Resumen en inglés

Probiotics and prebiotics are currently postulated as a potential replacement alternative to antibiotics used in subtherapeutic doses, as growth promoters. Among its advantages we find that they do not leave residues in the meat of the bird, they improve the integrity and stability of the intestinal flora and therefore the productive performance of the bird. The research evaluated in 300 Cobb 500 broiler chickens (female and male 1 day old), the effect of a biopreparation based on the probiotic Lactobacillus Sallivarus, a prebiotic and an antibiotic, on the productive indices of chickens, The inclusion of the three treatments was carried out from day 1 of life until day 42 as an additive in drinking water, minimum populations of 10 8 CFU / ml of lactobacillus were guaranteed, for the analysis of the data Ia was used Duncan's (1955) comparison test, with a level of significance with α = 0.05 Tukey's test was used to make multiple comparisons between means. In the experiment, some productive indicators were evaluated, among them, live weight, feed consumption, weight gain and feed conversion that were controlled at 7, 14, 21,28, 35 and 42 days, The results found in each of the treatments detected significant differences at 7, 28 and 42 days in feed conversion, with a significant decrease in this indicator in the chickens that were treated with the biopreparations based on Lactobacillus sallivarius, in relation to the other treatments. These data suggest that these biopreparations have a positive effect on the productive indices of broilers and can be used as an alternative to decrease the use of antibiotics as growth promoters