parasitology 1

Question 1

what is a parasite

Answer 1

organism that lives in or on another living organism (host) obtaining from it all or part of its nutrients
cause harm to the host
some degree of adaptive structural modification
only include those organisms that are eukaryotes except fungi

Question 2

direct life cycle

Answer 2

simple
one host

Question 3

indirect life cycle

Answer 3

complex
2 or more host

Question 4

definitive host

Answer 4

host in which sexual reproduction takes place
final host

Question 5

intermediate host

Answer 5

host in which only immature stage grow and develop
may or may not occur asexual reproduction

Question 6

paratenic host

Answer 6

host not required to complete the life cycle but help parasite get to the host
no parasitic development of any kind takes place
transport host

Question 7

normal host

Answer 7

animals recognized as part of the normal life cycle

Question 8

abnormal, aberrant host or dead end

Answer 8

animal not normally used as a host
often (not always) associated with disease
animals could be abnormal definitive, intermediate or transport host depending on which stage of the parasite life cycle is present

Question 9

reservoir host

Answer 9

host serves as as ource of infection for other animals

Question 10

vector

Answer 10

invertebrate, usually arthropod that transmits infectious disease

Question 11

biological vector

Answer 11

parasite develope in the vecctor

Question 12

mechanical vector

Answer 12

like a contaminated instrument

Question 13

endoparasite

Answer 13

internal parasite
infection

Question 14

ectoparasite

Answer 14

external parasite
infestation

Question 15

microparasites

Answer 15

multiple inside host

Question 16

macroparasites

Answer 16

mate, produce eggs and leave in the environment
does not multiple inside the host

Question 17

infectious

Answer 17

caused or capable of being communicated by infection

Question 18

infective

Answer 18

parasite stage capable of infect the host
many parasites are not able to cause infection until after some period of development in the environment

Question 19

prepatent period

Answer 19

internal parasites-mainly macroparasites
time required following infection of the definitive host to reach repdocutive maturity (secual reporuction) period before production of eggs/cysts
not the same as the generation time :egg to egg

Question 20

patency

Answer 20

adult reproductive infection

Question 21

will an exposed animals become infected

Answer 21

parasite usually require appropriate stimulus to recognize potential host
intracellular parasite need specific receptors on cells of appropriate hosts
GI helminths often need specific cues like pH and bile

Question 22

pathogenesis depends on three factors

Answer 22

status of host defenses
number of parasites present
pathogenicity of those parasites

Question 23

pathology from parasitic infections

Answer 23

parasite-induced trauma to the cells, tissue and organs
changes in cellular growth patterns
interference with host nutrient acquisition
toxins released by parasites
the host immune response to infection

Question 24

70-30 rule

Answer 24

top 30% has 71% of the worms
bottom 70% has 29% of worms

Question 25

veterinarian roles

Answer 25

significance of infection
prevention of infection
integrated parasite management

Question 26

diagnosis of parasites

Answer 26

morphologic-blood, tissue, feces, gross inspection
immunologic assay-antigen or antibody test-protozoan parasites
molecular test-increased (PCR)

Question 27

parasitological principles

Answer 27

parasitic infection is not synonymous with parasitic disease
immunity often prevents disease but infection/infestation
young animals are more susceptible (poor baby rule)
parasites that have stages that must develop and survive in the environment are at the mercy of weather
if you want to kill a parasite in the environment desiccate it