The effects of egg yolk on nursery pig growth performance

Abstract Text: An experiment was conducted to determine the effects of egg yolk compared to spray-dried plasma on growth performance and circulating immunoglobulins in nursery pigs.  Crossbred pigs (n = 72) were weaned at 24 d (7 ± 0.54 kg) and divided into 3 dietary treatments in a completely randomized design (CRD), resulting in 6 pens per treatment with 4 pigs per pen (2 barrows, 2 gilts).  The 3 dietary treatments were standard nursery diets supplemented with spray-dried plasma (2.36%), egg yolk (6%), and a control, which were fed in 2 phases (Phase 1: d 0 to 7; Phase 2: d 7 to 21). In the third phase (Phase 3: d 21 to 28), all pigs were fed the same diet.  Pigs and feeders were weighed and blood samples were collected on d 0, 7, 14, 21, and 28.  Growth performance (ADG, ADFI, G:F) was analyzed using PROC GLIMMIX of SAS.  Circulating immunoglobulins (IgA and IgG) were analyzed using repeated measures by time.  For Phase I and II, growth performance was not affected by dietary treatment.  The overall means for growth performance parameters were: Phase I (ADG = 90.2 g, ADFI = 149.5 g, G:F = 553.7 g/kg); Phase II (ADG = 436.7 g, ADFI = 644.6 g, G:F = 677.9 g/kg).  During Phase III, ADG was affected by treatment (P < 0.10).  Pigs consuming the egg yolk diet had greater (P < 0.05) ADG vs. the plasma group (647.5 g vs. 538.7 g; respectively) for Phase III.  Circulating immunoglobulins were not affected by dietary treatment.  The concentration of IgA increased from d 0 (0.17 ng/mL) to 28 (0.3 ng/mL; time; P < 0.0001).  The concentration of IgG did not respond (P > 0.10) over the course of the 28-d trial.   These results indicate that performance and circulating immunoglobulins are similar in pigs receiving nursery diets containing egg yolk or spray dried plasma. 

Keywords: egg yolk, growth performance, nursery pigs