Comparative pathogenesis of type 1 (European genotype) and type 2 (North American genotype) porcine reproductive and respiratory syndrome virus in infected boar

Table 1 Testicular lesion score (TLS), in situ hybridization (ISH), and apoptosis in boars at different days post-inoculation (dpi)

DPI	n	PRRSV	TLS	Number of positive germ cells for ISH				Apoptosis
				Spermatogonia	Spermatocyte	Spermatid	Non-sperm cell
14	3	Type 1	5.9 ± 1.5	1.4 ± 0.8	2.5 ± 0.6	2.0 ± 0.6	1.4 ± 0.4	35.2 ± 1.4^b
		Type 2	6.0 ± 1.4	1.1 ± 0.6	2.1 ± 0.4^a	1.9 ± 0.7	1.4 ± 0.4	28.4 ± 5.8
21	3	Type 1	7.1 ± 1.0	0.9 ± 0.5	1.9 ± 0.5^a	1.1 ± 0.7	1.2 ± 0.3	23.6 ± 7.2
		Type 2	7.2 ± 1.2	0.9 ± 0.5	1.7 ± 0.4	1.3 ± 0.4	1.1 ± 0.7	21.6 ± 6.8
35	3	Type 1	8.5 ± 0.5	0.5 ± 0.7	0.9 ± 0.5	0.5 ± 0.5	0.3 ± 0.4	16.0 ± 4.2
		Type 2	8.4 ± 0.6	0.4 ± 0.6	0.8 ± 0.4	0.6 ± 0.4	0.4 ± 0.5	16.2 ± 6.4

^aSignificantly different PRRSV-positive cells between spermatogonia and spermatocyte.
^bSignificantly different numbers of apoptosis between type 1 and type 2 PRRSV-infected boars.

ISSN: 1743-422X