Bacteria isolated from free-range chicken (Gallus gallus domesticus) eggs sold in semiarid conditions and its one health impact

ABSTRACT

Background: Food contamination is an important and growing public health concern due to the risk of foodborne illnesses.In this context, the egg, consumed all over the world, stands out. This food has been pointed out as a carrier of severalbacteria, causing outbreaks of food toxinfection. The production of free-range chicken (Gallus gallus domesticus) eggs hasbeen an alternative for generating income for producers in Brazil; however, there is no monitoring of the sanitary qualityof this product. The objective of this study was to identify microorganisms in 128 free-range chicken eggs sold in openmarkets in the semiarid region of Northeastern Brazil.Materials, Methods & Results: The study was carried out at commercial fairs in the state of Rio Grande do Norte, Braziliansemiarid region. The minimum number of eggs to be used was determined by the formula for simple random samples considering the following parameters expected frequency of positive eggs of 50% (for sample maximization), 95% confidencelevel and sampling error of 10%. The minimum number of eggs to be sampled was 97; however, 128 eggs were obtained inthe period from August 2018 to April 2019. The internal content of the eggs was subjected to bacteriological culture usingan adapted methodology, and for the in vitro susceptibility assessment the disk diffusion method on Müller-Hintonagarwasused. In addition to biochemical tests, Gram-negative bacteria were subjected to microbiological diagnosis using theMALDI-TOF (Matrix Associated Laser Desorption-Ionization - Time of Flight) technique. Bacterial growth was found in40 (31.3%) eggs. The microorganisms most frequently isolated were Staphylococcus spp. (27.5%), Bacillus spp. (15%) andEnterobacter cloacae (25%). There was bacterial growth in albumens [n = 10; 7.8%] and in egg yolks [n=38; 29.7%] (P< 0.001). The antimicrobials that showed highest resistance rates were ampicillin...(AU)