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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Pheromonal mediation of reproductive behavior in the brown tree snake

Greene, Michael John 18 June 1998 (has links)
In animals, reproductive behaviors serve to attract individuals together during the breeding season and to coordinate the behavioral and physiological states of individuals so that mating can successfully occur. In snakes, the various reproductive behaviors including courtship, mating, courtship inhibition, male combat and trailing are mediated primarily by pheromones. Pheromones are naturally produced chemical signals that influence the physiology or behavior of a conspecific when released by one individual into the environment. The research included in this study was designed to characterize the role pheromones play in the mediation of reproductive behaviors of the brown tree snake (Boiga irregularis) a rear-fanged, arboreal colubrid native to Australia, Papua-New Guinea and the Solomon Islands. Much attention has been paid to this species as it is an introduced pest species on the Pacific island of Guam where it has caused considerable economic and ecological damage. In order to create behavioral bioassays designed to experimentally determine the role pheromones play in the mediation of brown tree snake reproductive behavior, the complete repertoire of courtship, mating and male combat behaviors were described. Male brown tree snakes display combat and courtship behaviors similar to other colubrid species while female brown tree snakes take a very active role in courtship, displaying behaviors that both release and inhibit male courtship. These data represent the first description of any reproductive behaviors in this species and one of only a few studies examining the reproductive behaviors of a tropical species. A behavioral bioassay measuring the release of male courtship behavior was utilized to isolate and characterize the female sex pheromone of this species as a suite of non-polar, non-volatile skin lipid molecules. Using another bioassay, the pheromonal inhibition of male courtship behavior by a volatile pheromone originating from female cloacal secretions was characterized. Lastly, pheromone mediated mate attraction was examined by determining the abilities of male brown tree snakes to follow conspecific pheromone trails during the breeding season. Male brown tree snakes possess the ability to follow both male and female pheromone trails but did not, however, discriminate between male and female pheromones trails when given a choice. / Graduation date: 1999
42

Pink bollworm pheromone trapping: analysis of trap design, pheromone substrate and field spacing

Hoffmann, Michael Peter January 1978 (has links)
No description available.
43

The role of selected frass chemicals and cuticular lipid components in the orientation of certain larval Tenebrionidae /

Weaver, David K. (David Keith) January 1989 (has links)
The larvae of Tenebrio molitor Linne and Alphitobius diaperinus (Panzer) both aggregated upon substrates treated with aqueous extracts of conspecific larval frass. Lactic acid is a pheromone in the frass of both species. Alphitobius larvae were attracted to lactic acid, while lactic acid caused Tenebrio larvae to arrest. / Propionic acid is a repellent pheromone present in Tenebrio frass, but the lactic acid-induced response is dominant. The role of these chemical factors in population orientation of the larvae of these mealworm species is discussed. / The cuticular lipids of the larvae of both species contained close-range attractants that had a role in aggregate formation. The Tenebrio cuticular lipid pheromone is predominately 8,9-pentacosanediol. The Alphitobius cuticular pheromone is a mixture of at least two compounds. / The ecological preferences of these larvae suggested that these aggregation pheromones increased the density of individuals per unit volume. This increased density had varying effects on the physiological development of Tenebrio individuals.
44

Structure and function of the moth mushroom body /

Sjöholm, Marcus, January 2006 (has links) (PDF)
Diss. (sammanfattning) Alnarp : Sveriges lantbruksuniv. / Härtill 5 uppsatser.
45

The role of selected frass chemicals and cuticular lipid components in the orientation of certain larval Tenebrionidae /

Weaver, David K. (David Keith) January 1989 (has links)
No description available.
46

Physiological control of calling, pheromone release, and pheromone production in the female gypsy moth, Lymantria dispar.

