Smith 5 - Ruminant Resp Flashcards
enzootic nasal granuloma
-cattle and sheep
-allergen irritates first, then subsequent irritation causes granuloma growth
-chronic yearly / seasonal problem
-itchy, discharge, resp obstruction
majority of neoplasms in sheep and goats
adenopapillomas, adenomas, or adenocarcinomas
ONAV / CNAV
enzootic nasal adenocarcinoma
-young adults
-progressive
OPA
ovine pulmonary adenocarcinoma
-jaagsiekte sheep retrovirus
oestrus ovis
nasal passage / sinus parasite
-discharge, sneezing, rubbing
-sneeze out adult worms, turn to flies
-Tx: oral ivermectin
sinusitis is often associated with
dehorning
-frontal sinus
-t pyogenes
cause of sinusitis, not dehorning related
p multocida
necrotic laryngitis / calf diphtheria
-f. necrophorum enters through contact ulcers
-crowded feedlots, <30 days old
-most cases 1-18 months old
Tx for calf diphtheria
oxytet, PPG, florfenicol
+ NSAIDs
laryngeal papillomatosis
-papoviruses
-enter through contact ulcers
-frondlike yellow pedunculate on vocal cords
-sx removal
arytenoid cartilage abscesses
t. pyogenes
-calves and sheep
-alert and afebrile
idiopathic tracheal collapse in cattle
caudal cervical / cranial thoracic
DV flattening
tracheal edema syndrome
-feedlot cattle
-edema and hemorrhage in dorsal tracheal wall
-honker cattle, nonproductive cough
-can cause acute dyspnoea in heavy feedlot cattle
-chronic form in lighter cattle
pathogenic organisms invade the lung through the pulmonary tree
bronchopneumonia
CS: depression, fever, signs of sepsis, A-V distribution of abnormal lung sounds and lesions
bronchopneumonia
interstitial reaction to inhaled allergens
interstitial pneumonia
septic emboli from liver abscesses or postcaval thrombi to the lungs
metastatic pneumonia
CS: sepsis and bronchopneumonia, hemoptysis
metastatic pneumonia
Respiratory Dz Complex
broncho or pleuropneumonia
-enzootic pneumonia in dairy cattle
-shipping fever in beef
IBR
BHV-1
-can have conjunctivitis / keratitis
-2ary bacterial infection common
-adult cattle are the reservoirs
BRSV
-CV distribution
-disease limited to resp system
-rapid progression
PIV-3
mild / may be asymptomatic but contributes to other agents
mannheimia hemolytica
-gram neg aerobe
-serotype A1 most common
-dull, depressed, off feed at first
-pleural pain, loud harsh CV sounds, NO COUGH
-fibrinous pleuritis = abducted elbows
-often viral infection occurs first
–> endotoxemia
pasturella multicoda
-serogroup A
-does cause cough
-endotoxemia
-less severe and shorter dz than MH
-common in young calves with bronchopneumonia
histophilus somni
-does cause cough, pleural pain
-LOS (acts same as LPS – endotoxemia0
-vasculitis and thrombi
m. bovis
cattle only
-outbreaks in calves
-can also get otitis / vestibular signs
-arthritis / tenosynovitis
-pneumonia that doesn’t respond to usual therapy
-need to culture TTA
BHV-1 resp dz mechanism
1) direct injury and destruction of infected URT cells, inflammation, increased susceptibility to infections
2) immunosuppression
+ can have latent infections
main reservoir of BHV-1
latent infections
Malignant catarrhal fever
-sporadic dz of cattle
-ovine herpesvirus type 2
BVDV
can cause mild resp dz by itself, or alter immune response / suppression
PI calves fail to respond to vaccines
cattle get influenza ___
IDV
drugs labelled to tx m. bovis
tulathromycin, florfenicol, enrofloxacin, gamithromycin
mycoplasma mycoides capri
-non infectious in adult goats
-mortality in kids 2-8 weeks old
-peracute illness, CNS dz, or acute joint infection and pneumonia
shipping fever causes
fibrinopurulent bronchopneumonia
Vx recommended for feedlot cattle
BHV-1
BVDV1,2
BRSV
PIV-3
8-way clostridial
m.h. + p.m.
metaphylaxis abx
-about to be or just got sick
-recommended to inject individually
4 types of interstitial pneumonia
1) ARDS
2) hypersensitivity
3) chronic
4) parasitic
fog fever
ABPEE - acute bovine pulmonary edema and emphysema
pulmonary adenomatosis
ARDS of adults
feedlot acute interstitial pneumonia
feed pneumotoxins + BRSV ?
