Lectures 6-8 Flashcards
How is rhodococcus equi spread
Inhalation from the soil to foal, NOT foal to foal
What are clinical signs of R. Equi
Bronchopneumonia
Extrapulmonary disease
What is the only way to make a definitive diagnosis of R. Equi
Tracheobronchial aspiration- degenerate neutrophils, gram positive coccobacillus
How to treat R. Equi
Macrolide and rifampin
What is pneumonia?
How about pleuropneumonia?
Pneumonia- infection involving lung parenchyma
Pleuropneumonia- pneumonia or lung abscess that extends to and involves the visceral pleura
What infectious agents cause pneumonia/pleuropneumonia
S. Zooepidemicus
Gram negative bacteria
Anaerobes
How to treat pneumonia/pleuropneumonia
Antibiotics, pleural drainage, supportive care, thoracotomy and rib resection
What complications come from pneumonia/pleuropneumonia
Endotoxemia, laminitis, pleural/pulmonary abscesses, pneumothorax, pericarditis
What is exercise induced pulmonary hemorrhage
Presence of blood in the airways after intense exercise from failure of pulmonary capillaries during exercise
How to treat EIPH
Furosemide prior to racing
Doesn’t prevent hemorrhage, but decreases severity
What clinical signs will you see with heaves
Cough, exercise intolerance, abnormal lung sounds, resp distress, increased expiration effort, weight loss
*usually don’t see fever unless complicated by secondary bacterial infection
How to treat heaves
Reduce dust/allergen exposure
Corticosteroids
Bronchodilator
Describe cow lungs
Well developed lung lobes, well developed lung lobulation, small total alveolar surface area, extensive lymph drainage (pleural effusion is rare)
Which lung is bigger in cattle
Right lung- much bigger
What is calf diphteria
Infection of soft tissue of oral cavity and/or laryngeal mucosa
Oral necrobacillosis, necrotic laryngitis
Usually caused by T. Pyogenes and fusobacterium necrophorum
What are clinical signs of calf diphteria
Fever, anorexia, excessive salivation, halitosis, moist painful cough +/- inspiratory dyspnea when larynx is involved
What is the treatment for calf diphteria
Penicillin +/- sulfa
NSAIDS may help
Viral diseases in cattle
Parainfluenza virus type 3 Bovine respiratory syncytial virus Infectious bovine rhinotracheitis virus Bovine viral diarrhea virus Coronavirus
What is the main significance of viral disease in cattle
They kill the cells responsible for ciliary escalator and kill macrophages
It immunocompromises them and sets them up for bacterial pneumonia
How are viral resp diseases transmitted in cattle
Direct contact or aerosolized
Describe PI3
Affects cattle, sheep, and goats;
Have several vaccines
Bovine resp syncytial virus
Affects cattle, sheep and goats
Causes flu-like symptoms and immunosuppression
Diagnoses through rqPCR
BHV1.1
Infectious bovine rhinotracheitis (IBR)
Will see fever, nasal discharge, cough, conjuctivitis, corneal opacities, pustules in nose, hyperemia of nose, abortion, secondar bacterial infection
Can become latent
BRD
Bovine respiratory disease complex
Environmental weather conditions, viral infectious, and stress —>
Impaired pulmonary defense mechanisms —> colonization of bacterial pathogens —> bronchopneumonia
Enzootic calf pneumonia- who does it affect
Calves 2 weeks to 5 months old
Mostly dairy calves
Environmental factors contributing to enzootic calf pneumonia
Inadequate ventilation Inadequate temp and humidity Poor sanitation Overcrowding Noxious gases Dust Failure of passive immunity
Virus factors contributing to enzootic calf pneumonia
IBR, PI3, BRSV (most important), BVD, mycoplasma (can be sole agent)
Bacteria contributors to enootic calf pneumonia
P. Multocida, T.pyogenes, M. Hemolytica, H. Somni,
Strep, salmonella, e coli, pseudomonas
Clinical signs of enzootic calf pneumonia
Fever, cough, nasal discharge, resp distress, bloat, weight loss, large airway sounds in the lungs
How to diagnose enzootic calf pneumonia
Hematology, nasal swabs, transtracheal wash, radiograph/US (best way), necropsy
How to treat and prevent enzootic calf pneumonia
Antibiotics, NSAIDs, nursing care
Can prevent with vx, environmental management (most important), passive transfer
Who does shipping fever complex affect
Young cattle that have recently been shipped to sale yards and feedlots
What are physical risk factors of shipping fever
Abrupt weaning, overcrowding and interaction with cows from other locations, traveling through rough conditions
When would shipping fever complex occur
Peak incidence occurs 7-14 days after arrival at feedlot
What are clinical signs of shipping fever
Stand off by themselves, depressed, decreased appetite, increased resp rate, fever, ocular and nasal discharge, moist cough, dyspnea and death in advanced cases
What main 3 agents causes shipping fever
Manheimia hemolytica
Pasturella multocida
Histophilus somni
What serotype of M. Haemolytica is most commonly isolated in shipping fever
Serotype A1
Growth of serotype occurs in nasopharynx after stress
Histophilus somni- where is it normally located?
