are right or left lungs larger in the cow? is the mediastinum complete or incomplete?
- Right larger (first affected by pneumonia)
- complete mediastinum
what is the significance of having more connective tissue in the septa?
no collateral ventilation so will not reinflate once collapsed
how does alveolar surface area and airflow rate compare to other species?
- alveolar surface area = 50%
- airflow rate = 300% - hi airflow leads to more pathogens transported through lungs
- (smaller lungs overall = reduced heat tolerance and red. resistance to infections)
what is an infectious cause of obstructed airflow that can be treated with ivermectin?
what is a possible non-infectious cause of open mouth breathing in calves?
persistent membrane obstruction
why should you palpate the top of the cow while ausculting the lungs?
ruptured bullae can cause SQ emphysema
How will pleural fluid/mass in pleural space vs. pulmonary edemaaffect ability to hear bronchovesicular sounds?
- pleural fluid/mass: decreased
- pulmonary edema: increased
How will thin vs. thick body wall affect ability to hear bronchovesicular sounds?
- thin: increased
- thick/fat: decreased
How will rapid, deep or labored breathing affect ability to hear lung sounds?
with ultrasound what signs of respiratory disease are apparent? 3
- comet tails - fibrin
- consolidated areas (presence of fluid in lung tissue)
- presence of free fluid (pleural fluid)
what is the best diagnostic test for evaluating the environment in the lung/culture respiratory disease?
what is the best collection method for cytology?
bronchoalveolar lavage (NOT good for culture though)
when are nasal swabs helpful for diagnosis?
when trying to isolate VIRUSES or pure cultures of non-commensals (mycoplasma)
what is the causative agent of mycotic nasal granuloma? who gets it?
- rhinosporidium spp.
- no breed, sex, gender, or season predilection
what are clinical signs of mycotic nasal granuloma
How is it diagnosed?
- epistaxis & nasal discharge
how is mycotic nasal granuloma treated?
- antifungals are illegal in FA
- sodium iodide or surgery
which breeds are more often associated with allergic rhinitis, a hypersensitivity I reaction to plant pollen/fungal spores?
- channel island breeds
what type of weather and what clinical signs are associated with allergic rhinitis?
- warm, moist environment
- intense pruritis
- granulomas + pale pink, flat plaques
- (also stertor, nasal discharge, dyspnea)
what will impression smear of the plaques show with allergic rhinitis? how is this treated?
- antihistamines (not labeled for FA) or steroids/dexamethasone (cause abortions)
what retroviruses are associated w/enzootic nasal tumors? where does neoplastic transformation occur?
- ovine/caprine nasal adenocarcinoma virus
- secretory epithelial cells of nasal turbinates
nasal tumors present with open mouth breathing/dyspnea, discharge and other non-specific upper respiratory signs. How is it treated?
surgical removal - recurs and lots of bleeding at surgery
Sinusitis is more common in cattle than small ruminants. What are some causes? 4
- dehorning (frontal)
- infected teeth (maxillary)
- Tumor/infection (Actinomyces)
- trauma - broken horn,facial fx
At what age does the horn attach to periosteum of the frontal sinus? at what age does the cornual diverticulum open into the horn?
- 2 mo - periosteum
- 6 mo - cornual diverticulum
what are clinical signs of sinusitis? 5
- ADR (lethargy, fever, anorexia)
- Frontal bone distortion
- Nasal d/c
Clinical signs and history are usually enough to diagnose sinusitis. How is it treated?
trephination - flush daily with dilute antiseptic - Penicillin
what are some clinical signs of pharyngeal trauma, as seen with misuse of a balling gun? 6
- Throat edema
- Gas in tissues seen on rads
How is pharyngeal trauma treated?
- Abs + NSAIDs
- Ventral Drainage
- +/- rumenostomy/tracheostomy
when performing ER tracheotomy, should you cut in the cranial, middle, or distal third of the neck? why?
- middle 1/3
- cranial - can damage thyroid or cut into larynx
- caudal - trachea deeper- more dissection/more dead space/infection
What is the causative agent for necrotic laryngitis?
What is another name for this disease?
- fusobacterium necrophorum
- Calf Diptheria
Who is affected by necrotic laryngitis?
