3 + 4 - Arthropod and Protozoa Intro Flashcards
What are important groups of arachnidas and insectas?
Arachnica’s - Mites and Ticks (Acari)
Insecta - Bugs (hemiptera), life (mallophaga and anoplura), fleas (siphonoptera) and flies (diptera)
What are mites?
Dorso-ventrally flattened, six legs as larva, eight legs as nymph and adult, variable host specificity, microscopic and “hairy”
Burrowing mites have short legs
Surface mites have long legs
In sarcoptes, how long until the life cycle is complete?
10-14 days
What are ticks?
dorso-ventrally flattened, sick legs as larva, eight legs as nymph and adult, not very host specific, macroscopic, smooth
Hard ticks - ixodidae
Soft Ticks - Argasidae
What are the life stages of ticks and their legs?
Egg -> larva (3 pairs of legs) -> nymph (4 pairs of legs -> adult
What is a one host tick?
attached to a host as a larva, feeds and moults to a nymph and adult and falls off original animal as adults which will then lay eggs in the environment weeks to months later
What are two host ticks?
attaches to host 1 as larva, feeds and moults to nymph and falls off. Moults to an adult in enviro and finds new host as an adult, then mates on host and falls off into the environment
What is a 3 host tick?
attaches to host 1 as larva, feeds and fall off to moult to a nypmh and attach to host 2, feeds and falls off into enviro. Moults into an adult and attaches to host 3 and mates on the host then falls off to lay eggs
What are common characteristics of insects?
three pairs of legs
3 distinct body regions (head, thorax, abdomen)
Head - two eyes, 2 antennae and complex mouthparts
Thorax - six legs and anywhere from 0-4 wings
Abdomen
Repro prods eggs or larvae
Describe some common characteristics of bugs? give an example of them
dorso-ventrally flattened, six legs, variable host specifity
Bed bugs, assassin bugs
What are cimicidae?
bed bugs
What are reduviidae?
Assasin bugs, kissing bugs, cone noses
What is the life cycle of bed bugs?
cimex lectularius
Adults -on host only to feed
Eggs - in environment
Nymphs - on host only to feed
What are common characteristics of lice? Give an example of them
Dorsoventrally flattened, six legs, quite host specifity
Ex. Mallophaga - chewing/biting lice
Anoplura - Sucking lice
What are mallophaga?
chewing/biting lice
Head wider than thorax
What are anoplura’s?
sucking lice (head narrower than thorax)
What is the life cycle of lice? how long does it need to complete in cattle?
Adults on host feeding
Eggs or nits, on host
Nymphs on host feeding
Can take 3-4 weeks for cattle lice to mature
What are characteristics of fleas
laterally flattened, six legs, not host specific. How long until its complete?
What is the life cycle of fleas?
adults on host, blood feed
Eggs in enviro
larvae in enviro
Pupae in enviro
<3 wks to complete
What are some examples of nematoceras?
mosquitos, blackflies, midges
What are some examples of brachyceras
horseflies, deer flies
What are some examples of cyclorhaphas?
faceflies, horn flies, botflies
How might arthropods harm their human hosts?
Annoyance - dec feeding, sleep and poor haircouat
bloodloss - lice can drop a pcv to <10%
Prod venoms/toxins - tick paralysis(ascending flaccid paralysis, spider bites
Dermatosis - manage mites
Myasis (infection of the flesh of living anims w/ fly larvae - cattle warbles
allergic reactions - flea dermatitis, dust mites, anaphylaxis from death of warbles in cattle
Vector for dz agents
mechanical vectors (transport hosts) - flies carry trypanosomes
Biological vectors (intermediate hosts - mosquitos carry heartworl, fleas carry dipylidium canium)
How do we diagnose arthropods
fiding adults of immature stages and identifying them (as best one can)
sometimes symptoms, sometimes test treatments
what is a protozoa
A single-celled, eukaryotic organism
approx 64k species described of which only about 7k are parasitic to animals. The rest are free-living
How are protozoans detected?
thru blood samples - hemoprotozoa, found in the erythrocytes within a stained blood smear, ticks and blood sucking insects often serve as thee IH and transmit RBC’s containing the hemoprotozoa. Can also find Ag’s or Ab’s in blood samples
Fecal samples - intestinal protozoa
Tissue samples
What 3 locomotor organelles do protozoa have that we can identify the type of protozoa
Flagella, cilia, and pseudopods “false feet”
What is a protozoan’s flagella?
A long, whiplike structure
single or multiple
flagellates Trichomonads, Leishmania, Giardia
Sometimes the flagellum passes backwards along the cell, jained at a few or several points and is thus termed an undulating membrane (genus trypanosoma)
What is a protozoans cilia?
short flagella, usually arranged in rows or tufts
typically found in various arrangements around the mouth and/or oral groove of the ciliates such as balantidium coli and ichthyophthirius multifilis
What is a protozoan’s pseudopods?
false feed
temporary extensions and retractions of the body wall to surround potential food particles or for movement
typical of amoebas such as entamoeba histolytica
What is a zoite in terms of protozoa?
body = zoite
sporozoite, bradyzoite, tachyzoite
What is trophozoite?
the stage of the protozoan life cycle that is capable of feeding, movement and repro; often too fragile to survive transfer to a new host
At what protozoan stage does transmission to a new host occur?
Cyst stage or oocyst stage
most metabolic funct are suspended when the parasite is encysted
cyst wall prevents desiccation and protects it from other enviro damage
What are important flagellates of vet med?
mucosoflagellates - direct life cycles - Ex giardia
Haemoflagellates - arthropod-transmitted - Ex trypansoma
What are important ciliates of vet med
direct life cyles ex balantidium coli
What are important sporozoa/apicomplexans in vet med?
coccidia - direct life cycles (GIT) - EX Eimeria
- indirect life cycles (tissue cysts) ex toxoplasma
Haemosporidia - Arthropod transmitted (babesia)
What are important amoebae in vet med
direct life cycles ex naegleria fowlerii
What are protozoan ciliates?
direct life cycle, asexual repro by binary fission
Ex. balantidium coli in swine and ichthyophthirius multifiliis in fish
Which of these three mucosoflagellates have a direct life cycle and an indirect life cycle?
Giardia spp. (D)
Tritrichomonas spp. (D)
Histomonas (I)
What problems or symptoms are because of protozoal infections?
diarrhea, fevers and flu-like symptoms, neurological signs, abortions, skin lesions
How do we diagnose protozoa?
apearance on fecal smear/flotation
immunoflurorescent tests
immunohistochemistry
serology
Molecular detection and identification
Fecal smears are simple, quick and low sensitivity but false neg’s common
What are fecal smears good to detech for protozoans?
trophozoits and cysts
What are fecal floats good for to diagnose for protozoans?
Oocysts (coccidia, sarcocytes)
