Recovery of probiotic bacteria from the intestinal tract of broilers after noninvasive pre-hatch application

This paper reports the success of intestinal colonisation of chickens and foetuses by probiotics after different methods of pre-hatch application. Hatcheries not using in ovo injection of probiotics or wish to avoid the reduced hatchability associated with in ovo injections prefer using alternatives to in ovo technologies. Therefore, we used noninvasive pre-hatch application methods. This included the vertical transmission of probiotics from the mother hen to offspring, application of probiotic late in incubation and transmission of probiotics during hatch. Enterococcus faecium (NCIMB11181) and Lactobacillus animalis (DSM33570) were used as probiotics. Probiotics were applied either through drinking water for the mother hens, by dipping the eggs in a probiotic solution on days 16-18 of incubation or through drops/spray on the eggshell of the fertilised eggs. Similarly, intestinal colonisation of the probiotic in chickens was investigated either before hatch (pre-hatch) or immediately after hatch (post-hatch). Based on the performed experiments, it is concluded that E. faecium was vertically transmitted from the mother hen to the offspring, as E. faecium was recovered in 20 and 33% of the offspring pre- and post-hatch, respectively. When applied on the eggshell, the recovery of E. faecium before hatch depended on the application method and ranged from 0 to 9%. In contrast, L. animalis was not recovered before hatch. Moreover, when sampling post-hatch 100% of the chickens were colonised when E. faecium was used and 54% were colonised when L. animalis was used. Furthermore, spray application with E. faecium was the most successful application method as 9% of the foetuses were colonised pre-hatch and 100% became colonised post-hatch. Therefore, pre-hatch application by, for example, spray of probiotics on the eggshell can be used as an easy-to-use, noninvasive method for early life colonisation of chicken gut.