Table 5

Percentage and number (in parentheses) of seropositive sows and pigs at 12–24 hours post-farrowing and at weaning, respectively, together with the inhibition percentages (IP)

Herd A
abcdP valuea– c (NV)b–d (V)P* value
Sows seropositive20.0 (1/5)80.0 (4/5)0.0 (0/5)100.0 (5/5)0.38010.0 (1/10)A90.0 (9/10)B0.001
Sows IP25.6AB77.5ABC26.8B94.4C0.00526.2A86.0B0.000
Pigs seropositive6.8 (4/59)A74.6 (50/67)B5.1 (3/59)C90.0 (54/60)D0.0005.9 (7/118)A81.9 (104/127)B0.000
Pigs IP15.6A68.1B29.0A79.6B0.00022.3A73.2B0.000
Herd B
abcdP valuea– c (NV)b–d (V)P* value
Sows seropositive40.0 (2/5)80.0 (4/5)0.0 (0/4)80.0 (4/5)0.53222.0 (2/9)A80.0 (8/10)B0.023
Sows IP39.0AB56.4AB19.9A68.8B0.04930.5A62.6B0.017
Pigs seropositive42.2 (27/64)A66.7 (38/57)B3.3 (2/60)C77.6 (45/58)B0.00023.4 (29/124)A72.2 (83/115)B0.000
Pigs IP42.4A79.3B24.6C65.2D0.00038.5A72.5B0.000
  • Vaccination status: NV (non-vaccinated sow batches and their pigs) and V (vaccinated sow batches and their pigs). The P value refers to the comparisons between the individual farrowing batches, and the P* value to the comparisons between the summaries of the NV (a–c) and V (b–d) batches. Values with different superscripts within a row are significantly different (P<0.05 and P*<0.05).