Page 72 - VHSA - Onderstepoort 100 Years - Part 3

OND
ERSTEPOORT 100
– the first protozoan parasite to be cultured thus at Onderstepoort – which facilitated the development of a vaccine several years later.
The discovery of a Besnoitia spp. in blue
wildebeest in the Kruger National Park by
P.A. Basson, J.W. van Niekerk, McCully, and
Bigalke in 1965 paved the way to vaccine
development. A blue wildebeest strain was
isolated in cell culture by Bigalke and was
surprisingly shown to cause only a mild
reaction when injected into cattle, which
were then protected against infection with
the clinical form of the disease in the field.
This led to the development of a cell culture
vaccine containing the blue wildebeest strain in 1974. In these and later studies Bigalke was ably assisted by J.H. (Jan) Schoeman, a qualified technologist who later became a senior official in the Onderstepoort vaccine factory, now named Onderstepoort Biological Products.
Walters’ research on the protozoa of invertebrates known as microsporidia resulted in a dissertation for which he was awarded an MSc degree in 1962. He left Onderstepoort in 1971, was awarded a PhD in 1978, and became an Asso- ciate Professor of Biology at the Medical University of South Africa (Medunsa) in 1984.
By the time Neitz retired from Onderstepoort in 1971 at the age of 65, he had published 133 articles in various jour- nals, but mostly in the Onderstepoort Journal of Veterinary Research and its various predecessors such as the Report on Veterinary Research of the Union of South Africa in which some of his early articles appeared. In later years many of these articles were in the form of reviews often exceeding 100 pages.
162 A good example is his paper entitled: ‘Theileriosis, Gonde- riosis and Cytauxzoonosis. A review’, which was published in the Onderstepoort Journal of Veterinary Research, Vol. 27, pp. 275-430 in 1957. Another was: ‘African swine fever. A review’. FAO Agricultural Studies, Rome, No. 61, 1963, pp. 3-226.
Renewal and growth (1971-1991)
Bigalke became the second head of the Section of Protozoo- logy when he succeeded Neitz in 1971. His approach to its leadership was different in the sense that he tried to attract as many young researchers as possible. Although not yet head of the section at the time, he had canvassed A.J. (Albertus) de Vos to join in 1967 and F.T. (Fred) Potgieter arrived in 1972, shortly after Neitz’s retirement. De Vos had initially been instructed to conduct research on coccidiosis, which he did very success- fully by concentrating on coccidia of the indigenous rodents that he managed to trap on the Onderstepoort campus. In elegant experiments, which he conducted on SPF (coccidia- free) striped and multimammate mice bred in the laboratory for this purpose, he showed that the Eimeria spp. concerned were not very host-specific. This was a revolutionary finding because the eimerias are generally regarded as being very host-specific.
When Bigalke took over the section he tasked de Vos with the production of redwater/babesiosis vaccine with the objective of replacing the existing carrier-donor system, characterized by un- reliable infectivity, with one delivering a standardized product. He also encouraged de Vos to visit overseas babesiosis research experts in the USA and Australia to gain ex- perience in the most recent developments in the babesiosis and anaplasmosis fields. Such a visit was made possible when de Vos was awarded the much sought-after BP (South Africa) scholarship for 2 years’
study in 1970. De Vos made excellent progress with this research, the first of significance since the time of Theiler. By 1973 he had developed a standardized, chilled, combined vaccine from acutely infected, splenectomized calves contain- ing a standardized number of Babesia bigemina and Babesia bovis organisms per ml, using less pathogenic strains.
In the meantime Bigalke took on the responsibility for the production of anaplasmosis vaccine. He was not only concerned about poor infectivity of the vaccine – several reports of vaccine failures from very reliable sources had been received from the field – but in research conducted on the pathogenicity of the Anaplasma centrale vaccine strain he observed that the organism, although generally a mild pathogen, was much more pathogenic for adult cattle than had been anticipated. He changed the existing carrier-donor system to one in which use was only made of splenectomized
“The discovery of a Besnoitia sp. in blue wildebeest in the Kruger National Park by P.A. Basson, J. W. van Niekerk, McCully, and Bigalke in 1965 paved the way to vaccine development.”
A.J. de Vos (1974-1982) inter alia revolutionised the Onderstepoort redwater vaccine before emigrating to Australia
PART 3
History of Individual Disciplines
1908-2008
Years