Round Worms and Relatives

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Round Worms and Relatives
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Phylum Rotifera

• Ciliated crown looks like rotating wheels
• Shape and color many colors, shapes, some
  colonial
• Habitat fresh water, marine, terrestrial,
  parasitic (can survive dehydration)

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pHYLUM Nematodanemato meaning "thread"Roundworms

• General characteristics
• Habitat fresh water, soil, marine, parasitic
• Cylindrical shape
• Tegument (waxy coating)

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• Body wall
• Longitudinal muscles 4 cords
• Spindle that projects into pseudocoel
• Fluid acts as hydrostatic skeleton to provide
  leverage

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• Digestive system
• Mouth, pharynx, intestine, rectum, anus
• Food rotifers, small worms, plant juices, host
  tissue

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• Nervous system
• Ring of nervous tissue around pharynx
• 2 nerve cords (dorsal and ventral)
• Some sensory papillae (projections) on head

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• Excretory system
• One or more large gland cells or canal system
  (filter waste)
• Empty out excretory pore

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• Reproductive system most are dioecious
• Male (usually smaller than female) uses a special
  copulatory spine to open the females reproductive
  tracts and inject sperm
• Sperm are unique in that they lack flagella and
  move by pseudopodia, like amoebas
• Female fertilization is internal, eggs stored
  in uterus until laid

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Well Use Ascaris for the Reproduction
ExamplePicture Warning
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Ascaris intestinal roundworm
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Ascaris infections
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A pile of Ascaris worms that came from people
living in a small village in the south of India.
The worms will mainly came from children.
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Massive Ascaris infection. The worms are
expelled after medical treatment
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Life Cycle (Ascaris - The Large Roundworm in
Humans)

• Life cycle
• Egg - swallowed by host hatches
• Juveniles 4 stages of molting burrow through
  intestine
• Organs affected
• Veins
• Heart
• Lungs (trachea) cough/swallow
• Stomach
• About two months later intestine (adult worms)
• Female may lay 200,000 eggs a day, passing out in
  the hosts feces
• Boys tend to be more heavily affected than
  females presumably because boys are more likely
  to eat dirt than girls.

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• Symptoms
• Nausea, vomiting, intestinal cramping,
• Wandering worms
• Emerge from anus, throat, eustachian tubes (ears)

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Hookworms
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Hookworm
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Hookworms

• Size and shape 9-11mm
• Body form large plates in mouth to cut
  intestine of host and suck blood
• Human symptoms
• Anemia (lack of RBCs)
• In children
• Mental retardation
• Stunted growth

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Hookworms

• Life cycle
• Eggs feces, hatch in soil
• Larvae feed on bacteria
• Organs affected
• Blood
• Lungs (cough and swallow)
• intestine
• Prevention
• Wear shoes

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Trichina worm a pork infesting parasite

• Life cycle
• Burrows into intestine
• Female produces live young
• Organs affected
• Blood vessels
• Skeletal muscle cyst
• intestine
• Prevention
• Cook pork thoroughly!

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Pinworms

• The most common worm infection in the US
• Common in young children
• FYI spread from child to child on clothing,
  bedding toys then they put their fingers in
  their mouth

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Pinworms

• Life cycle
• adults live in large intestine
• Female migrate to outside the anus (at night) to
  lay eggs
• Symptoms
• Itchiness around anus
• Restless sleep
• Irritability
• Loss of appetite
• Many affected people have no symptoms

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Pinworms

• Prevention
• Wash hands frequently
• Keep your child's fingernails trimmed
• Discourage your child from nail-biting and
  putting things in his/her mouth
• Make sure your child wears clean underwear

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Filiarial worms

• Tropical countries
• Symptoms
• Obstruct lymph vessels
• FYI quick review on the lymphatic system
• The lymphatic system is like the blood
  circulation
• tubes branch through all parts of the body LIKE
  the arteries and veins that carry blood EXCEPT
  that the lymphatic system carries a colorless
  liquid called 'lymph'.
• Lymph is a clear fluid that circulates around the
  body tissues. It contains a high number of WBCs.
  Plasma leaks out of the capillaries to surround
  and bathe the body tissues. This then drains into
  the lymph vessels.

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Filarial Worms

• Creates long excessive growth of connective
  tissue
• Picture Warning

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Filarial Worm - Elephantitis
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(No Transcript)
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Filarial Worms

• Prevention
• Take preventative medications (DEC
  diethylcarbamazine) when traveling
• Avoid mosquito bites (mosquitoes serve as
  vectors)
• Live somewhere else!!!!

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Toxacara canis(canine roundworm)

• Life cycle
• Worms in feces or soil (can stay there for years)
  
• In dog can travel to eye scar, blind, migrate
  to liver or spleen
• Humans can be infected with this worm
• FYI They are extremely resistant to adverse
• environmental conditions once an area is
• contaminated with eggs (playground, park,
• back yard) it is difficult to sanitize the area

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DUSNDiuffuse Unilateral Subacute Neuroretinitis

• Carried by raccoons, enters through broken
  skin, eating contaminated food
• Symptoms attacks retina, ocular migraines
• Prevention avoid raccoons

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Guinea Worm

• Life cycle ( 1 year)
• Juveniles in water
• carried by small crustacean (copeopods)
• ingested when drinking
• Reproduce, male dies
• Female migrates to skin (usually legs, ankles, or
  feet)
• produces juveniles
• Blister formsJuveniles are liberated to the
  water
• Symptoms
• large painful water filled blister, worm under
  skin
• Prevention
• Drink clean water

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Guinea WormPictures
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Guinea worm
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Guinea worm fiery serpent
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Guinea worm