Impact of Rabon (R) oral-larvicide on the seasonal abundance of insects in dairy cow manure in a semi-arid area

Abstract

An intersive study of insect fauna in accumulated bovine manure was conducted from mid-Arpril through mid-October, 1975, on two dairy farms in the Mesa-Chandler area of south-central Arizona. Insect fauna was sampled by water flotation of manure, emergence trapping and resting fly counts. Musca domestica L. was the major noxious symbovine dipterous species collected. Tables of all predators, parasitoids, and scavenger groups collected are presented and seasonal abundance graphs for the primary inhabitants are included. In concert with the faunistic studies the effect of the feed additive insecticide stirofos (Rabon® oral-Larvicide, 2-chloro-1-(2,4,5-trichlorophenyl) vinyldimethyl phosphate) was evaluated. Reductions in fly population ranged from 27% to 87% depending upon the sampling method. Results of insecticidal activity on non-target groups are discussed and graphically depicted.