- or - bacteria?
-found dead in pen
-mostly heifers
-NO type II pneumocyte proliferation
moldy sweet potato
f. solani (fungus) produces the hepatotoxin 4-hydroxymyoporone, which is then converted to the pneumotoxin 4-ipomeanol
-dyspnoea, frothing, grunting
-signs appear within 1 day of exposure
-deaths 2-5 days later
- grave prognosis, can try flunixin and furosemide
–does NOT affect nursing calves
perilla ketone toxicity
-square stem weed with serrated leaves
-august to October
-adults worse affected»_space; yearlings and calves
-animals found dead, severe dyspnoea, expiratory heave / grunt
-no tx
–similar to APBEE
extrinsic allergic alveolitis
hypersensitivity pneumonitis
-confined adult cattle
-can be chronic, no fever or consolidation
-moldy hay and winter housing
chronic interstitial pneumonias
-fibrosing alveolitis
-bronchiolitis obliterians
-individual animal dz
chronic progressive pneumonia in sheep
OPP and corynebacterium pseudot. abscesses
chronic progressive pneumonia in goats
CLA, CAEV
Ovine Progressive Pneumonia OPP
AKA maedi-visna
-lentivirus
-spread in milk
-chronic / progressive wasting, resp dz, arthritis, neuro dz, mastitis
-prolonged incubation, most cases subclinical
-no treatment, eradicate from flock
OPA / jaagsiekte
-induces pulmonary carcinoma
-retrovirus
- RESP SPREAD
-mature sheep 2-4yrs
-weight loss, exercise intolerance, dspneoa, crackles
-WHEELBARROW TEST for frothy, clear to milky to pink fluid accumulation
-no tx - cull
testing difficult
CAE
caprine arteritis and encephalitis
-lentivirus
1) leukoencephalomyelitis kids 2-6 months
2-4) polysynovitis, mastitis, or interstitial pneumonia in adults
-silent pneumonia found on PM
CLA
c. pesudotuberculosis
-chronic pyogranulomatus abscesses in LN and organs
-external or internal forms
-goats = external LNs
-sheep = internal LNs and organs
–> SHITest (serology)
lungworm in cattle
d. viviparous
-trichostrongyloid nematode
-direct lifecycle
-eosinophilic exudate reaction to L4 in small airways
- prepotent phase d7-25, gradual onset coughing and tachypnea
-patent phase d25-55 consolidation and pneumonia
lugworm tx in cattle
levamisole, fenbendazole, ivermectin, eprinomectin, doramectin, moxidectin
lungworm in sheep / goats
m. capillaris: most common, mollusk host
d. filaria - direct Lcycle
p. rufescens - mollusc, subclinical infections
lungworm tx sheep
moxidectin
*resistant to levamisole
lungworm tx goats
fenbendazole, ivermectin
bovine TB
m. bovis
-transmission by direct contact with infected animals, mostly wildlife
-slowly progressive, non specific, moist cough
-lesions in lungs and pulmonary LNs – GRANULOMAS
-tuberculin skin test
-gold standard = culture (8 weeks)
CVCT metastatic pneumonia
-septic conditions, especially liver abscesses caused by rumenitis, cause vena cava thrombi
-these then spread to lungs
-mostly feedlot cattle, any age
-increased HR RR, dyspnoea, cough, hear murmur, anemia, wheezes, epistaxis
most common cause of diaphragmatic hernia in ruminants
hardware / TRP
histophilus somni vaccination
+ can decrease morbidity / mortality in groups where there are problems
- can cause hypersensitivity reactions after a booster or infection
m. bovis can cause
pneumonia
resp dz
arthritis
tenosynovitis
mastitis
otitis
conjunctivitis
sinusitis
myocarditis
pericarditis
repro failure
m. bovis in young calves
resp + otitis: ear drooping, purulent aural discharge, facial paralysis+ vestibular C
m. bovis in weaned calves
resp + arthritis and tenosynovitis - CPPS
m. bovis DX
tissue culture or deep nasal swab
IHC, immunofluorescence, PCR
serology no good
m. bovis TX
fluoroquinolones
Labelled in the US: Tulathromycin (draxxin), Florfenicol (Nuflor), Enrofloxacin (Baytril), Gamithromycin (Zactran)
mycoplasma mycoides mycoides
-goat kids: normal 2-8 days, then high fever and die
-opisthontonos
-hot swollen joints, pneumonia
-large outbreaks
-does: arthritis, mastitis, interstitial pneumonia
-can isolate from milk tank or animals
-no Vx
-recovered does will be chronic shedders
-control: heat tx colostrum, pasteurize milk for 1 month, cull all kids w swollen joints
Fibrinous pleuritis + necrosis of the lung (brown to grey, firm) w/ infarcts
M.haemolytica, H:somni or Biberteinia trehalosi
BP w/ firm collapsed lobules without fibrin on the pleura:
P.multocida, M.bovis, other mycoplasmas., BRSV, PIV-3.
