SEARCH · Search PubMed
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
The material of 22302 flies of Anthomyiidae, Muscidae and Calliphoridae collected by trap-method in Cuba 1966 was qualitatively and quantitatively analysed. Relative density, seasonal incidence and food preference were ascertained in 20 species. In potential vectors of human diseases the ecological characters and classification of synanthropy are given.
A simple, rapid method using restriction fragment length polymorphisms (RFLPs) within the internal transcribed spacer (ITS) regions of the ribosomal DNA gene repeat allows identification of insects and other organisms. We used the method to identify the morphologically similar Diptera larvae that are important in forensic entomology for estimating the time and location of death. Polymerase chain reaction (PCR) was used to amplify a region from the 18S to the 28S rRNA genes. The ITS1 and ITS2 regions provided variation between species and homogeneity within species, with the exception of Cochliomya macellaria. Combinations of the restriction enzymes DdeI, HinfI and Sau3AI provided diagnostic bands for identification of the ten species from three families of Diptera (Calliphoridae, Muscidae and Sarcophagidae).
Forty species belonging to 14 genera of the family Muscidae were found so far in Korea. They are described in this paper and 5th sternites, forceps and male genitalia are illustrated. Eleven species recorded by Kobayashi (1918-1940) and 16 species by Hori (1952) were revised and redescribed in this paper. The key to the species of the muscid flies in Korea are also presented.
Flies from different geographical parts of Thailand were collected to study their medical importance as well as making a zoogeographical study. After examination, 32 species of 10 genera, Orthellia, Mitroplatia, Morellia, Pyrellia, Rypellia, Haematobia, Haematobosca, Stygeromyia, Haematostoma and Stomoxys, belonging to Muscidae were identified and these are reported in this paper. Some of these are newly recorded ones from this country. This study is based on the specimens available in the authors' collection.
The authors studied the occurrence of haematophagous and non-haematophagous flies in three different collecting sites in the Toro Game Reserve in western Uganda, at the dry season peak (January, February), using canopy trap and baited traps. Collected were 6 species of Tabanidae, 1 species of Glossinidae, 24 species of Muscidae, 3 species of Calliphoridae, 4 species of Sarcophagidae and 3 species of other families.
Hydrotaea aenescens (Wiedemann), the black dump fly, is a potential biological control agent originally from the western hemisphere, now found in many parts of the Palearctic region except for the United Kingdom, where it cannot be imported for any reason. A complication of classical biological control is the problem of strain identification, as one must be able to somehow mark or follow a particular strain that has been introduced into the field or is contemplated for release. Gas chromatographic analysis of the surface hydrocarbons of pooled and individual dump fly adults resulted in reproducible hydrocarbon patterns that differentiated widely distributed strains of H. aenescens and showed similarities between strains that were related. Sexual dimorphism was observed in the surface hydrocarbons. Conspecific similarities included identities of the hydrocarbons found in colony material collected worldwide, with differences being found in the quantities of compounds present.
Polyacrylamide gel electrophoresis was used to resolve allozymes in the cosmopolitan blood-feeding stable fly, Stomoxys calcitrans (L.). Nineteen of 38 loci were polymorphic (53%). Mean heterozygosities among all loci and among only polymorphic loci were 0.096 and 0.182, respectively. These gene diversity measures are about half those among other muscid Diptera. Variation in gene frequencies was examined in 10 natural stable fly populations from Iowa and Minnesota. Gene frequencies were homogeneous at five of eight loci among six populations in 1990 and eight of eight loci among four populations in 1992. Wright's F statistics showed no significant departure from random mating among stable flies. It was concluded that gene flow compensates for any local differentiation in stable fly populations.
Spiracles are major respiratory openings in the exoskeleton of insects. Oxygen, a necessary gas for cell activity, must pass through the spiracle to enter the respiratory system. In this study, we investigated the fine structure of spiracles of adult females of Musca domestica L. and Hydrotaea chalcogaster (Wiedemann), both medically important fly species in many parts of the world, by utilizing scanning electron microscopy. The mesothoracic spiracle of M. domestica is large and elongate-oval in shape, with its anterior end being gradually tapered. The outer surface is densely covered with slender setae of variable distribution and orientation. The metathoracic spiracle is semicircular or D-shaped, with its rim possessing long, fine, inwardly curved setae. A net-like valve or sieve plate, which has a smooth rim with swollen surface, is located within the atrium of this species. The abdominal spiracles are circular with a symmetrically swollen peritreme surrounding the opening. The inner filtering apparatus is composed of many spiral tubes, each possessing many small spines. As for H. chalcogaster, the tapering mesothoracic spiracle is covered with long setae arranged consistently inward from the peritreme, giving it a "combed" appearance. The metathoracic spiracle is similarly arranged but triangularly rounded in shape, with the anterior and posterior rims possessing long fine setae. The net-like valve within the atrium has a smooth, swollen rim, whereas the inner edge of the atrium bears short, slender setae where it meets with the peritreme of the spiracle. The abdominal spiracles of this species look similar to that of M. domestica, with the exception of the filtering apparatus that bears only a few small spines. The function of these spiracles is discussed.
