CAL: Farm animal diagnostic techniques Flashcards
When can you use BALV in farm animals?
tolerated in all but the most dyspnoeic patient, consider for diagnosis of BRDC.
Name the 3 BALV techniques
endoscope, trans-tracheal sampling and nasal tube sampling
Which animals should be selected for BALV?
sample as early as possible in disease outbreak, no CS but temperature >39.5 degrees. If marked mucopurulent nasal discharge the inflammatory process may be too advanced to yield appropriate cells for detecting virus by FAT.
Is BALV a surgical procedure?
No
Method - BALV
Fill a 50ml syringe with sterile PBS and flush into lung. Wait 20 seconds or so until lavage fluid is aspirated. This will retrieve a frothy, slightly cloudy sample (10-30ml).
Where does the BALV tube always end up? What is the effect of this?
Tube always locates in the right diaphragmatic lobe. This is a disadvantage for infectious respiratory disease as the anterior lung lobes are the initial sites of the disease process. Doesn’t seem to be a problem in clinical practice as despite gross lesions in the diaphragmatic lobes, cellular changes observed would still indicate viral infection. Other disease (parasitic pneumonia), sampling here is of positive benefit.
How quickly do you get the results for viral FAT?
very quickly - can be next day. also very specific
Cytology - early BRDC
multinucleated syncytia frequently present
What does a high temperature of 40 degrees in calves suggest?
supportive of a viral infection - FAT and/or paired serology would confirm this.
Tx- outbreak of BRSV
NSAID +/- intranasal vaccine
What indicates bacterial involvement in a respiratory infection?
pus in nose - then treat calves with AB
What are the 2 best ways to prevent BRDC in calves on a farm that has suffered from this problem previously?
‘Vaccinate and booster calves against RS (+/- other respiratory pathogens) before weaning.’ and ‘Optimise stocking density and ventilation at housing.’