Nasopharyngeal Swabs
identification BHV-1, BRSV, BVDV (significant) vs. pasteurellaceae: less significant
When can corticosteroids be used?
necrotic laryngitis or tracheal edema syndrome: dex or isoflupredone acetate
ARDS
CS: Sudden onset of severe dyspnea
Gross Path: consistent w/ AIP: fail to collapse once thorax opened, firm rubbery texture, interlobular or bullous emphysema, sometimes edema, sometimes patchwork lobular appearance
Histo Path: alveolar hyaline mb formation and fibrin deposition, alveolar and interstitial edema, type II pneumocyte proliferation
Acute Interstitial Pneumonia
typical pathologic changes characteristic of the clinical picture of acute respiratory distress syndrome
APBEE
AIP
-ARDS in adults >2yo, cows
-moved to lush green pasture (alfalfa, kale, rape, turnip)
-2 weeks after change
-conversion of L-tryptophan into pneumotoxic 3-methylindole compound
-no cough, no sepsis, lungs sound ok
-severe acute dyspnoea
-loud expiratory grunt
-frothing, open mouth breathing, head and neck extended
-mild exercise = collapse and die
-occurs in the fall
-no Tx - 30% die
- can give monensin before turnout
3-methylindole
fog fever
-pneumotoxic → pulmonary edema, alveolar epithelial hyperplasia, hyaline membranes, emphysem
L-tryptophan converted by ruminal microorganisms → indole acetic acid → 3-MI → blood → metabolism by cyt. P450 → alters oxidase system in Clara C and type I pneumocyte → reactive intermediates → detoxified by conjugation w/ glutathione → bind to intraC prot or molecules → cellular damage or death → degeneration, necrosis, exfoliation of clara and type I pneumo C, edema → hyaline mb formation, proliferation of type II pneumocytes (ADENOMATOSIS) + clara C
Nitrogen Dioxide Gas
CS: cough, ↑FR RR, resp grunting, depression, anorexia, agalactiae, extension of head, open mouth breathing, fever, salivation, lacrimation, SQ emphysema, decreased lung sounds and crackles
• DDX: other ARDS syndromes, hypersensitivity pneumonia, nitrate toxicity
• Clinpath: MetHb peak at 30min after exposure, normal in 12-24h
• Pathophys: dissolution of NO2 in water (resp tract) → nitric acid + nitrates + nitrites → MetHb
• Epidemio: outbreak, housed cattle proximity to silo or poorly ventilated. NO2 heavier than air: on top of the silage or at the bottom. Levels highest 48h after filling silo, dangerous up to 3 weeks.
• Necropsy: hyperemia upper airways, hemorrhage, froth trachea, distended non-collapsing lungs w/ rib imprints, patchwork , emphysema and bulla
• Tx: ventilation, outside. Corticosteroids: unconfirmed, furosemide and AB to control secondary bacteria
what is the primary target of immediate / type I hypersensitivity
the lung
bronchiolitis obliterans
Yearling and young cattle
• Deep cough, tachypnea, expiratory effort, no fever
• Hypotheses: sequela to BRSV or PIV-3 or IVR or Dyctyocaulus viviparus of hypersensitivity
• Lung normal on necropsy but don’t collaps
dictyocaulus viviparus life cycle
Direct life cycle: female produce larvated eggs → hatch in the lungs → larvae up to respiratory tract, coughed up → GI → feces → L1 to infective L3 on the ground (≈5 days, varies depending on environment) → ingested by cattle → GI tract, intestinal wall → mesenteric LN: L4 → blood and lymph all the way to lungs (terminal capillaries of the ventral parts of the caudal lobes → immature adult stage (7days after ingestion) → develop and mate → eggs in bronch
PPP 7-25 days
dictyocaulus viviparus DX
• Only nematode producing larvae found in the feces: diagnostic. Rectal samples preferred to limit ground contamination
• Baermann test, may be seen on TTA. Large larvae 400µm w/ pointed tail (≠D.filaria)
• ELISA in serum and milk (from 30 to 138 days post exposure even when BV treated and not shedding).
