Anti-ovalbumin (OVA) IgG in pigs fed diets containing fish meal (FM), spray-dried plasma (SDP), bioprocessed soybean meal, or their combination. The control (CON) diets contained FM and SDP. Pigs were intramuscularly injected with 0.5 mg Quil A (Brenntag Biosector A/S, Frederikssund, Denmark), 0.5 mg OVA (Sigma-Aldrich, St. Louis, MO), and 0.5 mg killed Candida albicans in 1 mL of saline at d 7 and 21, representing the prime and booster doses. Serum was collected at 7, 21, and 28 d for determination of presensitization, primary, and secondary anti-OVA IgG. Data represents least squares means and SEM of 10 pigs/dietary treatment at d 7 and 21, and 5 pigs/dietary treatments at d 28. BPSBM+SDP = the CON with bioprocessed soybean meal replacing FM; BPSBM+FM = the CON with bioprocessed soybean meal replacing SDP; BPSBM[ = the CON with bioprocessed soybean meal replacing both FM and SDP.