Physical and bio-control methodologies for integrated management of buffalo fly-Haematobia exigua (Diptera: Muscidae)

Abstract

Haematobia exigua, the buffalo fly, is a common ectoparasite of buffaloes and cattle in India causing economic losses and underlines the necessity of effective control strategies against them. The present study was planned to evaluate larvicidal activity of few methods for physical and biological control for integarated management of Haematobia exigua flies.  Out of four bacterial bio-control agents evaluated by in-vitro assay and Probit analysis, two bacteria i. e. Bacillus thuringiensis var israelensis and Bacillus thuringiensis var kurstaki showed excellent larvicidal activity against H. exigua with LC50 value of 134 and 135 mg per liter of water respectively. Whereas, other two bacteria i. e. Bacillus weihenstephanensis WSBC and KBAB4 failed to show desired larvicidal activity. It can be concluded that B ti and B tk have future as effective bacterial agents (BCAs) in the control and integrated management of buffalo and horn fly. An experiment was conducted in the laboratory and on field for judging the efficacy of a physical method of tightly covering dung pats with polythene sheet for control of larvae of H. exigua. The laboratory result showed only 14.73% larvae were survived and developed per 100 gm of the faeces in the pot covered with polythene sheet as against significantly higher number 78.33% in the control group. During field trial, average larval count from dung pits before the experiment was 86.33 per 250 gm of faeces and it has been significantly reduced to 11.80 after covered with polythene sheets for two weeks.  It indicated that physical method of covering the dung pits works immensely and thus can be inducted in IPM program as one of the effective physical control alternatives.