Topical treatment of white-tailed deer with an acaricide for the control of Ixodes scapularis (Acari: Ixodidae) in a Connecticut Lyme borreliosis hyperendemic Community.
The 4-Poster device for the topical treatment of white-tailed deer, Odocoileus virginianus (Zimmermann), against ticks using the acaricide amitraz, was evaluated in a Lyme borreliosis endemic community in Connecticut. As part of a 5-year project from 1997 to 2002, 21-24 of the 4-Posters were distributed at residential sites in Old Lyme, CT, in a core treatment area of approximately 5.2 km(2) in fall 1997. The 4-Posters were active October to mid-December and March into May, corresponding to the peak periods of activity for adult Ixodes scapularis in this particular area. Corn consumption ranged from 361 to 4789 kg/month for October and November and 696-3130 kg/month during April. Usage of 4-Posters by deer generally was high (>90%), except during acorn masts in fall 1998 and 2001. Amitraz was applied by rollers at the estimated rate of 1.3 g active ingredient/ha/year. The abundance of host-seeking I. scapularis nymphs declined significantly (p < 0.001) in the core treatment area, as compared to a control community in Old Saybrook, CT, through 2004, over the project period from 1998 to 2003, from 9.3/100m(2) to 0.97/100m(2), rising to 1.90/100m(2) in 2004. From 1999 through 2003, there were 46.1%, 49.6%, 63.4%, 64.6%, and 70.2% reductions, respectively, in the nymphal tick population in comparison with the untreated community and initial tick abundance in 1998. Control of I. scapularis adults declined to only 19.1% in 2004; 2 years after the treatment of deer was discontinued. Differences in nymphal tick abundance between the control and core treatment area were significant in 1999 (p = 0.042) and highly significant in 2001 (p < 0.001) and 2002 (p = 0.002). The passive topical application to deer of the acaricide amitraz resulted in a significant decrease in the population of free-living I. scapularis nymphs in the treated core in Connecticut.
Stafford
Kirby C
KC
Connecticut Agricultural Experiment Station, New Haven, Connecticut 06504, USA. kirby.stafford@po.state.ct.us
Denicola
Anthony J
AJ
Pound
J Mathews
JM
Miller
J Allen
JA
George
John E
JE
D056810:Acaricides / Q000008:administration & dosage*; D000704:Analysis of Variance; D000821:Animal Feed; D000818:Animals; D001096:Arachnid Vectors / Q000254:growth & development; D025065:Borrelia burgdorferi / Q000254:growth & development; D003237:Connecticut; D003670:Deer / Q000469:parasitology*; D019353:Endemic Diseases / Q000517:prevention & control; D006801:Humans; D018884:Ixodes / Q000254:growth & development; D008193:Lyme Disease / Q000517:prevention & control*; D008873:Mid-Atlantic Region; D009758:Nymph; D012237:Rhode Island; D013983:Tick Control / Q000379:methods*; D013984:Tick Infestations / Q000517:prevention & control / Q000662:veterinary*; D003313:Zea mays
D056810:Acaricides