
  • Biography of Petrus Johann du Toit 
    Verwoerd, Daniel Wynand; South African Veterinary Association. History Committee (2012-06-22)
    Biography of Petrus Johann du Toit (1888-1967). Dr du Toit contributed widely to the development of Veterinary Science, both on a national and international level, as a brilliant scientist, outstanding administrator, ...
  • Biography of Theunis Stephanus (Fanie) Kellerman 
    Verwoerd, Daniel Wynand; South African Veterinary Association. History Committee (2014-08-11)
    Biography of Fanie Kellerman. Kellerman was instrumental in the first diagnoses of many plant-induced toxicoses such as facial eczema, leucoencephalomalacia in horses and tremors in cattle caused by ryegrass or Aspergillus ...
  • Biotechnology, viral oncogenesis and jaagsiekte 
    Verwoerd, Daniel Wynand; Bigalke, R.D. (Published by The Government Printer, Pretoria, 1985)
    A brief description is given of the discovery of retroviral and cellular oncogenes and of their putative role in oncogenesis. Attempts to apply the biotechnological techniques that were so successful in the study of other ...
  • Demonstration of growth-inhibitory as well as growth-stimulatory factors in medium conditioned by lung lavage cells stimulated with a chemotactic factor secreted by jaagsiekte tumour cells 
    Verwoerd, Daniel Wynand; Myer, M.S.; Garnett, H.M.; Bigalke, R.D. (Published by the Government Printer, Pretoria., 1987)
    Both growth-inhibitory and growth-stimulatory factors were detected in vitro in medium from chemotactically stimulated cultures of lung lavage cells. The macrophage component of the lavage cells was found to produce a ...
  • The effect of a natural maedi-visna virus infection on the productivity of South African sheep 
    Bath, Gareth F.; Verwoerd, Daniel Wynand; Dungu, B.; Vorster, J.; Verwoerd, Daniel Wynand (Published by the Agricultural Research Council, Onderstepoort Veterinary Institute ., 2000)
    A cohort study was conducted in order to measure the effect of the chronic indurative lymphocytic mastitis caused by the South African strain of maedi visna virus (MVV) on the pre-weaning growth of lambs born ...
  • Experimental infection of vaccinated slaughter ostriches with virulent Newcastle disease virus 
    Verwoerd, Daniel Wynand; Gerdes, Gertruida Hermanna; Olivier, A.; Williams, R.; Verwoerd, Daniel Wynand (Published by the Agricultural Research Council, Onderstepoort Veterinary Institute, 1997)
    A virulent Newcastle disease virus (NDV) isolate from an outbreak in commercial poultry, with virulence indices of MDT = 47-48 h; IVPI = 2,17 and ICPI = 1,8; was used to inoculate 10x vaccinated (standard poultry vaccines) ...
  • Experimental transmission of jaagsiekte (ovine pulmonary adenomatosis) to goats 
    Verwoerd, Daniel Wynand; Tustin, R.C.; York, D.F; Williamson, Anna-Lise; Bigalke, R.D. (Published by the Government Printer, Pretoria., 1988)
    Jaagsiekte was successfully transmitted to at least 2 out of 6 goats inoculated intratracheally with partially purified jaagsiekte retrovirus. Multiple, small, well circumscribed nodules found in the lungs consisted of ...
  • Failure to demonstrate in vitro as opposed to in vivo transcription of the bluetongue virus genome 
    Verwoerd, Daniel Wynand; South Africa. Dept. of Agricultural Technical Services; Tustin, R.C.; De Lange, M.; Reinecke, R.K.; Walker, Jane B.; De Kock, V.E. (Pretoria : Government Printer, 1970)
  • History of bluetongue research at Onderstepoort 
    Verwoerd, Daniel Wynand (Agricultural Research Council, ARC-OVI and the University of Pretoria, 2009-03)
    Research on this economically important disease of ruminants, especially sheep, which had been named bluetongue by farmers in the 19th century, has been part and parcel of the activities at Onderstepoort ever since its ...
