Surveillance of Classical Swine Fever Virus Antibody Titers in Sows and their Piglets under Different Vaccination Programs

Abstract

Classical swine fever virus (CSFV), serum neutralizing antibody titers of 854 sows were determined using a neutralizing peroxidase linked assay (NPLA). Blood samples were collected one-week post-partum from 1st- 6th parity sows, from 30 swine fever-free farms. The farms were divided according to their vaccination programs, 10 farms for
each program. Program A sows had been vaccinated 3 weeks pre-partum (288 samples). Program B sows had been vaccinated 3 weeks post-partum (276 samples). Program C sows had been vaccinated 3 times/year (290 samples). The means log2 CSFV antibody titer of the sows in programs A, B, C were 6.591.88, 5.722.04 and 6.612.04 respectively.
Serum samples from 1 week old (1,924 samples) and 3 week old piglets (1,809 samples) born to the sows using the vaccination programs (A, B, C), from the 15 farms were collected and their CSFV maternal derived antibody titres were determined. The mean log2 of the maternal derived, antibody titers in the piglets was seen to decrease with a half-life of approximately two weeks. The correlation between serum neutralizing antibody titers in the sows and their piglets was demonstrated by r2 = 0.22. Our results showed that all the three vaccination programs provided the protective levels of antibody. Furthermore, it suggests that the profiles of the CSFV specific, neutralizing antibody titers in the sows can be used as a guideline for planning a classical swine fever vaccination program for their piglets.