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)A 90.0 (9/10)B 0.001
Sows IP25.6AB 77.5ABC 26.8B 94.4C 0.00526.2A 86.0B 0.000
Pigs seropositive6.8 (4/59)A 74.6 (50/67)B 5.1 (3/59)C 90.0 (54/60)D 0.0005.9 (7/118)A 81.9 (104/127)B 0.000
Pigs IP15.6A 68.1B 29.0A 79.6B 0.00022.3A 73.2B 0.000
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)A 80.0 (8/10)B 0.023
Sows IP39.0AB 56.4AB 19.9A 68.8B 0.04930.5A 62.6B 0.017
Pigs seropositive42.2 (27/64)A 66.7 (38/57)B 3.3 (2/60)C 77.6 (45/58)B 0.00023.4 (29/124)A 72.2 (83/115)B 0.000
Pigs IP42.4A 79.3B 24.6C 65.2D 0.00038.5A 72.5B 0.000
  • 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).