- Feedlot calves 3-18mo
- fall and winter
How does fusobacterium necrophorum cause a problem in the larynx since it can not invade intact mucosa?
- Viral (IBR) or bacterial (mannheimia) infection
- Cough & laryngeal ulceration
- F. necrophorum penetrates
- Infection and swelling
Clinical signs of necrotic laryngitis are similar to those of balling gun injuries, but how is this condition treated?
- Oxytetracycline (or sulfas, penicillin)
- NSAIDs (no aspirin since given orally, avoid PO)
what are some secondary complications associated with laryngeal damage?
- Aspiration pneumonia
- Poor doer
Bovine Respiratory Disease Complex is most prevalent after shipping and comingling cattle. How long after shipping do signs typically occur?
7-10 days after moving
what are typical signs of BRDC? 7
- Cough (moist or dry)
- Nasal D/C & Dirty nose
- Foul breath
- Oral erosions
what viral pathogens are associated with BRDC? 4
what bacteria are associated with BRDC? 5
- Mannheimia hemolytica
- Pasteurella multocida
- Histophilus somni
- Mycoplasma bovis
- Arcanobacter pyogens
how does level of fever and type of nasal discharge compare between viruses and bacteria?
- virus: hi fever, serous discharge
- bacteria: mild to moderate fever; purulent discharge
Is animal more likely to be depressed with viral or bacterial respiratory infection?
- bacterial = depressed
- viral = more alert
Which Lung sounds sounds are heard with Viral vs Bacterial Lung
- Bact= Pleural Friction Rub, Crackles & Wheezes
- Viral = Bronchovesicular
Shipping fever causes which type of Pneumonia?
what are the components of shipping fever and cause bronchopneumonia?
- PI3, IBR, BVD
- Histophilus, Mannheimia
what are the components of enzootic calf pneumonia and cause bronchopneumonia?
what are causes of interstitial pneumonia?
Which respiratory virus is herpes 1? where does this virus reside while latent?
- Infectious Bovine Rhinotracheitis (red nose)
- *trigeminal nerve* - reactivated by stress - shed in ocular/nasal secretions
Is IBR more prevalent in feedlots, beef calf/cow, or dairy operations? what age are cattle? how long is incubation?
- > 6 mo
- incubation 2-6 days
what are classic clinical signs for IBR? 5
- high fever
- hyperemia of nasal turbinates/muzzle/hard palate ("red nose")
- "sewer pipe trachea"
- conjunctivitis/corneal edema
Is IBR associated with high or low fatality rates? are abortions associated with IBR?
- low fatality (unless complicated by 2ndary bacteria)
- abortion storms may occur
How is IBR diagnosed?
- virus isolation
- nasal swabs
- fluorescent antibodies
what is treatment for IBR? 3 is there a vaccine?
- Abs to prevent 2ndary bacterial
- supportive (NSAIDs, fluids, etc)
- monitor cornea
intranasal vx during outbreak (interferon); injectable MLV for prevention (within 48 hrs)
What paramyxovirus has high antibody prevalence in feedlots, indicating it is endemic? Does this virus cause problems in young or adults?
- parainfluenza 3
- *young* affected - the older the cow the more protective antibodies
what are clinical signs and necropsy findings for parainfluenza?
How is it diagnosed?
- *mild*non-specific viral signs (cough, fever, tachypnea)
- No specific necropsy lesions
- Most have antibodies, single titers not helpful
what is treatment for parainfluenza? is there a vaccine?
- supportive care
- vaccine for prevention
what paramyxovirus causes severe signs in young by affecting respiratory cilia?
bovine respiratory syncytial virus
what type of pneumonia is associated with BRSV?
- interstitial pneumonia - edematous/heavy wet lungs
- emphysema in dorsum SQ if bulla rupture
Signs associated with BRSV can be severe or animal can be found dead. What are ways to diagnose BRSV ante mortem and post mortem?
- AM: virus isolation, serology, IF on nasal swabs
- PM: interstitial pneumonia, emphasematous bulla, IH
what is tx for BRSV? is there a vaccine?
- Abs if concerned about 2ndary bacteria + dexamethasone (to stop inflammation) or antihistamines (unavailable for cattle)
- vaccine for prevention, highly effective
why should you avoid lush grass and legumes in patients with BRSV?
can lead to "Fog Fever" (synergism with ABPEE)