  • History of orbivirus research in South Africa 
    Verwoerd, Daniel Wynand (OpenJournals Publishing, 2012-11-13)
    In the early colonial history of South Africa, horses played an important role, both in general transportation and in military operations. Frequent epidemics of African horsesickness (AHS) in the 18th century therefore ...
  • Isolation and identification of a South African lentivirus from jaagsiekte lungs 
    Verwoerd, Daniel Wynand; Payne, Anna-Lise; York, D.F.; De Villiers, E.M.; Querat, G.; Barban, V.; Sauze, N.; Vigne, R.; Bigalke, R.D. (Published by the Government Printer, Pretoria., 1986)
    In the course of attempts to grow the jaagsiekte retrovirus in cell culture, a typical lentivirus was isolated for the first time in South Africa from adenomatous lungs. Morphologically the virus could not be distinguished ...
  • Isolation and preliminary characterization of the jaagsiekte retrovirus (JSRV) 
    Verwoerd, Daniel Wynand; Payne, Anna-Lise; York, D.F.; Myer, M.S.; Bigalke, R.D. (Published by The Government Printer, Pretoria, 1983)
    Jaagsiekte, or ovine pulmonary adenomatosis, is caused by a recently discovered retrovirus. The virus cannot be cultivated in vitro at present, but a procedure is described for the isolation and purification of small amounts ...
  • The localization of a Mason-Pfizer monkey virus-related antigen in jaagsiekte tumour tissue and cell lines 
    Verwoerd, Daniel Wynand; Payne, Anna-Lise; Garnett, H.M.; Bigalke, R.D. (Published by the Government Printer, Pretoria., 1986)
    Mason-Pfizer monkey virus-related antigen was detected in 3 out of 5 jaagsiekte lungs examined using a direct immunoperoxidase staining technique with anti-MPMV p27 serum. Most of the antigen was localized in the alveolar ...
  • The molecular revolution in biology and its influence on veterinary science 
    Verwoerd, Daniel Wynand (2007-10-15)
    Presentation and curriculum vitae of Dr D.W. Verwoerd. This Sir Arnold Theiler Memorial Lecture was delivered during Faculty Day, University of Pretoria, Faculty of Veterinary Science on the 29 September 2000 at Onderstepoort, ...
  • The morphology and morphogenesis of jaagsiekte retrovirus (JSRV) 
    Verwoerd, Daniel Wynand; Payne, Anna-Lise; Garnett, Helen M.; Bigalke, R.D. (Published by The Government Printer, Pretoria, 1983)
    Jaagsiekte retrovirus (JSRV) was recently shown to be the aetiological agent of jaagsiekte (ovine pulmonary adenomatosis). The morphogenesis of JSRV was studied in jaagsiekte tumour tissue. Intracytoplasmic particles, often ...
  • The possible involvement of immunosuppression caused by a lentivirus in the aetiology of jaagsiekte and pasteurellosis in sheep 
    Verwoerd, Daniel Wynand; Myer, M.S.; Huchzermeyer, Hildegard F.A.K.; York, D.F; Hunter, P.; Garnett, H.M.; Bigalke, R.D. (Published by the Government Printer, Pretoria., 1988)
    A South African isolate of ovine lentivirus was shown to cause a mild immunosuppression in sheep, reflected by a reduced delayed hypersensitivity reaction. This effect, measured in terms of skin swelling after intradermal ...
  • Production of a macrophage chemotactic factor by cultured jaagsiekte tumour cells 
    Verwoerd, Daniel Wynand; Myer, M.S.; Garnett, H.M.; Bigalke, R.D. (Published by the Government Printer, Pretoria., 1987)
    The increase of alveolar macrophages in jaagsiekte sheep lungs is not caused by excessive surfactant production but is due to a chemotactic factor secreted by the tumour cells. This factor has a molecular mass in the region ...
  • A scanning and transmission electron-microscopy study of jaagsiekte lesions 
    Verwoerd, Daniel Wynand; Payne, Anna-Lise; Bigalke, R.D. (Published by The Government Printer, Pretoria, 1984)
    A scanning electron microscopy (SEM) and transmission electron microscopy (TEM) study was made of lesions from acute, experimentally induced cases of jaagsiekte. In the SEM study tumour cells were easily identified by the ...