Lab 7 -Slide Observation of Adult Mosquito- Subfamily: Anophelinae &Culicinae Title: Differentiate Of Male And Female Mosquitos:Family Culicidae

Lab 7 -Slide Observation of Adult Mosquito- Subfamily: Anophelinae &Culicinae

Title: Differentiate Of Male And Female Mosquitos:Family Culicidae

Introduction

The distribution of the mosquito is worldwide, it were occur the tropical and temperature regions. It were absent on Antarctica and a few island, it can be up to 3500m and down 1250m sea level, the mosquito family have three family toxorhynchitinae,anophelinae and culicinae.the most important pest and vector species belong to the genera anopheles ,culex,aedes,ochlerotatus,psorophora and sabethes .the mosquito is the bloodsucking insect that responsible to the many type of diseases in the world. it also as the vector.

Objective:

1.    To differentiate the general morphology of adult between male and female

2.    To identify the external morphology that differentiate between male and female mosquito belonging to the subfamily anophelinae

3.    To identify the external morphology that differentiate between male and female mosquito belongings to the family culicinae

Methodology:

1.    Observed the slide male and female mosquito in the subfamily anophelinae

2.    Observed the slide male and female mosquito belongings to the subfamily culicinae

Discussion

 The antennae are plumose in male and pilose in the female.Adult size 1.6-12.5 mm in length. Divided into head, thorax, and abdomen. The head is sub globose, with a pair of antennae, compound eyes, maxillary palpi, and one proboscis. Thorax is divided into pro, meso, and metathorax. The mesothorax is well developed, with a pair of wings. One pair of legs on each thoracic segment. A pair of halteres on metathorax.. Abdomen is composed of 10 segments, 8 visible, the last 2 modified to form genital organs, 7 pairs of spiracles on the anterior 7 segments.

The head of the mosquito have maxilla, hypo pharnrynx ,labellum,labium,labrum and mandible. The proboscis is used to the blood sucking on the skin; The antennae are an insects primary, non-visual, sense organs, though in a few rare instances they have become adapted for other purposes.

Mosquito are slender ,delicate flies that are generally less than 6mm long, they have sucking proboscious the distinguish them from gnat and midget. Only female bite and suck blood, male can draw blood and nectar and fruit juice. Female have plain antenna because they have no need for the more elaborated antenna that males use to find female. The female find warm blooded animal by following trails of exhaled carbon dioxide. Mosquito need find standing water in which to lay egg thus abundant in wet seasons and perpetually humid climate.

Mosquitoes are relatively small insects, measuring an average of just more than 6 mm long and weighing about 2.5 milligrams. They're divided into three basic parts: the head, thorax and abdomen. The head is crammed with sensory equipment that help the mosquitoes find and feed on people and animals.

They have two large compound eyes covered with tiny lenses called ommatidia that are capable of detecting even slight movement. On the top of their heads, they also have ocelli, simple photosensitive eyes detect variations in light. Their antennae, long feathery organs, jut forward from their heads and contain sensitive receptors that detect carbon dioxide in human breath from distances of more than 100 feet. The maxillary palp between the antennae picks up the odor of ocentol and other chemicals released in human sweat.

Right in the middle, also between the antennae, is the proboscis, a long serrated mouthpart used to pierce the skin and suck out blood. The proboscis holds two tubes, one that injects saliva containing an anti-coagulant and mild painkiller, and a second that actually draws the blood. The thorax, or what you might think of as the torso, is connected to the head. A pair of wings and a pair of halters, small wing-like organs used for steering, sprout from the thorax. The legs also come out of the thorax, six in all, with tiny claws at the end of each to help the mosquitoes stay attached to surfaces.

The abdomen hangs from the thorax and serves as the mosquitoes' stomach and lungs. Small openings called spiracles line both sides of the abdomen, allowing the mosquitoes to draw in air. The abdomen holds the blood that female mosquitoes take in, and a nerve in the abdomen signals when it is full. A female's eggs are also stored in the abdomen. Scientists use small differences in the shape and coloring of the abdomen, as well as in the length of the maxillary palp and wings, to identify the various species of mosquito.

