Table 1.

Experimental mouse groups, interventions and culture results

Experimental Mouse Group	Number	Immunosuppressed	Ureaplasma parvum challenge	Positive culture			P value*
				Blood	Lung	Peritoneal cavity swab
Normal control (immunocompetent, uninfected)	12	No	No	NA	NA	NA	0.16
Immunosuppressed control	12	Yes	No	0	0	0	0.42
IT/IP challenged immunocompetent control	12	No	Yes	0	6	5	0.47
Vehicle IT/IP negative control1	16	Yes	Spent broth	0	0	0	Reference
IT/IP challenge2	19	Yes	Yes	0	13	9	0.0008
IP challenge3	20	Yes	Yes	0	0	8	<0.0001

IT, intratracheal; IP, intraperitoneal; NA, not applicable

^*P value for ammonia concentrations compared to spent vehicle broth

¹Two deaths prior to experimental endpoint (days 10 and 12), attributed to anesthesia and IT challenge.

²Eight deaths prior to experimental endpoint. One mouse died on day 11 after having been noted to feel cool to touch. One mouse developed bladder enlargement and died after immunosuppressive drug administration on day 11; it was not possible to assess its ammonia level but blood and bladder aspirate cultures were positive. One mouse was sacrificed on day 11 because of tachypnea, hunched stature and lethargy; cultures of blood, lung and a peritoneal swab were positive and ammonia was 955 μmol/L. Four mice died after IT/IP inoculation on day 12, of which two developed an enlarged bladder and died about 15 minutes after IT/IP inoculation with ammonia levels >1000 μmol/L and positive blood and bladder aspirate cultures. One mouse was sacrificed on day 12 because of tachypnea, hunched stature and lethargy; cultures of lung and a peritoneal swab were positive and ammonia was 326 μmol/L.

³One death just before sacrifice on day 14; the animal had hunched stature and lethargy after inoculation on day 13.