TABLE 2.

IgGa-to-IgGb and IgGa-to-IgGT ratios for mean IgGa-, IgGb-, and IgGT-associated antibody to each of the R. equi Vap proteins for each horse group

Group and ratio	Value of ratio for:
	VapA	VapC	VapD	VapE	VapF	VapG	VapH
IgGa/IgGb
Healthy adults	1.89 ± 0.61	1.76 ± 0.94	—a	—	1.27 ± 0.45	—	1.04 ± 0.91
Pneumonic foals	1.01 ± 1.75	0.50 ± 1.66	0.37 ± 0.85	0.53 ± 1.31	0.35 ± 0.91	0.35 ± 0.94	0.50 ± 1.24
Healthy foals	1.30 ± 0.94	1.56 ± 0.94	0.00 ± 0.00	—	0.62 ± 0.91	0.67 ± 0.94	0.47 ± 1.36
Significanceb	ac	ab	—	—	a	b
IgGa/IgGT
Healthy adults	2.57 ± 0.88	—	0.56 ± 0.77	—	3.75 ± 0.44	—	2.62 ± 0.44
Pneumonic foals	0.95 ± 1.07	1.10 ± 0.72	—	—	—	0.62 ± 0.78	—
Healthy foals	1.35 ± 0.50	5.49 ± 0.98	—	—	—	1.25 ± 0.79	4.90 ± 1.64
Significanceb	ac	b

^aDashes indicate an inability to calculate the ratio due to the absence of a response and hence a zero denominator.

^bSignificant differences (P ≤ 0.05 by Student's t test) between the adult and pneumonic foal group are indicated by a, those between the pneumonic and healthy foal groups are indicated by b, and those between the adult and healthy foal group are indicated by c.