An arsenic-resistant Tick and its Control with Gammexane Dips

• DOI: 10.1017/s000748530002424x
• Publication Date: 2009-07-13T06:39:45Z
• Authors: A. B. M. Whitnall; B. Bradford
• Keywords: Strain (injury)

During the past 30 years, at least seven species of injurious insects are known to have evolved strains that more difficult kill with recognised chemical insecticides than normal populations these pests. In 1939 it was reported from East London area farmers were experiencing difficulty in controlling one host blue tick, B. decoloratus , by regular dipping 7-day strength arsenical wash. Field observations confirmed this. A technique for treating ticks laboratory is discussed detail. This has been put exhaustive test and some 15,000 adult female subjected vitro treatments remarkably consistent results. Experiments suggest arsenic kills contact. It further claimed using described possible furnish proof an arsenic-resistant strain does exist South Africa. would seem when once tick established itself on any farm, continued cattle washes results unintentional artificial selection those varieties within population resistant arsenic. Continued dippings thus aggravate position insecticide other should be used combat this . Gammexane experimented shown 0·005 per cent. sufficient females could taken as a basis experiments. Oil base preparations water suspensions twenty times toxic dust preparations.