Lecture 9 10/17/24

Question 1

What age of pig is found in a farrowing barn?

Answer 1

piglets from birth to weaning at about 21 days

Question 2

What age of pig is found in a nursery barn?

Answer 2

feeder pigs 3 to 9 weeks of age

Question 3

What age of pig is found in a finishing barn?

Answer 3

finishing/market hogs 9 to 20 weeks of age

Question 4

How are sows organized within their barn?

Answer 4

based on farrowing date

Question 5

Why is it important to maintain a temperature of around 95 degrees in the farrowing barn?

Answer 5

to prevent cold stress that would predispose the piglets to illness/infection

Question 6

Why is it important to regularly clean the finishing barn?

Answer 6

ammonia smell can come up through the slatted floor and cause poor air quality

Question 7

What stressors can impact a pig at weaning?

Answer 7

-nutritional stress
-cold stress
-respiratory stress
-social stress

Question 8

What are the antemortem diagnostics that are commonly done in pigs?

Answer 8

-physical exam
-nasal/nasopharyngeal culture
-tonsillar scraping
-sacrfice and necropsy

Question 9

What are the therapeutic options used in pigs?

Answer 9

-parenteral or in-feed antibiotics
-NSAIDs
-depopulation/repopulation

Question 10

What are the characteristics of atrophic rhinitis?

Answer 10

-two bacteria work together to cause synergistic disease
-involves Bordetella bronchiseptica and Pasteurella multocida
-type D toxin produced by P. multocida

Question 11

What is the pathophysiology of atrophic rhinitis?

Answer 11

-piglets acquire B. bronchiseptica from sow
-B. bronchiseptica causes mucosal damage
-P. multocida co-colonizes nasal cavity
-toxin produced by P. multocida induces osteoclastic activity

Question 12

How does age of the pig impact the severity of atrophic rhinitis?

Answer 12

pigs that get infected at a younger age will have more severe turbinate atrophy

Question 13

What are the consequences of atrophic rhinitis?

Answer 13

-leads to secondary bact. infection
-poorer performance compared to uninfected pigs

Question 14

What are the clinical signs of atrophic rhinitis in farrowing/nursery pigs?

Answer 14

-sneezing
-nasal discharge

Question 15

What are the clinical signs of atrophic rhinitis in finishing pigs?

Answer 15

-distortion of snout and face
-excess lacrimation
-epistaxis
-failure to thrive

Question 16

What percent of market hogs have some sort of atrophic rhinitis lesion?

Answer 16

50-70%

Question 17

What are the characteristics of atrophic rhinitis treatment?

Answer 17

-mass medication by adding antibiotics to feed
-animal must be well enough to eat
-sickest animals likely to remain infected

Question 18

How is atrophic rhinitis prevented?

Answer 18

-vaccine given to sows
-improved management
-ventilation
-continuous slaughter checks

Question 19

Which bacteria causes necrotic rhinitis?

Answer 19

Fusobacterium necrophorum

Question 20

What is the pathophysiology of necrotic rhinitis?

Answer 20

F. necrophorum colonizes damaged mucosa that results from trauma (such as trimming milk teeth)

Question 21

What are the clinical signs of necrotic rhinitis in neonates/weaners?

Answer 21

-severe swelling of the nose
-abscessation
-foul breath
-facial deformities
-bull nose

Question 22

What are the treatment options for necrotic rhinitis?

Answer 22

-euthanasia
-wound debridement

Question 23

What are the characteristics of inclusion body rhinitis?

Answer 23

-caused by porcine cytomegalovirus
-gamma herpesvirus
-latency in leukocytes

Question 24

What is the pathophysiology of inclusion body rhinitis?

Answer 24

-latently infected sow acts as reservoir
-stressful event causes sow to shed virus and expose piglets
-virus replicates in nasal and ocular tissue

Question 25

What are characteristics of the influenza virus?

Answer 25

-orthomyxovirus -RNA virus -segmented genome

Question 26

What are the two influenza envelope proteins and their purpose?

Answer 26

-hemagglutinin: used to enter cells -neuraminidase: used to leave cells

Question 27

Which influenza strains are the main strains found in pigs?

Answer 27

-H1N1 -H3N2 -H1N2

Question 28

What is antigenic drift?

Answer 28

mutations in the genetic structure of the virus

Question 29

What is antigenic shift?

Answer 29

reassortment of the genome segments of the virus

Question 30

Why is it important that pigs can be infected with both avian and human influenza strains?

Answer 30

pigs serve as a hub for viral reassortment

Question 31

What are the characteristics of influenza transmission?

Answer 31

-virus likely circulates at low levels in the herd and waits for increased susceptibility -transmission occurs through resp. secretions -replication occurs in nasal, tracheal, and bronchial epithelium

Question 32

What are the characteristics of influenza infection?

Answer 32

-mild to severe necrosis of the resp. epithelium leads to lung cell death and consolidation -viral shedding can occur within 48 hours of infection -clinical signs begin around 4 days after infection -post-infection virus can be shed for up to 3 days

Question 33

What are the clinical signs of influenza in pigs?

Answer 33

-diarrhea -coughing -sore throat -lethargy -lack of appetite -sneezing -nasal and ocular mucous -fever -weight loss -poor growth

Question 34

How is influenza virus diagnosed?

Answer 34

-PCR -viral isolation -serology -indirect fluorescent antibody

Question 35

What are the characteristics of influenza prevention?

Answer 35

-vxs are not reformulated fast enough to provide good immunity -vxs can reduce disease severity -better to follow all in/all out -reduce stress and temp. changes -depopulate in the face of severe epidemics