Volume 15, Number 5—May 2009
Dispatch
Human Streptococcus agalactiae Isolate in Nile Tilapia (Oreochromis niloticus)
Joyce J. Evans
, Phillip H. Klesius, David J. Pasnik, and John F. Bohnsack
, Phillip H. Klesius, David J. Pasnik, and John F. BohnsackTable
Mortality rates among Nile tilapia (Oreochromis niloticus) infected with Streptococcus agalactiae*
| Dose (CFU/fish) | No. (%)† deaths |
|---|---|
| Tryptic soy broth (control) | 0a |
| 102 | 3 (30)ab |
| 103 | 1 (10)a |
| 104 | 0a |
| 105 | 0a |
| 106 | 5 (50)b |
| 107 | 3 (30)ab |
*Ten fish per dose group were intraperitoneally injected with human S. agalactiae/fish or tryptic soy broth and observed for 14 days postchallenge at a water temperature of 32°C.
†Superscript letters indicate significant differences (p<0.05) in percentage mortality rates between groups, determined by using the SAS program (SAS Institute, Cary, NC, USA) lifetest procedure (Kaplan-Meier method).
