They occur only in tropical africa and are important as vectors of african trypanosomiasis in both humans and animals. General morphology glossina species are tan or brown flies, ranging in length from 6 to 14 mm, excluding the proboscis tubular mouthpart in invertebrates used for feeding. Animal trypanosomiasis an overview sciencedirect topics. Research open access the life cycle of trypanosoma. The parasite forms trypomastigotes in vertebrate hosts and epimastigotes in the insect vector. Microarchitecture of the tsetse fly proboscis parasites. It is caused by infection with protozoan parasites belonging to the genus trypanosoma. African trypanosomiasis also called sleeping sickness is caused by trypanosoma brucei, a unicellular parasitic protozoan. Morphemes are the smallest units in the structural analysis of words. Accordingly, current tsetse specification based on morphology may not be the only way to rapidly determine the species status of glossina spp. Tsetse flies study guide by mcka includes 20 questions covering vocabulary, terms and more. Tsetse fly genitalia article pdf available in ethology ecology and evolution 224. Trypanosoma brucei provides an excellent system for studies of many aspects of cell biology, including cell structure and morphology, organelle positioning, cell division and protein trafficking.
Pdf speciesspecific behavioral differences in tsetse fly genital. Tsetse flies genus glossina are large bloodsucking dipteran flies that are important as vectors of human and animal trypanosomiasis in subsaharan africa. Pdf distribution and abundance of tsetse flies glossina. Collectively, the morphology, the resonant properties and acoustic sensitivity of the tsetse prothorax are consistent with those of the tympanal hearing organs in ormia sp. Distribution of african sleeping sickness by country. Although tsetse flies feed mostly in daylight, feeding does occur at night. Just in front of the hypopygium is a plate bearing dark hairs called hectors. Dynamics of infection and competition between two strains of trypanosoma brucei brucei in the tsetse fly observed using fluorescent markers. Tsetse adults are most active in the morning and in the late afternoon. Zool 008 module nametitle protozoan module id m6 morphology, life cycle, mode of infection of trypanosoma keywords tsetse fly, trypanosomiasis, t. Glossina species are tan or brown flies, ranging in length from 6 to 14 mm, excluding the proboscis tubular mouthpart in invertebrates used for feeding. Introduction to morphology introduction to morphology.
The matrix assisted laser desorptionionisation time of flight mass spectrometry malditof ms is an established method of identification for microorganisms. The production of sound by several species of tsetse flies has been repeatedly documented. Both these structures make it easy to tell which flies are males see 8. The only known vector for each is the tsetse fly glossina spp. Scott department of biological sciences university of alberta supported in part by academic technologies for learning and faculty of science, university of alberta these modules are designed primarily for use in introductory entomology courses at the university of alberta. The tsetse fly is known for being the sole vector of the african trypanosomes trypanosoma brucei rhodesiense and t. A preliminary note on the morphology and distribution of the. They are transmitted to humans by tsetse fly glossina genus bites which have acquired their infection from human beings or from animals harbouring human. There are two separate subspecies which cause sleeping sickness in humans, trypanosoma brucei gambiense which accounts for around 98% of cases and trypanosoma brucei rhodesiense which accounts for the remaining 2% of cases. Examination of electron micrographs of flight muscles taken from flies subjected to enforced exercise, ormal exercise and no exercise reveals that both mitochondrial and myofibrillar fractions of the muscles are stimulated to grow at a faster rate by enforced exercise but that the mitochondria. A single female tsetse fly deposits 810 larvae, one at a time, at intervals of from 10 to 12 days each. In the flys midgut, the parasites transform into procyclic trypomastigotes, multiply by binary fission, leave the midgut, and transform into epimastigotes.
Sep 19, 2017 tsetse flies genus glossina are large bloodsucking dipteran flies that are important as vectors of human and animal trypanosomiasis in subsaharan africa. A preliminary note on the morphology and distribution of. Research open access the life cycle of trypanosoma nannomonas congolense in the tsetse fly lori peacock1,2, simon cook2,3, vanessa ferris1,2, mick bailey2 and wendy gibson1 abstract background. Zoology biology of parasitism morphology, life cycle, mode of infection of trypanosoma 2 description of module subject name zoology paper name biology of parasitism. Control control of african trypanosomiasis rests on two strategies. Symptoms include fatigue, high fever, headaches, and muscle aches. Quizlet flashcards, activities and games help you improve your grades.
