TABLE 2.

Summary of average clinical respiratory disease scores of pigs by group after inoculation with PRRSV, M. hyopneumoniae, or both

Group	Scorea at:
	Day 1–3b (n = 20)	Day 4–10 (n = 14)	Day 11–14 (n = 8)
A	0.8 ± 0.4 B	2.4 ± 0.7 A	4.1 ± 0.5 A
B	1.6 ± 0.4 A	2.4 ± 0.5 A	3.7 ± 0.6 A
C	2.2 ± 0.8 A	2.6 ± 0.5 A	2.9 ± 0.6 B
D	0 D	0 C	0 C
E	0 D	0 C	0 C
F	0.6 ± 0.3 C	1.9 ± 0.4 B	2.1 ± 1.4 B
G	0 D	0 C	0 C

^aScores: 0, normal; 1, mild dyspnea and/or tachypnea when stressed; 2, mild dyspnea and/or tachypnea when at rest; 3, moderate dyspnea and/or tachypnea when stressed; 4, moderate dyspnea and/or tachypnea when at rest; 5, severe dyspnea and/or tachypnea when stressed; 6, severe dyspnea and/or tachypnea when at rest. Within each column, values followed by different letters (A, B, C, or D) are significantly different from each other (P < 0.001). 

^bPigs were 6 weeks old at day 0.