Seleção de cepas de Bacillus subitilis para uso como probiótico em embriões

Abstract

Embryonic weight and embryo quality are factors that can interfere with one-day-old chickens’ performance and can be influenced by the inoculation of probiotics at the embryo stage. The present study aimed to evaluate the effects of inoculating different strains of Bacillus subtilis(BS) inside the air chamber of eggs descending from commercial broiler chickens over embryo weight during incubation time and embryo mortality rates. A total of 103 fertile eggs at 10-day-old of incubation were used. These eggs were sorted into different groups: one negative control group, one control group of a BS strain used in the market and seven treatment groups, each one of those were inoculated with a different BS strain. All embryos were inoculated with the same amount of bacteria through the air chamber. The embryos were weighed to obtain total and relative weight at 17 days old, right before being put through euthanasia. The embryos’ deaths were evaluated in a daily through ovoscopy and at 17 days old of incubation in order to calculate the embryonic death ratio. Among the studied strains, only two presented underperforming mortality rates compared to the control group, and strain G showed a 0% mortality rate. All strains presented the same embryo weight ratios, except for strain G, which resulted in heavier embryos. The end of this research concludes that strain G presents excellent potential to be used as a probiotic for poultry embryos, requiring further studies to prove such applicability. This work also shows that the use of embryos can be an alternative for the selection of probiotic strains for use iin ovarn animals.