Porcine Top Respiratory Diseases Flashcards
what clinical signs are seen with porcine reproductive & respiratory syndrome in breeding herds?
abortions, early farrowing, anorexia, up to 100% neonatal mortality
what clinical signs are seen with porcine reproductive & respiratory syndrome in growing pigs?
transient disease with up to 20% mortality - cough, fever, & secondary infections with strep suis, glaserella parasuis, & mycoplasma species
what is the etiology of porcine reproductive & respiratory syndrome?
RNA arterivirus (different strains) that invade pulmonary alveolar macrophages
what is seen on necropsy with PRRS?
lungs fail to collapse with mutlifocal consolidation & enlarged lymph nodes
what is seen on histopath of PRRS?
necrotizing interstitial pneumonia, lymphoid hyperplasia, & focal follicular necrosis
T/F: in PRRS pigs, if it is a low level of infection & not causing significant economic losses may do nothing but monitor
TRUE
what is the most costly disease in pig production?
PRRS
why is biosecurity so important in preventing PRRS?
highly contagious & infectious disease - must test new animals prior to entry
what is the treatment for PRRS?
none - supportive care to prevent secondary infections
what is the classic case presentation of acute influenza a in pigs?
transient disease that is worse in younger pigs & better in vaccinated pigs - sudden onset of fever & cough, 100% morbidity, & nasal discharge
what signs are seen in endemic IAV in sow farms/nurseries?
poor reproductive performance, piglets coughing in farrowing crates, & cough/poor performance in nursery
what gross lesions are seen in IAV?
sharply demarcated multifocal areas of consolidation
what microscopic lesions are seen in IAV?
degeneration/necrosis of the epithelium in the bronchi/bronchiolo, hyperemia & dilation of the capillaries, & infiltration of alveolar septae with lymphocytes
how is IAV diagnosed?
PCR on oral fluids, nasal swabs on febrile pigs for PCR, & PCR on lung tissue
what treatment is done for an outbreak of IAV?
supportive care (aspirin, NSAIDS), get fevers down so they will eat/drink, & treat bacterial infections with abx
how is IAV prevented?
vaccination of piglets & sows - homologous vaccine is best
why is IAV no longer called swine flu?
because it is zoonotic & can affect humans/other animals
T/F: IAV is one of the most common respiratory pathogens of pigs
TRUE
what is the classic case presentation of actinobacillus suis in pigs?
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)
what is the etiology of actinobacillus suis?
ubiquitous small gram negative rod
what gross lesions are seen with actinobacillus suis?
petechial/ecchymotic hemorrhages in multiple organs, serous/serosanguinous exudates in thx/abd cavities, pleuritis/pericarditis/arthritis/miliary abscesses in variety of organs
what microscopic lesions are seen in actinobacillus suis?
foci of necrosis in multiple organs associated with bacterial thromboemboli
how is actinobacillus suis spread?
spread with nose to nose contact
how is actinobacillus suis treated?
abx, abx for pigs that have been nose to nose with piglets that died, & follow abx with water if needed
what is the prognosis of actinobacillus suis infections in pigs?
good with treatment
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
TRUE
how is actinobacillus suis diagnosed?
culture visible lesions at necropsy
what are the 2 syndromes seen with porcine circovirus in pigs early in grower (older than 10 weeks)?
post weaning wasting multisystemic syndrome (diarrhea) & porcine dermatitis & nephropathy syndrome (pale to icteric skin with coalescing raised red to purple lesions covering the rump)
how are gilts in sow herds affected by porcine circovirus?
increased mummified fetuses & late term abortions
what is the etiology of porcine circovirus?
small non-enveloped DNA virus
what gross lesions are seen with porcine circovirus?
enlarged lymph nodes, lungs don’t collapse with interlobular edema, & kidneys are enlarged/pale & subcapsular surface surface may have white spotted foci
what microscopic lesions are seen with porcine circovirus?
lymphocytic histiocytic infiltration of lymphoid tissues & sloughing of lung epithelium with fibroplasia
how is porcine circovirus diagnoed?
gross/microscopic lesions, PCR on oral fluids, IHC/PCR on lung tissue/lymph nodes & histopathologic lesions of lymphocytic histiocytic infiltration of lymphoid tissue
what treatment is used for porcine circovirus?
no treatment
what is the prognosis of porcine circovirus?
poor in unvaccinated/undervaccinated pigs
T/F: porcine circovirus is ubiquitous in pigs world wide
TRUE
how is porcine circovirus prevented?
vaccination
mycoplasma hyopneumoniae causes what disease in pigs?
enzootic pneumonia
what is the classic case presentation of enzootic pneumonia in pigs?
deep barking/non-productive cough & pigs stop growing - may occur in sow farms if positive animals are introduced to a negative farm
what is the etiology of enzootic pneumonia of pigs?
slow growing bacterium - mycoplasma hyopneumoniae
what gross lesions are seen with enzootic pneumonia?
cranioventral consolidation of the lungs (apical, cardiac, & accessory)
what microscopic lesions are seen with enzootic pneumonia?
lymphocytes in perivascular, peribronchial, & peribronchiolar tissues, & cuffing/lymphoid hyperplasia around the airways
how is enzootic pneumonia diagnosed?
not a good candidate for culture - PCR on lung, oral fluids, & tonsil scraping & ELISA in negative herds
how is enzootic pneumonia treated?
nothing - prevent with vaccination
how is enzootic pneumonia prevented?
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
T/F: poor growth may persist after infection from enzootic pneumonia
TRUE
what age of pigs are often affected by atrophic rhinitis?
3-6 week old piglets
what clinical signs are seen with atrophic rhinitis?
sneezing, nasal discharge, tear staining, & decreased growth rate
what is the etiology of atrophic rhinitis?
bordetella bronchiseptica & pasteurella multocida
what gross lesions are seen with atrophic rhinitis?
mild to moderate turbinate atrophy & deviation of nasal septum
what microscopic lesions are seen with atrophic rhinitis?
disruption of normal bone formation in the turbinates
how is atrophic rhinitis prevented?
vaccination - sow twice at pre-farrowing, piglets twice, & abx to sow at parturition
T/F: atrophic rhinitis is no longer a major health concern in the USA but it is still found at slaughter surveillance
TRUE
T/F: usually mild disease & turbinate damage may be reversible in some cases of atrophic rhinitis
TRUE
