Autosterilization of the house fly, Musca domestica (Diptera: Muscidae) in poultry houses in north-east India

1997

Medical Vet Entomology

A deterministic simulation model is used to explore the potential for control of the sheep blowfly, Lucilia sericata, using odour-baited targets. The simulations show that the ambient temperatures of 15 degrees C or 20 degrees C, 13% and 24% of the females present in a population would need to be killed per day, respectively, to prevent the population growing from its initial spring density during the summer blowfly season. In contrast, if both sexes could be sterilized, so that sterilized males were also able to disrupt the fertility of unsterilized females, only 6.5-13% of both sexes would need to be attracted and sterilized at 15 degrees C or 20 degrees C respectively. To examine whether these numbers of individuals could be attracted by targets baited with liver and sodium sulphide, mark-release-recapture studies in sheep pastures were used to quantify sticky target efficiencies. The percentage of the L.sericata population caught on any one day was shown to be positively related to average ambient temperature. At 15 degrees C each sticky target caught approximately 13% and at 20 degrees C, 41% of the females within a 20 m radius. The results indicate that, at ambient temperatures between 15 and 20 degrees C, if distributed at a density of approximately 5/ha, targets baited with liver and sodium sulphide could effectively suppress a population of L.sericata. Lower densities of targets would be required if they were able to sterilize both sexes rather than kill or if more attractive synthetic semiochemical baits could be developed.

Section: Discussionmentioning

confidence: 99%

The potential for control of the blowfly Lucilia sericata using odour‐baited targets

1997

Medical Vet Entomology

“…This is because individuals sterilized directly do not reproduce and sterilized individuals can also decrease the reproductive output of the remaining, non-sterilized individuals in the population, as any cross between a sterilized and a normal fly will produce non-viable progeny . Effective autosterilizing systems have been developed for the tsetse flies, Glossina pallidipes and G. morsitans morsitans, using the juvenile hormone analogue pyriproxyfen (Hargrove & Langley, 1990) and for the house fly, Musca domestica, using the chitin synthesis inhibitor triflumuron (Howard & Wall, 1996a). It has been shown that triflumuron may also be a suitable agent for the incorporation into a target control system for L. sericata, as it causes transovarial ovicidal effects following ingestion by adult female L. sericata and males are capable of transferring effective doses to unexposed females following mating (Smith & Wall, 1998).…”

Section: Introductionmentioning

confidence: 99%

Suppression of the blowflyLucilia sericatausing odour‐baited triflumuron‐impregnated targets

1998

Medical Vet Entomology

Field trials were carried out in 1995 and 1996 on farms in the south-west of England to assess the extent to which odour-baited targets could be used to suppress populations of the ectoparasitic blowfly, Lucilia sericata, in sheep pastures. Targets were constructed from 41 x 41 cm squares of aluminium sheet, covered by white cloth which had been dipped in a mixture of sucrose solution (50% w/v) and the chitin synthesis inhibitor triflumuron (10% suspension concentrate). Each target was baited with approximately 300 g of liver and sodium sulphide solution (10%). Three matched sheep farms were used in the trials. In 1995, triflumuron-impregnated targets were placed around the periphery of sheep pastures at one of the farms in late June, at approximately one target per hectare. In 1996, triflumuron-impregnated targets were placed around the periphery of sheep pastures of a second of the farms in early May, at approximately five targets per hectare. Each year, five sticky targets, used to monitor the L. sericata populations, were also placed in fields at the experimental and the other two farms, which acted as controls. In 1995, the results provided some, although inconclusive, evidence that the triflumuron-impregnated targets had reduced the numbers of L. sericata relative to the populations on the two control farms. In 1996, however, the density of L. sericata on the experimental farm was reduced to almost zero and remained significantly lower than on two control farms throughout the period during which the triflumuron-impregnated targets remained in the field. The results are discussed in relation to the use of triflumuron-treated targets as a practical means of controlling L. sericata and sheep blowfly strike.

“…In contrast, the juvenile hormone analogue pyriproxyfen, has been shown to exhibit high levels of thermal-and photo-stability (Langley et al, 1993). No decline in the concentration of triflumuron with time was observed on sucrose-baited targets hung in poultry houses in India (Howard & Wall, 1996b). However, as these targets were under cover any effects of rain or sunlight on the triflumuron were minimised.…”

Section: Discussionmentioning

confidence: 99%

“…This may be the result of direct effects on males, through impairment of spermatogenesis or insemination ability or, alternatively, exposed males may simply pick up sufficient active ingredient on their bodies to be able to pass on effective doses to unexposed females during mating (Howard & Wall, 1996a). Utilising these effects, triflumuron has been incorporated into a target autosterilizing system for the successful control of M. domestica in poultry houses in India (Howard & Wall, 1996b). Hence, the aim of the work, described in this paper, was to determine whether the chitin synthesis inhibitor, triflumuron, could disrupt the reproductive output of L. sericata and, if so, whether this chemical has potential for incorporation into baited targets for sheep blowfly control.…”

Section: Introductionmentioning

confidence: 99%

Effects of targets impregnated with the chitin synthesis inhibitor triflumuron on the blowfly Lucilia sericata

Entomologia Exp Applicata

1998

The effects of exposure of adults of the blowfly Lucilia sericata (Meigen) for 24 h to cloth targets impregnated with the chitin synthesis inhibitor triflumuron plus sucrose or sucrose only, were considered. When both male and female L. sericata were exposed to targets treated with sucrose only, the percentage egg hatch varied between 60–75%. When both sexes were exposed to targets treated with 10% triflumuron plus sucrose the percentage egg hatch varied between 3–7%. When females alone were exposed to triflumuron, prior to the introduction of unexposed males, egg hatch varied between 4–14%. The exposure of males alone to 10% triflumuron treated targets, prior to the introduction of unexposed virgin females, did not give any consistent significant decrease in the mean percentage egg hatch. However, repetition of this trial with males exposed to targets treated with 15 or 20% triflumuron, resulted in a percentage egg hatch of 3.1% and 10.3%, respectively. These results suggest that at relatively high target concentrations, males can transfer effective doses of triflumuron to unexposed virgin females. The exposure of adults to triflumuron treated targets did not significantly increase the mortality of either male or female L. sericata. Furthermore, bioassays showed that there was no significant decline in the ovicidal effectiveness of targets treated with 10% triflumuron and sucrose solution following exposure to sun and rain for up to 8 weeks in 1995 and 1996. The results suggest that targets treated with triflumuron suspension concentrate and sucrose may form the basis of an effective system for the control of L. sericata in the field. However, the relatively high concentrations of triflumuron required and the low efficiency with which males are able to transfer effective doses to unexposed females may diminish one of the main theoretical advantages of using a chitin synthesis inhibitor, such as triflumuron, over a conventional insecticide.