Porcine Top Respiratory Diseases

Question 1

what clinical signs are seen with porcine reproductive & respiratory syndrome in breeding herds?

Answer 1

abortions, early farrowing, anorexia, up to 100% neonatal mortality

Question 2

what clinical signs are seen with porcine reproductive & respiratory syndrome in growing pigs?

Answer 2

transient disease with up to 20% mortality - cough, fever, & secondary infections with strep suis, glaserella parasuis, & mycoplasma species

Question 3

what is the etiology of porcine reproductive & respiratory syndrome?

Answer 3

RNA arterivirus (different strains) that invade pulmonary alveolar macrophages

Question 4

what is seen on necropsy with PRRS?

Answer 4

lungs fail to collapse with mutlifocal consolidation & enlarged lymph nodes

Question 5

what is seen on histopath of PRRS?

Answer 5

necrotizing interstitial pneumonia, lymphoid hyperplasia, & focal follicular necrosis

Question 6

T/F: in PRRS pigs, if it is a low level of infection & not causing significant economic losses may do nothing but monitor

Answer 6

TRUE

Question 7

what is the most costly disease in pig production?

Answer 7

PRRS

Question 8

why is biosecurity so important in preventing PRRS?

Answer 8

highly contagious & infectious disease - must test new animals prior to entry

Question 9

what is the treatment for PRRS?

Answer 9

none - supportive care to prevent secondary infections

Question 10

what is the classic case presentation of acute influenza a in pigs?

Answer 10

transient disease that is worse in younger pigs & better in vaccinated pigs - sudden onset of fever & cough, 100% morbidity, & nasal discharge

Question 11

what signs are seen in endemic IAV in sow farms/nurseries?

Answer 11

poor reproductive performance, piglets coughing in farrowing crates, & cough/poor performance in nursery

Question 12

what gross lesions are seen in IAV?

Answer 12

sharply demarcated multifocal areas of consolidation

Question 13

what microscopic lesions are seen in IAV?

Answer 13

degeneration/necrosis of the epithelium in the bronchi/bronchiolo, hyperemia & dilation of the capillaries, & infiltration of alveolar septae with lymphocytes

Question 14

how is IAV diagnosed?

Answer 14

PCR on oral fluids, nasal swabs on febrile pigs for PCR, & PCR on lung tissue

Question 15

what treatment is done for an outbreak of IAV?

Answer 15

supportive care (aspirin, NSAIDS), get fevers down so they will eat/drink, & treat bacterial infections with abx

Question 16

how is IAV prevented?

Answer 16

vaccination of piglets & sows - homologous vaccine is best

Question 17

why is IAV no longer called swine flu?

Answer 17

because it is zoonotic & can affect humans/other animals

Question 18

T/F: IAV is one of the most common respiratory pathogens of pigs

Answer 18

TRUE

Question 19

what is the classic case presentation of actinobacillus suis in pigs?

Answer 19

acute death (affects all ages from sows/neonates to finishing pigs) may be accompanied by cough, lethargy, epistaxis, & sometimes discoloration of the ears - respiratory distress in finishing pigs (dyspnea & acute death)

Question 20

what is the etiology of actinobacillus suis?

Answer 20

ubiquitous small gram negative rod

Question 21

what gross lesions are seen with actinobacillus suis?

Answer 21

petechial/ecchymotic hemorrhages in multiple organs, serous/serosanguinous exudates in thx/abd cavities, pleuritis/pericarditis/arthritis/miliary abscesses in variety of organs

Question 22

what microscopic lesions are seen in actinobacillus suis?

Answer 22

foci of necrosis in multiple organs associated with bacterial thromboemboli

Question 23

how is actinobacillus suis spread?

Answer 23

spread with nose to nose contact

Question 24

how is actinobacillus suis treated?

Answer 24

abx, abx for pigs that have been nose to nose with piglets that died, & follow abx with water if needed

Question 25

what is the prognosis of actinobacillus suis infections in pigs?

Answer 25

good with treatment

Question 26

T/F: actinobacillus suis can be the primary pathogen causing disease but it can also be associated with viral diseases & it is sporadic making it difficult to prevent

Answer 26

TRUE

Question 27

how is actinobacillus suis diagnosed?

