Exam 2 Parasites Flashcards
Describe Entamoeba gingivalis
-First Amoeba found in humans
-Found in teeth and gums, in gingival pockets, and crypts of tonsils
-Only trophozoites, cannot become cysts
-Quick movement, with blunt pseudopodia
-Numerous food vacuoles
-In 95%of unhealthy mouths, 50% of healthy mouths
Describe Endolimax nana
-Is an Amoeba
-Is not a pathogen
-Indicates poor living conditions
-Encystmant can occur (BECOMES CYST)
-Short blunt pseudopodia
-Large food vacuoles
-Found in the large intestine
-Moves slowly (Dwarf Slug)
- Think nana as in Grandma
Describe Iodamoeba buetschlii
-Is an Amoeba
-Humans, primates, and mainly pigs are the host
-Slow movement
-Lives in the large intestine and feeds on GI FLORA
-Mature cysts are an infective form
-4-8 percent prevalence in humans
Describe Opportunistic Amoebas
- Can cause serious diseases or death in humans
-Usually free living
-Can invade the host’s tissues
Describe Vahkampfiidae (family)
-Has a flagellate and amoeboid stage
-Eruptive pseudopod formation
-Can produce cysts
-Can live in an aerobic soil, water, and air environment
-Can become facultative parasites in vertebrates
-Binary fusion occurs in the amoeboid form
Describe Naegleria fowleri
-Brain-Eating Amoeba
-Causes Primary Amebic Meningoencephalitis AKA (PAM)
-Has a flagella no pseudopodia in the flagella stage
-Amoeboid stages have pseudopodia
-Single nuclei
-Acute stage–rapidly fatal and mainly occurs in children or young adults
-Forced in through water rushing up nose
-No known successful treatment
Describe Acanthamoeba
-Facultative parasite of humans
-No flagella present
-Causes chronic infection in the central nervous system
-Moves rapidly
-Causes keratitis
-Risk factors include
- Contact lenses
-Most common Amoeba in freshwater and soil BUT STILL RARE
-Challenging to treat
Apicomplexa Life Cycle
- Merogony–Merozoites–Gametogony–Gametes (Male and Female)–Gametes fuse–Zygote–Sporogony–Sporozoite (Enters host cell)-Back to the start with Merogony
Apicomplexa anatomy
-Polar Rings-Usually one or two present
-Conoid-A cone structure up at the anterior section of the parasite it is within the polar rings
-Microtubules in the anterior section of the parasite
-Micronemes–elongated bodies
THESE ARE STRUCTURES USED IN LOCOMOTION
–All parasitic
-No cilia or flagella
Order Eucoccidioida
- Family Hepatozoidae
-300 Species
-Blood-feeding arthropods are the definitive host
-Transmission usually by consumption of these hosts rather than a bite (For example, dog eats a tick)
Hepatozoan Americanum
-Ticks are the definitive host
- Gamonts occur in leukocytes
-Gametes penetrate gut
-Clinical signs–elevated temp, weight loss, anemia, lethargy, decreased mobility
Family Eimeridae
-Contains sporocysts and sporocysts contain one or more sporozoites
-Merogony and gamotogony usually occur in the host
-Sprogony occurs outside the host
-Species-specific
-May be limited to a certain system or organ
-Vary in pathogenicity
Eimeria tenella
Intestinal ceca of chickens
Destroys tissues
High mortality in young birds
Infection occurs in contaminated feed and water Sporozoites exit oocyst in small intestine
Feed on host cells to become meronts(Which is an asexual reproduction)
Oocysts called sporonts and they are diploid
Can produce 2.52 million merozoites
Clinical signs–bloody diarrhea, death, closely packed large schizonts, cause hemorrhage, clogged blood
After infection no treatment
Toxiplasma Gondii
Cats are the definitive hosts,
found in every country
Found in warm-blooded animals
Asexual reproduction occurs in non-felid hosts
During acute infection, rapidly dividing stages occur (tachyzoites)
In chronic infections, they are in the brain, heart, and skeleton AKA Bradyzoites
Can hurt human fetus causing abnormalities
Freezing the cysts at -14C kills it
Sarcosystis
Tissue cysts form in muscle and brain tissue
Meishcers tubules
Oocysts sporulate in the linings of where mucus forms
Breaks down passage in intestine
Besnoitia
Cats are the definitive host
Intermediate Host–Lizards, opossums, rodents, donkeys, cattle
Thick walled cysts
Acute phase–weakness, fever, nodal swelling
Chronic phase–skin problems, infertility in bulls
Haemoproteus Sp.