The doses lethal to 50% of the insects (LD50 values) obtained for a strain of Hydrotaea aenescens (Wiedemann) adults from a layer farm revealed higher sensitivity to 16 insecticides than those recorded for the susceptible WHO/SRS strain of the housefly. Because H. aenescens adults are about half the size of the housefly, the chemical compounds used for adult control may jeopardize the survival of Hydrotaea populations released in animal confinement houses. An efficient and economical combined application of biological and chemical control methods is possible only if the local management conditions and the dissimilar behavior of the adults of the two species are taken into consideration during the use of insecticides. Other suggestions and implications are further discussed.
Late spring treatment of cattle with a single dose of pour-on ivermectin (0.5 mg kg-1 body weight) resulted in reduced horn fly populations for approximately 6 weeks, with percentage efficacy exceeding 80% for at least 26 days post-treatment. Bioassay with house flies of dung from treated cattle demonstrated suppression of fly emergence for 11 days post-treatment. The subsequent increase in horn fly numbers on the treated herd was predicted by a developmental rate equation interpreted by the time of cessation of larval fly inhibition in field dung.
The concentration of moxidectin, a macrocyclic lactone endectocide, in the blood serum of cattle resulting from single and daily subcutaneous injections and oral dosing was determined as a function of time. When given as a single subcutaneous (SC) injection, the drug peaked between 4 and 6 h post-treatment. As a single oral dose, the peak serum level occurred at 1 day post-treatment. Daily SC injections and oral doses resulted in a gradual increase in blood serum level over the 21 days of treatment but did not reach a plateau during this time. Horn flies, Haematobia irritans (Linnaeus), feeding on the blood of treated cattle drawn on Day 21 of daily treatment showed a decline in survival and egg production, but a negligible effect on egg hatching. Dose-mortality data on adult horn flies showed an LC-50 and LC-90 value of 10 ppb and 19 ppb in the blood, respectively. Moxidectin was also found to have larvicidal activity against the immature stages of the horn fly in the manure of treated cattle. Moxidectin administered at 100, 50 and 25 micrograms kg-1 as a daily oral medication was 100% effective in eliminating trichostrongyle egg counts by Day 3 of the treatment. Counts remained negative to the end of the trial.
Diapausing face flies, Musca autumnalis (De Geer), are characterized by the presence of hypertrophied fat bodies (HFB) and arrested ovarian development. A total of 1752 face flies were caught around cattle in south-central Sweden during the last 5 weeks of the grazing season, in August-September. Females in this material (1139) were examined in search of HFB and to determine their reproductive status. It was assumed a priori that gonoactive flies would not undergo diapause. Flies were also dissected in search of the nematodes Parafilaria bovicola (Tubangui), Thelazia spp. and Heterotylenchus autumnalis (Nickle). Only females were found to be infected, of which 0.6% contained P. bovicola, 0.6% Thelazia spp. and 1.4% H. autumnalis. Both gonoactive and nongonoactive flies were infected with P. bovicola and Thelazia spp. Only nongonoactive Thelazia-infected flies had HFB, which is suggestive of flies able to overwinter. In the Heterotylenchus-infected flies with HFBs, arrested development (hypobiosis) of the nematode was recorded.
The fly Haematobia irritans irritans is one of the most important ectoparasites in cattle production, due to its ability to suck large amounts of blood. This report describes the purification and characterization of a serine proteinase inhibitor (HiTI) present in H. i. irritans head and thorax extracts. The HiTI purified by affinity chromatography on trypsin-Sepharose has a molecular mass of 7029Da by MALDI-TOF mass spectrometry. HiTI inhibited bovine trypsin, human neutrophil elastase, and a trypsin-like enzyme purified from H. i. irritans abdomen with dissociation constants of 0.57, 1.30, and 0.20nM, respectively. The HiTI partial amino acid sequence allowed its classification into the BPTI-Kunitz-type family. An HiTI cDNA fragment was cloned in the pGEMT vector using RT-PCR. The translated amino acid sequence of HiTI cDNA confirmed a unique Kunitz-type-domain protein. Our results suggest that HiTI could control some endogenous enzyme, e.g., the H. i. irritans trypsin-like protein.