The antenna of the male and female not same the male is bushier than female. The antenna of the male is long than proboscios the male culicinae is tip not club-shaped and tip club shaped for male anophelinae.the female palp is short, but the male are long palp.

The palps in both sexes are as long, or nearly as long, as the proboscis. The scutellum is rounded. Wings of nearly all species have characteristic patterns of pale and dark spots of scales .The subfamily Anophelinae was divided by Edwards into three genera: Chagasia (scutellum slightly trilobed), Bironella (scutellum evenly rounded, wing with stem of median fork wavy) and Anopheles (scutellum evenly rounded, wing with stem of median fork straight). The genus includes more than 400 species. When settled, most Anopheles stand with the proboscis, head and abdomen in almost a straight line, usually resting on an upright surface at an angle of about 45°; exceptionally, as in A. culicifacies, the resting position adopted is more Culex-like .In flight the hum produced by Anophelesis low pitched, almost inaudible unless close to the ear. Most species require large spaces for mating flights, rendering it difficult to propagate them in captivity.

This large and heterogeneous subfamily of mosquitoes contains over 2500 species and some 30 genera. The scutellum is trilobed, each lobe bearing bristles. The abdomen is blunt and completely clothed with broad flat scales. The eighth segment of the larva bears a patch of comb teeth on each side, used for cleaning the mouth brushes, and is drawn out into a respiratory siphon, with well developed pecten teeth in a row on each side. There are no abdominal palmate hairs (cf. Anopheles). Below the siphon the anal segment of the larva bears a chitinous saddle, four gills, caudal setae and the ventral brush for swimming. Culicine pupae are similar to those of Anopheles, but the respiratory trumpets are not so flared distally.

The HIV virus cannot be transfer by mosquito by the sucking of the blood from infected people to non infected people.

Conclusion

The morphology of male and female is different from each other also the subfamily is also different from each other.

Questions:

1.    Describe the difference between the subfamily of Culicinae and Anophelinae

The palp of the culicinae is tip not club-shaped and the anophelinae is tip club-shaped,the culicinae abdomen are covered dorvasally and ventrally brown ,blackish,whitish scales but the anophelinae abdomen almost,entirely devoid scales.

2.    Is it true that mosquito highly attracted to ABO grouping ‘O’ compare to other blood type?

Mosquitoes were more likely to bite people with type O blood than other potential victims, while people with type A got the fewest bites. This phenomenon, claiming that factors such as sweatiness are more likely to influence victim selection. They found type O secretors were twice as attractive to mosquitoes as type A secretors. Scientific studies point to the fact that mosquitoes are attracted to the carbon dioxide in the air that mammals exhale. 

References

• http://www.cabdirect.org/abstracts/19900500960.html;jsessionid=53B1B1661DBC5EDB31A1095B37F1BCC1
• http://usgs.wildlifeinformation.org/s/0zAMand_Hexapod/Dipt_Culi_Culex/Culex_quinquefasciatus.html
•  

Practical 6 Slide Observation of Order Siphontera And Acarina Title: Slide Ctenocephalides Spp. And Ixodes

Practical 6

Slide Observation of Order Siphontera And Acarina

Title: Slide Ctenocephalides Spp. And Ixodes

Introduction

Ixodes is a genus of hard-bodied ticks (family Ixodidae). It includes important disease vectors of animals and humans (tick-borne disease). Some ticks in this genus may transmit the pathogenic bacterium Borrelia burgdorferi responsible for causing Lyme disease. Additional organisms that may be transmitted by Ixodes are parasites from the genus Babesia which cause babesiosis, and bacteria from the related genera Ehrlichia which cause ehrlichiosis and Anaplasma which cause anaplasmosis.

Flea is the common name for insects of the order Siphonaptera which are wingless insects with mouthparts adapted for piercing skin and sucking blood. Fleas are external parasites, living by hematophagy off the blood of mammals (including bats and humans) and birds.

