Assessment of immediate production impact following attenuated PRRS type 2 virus vaccination in swine breeding herds

Table 1 Statistical process control (SPC) analysis of the data on the individual farm level

Production parameter	Frequency of signals^a	Duration of signals	Magnitude of signals
Abortion rate	4/65 (6.1%)	1 to 7 weeks	0.11 to 0.16%
Neonatal losses	5/65 (7.7%)	1 to 5 weeks	0.34 to 1.85
Pre-weaning mortality	2/65 (3.1%)	1 to 5 weeks	3.99 to 5.21%
Total pigs weaned	0/65 (0.0%)	N/A	N/A
Wean-to-first-service interval	2/65 (3.1%)	3 to 5 weeks	1.03 to 1.44 days

^a = A decrease in productivity following each MLV intervention, with performance parameters crossing the EWMA control limits, was defined as a signal

ISSN: 2055-5660