Diagnosis is made by identifying parasites in specimens of blood, chancre fluid or tissue, lymph node aspirate, or cerebrospinal fluid. There are thirty named species and subspecies of tsetse flies all of which belong to the genus glossina. The life cycle of trypanosoma nannomonas congolense in. The developmental cell biology of trypanosoma brucei. The tsetsetransmitted african trypanosomes cause diseases of importance to the health of both humans and livestock. Tsetse adults are characterised by several distinctive morphological features. The site of the different trypanosome species in the fly is indicated in table 1. Glossina species are tan or brown flies, ranging in length from 6 to 14 mm, excluding the proboscis tubular mouthpart in invertebrates used. Thus 50 days elapse between the emergence of one female fly and the subsequent emergence of the first of its progeny. Tsetse biology, systematics and distribution, techniques. Morphometric characterization of three tsetse fly species. However, the trypanosome has a complex life cycle in which it must adapt either to the mammalian bloodstream or to different compartments within the tsetse fly.
These observations are the result of an inquiry entrusted to us by the tsetse fly committee of the royal society, at a meeting of the committee on march 16, 1899. Wild mammal populations increased rapidly, accompanied by the tsetse fly. Human african trypanosomiasis, also known as sleeping sickness, is a vectorborne parasitic disease. The third segment of the antenna bears an arista with hairs on the upper surface only which are themselves branched feathered. Sleeping sickness, as it is commonly called, is generally fatal in humans if left.
The most important vectors of human disease are glossina palpalis g. Pdf movements and morphology under sexual selection. The life cycle of trypanosoma nannomonas congolense in the. Buffycoat preparations concentrate the parasite, enabling easier visualization for diagnosis. The life cycle of trypanosoma brucei within the tsetse is one that is complex and spectacular. Trypanosomiasis, african sleeping sickness chapter 4. Domestic cattle are thought to be the most epidemiologicallyrelevant animal reservoir of t. Over a period of 1214 days it matures, mates and, if it is a female, deposits its first larva. The tsetsetransmitted african trypanosomes cause diseases of importance to the health of both. Nov, 20 the life cycle of trypanosoma nannomonas congolense in the tsetse fly. The life cycles of these trypanosomes in the fly were described in the last century, but comparatively few details are available for trypanosoma nannomonas congolense, despite the fact that it is probably the most prevalent and widespread pathogenic species for livestock in.
The proboscis also serves as the developmental site for the infective metacyclic. They can be divided into three distinct groups or subgenera. Geographic distribution of african trypanosomiasis by country 11 the distribution of african trypanosomiasis is completely linked to the range of its vector, the tsetse fly. This life cycle, with a slow reproductive rate and substantial parental investment in the care of young, is a relatively unusual example of an insect with a socalled ktype life history. African trypanosomiasis, also called african sleeping sickness, is a parasitic disease spread by the tsetse fly. Distribution and abundance of tsetse flies glossina spp. A preliminary note on the morphology and distribution of the organism found in the tsetse fly disease proceedings of the royal society of london. The sterile insect technique for control of tsetse flies in.
Observations of this species revealed otherwise cryptic, highly rhythmic and forceful thrusting, pinching, pressing, and scraping movements by the males genitalia within the females body that have no obvious relation to sperm transfer. Jun 27, 2012 the tsetse transmitted african trypanosomes cause diseases of importance to the health of both humans and livestock. The authors use a quantitative modelling framework to describe and explore the features of the biology of tsetse flies glossina spp. This slow rate of reproduction means that tsetse populations can be eradicated by killing just 23% of the female population per day. Large populations in april, 1998, continued as long as the high water caused streams to flow. The developing fourthstage larva is deposited in a shady spot, usually at the base of a tree or shrub, and immediately burrows into the soil and pupates. The life cycle of trypanosoma nannomonas congolense in the tsetse fly lori peacock1,2, simon cook2,3, vanessa ferris1,2, mick bailey2 and wendy gibson1 abstract background. Travelers who plan to spend a lot of time outdoors or. The adult fly emerges from the pupa in the ground after about 30 days. The sterile insect technique for control of tsetse flies. The life cycles of these trypanosomes in the fly were described in the last century, but comparatively few details are available for trypanosoma nannomonas congolense, despite the fact that it is probably the most prevalent and widespread pathogenic species for. They are transmitted to humans by tsetse fly glossina genus bites which have acquired.
