Cattle herd inspections and fly trapping for the detection of the Old World screw-worm fly (Chrysomya bezziana).
OBJECTIVE
To compare the sensitivity of inspections of cattle herds and adult fly trapping for detection of the Old World screw-worm fly (OWS).


METHODS
The incidence of myiases on animals and the number of OWS trapped with LuciTrap®/Bezzilure were measured concurrently on cattle farms on Sumba Island (Indonesia) and in peninsular Malaysia (two separate periods for the latter). The numbers of animal inspections and traps required to achieve OWS detection at the prevalent fly densities were calculated.


RESULTS
On Sumba Island, with low-density OWS populations, the sensitivity of herd inspections and of trapping for OWS detection was 0.30 and 0.85, respectively. For 95% confidence of detecting OWS, either 45 inspections of 74 animals or trapping with 5 sets of 4 LuciTraps for 14 days are required. In Malaysia, at higher OWS density, herd inspections of 600 animals (twice weekly, period 1) or 1600 animals (weekly, period 2) always detected myiases (sensitivity = 1), while trapping had sensitivities of 0.89 and 0.64 during periods 1 and 2, respectively. For OWS detection with 95% confidence, fewer than 600 and 1600 animals or 2 and 6 LuciTraps are required in periods 1 and 2, respectively.


CONCLUSIONS
Inspections of cattle herds and trapping with LuciTrap and Bezzilure can detect OWS populations. As a preliminary guide for OWS detection in Australia, the numbers of animals and traps derived from the Sumba Island trial should be used because the prevailing conditions better match those of northern Australia.
Agri-Science Queensland, Department of Agriculture, Fisheries and Forestry, Ecosciences Precinct, 41 Boggo Rd, Dutton Park, Queensland, 4102, Australia. rudure@iinet.net.au.
R
R
Urech
S
S
Muharsini
R S
RS
Tozer
Sumartono
P E
PE
Green
G W
GW
Brown
J P
JP
Spradbery
D G
DG
Mayer
Y
Y
Tack Kan
A
A
Kison
D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology / Q000469:parasitology*; D004175:Diptera / Q000254:growth & development*; D015994:Incidence; D007214:Indonesia / Q000453:epidemiology; D008296:Malaysia / Q000453:epidemiology; D009198:Myiasis / Q000453:epidemiology / Q000469:parasitology / Q000662:veterinary*; D015995:Prevalence; D012610:Screw Worm Infection / Q000453:epidemiology / Q000469:parasitology / Q000662:veterinary*; D012680:Sensitivity and Specificity
LuciTrap®; Old World; fly trapping; herd inspections; screw-worm fly