Hydrotaea chalcogaster is a fly species of medical and forensic importance in many parts of the world. In this study, we investigated the sensilla of the antenna and palp of the adult female fly using scanning electron microscopy. The antennal scape has one type of sensillum, the sharp-tipped sensillum trichodeum; whereas, the antennal pedicel also possessed this type of sensillum in addition to an unidentified type. Three types of sensilla were found on the flagellum: (1) sensilla basiconica, with both large and small sensilla basiconica showing wall pores, (2) sensilla coeloconica, with a smooth surface, and (3) sensory pits, with wall pores of pegs. The arista is located dorso-laterally on the flagellum and has three segments. Short microtrichia are located around the distal end of its second segment and on the proximal half of the third segment. Both large sharp-tipped sensilla chaetica and small sensilla basiconica with wall pores were observed on the palps. Results of this study contribute to our overall understanding of the ultrastructural morphology of sensilla on the antenna and palp of H. chalcogaster.
The population density of horn flies was evaluated in the year 1998 in the municipality of Araçatuba, São Paulo Brazil, in relation to temperature and rainfall conditions. Two lots of 30 Nellore steers (Bos indicus) were used which had no insecticidal treatment and were naturally infested with horn flies. The infestations were assessed by two counting methods, i.e., the traditional estimate method and the filming method. The highest fly frequencies were recorded in spring, summer, autumn and the lowest frequencies were recorded in winter. The increase in fly number was positively correlated (P<0.05) with rainfall.
Populational flux of the adult phase of Stomoxys calcitrans was observed in the municipal district of Pedro Leopoldo, Minas Gerais, Brazil. Three biocenoses were selected for the study: stable agrobiocenosis, pastural agrobiocenosis and eubiocenosis. The occurrence and the populational flux of the insects, using the Magoon trap for their capture, were established. For each trap located in different biocenoses, a crossbred calf (Bos taurusxBos indicus) approximately 6-month-old was used as "live bait," exposed weekly for 48h in the traps. Of the three agrobiocenoses studied, the stable agrobiocenosis contributed the greatest number of specimens of. S. calcitrans captured, corresponding to 96.9% of the total flies of this species collected. S. calcitrans shows seasonal behavior for approximately 6 months (spring and summer being the rainiest months of the year). The population peaked during the months of November and December. During the months of July and August, there was no capture of flies.
A trained observer direct count method to measure horn fly population was evaluated to determine the reliability (inter-observer agreement) and its validity when compared with a "gold standard" method (video film). All the counts were performed with the animals restrained in a chute in a single herd. A direct count of horn flies by each of two observers on opposite sides of the animal was made. In addition a videotape recording of the counting surface on each animal was made. Horn flies were counted on 80 cows in the morning twice monthly from 22 October 1999 to 24 March 2000. The correlation between observer counts was high as was the correlation between observer counts and counts made from a videotape recording. Direct counts by trained observers were highly reliable and had good validity. However, videotape recording can be useful when the horn fly population is high, because it is faster in the field than the direct count method. The results of this study suggest that the direct count method can be used with confidence under field conditions.
Between 1999 and 2002, the effect of mid-season doramectin treatments on the level of resistance in pyrethroid-resistant horn fly populations was examined at three separate Louisiana State University Agricultural Center research stations. The cattle were treated with pyrethroid ear tags in all years at all farms, and each farm received a mid-season doramectin treatment in 1 year. The number of weeks of control at Red River was 11 weeks higher in the year following the mid-season treatment of doramectin. At Macon Ridge, the number of weeks of control was 2 weeks higher in the year following the doramectin treatment. No change was observed at St. Joseph. The LC50s for fly populations tested at Macon Ridge and St. Joseph were found to increase for pyrethroids from the spring populations to the fall populations between 2000 and 2002. The LC50s for fly populations at Red River followed the same trends except in 2000, the year when the doramectin treatment was administered. Flies collected pre and post-treatment each year from St. Joseph and Red River were assayed for two alleles (kdr and skdr) associated with target site resistance to pyrethroids. Flies collected pretreatment at Macon Ridge in 1999 also were assayed for the kdr and skdr, and this population of flies had a frequency of 85.6% R-kdr alleles. At St. Joseph and Red River there was a general decline in the frequency of homozygous susceptible skdr (SS-skdr) and homozygous susceptible kdr (SS-kdr) individuals, as well as a general increase in homozygous resistant skdr (RR-skdr) and homozygous resistant kdr (RR-kdr) individuals, during the 4-year study. At both sites, the frequency of R-kdr alleles increased significantly in flies collected in the fall compared to flies collected in the spring with the exception of Red River in 2000, when dormacetin was applied. The frequency of the R-kdr alleles was significantly higher in flies collected in the fall compared to flies collected in the spring in the following year at both sites in two out of three comparisons. The frequency of R-skdr alleles was significantly lower in fly populations tested in the spring compared to fly populations tested in the fall at both farms in years when doramectin was not applied but there were no differences in the years when doramectin was applied. The frequency of R-skdr alleles was significantly higher in fly populations tested in the fall compared to in the spring the following year during all three comparisons at Red River and in one of three comparisons at St. Joseph.