Cattle herd inspections and fly trapping for the detection of the Old World screw-worm fly (Chrysomya bezziana).

Objectives: To compare the sensitivity of inspections of cattle herds and adult fly trapping for detection of the Old World screw-worm fly (OWS).

Procedures: 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.

Field assessment of synthetic attractants and traps for the Old World screw-worm fly, Chrysomya bezziana.

The performance of newly developed trapping systems for the Old World screw-worm fly, Chrysomya bezziana has been determined in field trials on cattle farms in Malaysia. The efficacy of non-sticky traps and new attractants to trap C. bezziana and non-target flies was compared with the standard sticky trap and Swormlure.

Reproduction and recruitment in perennial colonies of the introduced wasp Vespula germanica.

We investigated the genetic structure of perennial colonies of the yellowjacket wasp (Vespula germanica) in its introduced range in Australia and New Zealand. The nuclear genotypes of 712 gynes from 21 colonies, 147 workers from 5 colonies, and 81 males from 4 colonies were assayed at three polymorphic microsatellite loci. The mitochondrial haplotypes of all wasps also were determined for a 450-bp region of the mtDNA using double-stranded conformational polymorphism (DSCP) analysis.

The efficacy of diazinon impregnated ear tags against buffalo fly and resulting weight gains and diazinon residues in meat and milk.

Ear tags impregnated with 20% diazinon were evaluated for their efficacy against the buffalo fly (Haematobia irritans exigua) on beef cattle in southern Queensland. Buffalo fly numbers and weight changes were recorded and diazinon residues in tissues of beef cattle and milk from lactating dairy cattle were assayed at different time intervals after tagging. In 2-efficacy trials conducted over 19 and 20 weeks, the mean numbers of buffalo fly on cattle each fitted with ear tags were 1 to 9 and 0 to 16, respectively, in trials 1 and 2, compared with 44 to 345 and 26 to 306 per head on untreated herds, respectively, despite regular spraying of the untreated herd in trial 1 with cypermethrin to reduce fly burdens.

Dispersal of the Old World screw-worm fly Chrysomya bezziana.

Dispersal of the Old World screw-worm fly, Chrysomya bezziana Villeneuve, was studied in Papua New Guinea by releasing radio-isotope labelled, laboratory-reared flies and collecting their labelled egg masses from sentinel cattle. A log-linear model was developed to describe recapture rate. Distance was found to dominate the model and was represented by a bilinear ('broken-stick') term as log-distance.

Comparison of the predicted impact of a screwworm fly outbreak in Australia using a growth index model and a life-cycle model.

The spatial population dynamics of an Old World screwworm fly, Chrysomya bezziana Villeneuve (OWS), outbreak in Australia have been modelled in two ways. The first model uses weekly growth indices derived from climatic data to predict the adult female population. The second is a detailed cohort life-cycle model.

Cytogenetic variation in natural populations of the Old World screwworm fly Chrysomya bezziana (Diptera: Calliphoridae).

The existence of sibling species in the Old World screwworm fly Chrysomya bezziana would raise serious problems in eradicating this pest if it entered Australia. Cytogenetic variation in C. bezziana was investigated by analyzing pupal trichogen polytene chromosomes.

Cytogenetic variation in natural populations of the Old World screwworm fly Chrysomya bezziana (Diptera: Calliphoridae).

The existence of sibling species in the Old World screwworm fly Chrysomya bezziana would raise serious problems in eradicating this pest if it entered Australia. Cytogenetic variation in C. bezziana was investigated by analyzing pupal trichogen polytene chromosomes.

Mean life expectancy of Old World screwworm fly, Chrysomya bezziana, inferred from the reproductive age-structure of native females caught on swormlure-baited sticky traps.

The reproductive status of native (wild) screwworm fly, Chrysomya bezziana, caught on swormlure-baited sticky traps in Papua New Guinea is described. A total of 1122 females and 25 males were trapped. Of these females 595 were scored for insemination status and stage of ovarian development (on a scale of 2-10) of which 20% were in suitable condition for assignment to first, second and third ovarian cycles.

The efficacy of insecticides against the screw-worm fly (Chrysomya bezziana).

A number of insecticides used for ectoparasite control in the livestock industry were screened for their efficacy against larvae of the screw-worm fly, Chrysomya bezziana, using in vivo and laboratory tests. Proprietary screw-worm fly treatments (after exposure to outdoor conditions for up to 10 days) were also tested against eggs and adults of C bezziana. Three of these were also evaluated on naturally acquired screw-worm infestations.

The potential geographical distribution of the Old World screw-worm fly, Chrysomya bezziana.

The potential geographical distribution and relative abundance of the Old World screw-worm fly, Chrysomya bezziana Villeneuve (Diptera: Calliphoridae) as determined by climate, was assessed using CLIMEX, a computer program for matching climates. CLIMEX describes the relative growth and persistence of animal populations in relation to climate. The observed global distribution of C.

The efficacy of ivermectin against larvae of the screw-worm fly (Chrysomya bezziana).

An in vitro technique for screening systemic insecticides against larvae of the screw-worm fly, Chrysomya bezziana is described. Susceptibilities of screw-worm larvae of different ages to ivermectin (MK-933) were determined. Based on 24 h larval mortality, the LD50 of 1-,2-,3-,4- and 5-day larvae was 0.

The efficacy of some acaricides against screw-worm fly larvae.

Thirteen acaricides used for control of cattle tick in Queensland were evaluated for their potential in the chemical control of the screw-worm fly, Chrysomya bezziana. Laboratory evaluations and in vivo tests using artificially infested cattle were made in Papua New Guinea. Most of the acaricides caused some mortality of screw-worm larvae in infested cattle and in laboratory tests.

Evaluation of insecticide smears for the control of screw-worm fly, Chrysomya bezziana, in Papua New Guinea.

Three new insecticide smear preparations for the control of Chrysomya bezziana larvae infesting wounds of cattle have been tested under field and laboratory conditions and compared with an established preparation EQ 335 which is based on 3% lindane. Two preparations based on 3% coumaphos proved comparable to EQ 335 in the field trials and exhibited more prolonged residual effectiveness in laboratory tests. A smear preparation based on 2.