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[Help with translations!] HematophagyFrom Wikipedia, the free encyclopediaJump to: navigation, search
An Anopheles stephensi mosquito obtaining a blood meal from a human host through its pointed proboscis. Note the droplet of blood being expelled from
the abdomen after having engorged itself on its host’s blood. This mosquito is a malarial vector with a distribution that ranges from Egypt to
Butterflies sucking fresh blood from a sock"Bloodsucker" redirects here. For other uses, see Bloodsucker (disambiguation).
Hematophagy (sometimes spelled haematophagy or hematophagia) is the practice of certain animals of feeding on blood (from the Greek words, haima
"blood" and phagein "to eat"). Since blood is a fluid tissue rich in nutritious proteins and lipids that can be taken without enormous effort,
hematophagy has evolved as a preferred form of feeding in many small animals such as worms and arthropods. Some intestinal nematodes, such as
Ancylostomids, feed on blood extracted from the capillaries of the gut and about 75% of all species of leeches (e.g. Hirudo medicinalis),[citation
needed] a free-living worm, are hematophagous. Some fish, such as lampreys, and mammals, especially the vampire bats, also practice hematophagy.
1 Mechanism and evolution
2 Medical importance
3 Human hematophagy
4 See also
6 External links
 Mechanism and evolutionThese hematophagous animals have mouth parts and chemical agents for penetrating vascular structures in the skin of
hosts, mostly of mammals, birds, and fish. This type of feeding is known as phlebotomy (from the Greek words, phleps "vein" and tomos
Once phlebotomy is performed (in most insects by a specialized fine hollow "needle" called proboscis which perforates skin and capillaries; in bats
by sharp incisor teeth that act as a razor to cut the skin), blood is acquired either by sucking action directly from the vases, from a pool of
escaped blood, or by lapping (again, in bats). In order to overcome natural hemostasis (blood coagulation), vasoconstriction, inflammation, and pain
sensation in the host, biochemical solutions in the saliva for instance, for pre-injection, anesthesia and capillary dilation have evolved in
different hematophagous species. Anticoagulant medicines have been developed on the basis of substances found in the saliva of several hematophagous
species such as leeches (hirudin).
Hematophagy can be classified into obligatory and optional practice. Obligatory hematophagous animals do not have any other type of food besides
blood; one such species is Rhodnius prolixus (an assassin bug from South America). This contrasts with optional hematophages, like the many mosquitoes
species, such as Aedes aegypti, which may also feed on pollen, fruit juice, and other biological fluids. Sometimes only the female of the species is a
hematophage (this is essential for egg production and reproduction). Coyotes, wolves, and other canids may lick blood.
Hematophagy has apparently evolved independently in many disparate arthropod, annelid, nematode and mammalian taxa. For example Diptera (insects with
two wings, such as flies) have eleven families with hematophagous habits (more than half of the 19 hematophagous arthropod taxa). About 14,000 species
of arthropods are hematophagous, even including some genera that were not previously thought to be, such as moths of the genus Calyptra. Several
complementary biological adaptations for locating the hosts (usually in the dark, as most hematophagous species are nocturnal and silent, in order to
avoid detection and destruction by the host) have also evolved, such as special physical or chemical detectors (for sweat components, CO2, heat,
light, movement, etc.).
 Medical importanceThe phlebotomic action opens a channel for contamination of the host species with bacteria, viruses and blood-borne parasites
contained in the hematophagous organism. Thus, many animal and human infectious diseases are transmitted by hematophagous species, such as the bubonic
plague, Chagas disease, dengue fever, filariasis, leishmaniasis, Lyme disease, malaria, rabies, sleeping sickness, St. Louis encephalitis, tularemia,
typhus, Rocky Mountain spotted fever, West Nile fever, and many others.
Insects and arachnids of medical importance for being hematophagous, at least in some species, include the sandfly, blackfly, tsetse fly, bedbug,
assassin bug, mosquito, tick, louse, mite, midge, and flea.
Hematophagous organisms have been used by physicians for beneficial purposes (hirudotherapy). Some doctors now use leeches to prevent the clotting of
blood on some wounds following surgery or trauma. The anticoagulants in the laboratory-raised leeches' saliva keeps fresh blood
flowing to the site of an injury, actually preventing infection and increasing chances of full recovery. In a recent study a genetically engineered
drug called desmoteplase based on the saliva of Desmodus rotundus (the vampire bat) was shown to improve stroke patients.
 Human hematophagyMain article: Blood as food
Drinking blood and manufacturing foodstuffs and delicacies with animal blood is also a feeding behavior in many societies. Cow blood mixed with milk,
for example, is a mainstay food of the African Maasai. Some sources say that Mongols would drink blood from one of their horses if it
became a necessity. Black pudding is eaten in many places around the world. Some societies, such as the Moche, had ritual hematophagy, as well as the
Scythians, a nomadic people of Russia, who had the habit of drinking the blood of the first enemy they would kill in battle. Some religious rituals
and symbols seemingly mirror hematophagy, such as in the transubstantiation of wine as the blood of Jesus Christ during Christian eucharist.
Psychiatric cases of patients performing hematophagy also exist. Sucking or licking one's own blood from a wound is also a behavior commonly seen in
humans, and in small enough quantities is not considered taboo. Finally, human vampirism has been a persistent object of literary and cultural
 See alsoConsumer-resource systems
 ReferencesScharfetter C, Hagenbuchner K (1967). "Blutdurst als Symptom. Ein seltsamer Fall von Bluttrinken". Psychiatr Neurol (Basel) 154
Ciprandi A, Horn F, Termignoni C (2003). "Saliva of hematophagous animals: source of new anticoagulants" (PDF). Rev. Bras. Hematol. Hemoter. 25 (4):
Markwardt F (October 2002). "Hirudin as alternative anticoagulant--a historical review". Semin. Thromb. Hemost. 28 (5): 405–14.
doi:10.1055/s-2002-35292. PMID 12420235. www.thieme-connect.com...
Ribeiro JM (September 1995). "Blood-feeding arthropods: live syringes or invertebrate pharmacologists?". Infect Agents Dis 4 (3): 143–52. PMID
 External links Look up bloodsucker in Wiktionary, the free dictionary.
Schutt, W. A website dedicated to the study of blood feeding creatures
Galun, R. Evolution of Hematophagy
Beaty, LC. Host-Seeking Behavior in Hematophagous Mosquitoes
[hide]v · d · eFeeding behaviours
Carnivores adult Hematophagy · Insectivore · Lepidophagy · Man-eater · Molluscivore · Mucophagy · Myrmecophagy · Ophiophagy · Piscivore ·
Avivore · Spongivore · Vermivore · Herpetivore
reproductive Oophagy · Ovophagy · Paedophagy · Placentophagy · Breastfeeding · Weaning
cannibalistic Cannibalism · Human cannibalism · Self-cannibalism · Sexual cannibalism
Herbivores Folivore · Frugivore · Graminivore · Granivore · Nectarivore · Palynivore · Xylophagy · Osteophagy
Others Phagocytosis · Bacterivore · Coprophagia · Detritivore · Fungivore · Geophagy · Omnivore
Methods Apex predator · Bait balls · Bottom feeding · Browsing · Feeding frenzy · Filter feeding · Grazing · Hypercarnivore • Intraguild
predation · Kleptoparasitism · Scavenging · Trophallaxis
Predation · Antipredator adaptation · Carnivorous plant · Carnivorous fungus · Carnivorous protist · Category:Eating behaviors
Therefore imho it is possible that a group of humans have evolved to be specialistic Hematophagic behaviour.