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Biomedical subjects

D V Hagan

Publications and source records attributed to D V Hagan.

8 recordsLinked to original sources
PubMed1999

Ectoparasites of Brazilian free-tailed bats with emphasis on anatomical site preferences for Chiroptonyssus robustipes (Acari: Macronyssidae).

Seven species of arthropods were recovered from 45 Brazilian free-tailed bats, Tadarida brasiliensis (I. Geoffrey), captured from May 1994 to May 1995 from a roost in Jenkins County, GA. Six species of mites were found infesting the bats, representing 5 families: Macronyssidae, Cheyletidae, Sarcoptidae, Rosensteiniidae, and Uropodidae. The macronyssid mite chiroptonyssus robustipes (Ewing) and the hemipteran bat bug, Cimex adjunctus (Barber), were collected from the host and the roost. C. robustipes was the most abundant mite (2,508 specimens) and the macronyssid Steatonyssus ceratognathus (Ewing) (189 specimens) was the 2nd most abundant mite found infesting the bats. The predatory cheyletid mite Cheyletonella vespertilionis Womersley (51 specimens) was also collected from the bats, and this is thought to be the 1st report of this mite from Georgia. In addition, Teinocoptes sp. (Sarcoptidae, 8 specimens), Nycteriglyphus sp. (Rosensteiniidae, 8 specimens), and uropodid mites (5 specimens) were removed from the bats. Of the 45 bats examined, all 30 females and 14 of 15 males were infested with C. robustipes. Twenty-three bat anatomical areas were designated and all C. robustipes mites were counted to ascertain anatomical preference. This mite was significantly more abundant on the ventral wing membrane areas posterior to the radiusulna and on the lower torso. Protonymphs of C. robustipes predominated on the wing membranes of the bats, whereas adult mites were more concentrated on the torso and head.

Animals↗
PubMed1995

Two-tier box trap catches Chrysops atlanticus and C. fuliginosus (Diptera: Tabanidae) near a Georgia salt marsh.

A new two-tier box trap designed for collecting Chrysops was tested on St. Simons Island, GA. The bottom box was constructed of plywood 1.2 m wide with the sides painted flat black on the outside and glossy off-white on the interior. The upper box was of similar construction, but painted glossy off-white. The bottom edge of the lower box was 0.6 m above the ground, and the bottom edge of the upper box was 1.8 m above the ground (0.6 m above the top of the lower box). In some trials, a glossy black beach ball was suspended below the center of the box and 1-octen-3-ol was dispensed midway between the boxes. Significantly more Chrysops fuliginosus Wiedemann and C. atlanticus Pechuman were collected in the upper box than in the lower box. A glossy spherical target and the presence of 1-octen-3-ol increased the catch of C. atlanticus in the upper box.

Animals↗
PubMed1994

Culicoides responses to 1-octen-3-ol and carbon dioxide in salt marshes near Sea Island, Georgia, U.S.A.

The semiochemicals carbon dioxide (CO2) and 1-octen-3-ol (octenol) were evaluated as attractants at several release rates, alone and in combination, for the major coastal species of biting midges in Georgia: Culicoides furens, C. hollensis and C. melleus (Diptera: Ceratopogonidae). The data show that CO2 is an effective attractant for the females of all three species, but each has a different response pattern. In contrast, octenol was an effective attractant only for C.furens, either alone or in combination with CO2; octenol had a repellent effect on the other two species. The combination of octenol and CO2 had a synergistic effect on the collections of C.furens.

Analysis of Variance↗
PubMed1994

Comparative study of mouthparts of four species of Culicoides from Tibet.

Mouthparts of four species of Culicoides from Tibet were studied by light and scanning electron microscopy (SEM). Photomicrographs were made of the mandible, labrum, hypopharynx, lacinia, and the sensory pit of the third palpal segment for each of the four species. Values for eighteen characters of five structures are presented graphically. Mean values for ten of the eighteen characters evaluated were significantly greater for C. circumscriptus and C. mamaensis than for C. maculatus and C. tibetensis. Photomicrographs revealed specific differences in camber and pitch of the fifth mandibular tooth, in size and location of the subapical labral sensillae, in size of the teeth of the hypopharynx, and in size and depth of the palpal sensory pit and number of sensillae per pit.

Animals↗
PubMed1992

Seasonal abundance of Lutzomyia shannoni (Diptera: Psychodidae) on Ossabaw Island, Georgia.

Population dynamics of Lutzomyia shannoni were monitored from April 1986 through December 1987 on Ossabaw Island, Ga. Most (99%) of the 19,788 adult sand flies were collected in light traps supplemented with dry ice; less than or equal to 1% were aspirated from diurnal resting sites. Adult sand flies first appeared in April and were followed by peaks of abundance during May 1986, and May and July 1987. Numbers of adults captured fell rapidly in October and November 1986 and in September and October 1987. No specimens were collected in December 1986 or in March, November, and December 1987. Light trap catch was affected positively by mean nightly air temperature and negatively by rainfall 14 d before collection, but not by wind speed or moon phase. Vesicular stomatitis viral activity, as measured by antibodies in feral and domestic swine, roughly corresponded to the seasonal appearance of adult L. shannoni during 1986 and 1987. Significantly more adults (72%) were collected in light traps at ground level (0.5m) than at heights of 4 and 8m. Most resting adults were collected from dark, moist tree holes and cavities of various hardwoods.

Animals↗
PubMed1986

Seasonal and meteorological effects on activity of Chrysops variegatus (Diptera: Tabanidae) in Paraguay.

Activity of adult, female Chrysops variegatus was studied for 17 months near Aregúa, Paraguay. The population was sampled by walking along a forest path while swinging an insect net. Results of sampling indicated that this species followed no seasonal pattern of activity. Fluctuation in activity appeared to follow a 13-week cycle. Meteorological effects on activity were studied during 2 weeks of peak tabanid abundance. Temperature, humidity, and wind accounted for 89% of the variation observed during the 23 weeks. Activity of this species observed on a particular day appeared to be the result of the overall population level and meteorological conditions at the time.

Animals↗