2.2.1: Respiratory disease in small mammals and exotic species Flashcards
Clinical signs of respiratory disease in small mammals
- Lethargy
- Poor coat
- Anorexia
- Audible clicking
- Sneezing
- Ocular discharge (porphyrin)
- Dyspnoea / abdominal heaving
- Head tilt if middle ear involved
Clinical signs of respiratory disease in reptiles
- Lethargy
- Anorexia
- Weight loss
- Difficulty breathing
- Open mouth breathing
- Wheezes or crackles
- Ocular and/or nasal discharge
- Stomatitis
Clinical signs of respiratory disease in birds
- Lethargy
- Anorexia
- “Fluffed up”
- Crusting around the nares
- Periorbital swelling
- Dyspnoea or tail bobbing
- Voice change
- Tachypnoea
What husbandry questions should you ask the owner of a small mammal with respiratory disease?
- Are they kept inside vs outside?
- Any recent changes?
- Is the environment dusty?
- What is their diet?
- Any new pets?
- Any recent stress?
What husbandry questions should you ask the owner of a reptile with respiratory disease?
- Where are they kept: vivarium vs drawer vs table?
- Temperature?
- Humidity?
- Diet and supplements?
- Any new pets?
- Any recent changes to their environment?
What husbandry questions should you ask the owner of a bird with respiratory disease?
- Where is the cage kept?
- Do you use any sprays / air fresheners?
- Diet?
- UV?
- Any recent changes?
- Any other pets?
What do you need to establish on clinical exam of the exotic pet with suspected respiratory disease?
Localise the problem to:
* URT
* LRT
* Both
* A different system altogether
What diagnostic options are there for the exotic pet with respiratory disease? What would you use each for?
Radiography / CT
* Diagnose abscesses, neoplasia, congestion / consolidation
Endoscopy
* Can take biopsies and locate FBs
Ultrasonography
* Useful for heart scans
Haematology and biochemistry
* Detect inflammatory process, organ damage (e.g. liver in birds)
* Can help determine severity, help with stabilisation
* Could be done pre-GA before imaging
* May be normal despite respiratory tract pathology
PCR testing from swabs
* e.g. for Mycoplasma , herpes
Which swabs can you take from exotic pets and how should you choose?
Aim for whatever will get you a representative sample, using the least invasive technique.
* Deep nasal swab, nasolacrimal duct flush - rabbits
* Nasal flush - birds
* Lesion / oral swab - reptiles
Can also perform BAL/ tracheal lavage at 2ml/kg
Remember bacterial contaminants on swab and interpret appropriately
What are some differentials for respiratory disease in small mammals and which are most common?
- URT bacterial infections
- LRT bacterial infections
- Husbandry: allergies, dust , poor ventilation, stress, poor diet
- Viruses (respiratory or systemic)
- Fungal infection e.g. aspergillosis
- Parasitic e.g. lungworm in ferrets
- Dental disease e.g. rabbits
- Circulatory causes e.g. heat disease and pulmonary oedema, arteriosclerosis
- Trauma e.g. lung contusion
- SOL e.g. tumours, abscesses
- Foreign bodies
Which animals is aspergillosis more common in: indoor or outdoor pets?
Aspergillosis is more common in small mammals kept outdoors
Which animals are foreign bodies more common in: indoor or outdoor pets?
Foreign bodies are more common in small mammals kept outdoors
Common respiratory pathogens of guinea pigs
- Bordetella bronchiseptica
- Chlamydophila caviae
- Adenovirus
What might you see with URT bacterial infections in small mammals?
- Rhinitis
- Conjunctivitis
- Nasolacrimal duct infections
- Otitis media
What might you see with LRT bacterial infections in small mammals?
- Tracheitis
- Bronchitis
- Pneumonia
Common respiratory pathogens of rabbits
- Pasteurella multocida
- Bordetella bronchiseptica
Common respiratory pathogens of rats and mice
- Mycoplasma pulmonis
- Pasteurella pneumotropica
- Strep pneumoniae
- Sendai virus (mice)
Differential diagnoses for respiratory disease in reptiles and which are most common
- URT bacterial infections
- Viruses
- Husbandry issues
- Space-occupying lesions
- LRT bacterial infections
- Fungal infections
- Parasites
- Dental disease
- Trauma
- Foreign bodies
- Circulatory issues (uncommon but possible)
What signs would you see with URT bacterial infections in reptiles?
- Rhinitis
- May also affect structures outside the resp tract: conjunctivitis, stomatitis, periorbital abscesses
What signs would you see with LRT bacterial infections in reptiles?
- Tracheitis
- Bronchitis
- Pneumonia
Which respiratory viruses affect reptiles?
- Herpes virus - tortoises🐢
- Adenovirus - lizards🦎
- Ophidian paramyxovirus (OPMV) - snakes🐍
Which fungal infections affect reptiles?
- Candida
- Aspergillosis
Which parasites affect reptiles?
- Lungworm - snakes🐍
- Rhabdias
- Ascarids
What husbandry issues may play a role in respiratory disease of reptiles?
- High or low temperature
- High humidity levels
- Stress
- Poor ventilation
How can dental disease lead to clinical signs in reptiles?
