Table 1.

Ability of F. columnare strain to receive pCP29 by conjugation with E. coli S17-1.

Strain	Results of mating attemptsa	Virulence in channel catfish
C#2	++	High
AL-203-94	++	High
Fc14-56	-	Unknown
94-060	++	High
1191-B	+	High
94-078	+	High
94-081	++	High
90-059	-	Low
L90-659	++	Low
92-002	-	Low
C91-20	++	Low

^aTransconjugates isolated at an efficiency equivalent to that achieved with C#2: ++; Transconjugants isolated but at low efficiency: +; no transconjugants isolated: -.