Alexander, R.A.Neitz, W.O.Du Toit, P.J.2017-04-182017-04-1820171935Alexander, RA & Neitz, WO 1935, 'The transmission of louping ill by ticks (Rhipicephalus appendiculatus)’. Onderstepoort Journal of Veterinary Science and Animal Industry, vol. 5, no. 1, pp. 15-33.0330-2465http://hdl.handle.net/2263/59924The articles have been scanned in colour with a HP Scanjet 5590;300dpi. adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.1. Experiments conducted to demonstrate the susceptibility of horses and cattle are described. 2. The appearance of virucidal antibodies in the serum of these animals after infection is demonstrated by a technique of in vitro neutralization of virus. 3. The technique of tick feeding investigations is briefly described. 4. It is shown that- (a) larvae of R. appendiculatus will pick up infection for transmission as nymphae; (b) nymphae will pick up infection for transmission as adults; (c) the virus does not pass through the egg to the next generation; (d) infective nymphae tend to lose their infection after feeding on immune animals though some of the resulting adults may still be infective ; (e) the same occurrence was noted after feeding infective nymphae on susceptible animals but, particularly if sheep are the hosts, there is a danger of the nymphae reacquiring infection before detachment; (f) clean ticks do not acquire infection when feeding on an immune animal simultaneously with infective ticks. 5. The significance of the work is discussed.en©South Africa, Dept. of Agricultural Technical Services (original). ©University of Pretoria, Dept. of Library Services (digital).Veterinary medicineVeterinary medicine -- South AfricaArticle