Helminths of Small Animals I

Question 1

who do toxocara infect?

Answer 1

dogs
cats

Question 2

who do ascaris infect?

Answer 2

pigs
people

Question 3

where in the body do ascarididae reside?

Answer 3

small intestine

Question 4

what animal(s) do Ascaris suum infect?

Answer 4

pigs

Question 5

true/false: Ascaris suum have an indirect life cycle

Answer 5

false: direct

Question 6

summarize the life cycle of Ascaris suum

Answer 6

infective eggs ingested
hatch in small intestine
L3 migrate intravascularly to liver, heart, lungs
burrow into bronchioles and migrate up
swallowed and mature and mate in small intestine

Question 7

what animal(s) do Parascaris equorum infect?

Answer 7

horses

Question 8

what animal(s) do Toxocara canis infect?

Answer 8

dogs
zoonotic

Question 9

how does the life cycle/infection of Toxocara canis differ from that of Ascaris suum?

Answer 9

third stage larvae live in somatic tissues
transmammary and transplacental infection to pups
infection can occur by ingestion of paratenic hosts

Question 10

what can migrating larvae impact?

Answer 10

viscera
eye
nervous system

Question 11

what are the clinical signs of Toxocara canis?

Answer 11

not likely in older dogs
puppies: noisy breathing, cough, vomiting, diarrhea, stunted growth rate, distended abdomen
abdominal discomfort
death rarely due to obstruction/perforation
same in Toxocara cati

Question 12

what is a way to identify Toxocara canis using a microscope?

Answer 12

cervical alae (clear cuticular flanges anterior end)

Question 13

how can Toxocara canis and Toxocara cati be confirmed?

Answer 13

eggs in feces

Question 14

how does transmission of Toxocara cati differ from Toxocare canis?

Answer 14

no transplacental transmission in cats

Question 15

how can cats be infected with Toxocara cati?

Answer 15

ingest infective eggs
transmammary route
paratenic host

Question 16

how can Toxocara cati be identified using a microscope?

Answer 16

cervical alae are broad and end abruptly

Question 17

how can Toxocara canis be treated to keep newborn puppies from getting it?

Answer 17

dose bitch starting 3 weeks before and ending 3 weeks after birthing with fenbendazole

Question 18

what animal(s) does Toxoscaris leonina infect?

Answer 18

dogs and cats

Question 19

what other worm is Toxoscaris leonina similar to morphologically as an adult?

Answer 19

Toxocara canis: similar cervical alae

Question 20

summarize the life cycle of Toxoscaris leonina

Answer 20

ingest eggs or L2 larvae (dogs) or paratenic host (cats)
larvae to mature adult in small intestine: no migratory phase

Question 21

what are the clinical signs of Toxoscaris leonina?

Answer 21

not serious in light infections
heavier: diarrhea, dehydration, poor health, rarely death

Question 22

how can Toxoscaris leonina be identified in feces?

Answer 22

eggs: thick, smooth outer shell, with empty space inside of egg

Question 23

what animal(s) do Baylisascaris procyonis infect?

Answer 23

raccoons are host
zoonotic

Question 24

summarize the life cycle of Baylisascaris procyonis

Answer 24

ingest eggs
larvae hatch and enter wall of small intestine
develop to adult worms in small bowel

Question 25

what makes infection of Baylisascaris procyonis so pathogenic?

Answer 25

large and highly neurotropic fatal nervous system disease

Question 26

what are Baylisascaris procyonis' diagnostic features?

Answer 26

prominent lateral alae excretory columns

Question 27

how does Nanophyetus salmincola make organisms sick?

Answer 27

bacteria called Neorickettsia helminotheca: gram-negative in Anaplasmataceae family

Question 28

how is Nanophyetus salmincola transmitted?

Answer 28

eating undercooked/raw salmon, trout, pacific giant salamander

Question 29

how is salmon poisoning disease treated and what are the clinical signs?

Answer 29

tetracyclines and praziquantel, albendazole, fenbendazole high fever, weight loss, vomiting, diarrhea, lymphadenopathy, death 7-10 days

Question 30

what parasites can cause visceral larva migrans?

Answer 30

Toxocara canis Ascaris suum Toxocara cati

Question 31

what parasite causes fatal central nervous system disease?

Answer 31

Baylisascaris procyonis

Question 32

what is the treatment for Baylisascaris procyonis in incidental hosts?

Answer 32

none, but anthelminthics may slow

Question 33

what causes enlarged mesenteric lymph nodes, weight loss, vomiting, fever, and diarrhea?

Answer 33

Neorickettsia helminthoeca disseminates in blood and lymph to lymphoid tissues