An atypical weakly haemolytic strain of Brachyspira hyodysenteriae is avirulent and can be used to protect pigs from developing swine dysentery

Table 6 Shedding of weakly haemolytic B. hyodysenteriae MU1 in the faeces of pigs in group A in experiment 3, as detected by culture on selective medium

Pig number	Culture results (days after first day of challenge with MU1)^a								Median
Pig number	8	11	15	18	22	25	29	32	Median
1	0	0	0	0	0	0	0	0	0
2	0	0	1	1	1	1	1	1	1
3	0	0	0	1	1	1	1	1	1
4	0	0	0	0	1	1	1	1	0.5
5	0	0	0	1	1	1	1	1	1
6	0	0	0	0	0	0	0	0	0
7	0	0	0	0	0	1	1	1	0
8	0	0	0	1	1	1	0	1	0.5
9	0	0	0	0	1	1	1	0	0
10	0	0	0	0	0	0	0	0	0
11	0	0	0	1	1	1	0	1	0.5
12	0	0	0	0	1	1	1	1	0.5
Median	0	0	0	0	1	1	1	1	0.5

Pigs subsequently were challenged with a cocktail of 5 virulent strains.
^aCulture score: 1 to 5, extent of growth on selective agar plates; 0, no growth.

ISSN: 1297-9716