They rarely fly more than 30 min a day and are known to disperse up to about 1 kmday. Pdf the life cycle of trypanosoma nannomonas congolense. Anderson department of zoology and comparative physiology, university of birmingham, p. Article pdf available in journal of animal ecology 553. Travelers who go to subsaharan africa are at risk see map. The tsetse fly becomes infected with bloodstream trypomastigotes when taking a blood meal on an infected mammalian host.
Tsetse anatomy has been well described, including detailed accounts of the functional anatomy of the proboscis for piercing host skin and sucking up blood. Humans are considered the main reservoir for trypanosoma brucei gambiense, but this species can also be found in animals, including primates and ungulates. Training manual food and agriculture organization of the united. Simuliidae 2 is variable, depending on the black fly species and water temperature. The palpalis and the morsitans group species are small to medium in size 6. The sterile insect technique for control of tsetse flies in africa by willem takken and michael weiss african trypanosomiasis and its major vector, the tsetse fly, have drawn worldwide attention due to the devasting effects they cause in large areas of tropical africa. Trypanosoma brucei this species causes sleeping sickness in humans and nagana in cattle.
Pdf a longstanding mystery in morphological evolution is why male. Highland regions of east africa which had been free of tsetse fly were colonised by the pest, accompanied by sleeping sickness, until then unknown in the area. There are about 30 known species and subspecies of tsetse. The tsetse transmitted african trypanosomes cause diseases of importance to the health of both humans and livestock. Tsetse sometimes spelled tzetze and also known as tiktik flies, are large biting flies that inhabit. Tsetse fly, genus glossina, any of about two to three dozen species of bloodsucking flies in the housefly family, muscidae order diptera, that occur only in africa and transmit sleeping sickness african trypanosomiasis in humans and a similar disease called nagana in domestic animals. Tsetse fly bites are characteristically painful, and a chancre may develop at the bite location. Glossinidae by gas chromatographic analysis of cuticular components volume 83 issue 4 d. Glossina tachinoides westwood was less closely related to others in the palpalis group than previously described using morphology. Arthropod vectors tsetse flies 2 page lateral aspect of the antenna of a tsetse fly both sexes are hematophagous.
The effect of exercise on the growth of mitochondria and. The effect of exercise on the growth of mitochondria and myofibrils in the flight muscles of the tsetse fly, glossina morsitans m. Millions of people died of the disease in the early 20th century. Exercise affects the growth of the dorsal longitudinal flight muscles in the tsetse fly. Blood stream forms trypomastigotes ingested by the fly undergo considerable changes, in morphology as well as in their metabolism. At first glance, it may be surprising why tsetse flies aren. The pan african trypanosomosis and tsetse eradication campaign pattec were borne. Due to the tsetse flys climatic restrictions the disease is restricted between the 14 th latitude north and the 29 th latitude south on the african continent. African animal trypanosomes food and agriculture organization. They are transmitted to humans by tsetse fly glossina genus bites which have acquired their infection from human beings or from animals harbouring human pathogenic parasites. The effect of the tsetse fly on african development pdf.
In the fly s midgut, the parasites transform into procyclic trypomastigotes, multiply by binary fission, leave the midgut, and transform into epimastigotes. Morphology is concerned with the internal structure of words and the rules for forming words from their subparts, which are called morphemes. When the male tsetse fly is looked at from the ventral side, a rounded structure can be seen at the posterior end of the abdomen. Here we will look at the morphology, life cycle, and spatial distribution of the tsetse fly and how these factors make it an ideal. Tsetse flies can detect odours by means of sensilla situated on the antennae. Every flowering plant providing food for one or many phytophagous insects.
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