Page 34 - VHSA - Onderstepoort 100 Years - Part 3

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ERSTEPOORT 100
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R.M. du Toit, Head of the Section of Entomology, with the light trap used to collect Culicoides midges from which bluetongue and African horsesickness viruses were isolated for the first time
with his own meticulous drawings and covering the fields of both Entomology and Helminthology, was the standard textbook for veterinary students for decades. It survives to this day, now edited by Lord Soulsby. Although Mönnig will be remembered chiefly for his studies on helminths he also worked on ectoparasites, and had a sound knowledge of their taxonomy as evidenced by the excellence of his own illustrations in his book. He lectured to the veterinary students in the disciplines of both entomology and helminthology.
After David Bruce’s discovery in 1895 that a trypanosome was the causative organism of nagana in cattle in Zululand
and that tsetse flies (Glossina spp.) were the biological vectors, there were various attempts at eradicating the flies from the region. R.H.T.P. Harris studied the ecology of the flies, and devised his famous trap. Wildlife was shot on a large scale, but to no avail.
R.M. (René) du Toit qualified as a veternarian in 1927 and immediately joined the government service. He was sent to the Allerton Laboratory outside Pietermaritzburg for a year, but was transferred to the Section of Entomology at the Insti- tute in 1929, where, but for a short period on the Depart- ment of Agriculture’s experimental farm at Armoedsvlakte and studying at the University of Minnesota, he spent the remainder of his career. He conducted pioneering research on the application of DDT for the control of ectoparasites between 1939 and 1945. During this time he planned the successful campaign of aerial spraying with DDT to eradicate Glossina pallidipes, the most important vector species of tsetse fly in north-eastern KwaZulu-Natal.
Du Toit was awarded a DVSc degree for his treatise on this eradication campaign. In 1944 he discovered that the viruses that caused African horsesickness and bluetongue in sheep were transmitted biologically by Culicoides spp. After Mönnig’s resignation he presented the lectures in Entomology at the Faculty, and was also Dean of the Faculty from 1960 to 1963.
Sir Arnold’s younger daughter, Gertrud, a biologist by training, returned to South Africa in 1924 after obtaining a doctoral degree from the University of Neuchâtel in
Tsetse fly, vector of nagana in cattle, was controlled more successfully in South Africa than in any other African country (drawing by A. Olwage)
PART 3
History of Individual Disciplines
1908-2008
Years