Case Report of Handling PDNS in Fattening Pigs by PCV2 Vaccination in Breeder and Piglet

Porcine Dermatitis and Nephropathy Syndrome (PDNS) is a clinical sign of Porcine Circovirus Associated Disease (PCVAD). PDNS is characterized by purple skin lesions with black center, fever, and lethargy, mostly affecting fattening pigs between 12-16 wks old. Vaccination is one of the tools to handle PCV2 and PDNS. This case report illustrates the real situation in pig farm in Thailand that suffered from PDNS for years and how the farm changed vaccination program in breeders and piglets and how serology and morbidity improved from 2014 to 2015.

A farrow to finisher farm with 1,200 sows, one-site and continuous flow in each unit was observed. There were gilt acclimatization, boar (AI), gestation, lactation, nursery (3-11 wks old), and fattening (12-24 wks old-600 pigs/house) units. During 2014 to Jun 2015, PCV2 was positive by serology (ELISA), serum PCR (viremia at 12-16 wks old) and tissue PCR of sick pigs. The clinical signs of PDNS occurred from nursery (8-9 wks old). Incidence was increased from 10% in nursery to 40-50% in fattening at 12-16 wks old with viremia found in this group in Dec 2014. Mortality was lower than 20% but times to market were increased. From 2014 to Jun 2015, subunit PCV-2 vaccine was applied to sow at 10-12 wks of gestation, piglets at 3 and 7 wks old, gilts at 20 wks old. No PCV2 vaccine used in boars. From Jun 2015 to Nov 2015, new PCV2 vaccine type and program was applied. The inactivated PCV2 vaccine was used 2ml in gestating sows at 8 wks of gestation, gilt at 20 wks old, and boar at every six months. Piglets were vaccinated at 5 wks old, 0.5 ml. During transition period, 9-14 wks gestating sows were vaccinated with 2 ml vaccine and 8-11 wks old pigs were vaccinated with 0.5 ml vaccine. Serum of breeders and fattening were collected and tested by ELISA (Biochek) in Dec 2014 and Aug 2015, before and after new vaccine program. PDNS morbidity rate in fattening was observed in Nov 2015.

Mean S/P ratio of PCV2 in breeder were 1.797, 1.801, 1.710, 1.671 in gilts, Sow P1, P2-5, and P> 5 in Dec 2014.Three months after new PCV2 vaccination, mean S/P ratio were increased to 2.072, 2.474, 2.316, and 2.256, respectively, in Aug 2015. In nursery to fattening, mean S/P ratio were 1.669, 1.361, 0.604, 0.895 in 7-8 wks old, 10-12 wks old, 14-16 wks old, and 18-20 wks old in Dec 2015 and 2.260, 1.550, 1.072, and 1.060, respectively, in Aug 2015. No PCV2 seroconversion was detected in Aug 2015. PDNS morbidity in Nov 2015 was 3/600 (0.5%) at 14-16 wks old.

The inactivated PCV2 vaccine in boar and earlier vaccination program in gestating sows (8 wks of gestation) can improve PCV2 immunity in breeders, piglets, and fattening pigs and reduce PDNS in fattening pigs according to the practical use in PDNS high incident farm.

Disclosure of Interest: None Declared.