TABLE 4.

Spleen weights and antibody titers against B. abortus RB51 in vaccinated and infected mice

Vaccination route	Challenge route	Spleen wt (mg)	Log antibody titer
Oral	Oral	301 ± 145	1.6 ± 0.2
Intraperitoneal	Oral	233 ± 99	1.9 ± 0.3
None	Oral	273 ± 68	Negative
Oral	Intraperitoneal	206 ± 74	NDb
Intraperitoneal	Intraperitoneal	151 ± 27c	ND
None	Intraperitoneal	284 ± 139	ND

^aMice were infected with B. abortus 2308 42 days after vaccination. Spleen weights and antibody titers were assessed at 18 days after challenge infection. Data are mean values for five animals ± standard deviations.

^bND, not done.

^cStatistically different (P ≤ 0.05).