Objectives

To identify the external morphology that differentiate between the genus (genal comb,meral rod and pronotal comb)

Methodology

Slide observation of the ctenocephalides spp and ixodase

Discussion

Fleas are small, agile, usually dark colored, wingless insects with tube-like mouth-parts adapted to feeding on the blood of their hosts. Their legs are long, the hind pair well adapted for jumping: a flea can jump vertically up to 7 inches (18 cm) and horizontally up to 13 inches (33 cm)..It has been known that fleas do not use muscle power but energy stored in a protein named resilin. Their bodies are laterally compressed (human anatomical terms), permitting easy movement through the hairs or feathers on the host's body (or in the case of humans, under clothing).

The flea body is hard, polished, and covered with many hairs and short spines directed backward^, which also assist its movements on the host. The glossy surface of the body allows easy movement through hair and feathers .The tough body is able to withstand great pressure, likely an adaptation to survive attempts to eliminate them by mashing or scratching.

Fleas lay tiny white oval-shaped eggs better viewed through a loupe. The larva is small, pale, has bristles covering its worm-like body, lacks eyes, and has mouthparts adapted to chewing. The larvae feed on various organic matters, especially the feces of mature fleas. The adult flea's diet consists solely of fresh blood    in the pupal phase; the larva is enclosed in a silken, debris-covered cocoon. Compound eyes are absent, but some species have large or small simple eyes.

The head of Ctenocephalides sp is rounded on its upper and anterior surface. Ctenocephalide canis, the dog flea, has a sharp curve here; Ctenocephalides felis felis, the cat flea, has a shallow curve. Ctenocephalides canis usually has three or four setae on the metepisternum; the others species usually have only one or two.

Fleas (order Siphonaptera) are one of the major groups of blood-sucking insects. They belong to holometabolic insects. Holometabolism is a feature characteristic also of Diptera, Lepidoptera, etc. Fleas form a separate well differentiated order,

Adult fleas are obligatory hematophages parasitising warm-blooded animals - mammals and birds. Wormlike free-living legless flea larva develops in the litter of host's nest. The majority of fleas are periodically attacking burrow or nest-dwelling parasites, capable of long time to present in host’s fur, unlike free blood-suckers, such as, for example, Diptera or some bugs.

Acari (or Acarina) are a taxon of arachnids that contains mites and ticks.Most acarines are small .Mites are arachnids and, as such, should have a segmented body with the segments organised into two tagmata: a prosoma (cephalothorax) and an opisthosoma (abdomen). This anterior body region is called the capitulum. The remainder of the body is called the idiosoma and is unique to mites.

Most adult mites have four pairs of legs, like other arachnids, but some have fewer.Larval and prelarval stages have a maximum of three pairs of legs; adult mites with only three pairs of legs may be called 'larviform'.

The mouth parts of mites may be adapted for biting, stinging, sawing or sucking. They breathe through tracheae, stigmata (small openings of the skin), intestines and the skin itself. Species hunting for other mites have very acute senses, but many mites are eyeless. The central eyes of arachnids are always missing, or they are fused into a single eye. Thus, any eye number from none to five may occur.

Conclusion

The morphology of the ctenocephalides and ixodase are different between each other and the observation of it were observed

References

http://entnemdept.ufl.edu/creatures/urban/medical/deer_tick.htm

http://en.wikipedia.org/wiki/Ixodes_scapularis

Question

1.    State the species name of human flea.

Pulex irritans

2.    What is the possible disease that can be transmitted by Ixodes.

Lyme disease, babesiosis and anaplasmosis.

3.    Classify the types of life cycle of Ctenocephalides and Ixodes

Ixodase -Hemimetabolism

Ctenocephalides-holometabolous

Practical 5 SLIDE PREPARATION OF MOSQUITO LARVAL – MALAYSIAN SPECIES Title: Mosquito larva collection, identification and processing.

Practical 5

SLIDE PREPARATION OF MOSQUITO LARVAL – MALAYSIAN SPECIES

Title: Mosquito larva collection, identification and processing.

