In Taiwan, wide application of LPC vaccine resulted the high immunity in the sows. The offsprings therefore got the high titer of colostal antibody and the jttency of Lit vaccination in these piglet was often interfered. In trting to avoid the interference of colcxostral antibody by using the gcxd LPC vaccine, piglet were vaccinated with a mixture of LPC and BVD antigens for this test.
The pjglet aged 3 weeks in Tapu were vathnated with LPC + BVD (NY1 strain), Lit +BVD @11GM stain) and LPC + BVD (Fp&s strain) resjtotively and did&t
show any led reaction after vaccination. Seven weeks poGtvaccnaton, the vaccinatl pigs were select! and sent to the laboratory for ALD challenge. They showed no or slight reaction and all survived. Most piglet possessed the colostral antibody titer of 1.21 or above liefcrxe vaccination. After vaccination the antibody titer increased or decreased derend on the original level of oolc€tral antibody titer. After challenge, the gcduction of antibcdy was rapid and most pigs reached the tiler over 2.68.
Before challenge, BVD antibody was low but increased to 2.21 two weeks postchallenge