|Carroll, Jeffery - Jeff Carroll|
Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: 7/21/2002
Publication Date: N/A
Technical Abstract: A trial using 64 weanling pigs (TR4 x PIC C22) was conducted to determine the effects of menhaden fish oil supplementation and diet complexity on performance and immune response of nursery pigs. Pigs (17 d and 6.27±1.16 kg) were weaned into a SEW facility and given free access to a complex diet for 7 d postweaning. At d 0 (d 7 postweaning), pigs were blocked by weight and allotted to 64 pens. Treatments (Trt) were arranged as a 2×2×2 factorial arrangement. Main effects included diet (complex vs simple), oil (menhaden fish [MFO] vs corn [CO]), and immunogen (saline vs lipopolysaccharide [LPS]). Experimental diets contained 6% oil (6% CO or 5% MFO + 1% CO) and were fed for 14 d. On d 12, i.v. injections of either LPS (100 µg/kg) or saline were given, followed by blood collection at 30 min intervals for 6 hr. After the immune challenge (d 14), pigs were placed onto a common corn-soybean meal fortified diet and growth performance was evaluated until termination of the study (d 28). Pigs were weighed and feed intakes recorded at 7, 14, and 28 d. Prior to immune challenge (d 12), there were differences in BW for pigs fed complex vs. simple diets (P < 0.01; 13.1 and 12.1 kg, respectively) and pigs fed CO vs. MFO diets (P < 0.05; 12.9 and 12.3 kg, respectively.) During the challenge period, for pigs treated with LPS there was a Time × Immunogen × Oil effect (P < 0.04) for serum cortisol with MFO fed pigs having lower serum cortisol as compared to CO fed pigs. Peak serum cortisol for LPS-treated pigs was 174.1 ng/ml at 3 hr post-challenge for MFO fed pigs and 234.2 ng/ml at 4 hr for CO fed pigs. At d 14 and 28, there were no differences (P > 0.05) in BW, except for pigs challenged with LPS. This study suggests, that by d 7 postweaning, pigs can be placed on a simplified diet without affecting performance and that menhaden fish oil supplementation may provide immunological protection.