Introduction

There are many type of the mosquito that exist on the world, the common infect human and give diseases are the aedes ,culex mansoni,and anopheles. Mosquitoes go through four stages in their life-cycle: egg, larva, pupa, and adult. Adult females lay their eggs in standing water, which can be a salt-marsh, a lake, a puddle, a natural reservoir on a plant, or an artificial water container such as a plastic bucket. The first three stages are aquatic and last 5–14 days, depending on the species and the ambient temperature; eggs hatch to become larvae, then pupae. The adult mosquito emerges from the pupa as it floats at the water surface. Adults live for 4–8 weeks. Male eat nectar and female feed blood.

Objective:

1.    To understand the purpose and method of larva processing.

2.    To identify the function of each reagent.

3.    To identify the processing procedure.

4.    To identify the morphology of mosquito larva.

5.    To differentiate morphology of Anophelinae and Culicinae larva.

Materials:

Water bath (37^oc), acid acetic 10%, Kalium hydroxide 2%, alcohol solution (30%, 50%, 70%, 90% and 100%), xylene, clove oil, mounting DPX, stereozoom microscope, needle, glass slide, section lifter, dissecting pin, cavity block.

Procedure:

1.    Mosquito larva was collected from various water sources.

2.    The mosquito larva collected was killed in waterbath (37^oc).

3.    The thorax of the larva was penetrated using fine needle.

4.    The larva was place in 2% KOH and left it to room temperature until the larva become clear (2-4 hours).

5.    The larva was rinsed two times with distilled water and immersed in 10% acid acetic for 30 minutes.

6.    The preservation method was performed as the following:

a)    The sample was immersed in 70% alcohol to kill the insect.

b)    Soaked in KOH for at least 30 minutes.

c)    Rinsed with distilled water.

d)    Dipped in the following alcohol for 30 minutes each; 30%, 50%, 70%, 90%, 100%, 100%

e)    Next, in clove oil and finally in Xylene.

f)     After that, the larva was placed on slide and DPX was dropped.

g)    The cover slip was used to cover.

7.    The slide was observed under microscope.

8.    The observation was recorded and identified the family of mosquito larva observed.

Discussion

In the preparation of the larva slide the larva that has been taken will be immersed in certain alcohol for some purpose, it were used to as the preservative to the larva. The alcohol used are  30%, 50%, 70%, 90%, 100%, 100% alcohol.it also make the larva are death ,by doing the preservation it can make the larva can be maintain it shape for long time.it also make the larva are not effect by the mold or dust that damaged the slide for the observation,it also make the larva can be maintain it shape without damaged the shape morphology,if we use the big insect we will insert some cotton inside it body to maintain it shape.the changes of the concentration are to ensure the enzyme inside the larva removed also the other substances.it also the factor to maintain the structure of the larva for long period.

The female aedes mosquito bites as it needs the protein in blood to develop its eggs.The mosquito becomes infective approximately 7 days after it has bitten a person carrying the virus. This is the extrinsic incubation period, during which time the virus replicates in the mosquito and reaches the salivary glands.Peak biting is at dawn and dusk.the average lifespan of an Aedes mosquito in Nature is 2 weeks.The mosquito can lay eggs about 3 times in its lifetime, and about 100 eggs are produced each time.The eggs can lie dormant in dry conditions for up to about 9 months, after which they can hatch if exposed to favourable conditions, i.e. water and food.the identification of the aedes are know by the leg that it have that is the striated the black and white. Aedes aegypti is a vector for transmitting several tropical fevers. Only the female bites for blood which she needs to mature her eggs. Understanding how the mosquito detects its host is a crucial step in the spread of the disease. Aedes aegypti are attracted to chemical compounds that are emitted by mammals. These compounds include ammonia, carbon dioxide, lactic acid, and octenol. 

