Departmental Activities. 109 



The House Ant. — Experiments on the control of the common and 

 \"ery troublesome lioiise ant, Pheidole panctulata, are being carried 

 out by the Natal Entomologist at Durban. Sodium cyanide appears 

 to be giving" very favourable results, bat because of the extremely 

 dangerous nature of this poison it is not at present recommended as a 

 control measure. Sodium arsenite, sodium hyposulphite (hypo.), and 

 vaporite were alsj tried, but so far the results with these are not 

 encouraging. 



VETERINARY EDUCATION AND RESEARCH. 



Investigations into Nagana in Zululand. — Mr. H. H. Cuison, 

 Veterinary Research Officer, in this Division, was sent to Zululand 

 in April, 1921, to investigate Nagana in cattle and other domestic 

 animals. A short summary of his work during the ensuing year is 

 given below, divided into three periods of four months each: — 



Preliminary Inquiries. — May, 1921 — August, 1921. — As the 



site selected for the Nagana Research Laborator;^^ — Farm No. 273 in 

 the Ntambanana Settlement, about 15 miles from Empangeni — was 

 quite undevoloped, it was expected that buildings would be con- 

 structed, fences erected, and a bore-hole sunk during this period. 

 Since, however, there were delays, I considered it would be an advan- 

 tage to take a trip through the northern districts of the country, 

 where Nagana has been a scourge for generations, and to make obser- 

 vations with regard to the history, geographicnl distribution and topo- 

 graphy of the disease ; and to note the association between the geo- 

 logy, zoology, and botany of the country, and the ])revalence of 

 Nagana. An opportunity was also taken at the same time to make 

 inquiries into a disease of cattle along ihe coastal belt of Inarwavuma 

 and TJbombo Districts. It was held by some that the malady was 

 identical with Nao^ana, but as no veterinarian had visited the area, 

 the matter required investigation, especially as the mortality had been 

 severe in 1917, 1919, and 1920. (3n examination of diseased animals, 

 all evidence pointed to the affection — known locally as "Swamp 

 Disease" or " Munca " — being a parasitic gastro-enteriris, and 

 worms sent to the Director of Veterinary Education and Research 

 were later identified as Haemonchvs contnrtus (wireworm) and two 

 less common species, Cooperia punctata and Cooperia pectinata. 



As a result of my trip I came to the following conclusions: — 

 Conditions under which Swamp Disease and Nagana Occur. — 

 (1) The coastal belt is characterized by sandveld (except in the vicin- 

 ity of rivers), which supT)orts a vegetation giving but little sbade, 

 e.g. palms and grasses. This area has a warm and humid climate, is 

 exceedingly swampy, more so as one approaches the sea, and is a 

 hotbed of parasitic infection. In such places, sheep and goats cannot 

 live and cattle in some seasons die to the extent of 25 per cent. 

 Further west, however, between the Mbaswana and Mosi Swamps, 

 where the country is well drained, cattle thrive, and in the middle of 

 winter are fat and sleek, whereas at the same time of the year in 

 Natal, Karroo, Free State, or Transvaal Highveld, animals are in 

 poor condition, being walking skeletons. 