What is it a significant cause of in feedlots?
What is different about this vs M. Haemolytica
Normal inhabitant of nasopharynx
Significant cause of pneumonia in feedlots
Can cause bacteriemia and involve other organ systems
How to diagnose shipping fever
Hematology
Imaging
Transtracheal wash
Necropsy
What drugs do you have to avoid when treating shipping fever in feedlots
Aminoglycosides (gentamicin, amikacin, kanamycin)
Chloramphenicol
Excessive doses
How to treat shipping fever
Approved antibiotics
Nsaids (flunixin)
NO steroids
Supportive therapy
How to prevent shipping fever
- Preconditioning- wean, vaccinate, castrate and all those other things 3 weeks before shipping
- Avoid auction yards and overcrowding
- Vaccination on arrival at feedlot if not before
- Antimicrobial therapy on arrival at feedlot (metaphylaxis)
What vaccines should you give to prevent shipping fever
Vaccinate against viral agents
H. Somni vx
M. Haemolytica vx
What is vena caval thrombosis and metastatic pneumonia
Abscessation of lungs caused by septic thromboembolism
- emboli usually originate from caudal venal cava
- commonly occur secondary to ruminitis
Other than vena caval thrombosis, what else can cause metastatic pneumonia
Jugular vein phlebitis
Mastitis
Metritis
Footrot
What are clinical signs of vena caval thrombosis?
Common in feedlot cattle
Weight loss
Hemoptysis
Resp signs with anemia, widespread wheezes, and hemoptysis is pathgnomonic
After hemotypsis there is rapid deterioration
How to treat/prevent vena caval thrombosis
Penicillin but bad prognosis
Need to prevent by slow transition to highly fermentable diets
What is acute bovine pulmonary edema and emphysema
Happens to adult cattle
Atypical, interstitial pneumonia
Called “fog fever”
What are clinical signs of acute bovine pulmonary edema and emphysema
Develops 2-14 days after pasture switch
Acute onset of dyspnea with loud expiratory grunt, open mouth breathing, tachypnea
Normal lung sounds
How to treat/prevent ABPEE
Avoid stress
Nsaids
Prevent by transitioning slowly to new pastures
What is parasitic pneumonia caused by
Dictyocaulus viviparus
Who does parasitic pneumonia affect the most and when does it occur
Cows less than two years of age 1-3 weeks after moving to infected pasture
How to diagnose parasitic pneumonia
Clinical signs and history
Demonstration of L1 during patent period
Eosinophils in TTW during prepatent stage
Peripheral eosinophilia
How to treat parasitic pneumonia
Remove from infected pasture
Levamisole, fenbendazole, ivermectin
What are upper respiratory diseases in sheep/goat
Necrotic laryngitis
Caseous lympadenitis caused by C. Pseudotuberculosis
Bacterial pneumonia of sheep/goats
Similar to BRD
Caused by M.haemolytic
What can cause lung abscesses in sheep/goats
C. Pseudotuberculosis
What can cause parsitic pneumonia in sheep/goats
Dictyocaulus filaria
Protostrongylus rufescens- snail intermediate host
Muellerius capillaris- snail intermediate host
What are the acute viral resp viruses of sheep and goats
PI-3
BRSV
Adenovirus
What are the chronic viral resp diseases of sheep and goats
Ovine progressive pneumonia (sheep only)
CAE (goats only)
Pulmonary adenomatosis (mainly sheep)
When do you usually see ovine progressive pneumonia?
Clinical signs?
Sheep older than 2-3 years
Weigh loss, resp failure, lymphocytic mastits, posterior paresis, arthritis, vasculitis
Death usually within 6-12 months
What are differential diagnoses for ovine progressive pneumonia
Bronchopneumonia
Ovine pulmonary adenomatosis
Parasitic pneumona
C. Pseudotuberculosis
How is ovine progressive pneumonia spread
Horizontal transmission
What are clinical signs of pulmonary adenocarcinoma
Weight loss, tachypnea, coughing, lots of nasal discharge
How to treat pulmonary adenomatosis
There is no treatment- death occurs within first few months of clinical signs
What causes pulmonary adenomatosis in ovines
Jaagsiekte sheep retrovirus