Thursday, January 8, 2009

Sneezing rats

This is Potato who presented for sneezing. She is a beautiful rat with a big personality. Its very rare to get a definitive diagnosis for airway disease in rats. Exotic DVM Barbara Deeb wrote a paper a few years ago citing a North American serological study which found that 94 per cent of healthy rats were positive for cilia-associated respiratory bacillus, and 93 per cent for Mycoplasma pulmonis. So vets who see rats can safely assume that most actually started out with chronic respiratory disease...and have a high likelihood of developing lung abscesses secondary to bacterial infection.

Quinolones and chloramphenicol can be used to treat mycoplasmas, corynebacteria, straph/strep and gram negative bacteria in rats BUT quinolones are toxic to cartilage in growing animals and chloramphenicol is toxic to bone marrow (it can cause bone marrow suppression).

Deeb comes up with a controversial estimate that every quality day of rat life is worth the equivalent of around a month of human life...I'm not sure how she came to this figure, but I think what she means is that as long as they aren't suffering it is worth treating them.

She gives a "rescue shot" to rats with severe respiratory disease: 0.2mg dexamethasone +5mg aminophylline (bronchodilator) + 4.5mg enrofloxacin + 2-3ml saline via injection SC every 3-4 days.

For Potato and other less severely affected animals my first drug of choice is doxycycline, although dosing is controversial as there are no drugs registered for use in pet rats in Australia that I know of...meaning that every prescription is "off label." I find that these animals are not cured but their symptoms are reduced and they may improve clinically for a period of time.