Table 3.

Indices of immunity (II) induced by BGs variants.

Animals Immunized with BGs/Antigen	Guinea Pigs		Mice
	LD50, CFU *	II **	LD50, CFU	II
….	147 37 ÷ 584	4.9 × 101	32 8 ÷ 126	4.6 × 100
Y-K	6813 2154 ÷ 27123	2.3 × 103	22 5 ÷ 86	3 × 100
E-Y-K	146,780 36,869 ÷ 926,119	4.9 × 104	22 5 ÷ 86	3 × 100
S-R-Rz	68 17 ÷ 271	2.3 × 101	15 4 ÷ 58	2 × 100
E-S-R-Rz	147 37 ÷ 584	4.9 × 101	46 12 ÷ 233	6.6 × 100
F1 **	316 79 ÷ 1259	1.0 × 102	100,000 25,119 ÷ 630,957	1.4 × 104
PBS	3 1 ÷ 13	1 × 100	7 2 ÷ 27	1 × 100

* Values are given as means ±95% confidence intervals. ** The ability of BGs to protect an animal from death after administration of a high dose of a virulent wild type strain, designated Immunity Index (II) was calculated as the ratio: II = LD_50imm/LD_50veh.