Periodontal disease can lead to stomatitis
What circulatory issues could cause respiratory signs in reptiles?
- Septic endocarditis
- Congestive heart failure
How coud trauma cause respiratory disease in reptiles?
- Carapace injuries / other injuries could penetrate the lungs
Examples of space-occupying lesions that could cause respiratory disease in reptiles
- Abscesses
- Tumours
- Reproductive disease
- Coelomic effusions
- Granulomas
What differential diagnoses are there for respiratory disease in birds and which are most common?
- LRT bacterial infections
- Fungal infections
- Husbandry issues (allergy, stress, low humidity, poor hygiene / ventilation, hypovitaminosis A)
- Space occupying lesions
- URT bacterial infections
- Viruses
- Parasites
- Circulatory causes
- Foreign bodies
Describe the presentation of URT bacterial infections in birds
URT bacterial infections may cause:
* Rhinitis
* Sinusitis
* Conjunctivitis
Describe the presentation and an example causative agent of LRT bacterial infections in birds
LRT bacterial infections may cause:
* Tracheitis
* Bronchitis
* Airsacculitis
* Pneumonia
Example: Psittacosis (caused by Chlamydia psittaci)
Example of respiratory virus commonly affecting chickens
Infectious Laryngotracheitis
Which fungal infection can often cause respiratory disease in birds?
Aspergillosis
Examples of parasites of birds affecting the respiratory system
Syngamus trachea (gapeworm)
Examples of space occupying lesions that may cause respiratory signs in birds
- Tumours
- Organomegaly
- Reproductive disease
- Obesity
- Rhinoliths
- Pulmonary fibrosis
- Choanal atresia
- Occluding fungal plaques
Inhalation of foreign bodies can cause what in birds?
Can cause granulomatous tracheitis
Generic treatment plan for the exotic pet with respiratory disease
- Oxygen
- Fluids and supportive nutrition
- Nebulisation
- Bronchodilators
- Mucolytics
- Anti-inflammatories
- Treatment for the cause e.g. antibiotics, furosemide, acyclovir, antifungals, antiparasitics, husbandry changes, surgery
True/false: rabbits are obligate nasal breathers, so open mouthed breathing is always an emergency.
True
What aspect of treatment is particularly important to a hindgut fermenter?
Supportive nutrition (consider for e.g. Oxbow Critical Care diet)
In which small mammal should you avoid using steroids if possible?
Rabbits are steroid sensitive so avoid if pos
What medications could you use in the rabbit with respiratory disease?
- Bronchodilator e.g. terbutaline which can be used in a nebuliser
- Mucolytic such as bromhexine which can be given in food
- NSAID e.g. meloxicam which can be given in food / injectable
Which antibiotic would you use to treat Mycoplasma in a rat?
Doxycycline
What antibiotic would be an appropriate first line, broad spectrum choice for the small mammal with respiratory disease?
TMPS (e.g. sulfatrim)
You have a rabbit with an abscess. Which antibiotics will you choose and how will you administer them?
You could use metronidazole + penicillin
BUT the penicillin must be parenteral NOT oral. If you give the rabbit oral penicillin it will die☠️
What rule can you use to help determine safe antibiotic use in rabbits?
PLACE rule
General practitioners should remember the antibiotics that should NEVER be given orally to rabbits by remembering the acronym “PLACE” - penicillins, lincosamides, amoxicillin, cephalosporins and erythromycin!
Source: https://www.vetshow.com/blogs/10-questions-about-zoological-medicine#:~:text=General%20practitioners%20should%20remember%20the,%2C%20amoxicillin%2C%20cephalosporins%20and%20erythromycin!
Why might a macrolide like azithromycin be useful in a small mammal with respiratory disease?
It reduces lung inflammation
When should you use enrofloxacin in a small mammal, reptile or bird?
When you have C&S that supports it!
What reptile-specific considerations should your treatment plan include?
- If malnourished, consider injectable vitamins / liquid dosed supplements in the short term. Long term, still need to improve the diet.
- Vital to keep reptiles at their POTZ for optimal immune system, drug metabolism etc.
- Consider heat and ventilation!
POTZ: preferred optimum temperature zone
Which antibiotic is often used for protozoal and anaerobic infections in reptiles?
Metronidazole
Which antibiotic is a common first line broad spectrum choice in birds and reptiles?
TMPS (Sulfatrim)
Which antibiotic would you use to treat Mycoplasma in a tortoise?
Doxycyline (Karidox)
What avian-specific aspects to your treatment plan should you consider when treating the bird with respiratory disease?
- High oxygen demand
- Fluids and supportive nutrition key - can consider crop tubing
- Nebulisation is very effective due to bird anatomy
- Birds have no diaphragm so LRT clinical signs may be coelomic disease instead (don’t get tunnel vision)
Which antibiotic would you use to treat Chlamydia psittaci ?
Doxycycline
Which antibiotic would you use to treat anaerobic infections in birds?
Metronidazole - but NOT for use in poultry!
It has no MRL so MUST NOT be used in food producing species.
What are some good first line, broad spectrum antibiotic choices in birds?
- TMPS
- Penicillin + co-amoxiclav (arguably this is slightly higher category but sometimes still first line)
