Systemic Insecticides for Cattle Grub Control12

Abstract

Four animal systemic insecticides: ronnel; Co-Ral^®(O-(3- chloro-4-methylumbelliferone) O, O-diethyl phosphorothioate), also known as Bayer 21/199; Dowco 109 (phosphoramidothioic acid, methyl-O-(4-tert-butyl-2-chlorophenyl) O-methyl ester); and dimethoate, also known as Am. Cyanamid 12880, were investigated for cattle grub control in Kansas during 1957-58. Results showed that November treatment of cattle from the Southern United States with Co-Ral and dimethoate greatly reduced the number of grubs in the backs of the animals but failed to rid the animals of migrating grubs. Dowco 109 as a spray gave a fair reduction of both the encysted and the migratory grubs, as did also the Dowco 109 used as a bolus and as a feed additive in December. September treatments of native cattle with Dowco 109 and Co-Ral sprays gave no appreciable control whereas the Dowco 109 as a bolus gave excellent control. Dowco 109, used as a feed additive on native cattle, gave very favorable results. Ronnel, used as a bolus on native cattle at monthly intervals from June through November, excluding October, greatly reduced the grubs in all treatments except August. A low-level feeding of ronnel for 79 days had no apparent effect upon grub control. No toxic symptoms were noted in any of the cattle treated.