Alternative Feed Additive, Associated or Not with Antibiotic, in Weaned Piglets Feeding: Growth Performance and Diets Digestibility

This study evaluated an alternative feed additive associated or not with colistin, in a 2 x 2 factorial arrangement, in weaned piglets feeding on ADG, ADFI, feed conversion ratio (FCR), and apparent total tract digestibility (ATTD) of DM, OM, CP and GE. One hundred and eight crossbred piglets (5.3 ± 0.5 kg) were used in a three-phase feeding program (21-35, 36-50, 51-65 days of age), and fed the following diets: a control diet (CON), with no inclusion of growth promoter feed additive; a diet with 40 ppm of colistin (diet COL); a diet with 0.3% of alternative additive (benzoic acid and the essential oils of eugenol, thymus and piperine - diet AA); and a diet with 0.3% of alternative additive and 40 ppm of colistin (diet AACOL). The diets were composed by corn, soybean meal, dairy products, and spray-dried blood plasma, supplemented with minerals, vitamins, and amino acids, and formulated to provide 3.40, 3.38, and 3.20 Mcal of ME/kg; 220, 215, and 190 g/kg of CP; and 14.5, 13.3, and 10.9 g/kg of digestible lysine, in phases 1, 2, and 3, respectively. A randomized block design based on initial BW was used. The data was submitted to ANOVA by the GLM procedure of SAS (9.4), and means were separated using Tukey test (5%). Alternative feed additive inclusion in the diets increased (P < 0.05) ADG (91.8 g vs. 114.3 g) and ADFI (163.3 g vs. 190.1 g) of piglets in phase 1, compared to pigs fed diets without the product. The alternative additive improved (P < 0.05) ATTD of CP in phase 1 (68.6% vs. 71.0%), ATTD of GE in phases 1 (75.2% vs. 77.4%), and 3 (77.1% vs. 79.0%), and ATTD of DM in phase 3 (77.1% vs. 79.1%). The antibiotic inclusion in the diets increased (P < 0.05) ATTD of CP in phase 1 (68.2% vs. 71.5%). The alternative feed additive and colistin interacted (P < 0.05) for ATTD of DM in phases 1 and 2, and ATTD of OM, CP, and GE in phase 2. The ATTD of DM in phases 1 and 2, and the ATTD of OM, CP, and GE in phase 2 of diets AA and COL were greater (P<0.05) than of diet CON, but similar (P>0.05) to diet AACOL. The alternative feed additive was effective in improving growth performance and diets digestibility in piglets soon after weaning.