ABSTRACT The present study evaluated a probiotic and a competitive exclusion product injected in ovo on day 18 of incubation together with Marek's disease vaccine in eggs of 56-week-old broiler breeders. Three experiments were carried out. The first trial evaluated the effect of treatments on hatchability, cecal colonization of Salmonella Heidelberg (SH), and intestinal mucosa immunity (immunoglobulin A levels in the intestinal fluid). The second trial evaluated the viability of the microorganisms in the products inoculated in a solution containing diluent and Marek's disease vaccine. The third trial evaluated the colonization of the cecal microbiota in non-challenged chickens during first four days of life by culturing cecal samples under aerobic and anaerobic conditions. Hatchability was not affected by the treatments. SH cecal counts were reduced in three-day-old broilers inoculated in ovo with the competitive exclusion product. Liver and spleen pool SH counts were not different among treatments. Broilers inoculated in ovo presented higher intestinal IgA titers 24 hours after SH challenge compared with the controls. When birds were not challenged, lower cecal microbial counts in aerobic culture were determined in the control group than in the probiotic group on day 3, and in the competitive exclusion group on day 2 when cultured in anaerobiosis. The products inoculated and diluted in the vaccine solution were viable at all analyzed periods when cultured in anaerobiosis. The results of this study suggest in-ovo inoculation is an effective route for the administration of the evaluated products, which effectively enhanced the broilers' immune response to a SH challenge, as shown by the increase in IgA titers, and the reduction in cecal Salmonella Heidelberg colonization with the in-ovo inoculation with the competitive exclusion product.

O propósito deste trabalho é apresentar um operador genético desenvolvido a partir dos métodos matemáticos de extrapolação de curva. Este operador irá auxiliar na produção de um indivíduo melhor adaptado na população do algoritmo genético com codificação real, reconhecendo padrões inerentes aos genes dos cromossomos dos melhores indivíduos de cada geração. O operador proposto em conjunto com o algoritmo genético de codificação real é comparado com cinco outros métodos diferentes de otimização aplicados a prospecção geoelétrica.

This work presents a genetic operator developed from a mathematical curve extrapolation method. This operator help the production of fitter individual within a realcoded genetic algorithm in which inherent patters of the best individuals of each generations are recognized. The operator is compared to five alternative optimization techniques applied to geoelectrical prospection.