Abstract
This study aimed at testing the hypothesis that greater inclusion of spray dried plasma (SDP) in diets improves growth performance, intestinal morphology, and reduces inflammation in weaned pigs. Four-hundred weaned pigs (body weight: 6.05 ± 0.80 kg) were allotted to a randomized complete block design with 5 diets and 2 blocks (16 pens/diet; 5 pigs/pen). Pens were not cleaned between groups to create a sanitation challenge. Phase-1 diets containing 0, 2, 4, 6, or 8% SDP were formulated. One pig per pen was sacrificed on d 14 and samples of intestinal tissue and mucosa were collected. Data were analyzed using PROC MIXED of SAS and linear, quadratic, and cubic contrast statements were used. During phase-1, ADG, ADFI, G:F, and body weight of pigs on d 14 increased (linear, P < 0.05) with increasing levels of SDP in the diet (Table 1). Villus width in the jejunum of pigs on d 14 tended to increase (linear, P < 0.10) with increasing inclusion of SDP (Table 2), and villus height:crypt depth tended to increase (quadratic, P < 0.10) with the greatest value observed for pigs fed a diet with 8% SDP. Secretory immunoglobulin A in the jejunal mucosa was decreased when 4 or 8% SDP was included in the diet (cubic, P < 0.05). Interleukin- (IL-) 2 (quadratic, P < 0.10) and IL-18 (cubic, P < 0.10) in the jejunal mucosa tended to decrease at 8% inclusion of SDP and IL-8 (linear, P < 0.10) tended to increase as SDP inclusion increased in the diet. In conclusion, the optimal inclusion of SDP in diets for weanling pigs was 8% as indicated by improvements in growth performance, but the collective intestinal morphology and health data do not result in a clearly conclusive optimum concentration in SDP.