Tang, Juliet D. 01 January 1986 (has links) (PDF)
No description available.
47

Establishment Of Blackberries And Detection And Management Of Raspberry Crown Borer

Heard, Edward 09 December 2006 (has links)
Evaluations of tactics for detection and management of raspberry crown borer, RCB, Pennisettia marginata (Harris) on blackberries were performed in Mississippi from January 2005 - July 2006. Randomized split plots with infested blackberries and certified nursery stock of two recommended cultivars, thorny ?Chickasaw? and thornless ?Apache? were planted. Pest management tactics targeting RCB included drenches: chemical insecticide bifenthrin, recently registered for RCB management; experimental pesticide E2Y45; and entomopathogenic nematodes Steinernema feltiae. Insect pheromones (E,Z)3-13-octadecadien-1-ol and (E,Z)3-13-octadecadien-1-yl-acetate were evaluated as RCB lures. Effects of fungicides captan, pyraclostrobin + boscalid, lime-sulfur and insecticide acetamiprid on viability and infectivity of entomopathogenic nematode species, S. feltiae and Heterorhabditis bacteriophora were evaluated in laboratory bioassays with host greater wax moth larvae. RCB larvae and soil pests on and around infested blackberry plants were observed. Bait traps with 5 mg of (E.Z)3-13-octadecadien-1-ol captured an adult RCB on October 19, 2005. Laboratory bioassays indicated that lime-sulfur and pyraclostrobin + boscalid decrease nematode movement and infectivity.
48

Analysis of the mandibular pheromone of living honeybee queens using non-destructive sampling techniques

Masemene, Monyadiwa Martha January 2008 (has links)
Thesis (MSc.(Chemistry)) - University of Pretoria, 2008. / Includes bibliographical references
49

Thunderstorm phobia in dogs

Wallentine, Kari D. January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Janice C. Swanson / Canine thunderstorm phobia is a common, frustrating, and complex problem that, due to the often severe nature of the clinical signs, can lead to canine relinquishment to shelters. Although a potentially treatable disorder, existing treatment options have several limitations and variable success rates. Three survey-based studies were conducted to increase the knowledge base for canine thunderstorm phobia. The first study distributed 1445 surveys through 16 Kansas veterinary clinics to determine the prevalence and characteristics of thunderstorm phobic dogs and assess differences between affected and non-affected dogs. Of 463 dogs surveyed, 240 were thunderstorm phobic as assessed by their owners. Severe weather warning systems may play a role in thunderstorm phobia. Thunderstorm phobic dogs were more fearful when exposed to tornado sirens, both during actual storms and siren testing, indicating a possible effect of classical conditioning. No differences were noted regarding sex, breed, pedigree, or neuter status. Most affected dogs preferred to be indoors remaining near their owners. The second study distributed 1600 surveys through eight Kansas animal shelters to determine the prevalence of relinquished dogs with thunderstorm phobia. Other reasons for relinquishment were also assessed. A fear of thunder was among the least common behavioral problems leading to relinquishment in dogs. Only a quarter of owners had visited a veterinarian for assistance with behavioral problems. The third study involved the administration of dog appeasing pheromone (DAP) in a double-blind, placebo-controlled, randomized clinical trial to assess its efficacy as a sole treatment for thunderstorm phobia. Data was collected from 60 dog owners using behavioral assessment questionnaires. In dogs given the placebo, six behaviors significantly improved, with another eleven showing a numerical trend toward improvement. However, in dogs given DAP, significant improvement was seen in three of these same behaviors. Consequently, these results do not indicate the potential use of DAP for reducing fearful behaviors associated with thunderstorm phobia when compared to negative controls. Information gained from these studies allows veterinarians and behavioral researchers to better understand the extent of this behavioral disorder and hopefully stimulates future research to find new and more effective ways to treat it.
50

Vinylsilanes and allysilanes in electrophilic substitution reactions : stereocontrolled synthesis of insect sex pheromones

Koumaglo, Mensah-Dzraku Kossi January 1985 (has links)
No description available.

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