FIG. 5.
Macroscopic and microscopic observation of yrp1::lacZ gene expression in fish. Fish were infected by intraperitoneal injection with 103 cells of Y. ruckeri 150RI4 (yrp1::lacZ) and, after death, they were treated with a X-Gal (5-bromo-4-chloro-3-indolyl-β-d-galactopyranoside) solution as described in Materials and Methods. Control fish were injected with the Y. ruckeri wild-type strain 150. (A) Dissected rainbow trout showing the internal organs. The control, 150 strain fish is shown above the strain 150 RI4 fish. Panels B, C, D, and E (left column) show the 150 wild-type strain (control fish) in the left and the 150RI4 strain (yrp1::lacZ) in the right column. (B and C) Macroscopic and microscopic details of gills, respectively. (D and E) Macroscopic and microscopic details of intestine, respectively.