IMMUNE-RESPONSE OF SOWS AND THEIR OFFSPRING TO PSEUDORABIES VIRUS - SERUM NEUTRALIZATION RESPONSE TO VACCINATION AND FIELD VIRUS CHALLENGE

  • 1 January 1984
    • journal article
    • research article
    • Vol. 48  (2) , 184-191
Abstract
One month prior to breeding, sows were vaccinated with an attenuated psuedorabies virus vacine or challenged with a field strain of pseudorabies virus. A 3rd group of sows were not vaccinated or challenged before breeding. Pigs from these sows were vaccinated at 3, 6 or 12 wk of age and challenged with virulent virus 3 wk later. One pig from each litter served as an unvaccinated, unchallenged control. Serum neutralization titers of these pigs were monitored from birth until 22 wk of age. Titers of the sows were monitored through breeding, gestation and farrowing. The maximum prefarrowing antipseudorabies virus titer in the field virus challenged sows occurred 4 wk following challenge. A significant decline in titers occurred at farrowing. Titers rose froim 1 wk postfarrowing and then declined. Titers in the field virus infected sows were consistently 2- to 3-fold greater than those of the vaccinated sows. The maximum prefarrowing antipseudorabies virus titer in the vaccinated sows occurred 6 wk following vaccination. The geometric mean titer in these sow''s then decreased and increased for 2 wk after farrowing. The results in the pigs can be summarized as follows. Pigs from control sows had a greater serological response following field virus challenge than following vaccination with a modified live virus. Pigs from control sows responded serologically to vaccination at 3, 6 and 12 wk of age. Pigs from control sows which were challenged at 6, 9 and 15 wk of age had similar antibody responses. Pigs from vaccinated sows had no increase in titer following vaccination at 3 and 6 wk of age. Titers increased when these pigs were vaccinated at 12 wk of age. There was no significant increase in mean titers of pigs from challenged sows following vaccination at 3, 6 and 12 wk of age. Vaccinated pigs from control and vaccinated sows had a secondary response following challenge 3 wk after vaccination. Vaccinated pigs from challenged sows did not have a secondary response when challenged at 6 and 9 wk of age. These pigs did have a secondary response when challenged at 15 wk of age.