Lecture 17 4/11/24

Question 1

What are the characteristics of Hemosporidia?

Answer 1

-live in the hematopoietic system of vertebrates
-indirect life cycles
-transmitted by bloodsucking arthropods (ticks)
-unlimited number of asexual generations

Question 2

What are the characteristics of Babesia spp.?

Answer 2

-intraerythrocytic parasite
-transmitted by ticks or mixing of blood

Question 3

Which dog breed often gets Babesia canis?

Answer 3

greyhounds

Question 4

Which arthropod transmits Babesia canis?

Answer 4

Rhipicephalus sanguineus

Question 5

Which dog breeds often get Babesia gibsoni?

Answer 5

-pit bull terriers
-staffordshire terriers

Question 6

What are the characteristics of Babesia canis?

Answer 6

-vertebrate host is dogs
-PPP of 1-3 weeks
-spread by Rhipicephalus sanguineus
-5 um

Question 7

What are the characteristics of Babesia gibsoni?

Answer 7

-vertebrate host is dogs
-PPP of 1-3 weeks
-spread by Rhipicephalus sanguineus
-1.5 to 3 um

Question 8

How does Babesia cause disease?

Answer 8

-rupture of RBCs leads to intravascular hemolysis and hemolytic anemia
-immune-mediated clearance of parasitized RBCs adds to anemia
-parasitized cells are sequestered in spleen; extravascular and intravascular hemolysis both occur

Question 9

What are the clinical signs of Babesia?

Answer 9

-hemolytic anemia
-fever
-anorexia/weight loss
-weakness/depression
-icterus
-hemoglobinuria
-inc. pulse and respiration
-splenic and hepatic enlargement
-death

Question 10

How is Babesia diagnosed?

Answer 10

-microscopy
-IFA
-PCR and sequencing
-response to treatment

Question 11

How is Babesia controlled/prevented?

Answer 11

-tick control
-screening blood donors
-discouraging dog fighting and dog-to-dog transmission

Question 12

Which Babesia spp. is seen in cattle?

Answer 12

B. bigemina

Question 13

Which Babesia spp. is seen in humans and rodents?

Answer 13

B. microti

Question 14

Which Babesia spp. are seen in horses?

Answer 14

B. equi
-B. caballi

Question 15

What are the characteristics of Cytauxzoon felis?

Answer 15

-rapidly fatal disease of domestic cats (DH)
-seen in indoor and outdoor cats anywhere where ticks are present (vector)
-merozoites are 1-2 um and in RBCs
-schizonts are in macrophages

Question 16

Why can the Cytauxzoon felis schizonts being in macrophages lead to infarcts?

Answer 16

they get too large and form clumps, blocking blood flow

Question 17

What are the clinical signs of Cytauxzoon felis?

Answer 17

-anorexia and depression
-fever
-anemia
-icterus
-dehydration
-marked dyspnea
-disseminated intravascular coagulation
-shock
-close to 100% fatality

Question 18

What signs of Cytauxzoon felis are seen at necropsy?

Answer 18

-dark, enlarged spleen
-enlarged, reddened lymph nodes
-lungs that are diffusely reddened, consolidated, and petechiated

Question 19

How is Cytauxzoon felis diagnosed?

Answer 19

-microscopic diagnosis of piroplasms in erythrocytes
-ID of large schizonts in splenic, lymph node, or bone marrow aspirates/impression smears
-molecular diagnosis/PCR

Question 20

How is Cytauxzoon felis prevented?

Answer 20

-tick control/tick prevention products
-keep cats indoors

Question 21

What are the characteristics of Hepatozoon americanum and canium?

Answer 21

-vert. host is dogs/coyotes, raccoons, cats
-inv. host/vector is ticks
-paratenic hosts are mammals with tissue cysts

Question 22

What are the clinical signs of Hepatozoonosis?

Answer 22

-musculoskeletal disease
-disseminated myositis
-muscle pain
-ocular discharge
-fever
-lethargy
-leukocytosis
-periosteal proliferation
-stiff gait and stance