URT-Nasal, Pharyngeal and Laryngeal Diseases of Cattle Flashcards
Nasal granulomas and allergic rhinitis is sporadic and rare. Imagine what a cow with this disease would look and sound like if she presented to you.
Nasal granulomas are caused by most mycotic and bacterial pathogens and all of them are rare. It is an uncommon condition. Animals will present with disruption of normal airflow due to the nasal granuloma.
Describe a nasal granuloma lesion.
This is a localized granuloma within the nasal cavity that will cause granulomatous inflammation, nasal discharge, and impaired inspiration.
What are the clinical signs seen with nasal granulomas?
It is centered on disruption of normal airflow.
Upper respiratory noise- stridor
Inspiratory dyspnea which can be exasperated by heat and dust.
Serosanguenous or bloody nasal discharge- unilateral
Epistaxis
Single or multifocal lesions located anywhere in the nasal cavity
How to diagnose nasal granulomas?
If you can see it –> biopsy it because then you can diagnose it,Culture or histopath will reveal hyphae or sporidium
TX: Sodium Iodide 66 mg/kg IV, Repeat every 6 weeks until signs of iodism (watch out for anaphylaxis)
- can also do intralesional injection with antifungals or antibiotics to avoid systemic issues
What are signs of iodism?
flaky skin, alopecia, ropey nasal discharge
Treat them right before toxicity, usually 3-4 TX
Allergic rhinitis can become?
enzootic nasal granuloma
What causes allergic rhinitis?
Allergic reaction against a plant pollen or a fungal spore resulting in nasal inflammation
What is the pathophysiology difference between allergic rhinitis and enzootic nasal granuloma?
Allergic rhinitis is due to acute exposure and is a mast cell and IgE mediated inflammation (Type 1 Hypersensitivity)
Enzootic nasal granuloma is due to chronic damage that induces granulomas, and is macrophage mediated inflammation.
What clinical signs are associated with acute allergic rhinitis and chronic enzootic nasal granuloma?
Acute signs: sneezing, nasal discharge, pruritus, dyspnea, Stertorous breathing, inflamed mucosa
Chronic: many of the same signs as acute but also multiple focal granulomas or plaques throughout the nasal cavity.
Who gets allergic rhinitis?
Channel Island breeds (a few holsteins reported too)
Younger animals (6 months and 2 years)
More common in the summer and in warm moist environments
How does one diagnose allergic rhinitis?
Well it is much like fungal granulomas so biopsy and send it off. Were looking for eosinophils and mast cells.
Also clinical signs!
Granulomas are going to be 1-2 mm and are nodules/plaque like
What therapy will bring the best resolution for nasal granulomas or allergic rhinitis.
Treat an inflammatory mediated disease by controlling the inflammation. USE: Dexamethasone (watch out for pregnant cows because fetal cortisol initiates parturition and Dex mimics this) & Flunixin meglumine IV q 12-24 (not quite as effective)
Other options: Isofluprednisone
Topical corticosteroids
Antihistamines (tripleenamine)
What cell types are associated with acute and chronic allergic rhinitis?
Acute- Mast cells and IgE
Chronic- Macrophages
What NSAIDs are available for use in cattle in the United States? Why should dexamethasone be used cautiously in some cattle?
Dexamethasone and Flunixin meglumine
Dex: watch out for pregnant cows because fetal cortisol initiates parturition and Dex mimics this
What is the single most important predisposing risk for the development of sinusitis in cattle?
Why are bucking bulls most prone to this disease?
Dehorning which opens the frontal sinus and allows debris to collect in the ventral sinuses which is nearly impossible to remove.
Horn tipping occurs in bucking bulls and if tipped too short then it opens up the sinus cavity also theyre more prone to horn trauma resulting in potential for bacterial to enter.
What are the clinical signs associated with the acute phase of sinusitis and the chronic phase of sinusitis?
Acute: fever, nasal discharge-unilateral and mucupurulent, malaise, stridor, anorexia
Chronic (creates dramatic signs): not febrile, nasal discharge, foul odor of the breath, malformation of the face, exophthalmos, neurologic signs (head tilt)
How do you diagnose sinusitis?
thump cows head and it will reveal a dull thud = inflamed sinuses
Presentation is usually obvious and culture is usually meaningless
Note changes in symmetry, nasal, or ocular discharge
Which sinuses communicate in cattle?
In BOVINE there is a cornual diverticulum (Fig. 14B-8), which is an extension of the frontal sinus into the cornual process. Numerous septa divide the BOVINE frontal sinus, one of which almost completely and divides the frontal sinus into a rostral and a caudal compartment.
The maxillary sinus extends into the lacrimal bulla. Dorsal to the maxillary sinus is the dorsal conchal sinus. An infected tooth is the cause of maxillary sinusitis.
How do you know which sinus to trephine and lavage in Sinusitis?
If your percussion of the skull gives you enough evidence to isolate it to one area, then you will drill a hole in the frontal or maxillary sinus.
make the most ventral hole so material can drain out
Then lavage, lavage, lavage!!
Antibiotics are indicated – Penicillin is a good choice because anaerobes are frequently isolated.
NSAIDs
What drugs are indicated with sinusitis?
Antibiotics are indicated – Penicillin is a good choice because anaerobes are frequently isolated. –> T. Pyogenes
& NSAIDs
Why is sinusitis so hard to treat?
given the difficulty in cleaning the sinuses, treatment is often long and arduous
SO procaine penicillin G is given often and Flunixin meglumine (NSAID if inflammation is really bad)
What is the best method for dehorning?
Breeding for polledness as the dominant trait (if one parent is the dominant then all the offspring will be polled)
- If you have to dehorn, age makes a difference so do it young and make sure you do it before the keratin is present.
What sets up a calf for developing necrotic laryngitis?
This is also known as calf diptheria for the diptheritic membranes on the arytenoid membranes
Initial damage to the laryngeal mucosa and cartilage from mucosal ulcers caused by upper respiratory viral infections, water deprivation, or contact with toxic chemicals allows infection of F. necrophorum
What is the primary pathogen associated
with this necrotic laryngitis?
Fusobacterium necrophorum ~the baddest anaerobe you’ll ever meet
This is an anaerobic gram -, that causes inflammation due to the production of endotoxin and a leukotoxin. Severe inflammation and necrosis results in the formation of a diphtheritic
membrane over the laryngeal cartilage.