• Eosinophilia (peak 4-7 weeks after infection)
dictyocaulus viviparus
• L4 in the alveoli → eosinophilic exudate → blocks small bronchi and bronchioles → atelectasis of lobule → cough and tachypnea to compensate: PRE-PATENT
• L4 then mature and migrate up the airways
• Adults → inflammation in larger airways Aspirated eggs and larvae → macrophage and giant C response caudal lobes → consolidation: PATENT
• Complications at any phase: edema (heart failure or epithelial damage), interstitial emphysema (from dyspnea), alveolar epithelial hyperplasia, secondary bacterial infection (uncommon)
• Re-infection syndrome: No larvae are found in the feces. CS due to immune reaction to migrating larvae, even if the animal is immune to the dz.
• Temperate areas w/ high rainfall. Rarely outbreaks in the US but to dry summers: limit survival and accumulation of larvae on pasture.
dictyocaulus viviparus TX
• Levamisole, Fenbendazole, Oxfendazole, Albendazole, Ivermectin, Eprinomectin, Doramectin, Moxidectin (pour-on only).
• Macrocyclic lactone have residual activity
• Dyspnea, fever, anorexia, depression: guarded prognosis
• Control: pasture management and anthelmintics (specific programs in Europe)
• Long action alternatives: continuous release ivermectin or fenbendazole bolus, LA moxidectin injection (120d), and Oxfendazole pulse release bolus. Not available US.
• Suppressive programs can interfere w/ development of immunity but immunity still occurs.
• Delay of spring turnout: adjunct to control
Dictyocaulus filaria
sheep/goats
• Life cycle identical to D.viviparus. Pre-patent: 4 weeks.
• DDX: progressive viral pneumonias.
• Dx: Baermann. Fresh feces, ↓ if stored.
• Larvae have anterior knob ≠ D.viviparus.
• Dorso-caudal regions of diaphragmatic lobes.
• Levamisole, fenbendazole, ivermectin and moxidectin can be used.
• Move animals to fresh pastures if outbreak.
Muellerius capillaris
GOATS!
interstitial pneumonia: firm lungs, diffuse thickening of septa, alveolar epithelial hyperplasia far beyond the immediate surroundings of the parasite. No nodule
• Indirect cycle:
L1 coughed up and swallowed → feces - Resist several month in environment - Intermediate molluscan host → development of L3 in 12 days - Ruminant ingests the snail → L3 goes to mesenteric LN → L4 - L4 migrates to the lungs → adults develop in alveoli
• Dx Baermann. Kink at the end : characteristic
• Pre-patent 6 weeks.
• Moxidectin in OV. Fenbendazole, albendazole, oxfendazole and ivermectin CP.
• (!) resistant to levamisole (!) albendazole caution first 35d of pregnancy (possibly teratogenic)
Dx Testing for OPP / MV
serology to identify carriers
AGID - specific
ELISA - sensitive, can screen milk
Seroconversion 3wks - 1 yr
pneumonia associated with septic TE most associated with
CAUDAL vena cava
feedlot cattle >1yo
rumenitis
Respiratory signs + anemia + widespread wheezes + hemoptysis = pathognomonic
–neutrophilic leukocytosis w/ regenerative left shit, ↑ globulins, ↑ liver enzymes.
–Chest X rays: irregular density, hematoma, gas-fluid interfaces or consolidation
Bovine TB CS
Usually slowly progressing, CS late in the course (non specific).
-Mild respiratory signs, soft moist cough. Obvious dyspnea, emaciation and resp distress when advanced stages
LN related:
-Enlarged → rupture and drain.
-Bloat if mediastinal LN.
-Dysphagia-stridor-salivation if retropharyngeal
-Intestinal obstructions in mesenteric LN
TB Testing
• primary screening with single injection of M.bovis PPD (tail of neck depending on country)
• primary or confirmatory test: dual injection of M.avium and M.bovis PPD to separate neck areas
• Varies regionally, various nontuberculous mycobacterium spp. can confound interpretation.
do cattle have a complete mediastinum?
yes
OvLV’s
ovine lentiviruses
maedi visna + OPP
CAEV
how to test to SRLVs / maedi visna / OPA
elisa or pcr on bulk tank
elisa, agid, or pcr animals
how to test for OPP / jaagsiekte
histo and IHC only
