Sheep blowfly research. I. A survey of maggot collections from live sheep and a note on the trapping of blowflies

1. From collections of maggots from live sheep at Onderstepoort, Dohne, C.P. and the main sheep farming areas of the Union of South Africa, Lucilia cuprina alone was responsible for 55 per cent. of the total strikes, and in combination with other species the percentage was increased to 90. 2. Chrysomyia chloropyga, as a sheep myiasis producing fly, ranks next in importance to Lucilia cuprina. 3. From trapping records at Onderstepoort the seasonal abundance of blowflies are obtained. The necessity for using selective baits is stressed.The articles have been scanned in colour with a HP Scanjet 5590; 300dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format

A simple insect cage-olfactometer

The articles have been scanned in colour with a HP Scanjet 5590; 300dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format

Sheep blowfly research. V. Carcasses as sources of blowflies

1. The object of the investigation was to determine what species of flies bred in carcasses exposed under field conditions. 2. The technique of exposing sheep carcasses in specially constructed troughs and the collection of migrating larvae and the trapping of emerging flies are described. 3. Fly populations from small animal carcasses were bred at various times of the year. 4. The phenomenon of succession and competition of the inhabitants of carrion was demonstrated. 5. Lucilia cuprina, Lucilia sericata and Chrysomyia chloropyga mainly constituted the populations of flies bred during the cool time of the year, while Chrysomyia marginalis and Chrysomyia albiceps constituted the populations during mid-summer. 6. When Ch. marginalis is abundant it is attracted to carcasses in the first stage of decomposition. L. cuprina and L. sericata are usually the first visitors to fresh carcasses followed almost immediately by Ch. marginalis. 7. Certain suggestions are made for the treatment of carcasses as a means of controlling blowflies.The articles have been scanned in colour with a HP Scanjet 5590; 300dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format

Sheep blowfly research. III. Studies on the olfactory reactions of sheep blowflies

1. In a search for olfactory attractants to sheep blowflies, tests were conducted by means of an olfactometer in the laboratory, while some substances were tested under field conditions in traps. 2. Certain alcohols, aliphatic acids, esters, organic sulphides and inorganic salts were tested in the laboratory; boiled and unboiled solutions of sodium and potassium hydroxide were found to attract L. cuprina, while natural civet and musk ketone were weakly attractive. Sodium bicarbonate solution was repellent. Strong repellents are Dippel's oil, carvone, and linalool. 3. Preparations of suint were found in general to be unattractive. 4. The chemical treatment of meat bait by the addition of cystine, calcium carbonate, calcium sulphide, sodium carbonate, sodium sulphide and phenothiazine, enhanced its attractiveness. 5. Inoculation of meat bait with a mixed culture of bacteria from sheep's intestines increases attractiveness. 6. Fermenting baits, e.g., fish meal, pancreatin and egg, and addled eggs, proved to be attractive, but they were not so attractive as meat baits. 7. Some of the attractive substances of beef bait were extracted by ethyl ether, but these chemicals were not isolated or identified. A portion of these attractive substances were apparently removed from the ether solution by potassium hydroxide solution. 8. Flowers of Stapelia flavirostris are strongly attractive to, and stimulate oviposition by Lucilia cuprina. Distillates of these flowers were found to be attractive but no chemicals were isolated or identified. Further investigations on the chemistry of these flowers are recommended. 9. No blowfly attractant superior to chemically treated beef bait has been found.The articles have been scanned in colour with a HP Scanjet 5590; 300dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format

Sheep blowfly research. IV. Field tests with chemically treated carcasses

1. The pH of opened carcasses could not be controlled satisfactorily by dusting chemicals on them; but it is also very unlikely that better results will be obtained by the use of solutions of chemicals instead of powders. 2. In view of the above finding is was not found possible to maintain the pH of carcasses at a stage attractive to flies. 3. The attractiveness of carcasses and meat baits appears to depend on a number of factors, and also on the nature of any added chemical. The pH-level alone does not appear a sufficient criterion for attractiveness.The articles have been scanned in colour with a HP Scanjet 5590; 300dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format

Qualification of Programmable Electronic System (PES) equipment based on international nuclear I&C standards

Nuclear power plants (NPPs) are increasingly faced with the challenge of qualifying procured equipment, sub-components, and systems that contain digital programmed electronics for use in safety-related applications. Referred to as a "programmable electronic system" (PES), such equip