A two-year follow-up study of the PCV2 status of a Danish pig herd that was initially assumed to be PCV2-free

Table 1 Average amount of PCV2 virus in pooled blood samples from pigs during a two-year period (log10 PCV2 copies/mL)

	10 pigs weighing 45 kg		10 pigs before slaughter
	PCV2 vaccinated	PCV2 virus load (no. positive/no. tested)	PCV2 vaccinated	PCV2 virus load (no. positive/no. tested)
2010
January	Yes	neg^*	Yes	neg
March	No	neg	Yes	neg
May	Yes	10^4**	No	10^7**
June	Yes	neg	Yes	neg
August	Yes	neg	Yes	neg
October	Yes	neg	Yes	neg
November	Yes	neg	Yes	neg
2011
Janaury	Yes	neg	Yes	neg
February	Yes	neg	Yes	neg
April	Yes	neg	Yes	neg
May	Yes	neg	Yes	10⁶ (1/10)
July	Yes	neg	Yes	neg
September	No	10⁵ (1/10)	Yes	neg
November	Yes	neg	No	10⁶(10/10)
December	Yes	neg	Yes	10⁵ (3/10)
2012
January	Yes	neg	Yes	10⁵ (2/10)

*Negative: the amount of PCV2 was below the detection limit (<3 log10 copies/mL).
**Samples from 2010 were not investigated individually.

ISSN: 2055-5660