Submitted to: Applied Poultry Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 3, 1997
Publication Date: N/A
Interpretive Summary: Broiler hatching eggs in the US are not usually sanitized. Eggs that are deemed too dirty for use are not sent to the hatchery. We have shown that by sanitizing these "dirty" eggs they can be made suitable for use in the hatchery. Eggs with noticeable fecal contamination were washed and compared to those that were clean. It was found that sanitized "dirty" eggs have the same microbial loads as sanitized clean eggs. In both cases the sanitizing treatment lowered the total aerobic bacterial populations and Enterobacteriaceae (a group which includes E. coli and Salmonella) populations significantly. These sanitizing techniques will help control the spread of microorganisms from breeder farms to the hatchery.
Technical Abstract: Nest clean and floor/slat eggs were sampled monthly across the productive period of a commercial broiler breeder flock. Eggs were examined for total aerobic bacterial and Enterobacteriaceae counts per egg. Comparisons were made to paired eggs that had been spray sanitized in a two stage commercial egg washer. In the egg washer, the first stage was a chlorine detergent wash followed by a quarternary ammonia sanitizing spray. As the flock aged, numbers of bacteria per egg fluctuated without a noticeable trend (from Log(10) 4.1 to 5.3 aerobic bacteria). Bacterial populations were significantly lower on sanitized eggs (Log(10) 0.8 to 3.2 cells total aerobic bacteria and 2-5 cells Enterobacteriaceae per egg) regardless of hen age. Those eggs classified as floor/slat eggs had visible fecal contamination and higher bacterial numbers than nest clean eggs (Log(10) 5.9 to 7.6 cells total aerobic bacteria per egg). After sanitization, floor/slat eggs had bacterial populations that were not different from sanitized nest clean eggs. When examined at transfer, floor/slat eggs were still microbiologically indistinguishable from sanitized nest clean eggs, though both groups had higher numbers than observed in samples taken immediately following sanitization. Time of day eggs are collected was not found to have a significant effect on the microbiological profile of hatghing egg. On farm egg sanitizing effectively reduced the bacterial numbers recovered from nest clean and slat/floor eggs to the same level.