Answer 27

culture visible lesions at necropsy

Question 28

what are the 2 syndromes seen with porcine circovirus in pigs early in grower (older than 10 weeks)?

Answer 28

post weaning wasting multisystemic syndrome (diarrhea) & porcine dermatitis & nephropathy syndrome (pale to icteric skin with coalescing raised red to purple lesions covering the rump)

Question 29

how are gilts in sow herds affected by porcine circovirus?

Answer 29

increased mummified fetuses & late term abortions

Question 30

what is the etiology of porcine circovirus?

Answer 30

small non-enveloped DNA virus

Question 31

what gross lesions are seen with porcine circovirus?

Answer 31

enlarged lymph nodes, lungs don't collapse with interlobular edema, & kidneys are enlarged/pale & subcapsular surface surface may have white spotted foci

Question 32

what microscopic lesions are seen with porcine circovirus?

Answer 32

lymphocytic histiocytic infiltration of lymphoid tissues & sloughing of lung epithelium with fibroplasia

Question 33

how is porcine circovirus diagnoed?

Answer 33

gross/microscopic lesions, PCR on oral fluids, IHC/PCR on lung tissue/lymph nodes & histopathologic lesions of lymphocytic histiocytic infiltration of lymphoid tissue

Question 34

what treatment is used for porcine circovirus?

Answer 34

no treatment

Question 35

what is the prognosis of porcine circovirus?

Answer 35

poor in unvaccinated/undervaccinated pigs

Question 36

T/F: porcine circovirus is ubiquitous in pigs world wide

Answer 36

TRUE

Question 37

how is porcine circovirus prevented?

Answer 37

vaccination

Question 38

mycoplasma hyopneumoniae causes what disease in pigs?

Answer 38

enzootic pneumonia

Question 39

what is the classic case presentation of enzootic pneumonia in pigs?

Answer 39

deep barking/non-productive cough & pigs stop growing - may occur in sow farms if positive animals are introduced to a negative farm

Question 40

what is the etiology of enzootic pneumonia of pigs?

Answer 40

slow growing bacterium - mycoplasma hyopneumoniae

Question 41

what gross lesions are seen with enzootic pneumonia?

Answer 41

cranioventral consolidation of the lungs (apical, cardiac, & accessory)

Question 42

what microscopic lesions are seen with enzootic pneumonia?

Answer 42

lymphocytes in perivascular, peribronchial, & peribronchiolar tissues, & cuffing/lymphoid hyperplasia around the airways

Question 43

how is enzootic pneumonia diagnosed?

Answer 43

not a good candidate for culture - PCR on lung, oral fluids, & tonsil scraping & ELISA in negative herds

Question 44

how is enzootic pneumonia treated?

Answer 44

nothing - prevent with vaccination

Question 45

how is enzootic pneumonia prevented?

Answer 45

vaccinate piglets twice & in replacement gilts depending on the status of sow herd they are entering - antimicrobials guring outbreaks in late finishing pigs - hard to eliminate cough in pigs

Question 46

T/F: poor growth may persist after infection from enzootic pneumonia

Answer 46

TRUE

Question 47

what age of pigs are often affected by atrophic rhinitis?

Answer 47

3-6 week old piglets

Question 48

what clinical signs are seen with atrophic rhinitis?

Answer 48

sneezing, nasal discharge, tear staining, & decreased growth rate

Question 49

what is the etiology of atrophic rhinitis?

Answer 49

bordetella bronchiseptica & pasteurella multocida

Question 50

what gross lesions are seen with atrophic rhinitis?

Answer 50

mild to moderate turbinate atrophy & deviation of nasal septum

Question 51

what microscopic lesions are seen with atrophic rhinitis?

Answer 51

disruption of normal bone formation in the turbinates

Question 52

how is atrophic rhinitis prevented?

Answer 52

vaccination - sow twice at pre-farrowing, piglets twice, & abx to sow at parturition

Question 53

T/F: atrophic rhinitis is no longer a major health concern in the USA but it is still found at slaughter surveillance

Answer 53

TRUE

Question 54

T/F: usually mild disease & turbinate damage may be reversible in some cases of atrophic rhinitis

Answer 54

TRUE