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Explore the world of insects' role in food hygiene, their diverse diets, and transmission of pathogens. Learn about common species like houseflies and mosquitoes and their impact on human health.
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Insects Relevant in food hygiene An overview
Most specious-rich class in the animal kingdom • 1 Mio. insects described (realistic: between 1 Mio. and 80 Mio.) • Central Europe: 40,000 insect species • Polymorphic class: • Size: a few tenth of a millimetre up to 30 cm wing span • With wings or wingless • Unobtrusive colouring to striking patterns General Characteristics
Pronounced segmentation • Head (Caput) • Thorax • Abdomen • Exoskeleton made of chitin • Body surface is water and gas impermeable; prevents dehydration and protects from mechanical and chemical impacts Body Plan
Metamorphosis • Imperfect • Complete Life Cycle Oviposition Larvae Imago (Adult) Puppae
Herbivore / Phytophagous insects • E.g.: butterflies, sawflies, bees... • Wood eater / Xylophagous insects • E.g.: bark beetle, wood drill, termites, horntail • Gall makers / Cecidozoa • E.g.: gall wasp, gall mite, weevil... Insect Diet
Feeding on dung / Coprophagic insects • E.g.: dung beetle, dung fly... • Predator / Entomophagous insects • E.g.: dragonfly, bug... • Parasites • E.g.: mosquitos, bed bugs, fleas, lice • Transmission of pathogens Insect Diet
Insects since approx. 500 million years • Colonisation of a variety of habitats • Humans since approx. 2 million years • Useful insects: honey bee, silk moth... • Transmission of pathogens • Adaptation of insects to the human lifestyle • Food stuff, commodities & garbage Humans & Insects
Virus • Yellow fever via mosquitos • Dengue fever via mosquitos • Bacteria • Dysentery via flies • Typhus via lice and fleas • Pest via fleas • Plasmodia • Malaria via Anopheles mosquitos • Flagellates • Sleeping sickness via tsetse fly Transmission of Pathogens
Attracted by food and waste smells Transmission of pathogens for cholera and amoebic dysentery World occurance Oviposition in manure and garbage One fly lies 500 eggs in 3 weeks Housefly – Musca domestica Sighting (pink): J F M A M J J A S O N D
Tiny flies (1-6 mm) Attracted by putrescent smells, left-overs More than 3000 species worldwide Most famous: Drosophila melanogaster – Model organism of geneticists Fruit Flies - Drosophilidae
Similar to housefly, but with forward-facing proboscis World occurrence; close to stables Food: Males & females suck blood of warm-blooded animals Oviposition in dung Stable Fly – Stomoxyscalcitrans J F M A M J J A S O N D
Occurrence in entire Europe; houses close to food stuff Attracted by smell of raw meet Oviposition on raw meet Transmission of bacteria, fungi, viruses Grey Flesh Fly – Sarcophagacarnaria J F M A M J J A S O N D
World occurrence Can smell fresh cadaver over distance of 10 km (forensic entomology) Oviposition on cadaver and open wounds Blue Meat Fly – Calliphora vicina J F M A M J J A S O N D
Very large (20-25 mm), dipterous fly with large green striped and iridescent compound eyes Occurrence: Europe to Southern Scandinavia, Middle East and Northern Africa; always close to waters Food: Females suck blood of warm-blooded animals (cattle); males visit flowers Horse-fly bites are painful Pale giant Horse Fly – Tabanusbovinus J F M A M J J A S O N D
Size: 6-7 mm Occurrence: worldwide, close to fresh water, brackwater, in swamps or meadows Food: Females are dependent on blood of warm-blooded animals Reproduction: Oviposition in spring in waters The malaria mosquito (Anopheles) appears increasingly in Europe Mosquito – Culex pipiens J F M A M J J A S O N D
Originally home to southern and south-east tropics Since the 1990s spreading in Europe (globalisation, climate change) Transmission of Chikungunya- and Dengue fever Striking patterning Asian Tiger Mosquito – Stegomyiaalbopicta
Wasps are attracted by sugary syrups and feed on fruits and sweets All wasps contain a poison sting Wasp – Vespula vulgaris J F M A M J J A S O N D
Occurrence from Europe to Asia Size: 18-35 mm Less obtrusive and harmful than wasps Sting is painful but not more serious than that of a wasp Hornets prey on insects and small animals Hornet – Vespa crabro J F M A M J J A S O N D
Allergic reaction to insect poisons Sting by wasps, honeybees; also hornets and humble bees Potentially lethal Insect Poison Allergy
http://www.insektenbox.de/index.html GU Naturführer Insekten & Schmetterlinge http://de.wikipedia.org/wiki/Asiatische_Tigerm%C3%BCcke References