A STANDARDIZED OLIVE POMACE EXTRACT MAINTAINED SIMILAR PIGLET GROWTH PERFORMANCE TO HIGH LEVELS OF ZnO

The impending EU ban on using high ZnO levels (3,000 ppm) in weanling pig diets has accelerated the search for alternative solutions aiming to prevent post-weaning diarrhea while maintaining piglet performance in the nursery period. A standardized olive pomace extract (PE1, recommended dose: 0.25%), with anti-inflammatory properties, and a rosemary extract (PE2, recommended dose: 0.06%), with antioxidant and anti-inflammatory properties, were evaluated as alternatives. The aim of this study was to evaluate the PE1 and PE2 plant extracts and their optimal dose in a dietary strategy without high ZnO levels. The study, conducted at ILVO (Melle, Belgium) consisted of 480 piglets allotted to one of eightdietary treatments at 12 pens per treatment (5 piglets/pen) from weaning (21 d of age) to 35 days
after weaning. Dietary treatments were fed during the first 2 weeks followed by a common diet
given for another 3 weeks. Dietary treatments were as follows: (1) negative control (150 ppm ZnO;
NC), (2) positive control (3,000 ppm ZnO; PC), (3) PE1 at 0.15% (PE1-0.15), (4) PE1 at 0.20%
(PE1-0.20), (5) PE1 at 0.25% (PE1-0.25), (6) PE2 at 0.020% (PE2-0.02), (7) PE2 at 0.040% (PE2-
0.04), and (8) PE2 included at 0.060% (PE2-0.06). Data on body weight (BW), BW gain (DG),
feed intake (FI), and gain to feed ratio (G:F) were collected and analyzed by a mixed model with
treatment, phase, and their interaction as fixed effects Piglets fed high ZnO showed significantly improved growth performance and G:F relative to the
negative control, followed by piglets fed with standardized olive pomace extract at 0.25% (PE1-
0.25) which also showed numerically higher performance to the negative control in weeks 5-8
(carry-over effect).