Enterocytes function as both absorptive and protective components of intestine that come in close contact with a variety of enteric factors, such as dietary, microbial, and parasites, that have potential to affect the organismal health. Understanding how enterocytes interact with this complex array of factors may help improve gut health particularly in the context of poultry production where it is also linked to food safety issues. The enterocyte in vitro culture can help screen different factors and their interactions with microbiome, and potentially be utilized in the development of interventions strategies for pathogens such as antibiotic alternatives. We developed a method to culture primary chicken enterocytes and conducted their characterization using cytochemical and proteomic methods, and investigated their potential to respond to different chemical stimuli. Using selected micronutrients, microbial toxins, and metabolic modulators, we assessed their effects on the viability and morphological changes in enterocytes. We found that whereas some nutritional factors (calcitriol, retinoic acid) produced different morphological changes, toxins such as aflatoxin B1 and deoxynivalenol produced enterocyte degeneration and death, and the bacterial lipopolysaccharide had very little effect compared on the basis of their mass. Both cyclic AMP and phorbol myristate acetate exhibited some cachectic effects on enterocytes with the later showing more severe changes. Thyroxin induced distinct morphological changes making the cells more cuboidal and Na-butyrate produced no significant change in morphology. The cytochemical and proteomic characterization suggest that these enterocytes largely belong to epithelial cell categories which may be amenable to analysis of biochemical paths and mechanisms of action of different factors that affect these cells. Based on these results we conclude that chicken enterocyte culture can be a useful in vitro model to study intestinal physiology.

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A commercial yeast culture feed supplement (YC; Celmanax SCP, Vi-COR, Mason City, IA) was provided to turkeys throughout a 16-wk grow-out to determine if it would prevent the effects of stress on production and pathogen colonization. The YC was provided either continuously at 100 g/t (YC-CS) or intermittently during times of stress at 200 g/t (YC-IS). Birds were stressed with an environmental challenge of Escherichia coli and by transporting them in a vehicle for 3 h after which they were penned in new social groups, without feed or water, for an additional 9 h. Turkeys were transported and challenged at 6, 12, and 16 wk of age to model the movement of birds within a 3-stage housing system. The YC-IS was provided only for the first week after hatch and for a 1-wk period encompassing each challenge. At wk 7 and 9, a decrease in BW of challenged birds was prevented by YC-IS but not YC-CS. There were no significant differences in BW due to either challenge or YC during wk 11 and 13. At wk 16, the challenge decreased BW, but there was no improvement in either of the YC treatments. Overall feed conversion ratio (FCR) was increased by transport/E. coli (P < 0.0001). The YC-CS improved FCR of challenged birds by 21 points, whereas YC-IS improved FCR by 36 points and this effect was significant (P = 0.013). The YC-CS tended to decrease both Salmonella and Campylobacter isolation from the ceca of stressed birds (P > 0.05). The YC-IS also tended to decrease Salmonella isolation (P > 0.05) with no effect on Campylobacter isolation. These data suggest that the practice of transporting turkeys decreases performance and that YC-IS may be more effective than YC-CS for alleviating the effects of this stressor on feed efficiency.