L27: Pt.3 Flashcards
Vena caval thrombosis
- most common in feedlot cattle
- CS: wt. loss, resp. Signs with anemia, wheezes, hemoptysis**
- rapid deterioration after hemoptysis
- Tx: penicillin, NaCl
- almost always fatal
- 2ary to rumen acidosis
Pathogenesis of vena caval thrombosis***
rumen acidosis, rotting grain in the rumen –> rumenitis –> Fusobacterium and Trueperella infections in the wall of the rumen –> transported via portal system to the liver –> liver abscesses –> abscesses impact the caudal vena cava –> caudal vena cava thrombosis –> pieces of septic thrombi break off, pass through the thrombus, and into the right heart –> septic pulmonary emboli –> pulmonary abscesses and aneurysms –> rupture into airways and bleed out via mouth and nose
Types of interstitial pneumonia
- Atypical interstitial pneumonia (aka ARDS)
- Hypersensitivity diseases
- chronic interstitial pneumonia
- parasitic pneumonias
Causes of Atypical interstitial pneumonia
- pasture-assoc.
- feedlot AIP
- moldy sweet potato toxicity
- Perilla ketone toxicity
- poison gases and fumes
Most common cause of respiratory dz after 30 days on a feedlot***
Atypical interstitial pneumonia (AIP)
-unknown cause
Pathologic findings of AIP
- lungs fail to collapse
- firm rubbery with interlobular or bullous emphysema
- affected lobules interspersed with normal
Histopath:
-Alveolar hyaline membrane formation and fibrin deposition
-edema
Type 2 pneumocyte proliferation
-hemorrhage, emphysema, interstitial inflammatory infiltrate
Acute Bovine Pulmonary Edema and Emphysema - ABPEE (“Fog Fever”)
-AIP in adult cattle >2 yrs
-occurs when transition to lush green pasture
-acute onset resp. Signs
-coughing rare
+/- emphysema
Metastatic pneumonia
- comes from septic emboli from jugular vein phlebitis, mastitis, metritis, footrot
- common agents: Fusobacterium, Trueperella, E. Coli, Staph, Strep
Tx/Prevent of ABPEE
Tx: avoid stress; flunixin, steroids, diuretics
Prevent: slowly introduce to pasture, graze young stock before adults, strip-grazing, ionophore abx (monensin or Iasalocid) BEFORE they go on pasture
Moldy Sweet Potato Toxicity
- Fusarium solani fungus on moldy sweet potatoes
- 4-hydroxymyoporone hepatotoxin produced by potato and converted to pneumotoxin 4-ipomeanol by fungus
- toxin ingested and carried to lungs
- Clara cells convert to reactive metabolite
- damage to clara cells and pneumocytes (similar to ABPEE)
Perilla Mint Toxicity
- ketone toxin similar to 4-ipomeanol in sweet potatoes
- mature cows most commonly affected
- seed/flower most toxic
Acute severe exposure to what gases can cause ARDS
Ammonia H2S CO2 Methane Nitrogen dioxide (silo gas) Zinc oxide Smoke inhalation
Milk Allergy
- sudden onset urticaria, diarrhea, resp. Distress, pulm. Edema at end of lactation
- hereditary in Channel Island breeds
- type I hypersensitivity to casein
- tx: antihistamines, corticosteroids, milk the cow
Hypersensitivity Pneumonitis
- Allergic resp. Dz due to inhalation of organic dusts containing spores
- usually in older housed animals during the winter
- chronic progressive dz
- Type III hypersensitivity rxn
- CS: increased expiratory effort, resp. Distress, depression, wt. loss
- Dx: CS, TTW, Ab to M. Faeni?
- Tx: remove moldy hay, steroids in severely affected individuals
Parasitic Pneumonia (Cattle)
- Dictyocaulus viviparus trichostrongylid nematode
- affects cattle
Path. Of Dictyocaulus viviparus
-penetrate SI, migrate via lymphatics to pulmonary vessels –> eosinophilic exudation, plug airways, alveolar collapse –> mature lungworms reach bronchus
Gradual recovery in most animals, then re-exposure in adults with partial immunity –> resp. Distress
Dx of Dictyocaulus viviparus
CS
Demonstration of L1 during patent stage (Baermann)
Eos in TTW during pre-patent stage
Tx of Dictyocaulus viviparus
- remove from infected pasture
- dewormers (levamisole, fenbendazole, ivermectin)
Ascaris suum larval migration
- cattle on pasture w/ swine
- CS: fever, cough, tachypnea
- Dx: Hx, TTW
Upper resp. Conditions of Small Ruminants
- fungal granulomas
- necrotic laryngitis
- retropharyngeal LN abscessation (Corynebacterium)
- pharyngeal trauma
- sinusitis
- enzootic nasal tumors
- viral resp. Dz
- Bacterial pneumonia
- parasitic pneumonia
Sinusitis in SR
- Caused by Oestrus ovis fly larvae
- sheep > goat
- CS: profuse nasal d/c, violent sneezing
- Tx: ruelene aerosol, ivermectin
Enzootic nasal tumors
- caused by retroviruses (ENTV)
- leads to adenoma, adenocarcinoma, adenopapilloma
- horizontal trans. Possible
- not in cattle
- sheep > goats
- CS: stertor, discharge, epistaxis, anorexia, asymmetry
Acute viral respiratory diseases of SR
- Bluetongue
- PI-3
- ORSV, CRSV
- Adenovirus
- Caprine HV
CHRONIC viral resp. Diseases of SR
Caprine arthritis encephalitis (CAE)
Ovine Progressive Pneumonia (OPP)
Pulmonary adenomatosis
Caprine arthritis-encephalitis (CAE)***
- caused by nononcogenic lentivirus
- spread by horizontal transmission in colostrum/milk mainly*** (also direct contact, aerosol, fomites)
- kids –> encephalitis
- young adults –> arthritis
- older adults –> pneumonia
- no tx
Ovine Progressive Pneumonia
- nononcogenic retrovirus/lentivirus
- similar to CAE
- long incubation period
- death
CS of OPP
- inc. RR
- good appetite but losing weight
- progressive resp. Failure
- lymphocytic mastitis
- posterior paresis
- arthritis
- vasculitis
Ddx of OPP
- bronchopneumonia
- Ovine pulmonary adenomatosis
- verminous pneumonia
- Corynebacterium
Dx and path of OPP
- CS/Hx
- serology confirms
- PCR, virus isolation
Path: grossly enlarged, heavy, grey/brown spotted lungs with lymphoid infiltrates into alveolar walls
Prevent. Of OPP
- cull seropositives
- isolate lambs at birth and feed bovine colostrum or from OPP free ewes
Parasitic pneumonia in SR
- Dictyocaulus filaria
- Protostrongylus rufescens*
- Muellerius capillaris* - most common, least deadly
- = IH required (snail)
Pulmonary Adenomatosis aka Jaagsiekte dz
- affects mature sheep
- JRSRV
- CS: wt. loss, tachypnea, cough, nasal d/c with death occuring in first few months
- often occurs simultaneously with OPP
- simultaneous
- dx by PCR (but not sensitive when they aren’t clinical)
- difficult to control
- clinical animals shed a lot of virus
Bacterial pneumonia in SR
- similar to bovine resp. Dz complex
- env. Factors, viruses, Mycoplasma, and bacteria all interact
- C. Pseudotuberculosis –> lung abscesses
Mycoplasma pneumonia in SR
M. Ovipneumoniae –> mild in sheep/goats
M. Mycoides –> fever, polyarthritis, peritonitis, pericarditis in goat kids**; mastitis in adults w/ poor prognosis
