L14-15

Question 1

Cause of chicken infectious anemia

Answer 1

• circovirus
• a hardy ss DNA virus
• ubiquitous worldwide

Question 2

Which chickens are most affected by chicken infectious anemia

Answer 2

Broilers and layers

Question 3

Only natural hosts of chicken infectious anemia

Answer 3

Chickens

Question 4

Trans. Of chicken infectious anemia

Answer 4

Vertical transmission is most important

Also horizontally

Question 5

When is clinical disease seen with chicken infectious anemia**

Answer 5

Only during first 2-3 weeks of life, after which chicks become resistant. However, ALL ages are susceptible to infection

Question 6

CS of chicken infectious anemia

Answer 6

ANEMIA = only specific sign

Low PCV
Blood may be slow to clot, prone to bleeding
Birds pale, depressed

Question 7

Mortality of chicken infectious anemia

Answer 7

5-10%, can be up to 60%

Question 8

Exacerbating “factors” of chicken infectious anemia

Answer 8

Marek'd dz
Infectious bursal dz
Inclusion body hepatitis virus
Staph
Clostridium
Mycotoxins
Stress

Question 9

Sequelae of chicken infectious anemia

Answer 9

• aplastic anemia
• generalized lymphoid depletion
• SC and IM hemorrhages
• immunosuppression
• secondary infections –> high mortality

Question 10

Dx of chicken infectious anemia

Answer 10

• CS, gross lesions

- PCR, IF, IHC, ELISA

Question 11

Prevention of chicken infectious anemia

Answer 11

• live modified virus vaccine protects parental flocks and passively protects chicks
• most flocks naturally exposed
• vaccinate 6 wks prior to onset
• vaccinate ALL birds and avoid spreading it to younger birds or layers

Question 12

Infectious bursal (Gumboro) disease cause

Answer 12

Birnavirus

-a highly contagious, stable virus

Question 13

Trans. Of infectious bursal (gumboro) disease

Answer 13

Fecal/oral, highly contagious

NO egg transmission, no carrier state**

Question 14

What species/age affected by gumboro dz?

Answer 14

Only chickens, usually chicks 3-6 wks

Question 15

2 forms of Infectious bursal (Gumboro) disease

Answer 15

1) sub-clinical: immunosuppression w/o CS; most economically important
2) clinical: rapid increase in mortality, 3-4 wks

Question 16

CS of Infectious bursal (Gumboro) disease

Answer 16

• rapid onset
• ruffled feathers
• depression, anorexia
• watery white diarrhea
• severe prostration
• death

Question 17

Gross lesions of Infectious bursal (Gumboro) disease

Answer 17

• swollen, exudative, hemorrhagic bursa of F**
• Hemorrhages in muscles +/- kidneys, proventriculus, gizzard
• renal tubules distended w/ urates

Question 18

Cardinal microscopic lesions of Infectious bursal (Gumboro) disease

Answer 18

• mostly in the bursa of F
• necrosis of lymphocytes in follicles
• edema, hyperemia, heterophils
• cystic cavities
• interfollicular fibroplasia
• follicular atrophy

Question 19

Dx of Infectious bursal (Gumboro) disease

Answer 19

• virus isolation in egg
• impression smears from bursa
• IF, PCR
• Agar gel precipitation (AGP)
• must determine pathotype of field virus involved in outbreak

Virulent strains –> INTRAfollicular staining
Non-virulent strains –> INTERfollicular staining

Question 20

Importance of ELISA with Infectious bursal (Gumboro) disease**

Answer 20

Used for monitoring vaccination response and maternal Ab persistence in young chicks

Question 21

Why vaccinate YOUNG CHICKS against gumboro disease?

Answer 21

Prevents immunosuppression, Mb, Mt after natural infection

Question 22

Why vaccinate BREEDERS against gumboro disease?

Answer 22

To stimulate development of high and persistent levels of Ab to be transferred to progeny during laying period

Question 23

Ab for Gomboro dz persist longer in layers or broilers?

Answer 23

Layers (7 vs. 4 days)