Parasite of birgs and reptiles
Sexual phase occurs in flies
Exocythrocytic (Occurs outside red blood cells (Malaria)) occurs in lung capalaries
Can be found anywhere in the world
Found in pigeons
Haemoprotus columbe
Sporozoites injected at the bite site
Infected birds are usually are asymptomatic
Birds are restless and loose appetite
- lungs become congested and anemia may occur
Ciliates
Possess simple cilia or compound ciliary organelles during at least one life stage
Most have one or more micro and macronuclei
May or may not exhibit sexual reproduction
Most ciliates are free-living
May or may not exhibit sexual reproduction
Class Oligohymenophorea
Type of ciliate
Ichthypohtirius Mutifiliis
Cause ICH in fish
Attacks epidermis, cornea, and gill filaments
Asexual reproduction–1000 cells
Grey patches where the skin is colonized
Epistylis Spp.
Lives attached to a substrate, obligate ectocommensal
Sight specificity
Trichodina Spp.
Mobile
Prominent basal disc present
Aids in the attachment (teeth)
Hosts are Aquatic fish, amphibians, and invertebrates
May cause damage to the gills
Myxobolus cerebralis
Causes whirling disease in salmonids
-Fish swim in circles when disturbed or while feeding.
High mortality in young
Huge economic loss
HDamage to cranium and nervous system if fish survives
Phylum Microsporidia
Unicellular, obligate, spore-forming, intracellular organisms
- Highly resistant spores can exist for several years outside the host
-Found in protozoa, members of flatworms, roundworms, bugs, crustaceans, fish, reptiles
Microsporidian Life Cycle
Extrusion of polar filament from the spore
Sporoplasm-flows through tube gaming access
Once inside Sporoplasm multiplies and once the spores mature burst the cell wall
Microsporidians and Myxozoans Similarities
Can affect vertebrate and invertebrate hosts
Both require a 2nd host
Both have polar filaments
Mesozoans
Tiny ciliated organisms that parasitize invertebrates
Lack of digestive, circulatory, nervous, and excretory system
The body has two layers of cells
Two distinct mesozoan groups
-Dicyemida
-Orthonectida
Dicyemida, Class Rhombozoa
Marine invertebrates
parasites of renal organs
- occurring free in kidney sac, or surrounding area
Mesozoans: Orthonectida
Bilaterally symmetrical and has no organs or tissues
No internal body cavity, digestive tract, or nervous system
The body consists of two cell layers
Possess the smallest genome of multicellular animals
18 species parasitize invertebrates
Brittle stars is an example
Myxozoans
Spores are multicellular and structurally diverse
Infects host by piercing it
Invertebrates: Undergoes merogony and develops actinospores
Vertebrates: mostly fish and asexual reproduction
Platyhelminthes
Dorsoventrally Flattened
Usually Leaf-shaped or oval
No body cavity
Bilaterally symmetrical
Elaborate nervous system (Ladder)
Most are parasitic and thrive in many environments
Digestion is extracellular
Trematoda; Aspidobothria
Loose parasitic relationship with mollusks
It looks like a grenade
Tegument
The digestive system is simple
Osmoregulatory system
The nervous system is complex for a flatworm
Males have multiple testes and females have lobated ovaries
Can survive days in water or saline
The normal host is the mollusk
Can survive in fish or turtles if ingested
Aspidogaster conchicola
In the cavity of freshwater clams
Europe, Africa, and North America
Also seen in mollusks, turtles, and fish
Oval with long mobile neck
Eggs hatch in molluscan host
Young can develop without further migration
Stichocotyle nephrosis
In bile ducts of rays
Also found in crustaceans
Aspects of life cycle are unknown
Digenean Trematodes
flukes
Among the most common and abundant parasitic worms
Needs a 1st and 2nd or even 3rd host
Dorsobentrally flattened
Oval in shape
Very complex bodily systems
Digenean Life Cycle
Egg development
-Some may need to develop in the environment and some may hatch in the parents
Miracidium
-ciliated, possess penetration glands
-Active movement most find shot rapidly
Sporocyst–embryos develop into daughter sprocysts
Rediae
Cercariae–tails may be present
Metacercariae
Superfamily Echinostomoatoidea
Infect all classes of vertebrates
Circumoral collar of peg-like spines
Echinostomes
Slender worms
parasitize bile ducts of reptiles, birds, and mammals
Live anywhere and non-host specific
Echinostoma spp.
