Horn Fly Control—Using Spray, Dust, and Pour-On Formulations1

Abstract

Results of horn fly Haematobia irritans (L.)) control on cattle after using sprays, dusts and pour-on applications were observed during 1960 and 1961. Pour-on applications of Co-ral® (O,O-diethyl O-3-chloro-4-methyl-2-oxo-2 H -1-benzopyran-7-yl phosphorothioate), and Ruelene® (O-4- tert -butyl-2-chlorophenyl O -methyl methylphosphoramidate) 0.5% and Dylox® ( O,O dimethyl 2,2,2-trichloro-1-hydroxyethyl propionate) 1% gave excellent horn fly control for 14 days and good control for 28 days. Dust applications of Diazinon® ( O ,-diethyl O-(2-iso propyl-4-methyl-6-pyrimidinyl) phosphorothioate) 2% and 25% WP (wettable powder), and Guthion® (O,O-dimethyt S -(4-oxo-1,2,3-benzotriazin-8-( 4 H )-ylmethyl) phosphorodithioate) 10% WP produced excellent control for 14 days. In some herds the control was excellent to good for 21 days. Sprays of Diazinon 0.1% and dimethoate 1% provided excellent control for 14 days and good control for 28 days. Ruelene and Co-ral, 0.5%, gave excellent control for 7 days, and fair to good control for 14 days. In general, the dust and pour-on applications provided better control than sprays.