The culex Eggs of these mosquitoes, typically for culicines, are laid singly or in rafts and although they may stick to the surface, they may sink if the water is disturbed. Culex prefers water contaminated with organic matter for the development of the larvae and in will grow well in septic tanks.Disease is spread by females. Males do not bite. The females take blood meals that are used to support the development of eggs. Culex is described as zoophagic because it takes its meals from animals as well as humans and can also be described as ornithophagic because it frequently feeds on birds. Any disease that is carried by Culex can therefore become difficult to eradicate because any animal community that it feeds on can become a reservoir and mobile species, such as birds, can spread the disease through a large area. This was seen in 1999 in the Eastern United States when West Nile virus was introduced into the area. Culex pipiens feeds at night.Feeding is described as endophagic because the mosquito prefers to feed in and around structures and the mosquito then rests in cool damp spots within structures while the meal is digested (endophilic behavior). A blood meal takes 2-7 days to digest and 1-3 meals are needed to complete development of clutch of eggs. Transmission comes from repeated biting when the mosquito injects saliva that acts as an anticoagulant.

The mansonia  is A genus of brown or black medium-sized mosquitoes ,often with banded abdomen and legs; larvae and pupae have modified breathing tubes enabling them to pierce aquatic plants to obtain air. Mansonia mosquitoes are distributed worldwide and, in tropical areas, are important vectors of Brugia malayi; in some areas they also transmit Wuchereria bancrofti. Adults of Mansonia are generally large mosquitoes characterised by the presence of broad, asymmetrical scales on the wing veins. There is often a mixture of dark and pale scales that imparts a speckled appearance to the wings.Mansonia resemble some species of Culex, Aedini and Coquillettidia, but the tarsal claws are simple, the abdomen is truncate in females (distinctions from aedine genera),  The larvae of Mansonia resemble those of Coquillettidia in having the spiracular apparatus and siphon distinctively modified for piercing plant tissues. They differ from Coquillettidia in having the distal part of the antenna fused with and much shorter than the basal part.

The Anopheles mosquitoes can be distinguished from other mosquitoes by the palps, which are as long as the proboscis, and by the presence of discrete blocks of black and white scales on the wings. Adult Anopheles can also be identified by their typical resting position: males and females rest with their abdomens sticking up in the air rather than parallel to the surface on which they are resting. The abdomen is specialized for food digestion and egg development. This segmented body part expands considerably when a female takes a blood meal. The blood is digested over time serving as a source of protein for the production of eggs, which gradually fill the abdomen. The duration from egg to adult varies considerably among species and is strongly influenced by ambient temperature. Mosquitoes can develop from egg to adult in as little as 5 days but usually take 10–14 days in tropical conditions.

Like all mosquitoes, adult Anopheles have slender bodies with 3 sections: head, thorax and abdomen.The head is specialized for acquiring sensory information and for feeding. The head contains the eyes and a pair of long, many-segmented antennae. The antennae are important for detecting host odors as well as odors of breeding sites where females lay eggs. The head also has an elongated, forward-projecting proboscis used for feeding, and two sensory palps.

Most Anopheles mosquitoes are crepuscular (active at dusk or dawn) or nocturnal (active at night). Some Anopheles mosquitoes feed indoors (endophagic) while others feed outdoors (exophagic). After feeding, some blood mosquitoes prefer to rest indoors (endophilic) while others prefer to rest outdoors (exophilic), though this can differ regionally based on local vector ecotype, and vector chromosomal makeup, as well as housing type and local microclimatic conditions. Biting by nocturnal, endophagic Anopheles mosquitoes can be markedly reduced through the use of insecticide-treated bed nets (ITNs) or through improved housing construction to prevent mosquito entry (e.g. window screens). Endophilic mosquitoes are readily controlled by indoor spraying of residual insecticides. In contrast, exophagic/exophilic vectors are best controlled through source reduction (destruction of the breeding sites).

The female mosquito lays 30-150 eggs every 2-3 days. Human blood is needed to nourish these eggs and Anopheles shows the most regular cycles of blood feeding and egg laying. As a corollary, by using personal protective measures against mosquito bites, like using mosquito nets, one can deny the blood meal and hence help in mosquito control.

Conclusions

The larva preservation and the making slide of it were made and the morphology of the larva was observed and drew.

Question

Describe the function of the following solution

Potassium hydroxide-it makes the larva flatted and maintains the appearances

Clove oil-it act as the anesthetic

References

·         http://mosquito-taxonomic-inventory.info/genus-emmansoniaem-blanchard-1901

·         http://www.righthealth.com/topic/anopheles/Guides-and-Articles