Eggs–miracidia–sporocysts–mother redia–cercariae–metacercarie
Human infected when raw snails are ingested
Fasciolidae
Large, leaf-shaped parasites of mammals
Needs a 2nd IH in water
Mostly on the liver of mammals
Fasciola jacksoni–anemia, weight loss, death in elephants
magna–exists in deer
Ribeiroia ondatrae
deformities in frogs
IH host –snails
2nd IH: fish, larval amphibians
DH: hawks, herons, badgers, muskrats
Paramphisotomoidea
Amphistomes
- thick fleshy worms
in dish, amphibians, reptiles, birds, and mammals
Paramphistomum cervi
In rumen(HOOFED ANIMALS) of domestic mammals
Most areas of the world
Cercariae are large
2nd IH metacercariae encyst on aquatic vegetation
Amphistome
Highly pathogenic
-often kills host
-no adequate prevention or treatment
Stichorchis subtriquetrus
Parasite of beavers
Metacercariae on sticks at bottom of ponds
Mother redia develops in miracidium–released in snail after penetration
Adult worms live in the stomach of beavers and can lead to mortality in some cases
Megalodiscus temperatus
Rectum and bladder of amphibians
Posterior sucker is huge
No second intermediate host
cercariae have eyespots and swim toward lighted areas
Plagiorchiformes and Opisthorchiformes
Wide variety of vertebrates
All cercariae encyst in a 2nd IH in contrast to many echinostomades
Order plafiorchiida
AHave a simply tail with dorsal finfold
Eggs must be eaten by a snail before hatching
Diceocodelidae
Liver flukes
Some parasitize bladder inestine or pancreas
Land snails are 1st IH
Pointed at both ends for body shape
Dicrocoelium dendriticum
Lives in bile ducts of the liver
1st IH is a land snail
Snail deposits slime balls covered in cercaria as it moves
An ant will ingest the slime balls
Known as the lancet fluke
Wait for grazing animals to eat them from plants mainly grazing animals
Troglotrematidae
Oval, thick flukes
Parasites of lung intessting
Nanophyetus salmincola
Causes salmon disease, dogs ingest raw salmon is called rickettsial disease more formal
Snail hosts
Eggs metacercariae most common in kidneys, fins, and muscles hatch in water
Heterophyidae
tiny tear drop shaped flukes
Heterophyes heterophyes
Adults in the small intestine, in fish
DH becomes infected upon eating undercooked fish
Monogeneans
Hermaphroditic flatworms
External parasites of fish
Usually exist on gills
Usually in wide populations not as problematic because the fish are too spread out
Host and Sight specific
Life span is from a few days to a few years
If the host dies the parasite usually will die shortly after
Monogeneans Anatomy
Bilaterally symmetrical
Partially asymmetrical
Body colorless or grey
Monogenean Life Cycle
Single Host (NO IH)
Egg–> Onocomiracidium (in most species)–> Adult
Dacylogyrids
Marine and freshwater fish
Most common monogeneans
Often found on gills
Gyrodactylids
Economically significant pests –trout, bluegills, and goldfish
Common on freshwater fish
Possesses an Egg Cell Formation Region
Appear unable to swim
- Direct transfer must take place
Infections spread easily in hatcheries
