Nematodes - Exam 3

Question 1

nematodes common name

Answer 1

roundworms

Question 2

nematodes characteristics

Answer 2

free living or parasitic (soil, plant, animal), alimentary canal, sexes usually separate, direct/indirect life cycles, look like spaghetti, bursa (how male holds onto female)

Question 3

2 examples of nematodes

Answer 3

hookworm & mammomonogamus (copulate forever, Y shaped)

Question 4

nematode characteristics for ID

Answer 4

bursate (male), vulva, mouth (shape, teeth), esophagus, size

Question 5

life cycle

Answer 5

Egg, L1, L2, L3, L4, L5, Adult

Question 6

infective larva stage for direct life cycle

Answer 6

L3

Question 7

infective larva stage for direct life cycle in an egg

Answer 7

L2

Question 8

infective larva stage for direct life cycle

Answer 8

L1 to IH

Question 9

infective larva stage for indirect life cycle

Answer 9

L3 to FH

Question 10

5 ways to survive

Answer 10

periparturient rise, survival of eggs with larva, paratenic host, transmammary, transplacental

Question 11

periparturient rise

Answer 11

increase in number of adult eggs & worms when host immune system decreases i.e.: pregnancy

Question 12

2 ways to avoid immune system

Answer 12

arrested development, hypobiosis: arrest until favorable conditions (fixed shell helps)

Question 13

ancylostoma caninum

Answer 13

“hookworm”, zoonotic, direct life cycle: adult worm lay egg in S1, eggs in feces, eggs hatch & develop into infected larvae, either: penetrate skin, ingested, passed to puppies, 5 modes of infection: percutaneous penetration oral mucosa, po, paratenic hosts (rat), transplacental (rare), transmammary, arrested development and lung migration (coughing)

Question 14

ancylostoma caninum adults

Answer 14

1-2cm, small, hook, SI, cause hemorrhaging/anemia, attach to intestinal villi with large mouth (buccal) cavity

Question 15

ancylostoma caninum eggs

Answer 15

thin, oval, shelled, 60-40 um

Question 16

“leakage”

Answer 16

need to treat every 2 weeks because of the arrested worms

Question 17

clinical signs

Answer 17

acute/hemorrhagic anemia, moist eczema, ANEMIA, weakness, respiratory disease (pneumonia), -iasis, diarrhea/blood & mucous, weight loss, poor hair coat

Question 18

T/F: helminth eggs will develop to 1st stage larvae in their host ; why

Answer 18

false ; develop outside body so level infection related to environmental exposure

Question 19

how is a nematode usually diagnosed in a living host?

Answer 19

egg in feces