Lysolecithins are added to poultry diets to promote the intestinal absorption of nutrients, in particular of dietary fats. Lysolecithins contain a mixture of phospho- and lysophospholipids and differ in composition depending on the conditions and source of the lecithin used for its production. The importance of the lysolecithin composition and its interaction with the fat type was investigated in vitro in a fat digestion model and in vivo in a digestibility trial with broilers (24 to 28 d age). The in vitro digestion of soybean oil and pig lard was investigated without and with the inclusion of soybean or rapeseed lysolecithin. Correspondingly, for the digestibility trial, 108 Ross 308 male broilers were assigned to 6 dietary treatments: a basal diet with either soybean oil (5.3%) or pig lard (5.8%), each basal diet supplemented with 250 ppm soybean lysolecithin, and each basal diet supplemented with 250 ppm rapeseed lysolecithin. In vitro pig lard digestibility was significantly lower compared to soybean oil digestibility. Although in vivo no significant difference was observed for crude fat digestibility, broilers fed the basal diet with pig lard had a lower (P < 0.05) DM digestibility, nitrogen retention, and AMEn compared to those fed the basal diet with soybean oil. Lysolecithin supplementation showed a significant interaction with the fat type, both in vitro and in vivo. The in vitro hydrolysis of pig lard, but not of soybean oil, increased (P < 0.001) with supplementation of soybean and rapeseed lysolecithin. Moreover, soybean and rapeseed lysolecithin supplementation improved (P < 0.05) DM digestibility of the basal diet with pig lard by 5.1 and 5.7%, respectively; nitrogen retention by 2.8 and 3.1 g/kg, respectively; and AMEn by 182 and 199 kcal/kg, respectively. Despite the major difference in molecular composition, there was, however, no impact of the lysolecithin composition on in vitro and in vivo fat digestibility. This study demonstrates that the improvements that can be made with lysolecithin supplementation are highly dependent on the fat incorporated in broiler feeds.

Egg washing is currently not permitted within the European Union, with few exceptions. This is mainly because there are concerns that cuticle damage could occur during or after the washing process, as a result of a suboptimal operation. In this study, the cuticle coverage levels of 400 washed or unwashed eggs, derived from either a brown or a white egg-laying flock at the end of lay, were compared. The eggs from older hens inherently have poorer cuticle coverage and as a result arguably constitute a greater risk to consumer safety if they are then washed. Thus, the effects of the washing procedure used in this study on cuticle quality were tested under the worst-case scenario. A standard Swedish egg washing process was used. The cuticle coverage of the eggs was assessed by a colorimeter by quantifying the color difference before and after staining with Tartrazine and Green S. The cuticle of an additional 30 eggs from each of the four groups was then visually assessed by scanning electron microscopy. The staining characteristics of the cuticle varied greatly within each group of eggs and showed that the washing process did not lead to cuticle damage. Scanning electron microscopy confirmed that there was no irreversible damage to the cuticle of the washed eggs and that it was not possible to correctly assign the treatment (washed or not) based on a visual assessment. In conclusion, no evidence could be found to suggest that the washing procedure used in this investigation irreversibly changed the quality of the cuticle.

Zinc is an essential nutritional trace element for all forms of life as it plays an important role in numerous biological processes. In poultry, zinc is provided by in-feed supplementation, mainly as zinc oxide or zinc sulfate. Alternatively zinc can be supplemented as organic sources, which are characterized by using an organic ligand that may be an amino acid, peptide, or protein to bind zinc and have a higher bioavailability than inorganic zinc sources. There are limited number of studies directly comparing the effects of inorganic vs. organic zinc sources on performance and intestinal health in broilers. Therefore, a digestibility and a performance study were conducted to evaluate and compare the effect of an amino acid-complexed zinc source vs. an inorganic zinc source on intestinal health. The experiment consisted of 2 treatments: either a zinc amino acid complex or zinc sulfate was added to a wheat–rye based diet at 60 ppm Zn, with 10 replicates (34 broilers per pen) per treatment. Effects on performance, intestinal morphology, microbiota composition, and oxidative stress were measured. Supplementing zinc amino acid complexes improved the zinc digestibility coefficient as compared to supplementation with zinc sulfate. Broilers supplemented with zinc amino acid complexes had a significantly lower feed conversion ratio in the starter phase compared to birds supplemented with zinc sulfate . A significantly higher villus length was observed in broilers supplemented with zinc amino acid complexes at days 10 and 28. Supplementation with zinc amino acid complexes resulted in a decreased abundance of several genera belonging to the phylum of Proteobacteria. Plasma malondialdehyde levels and glutathione peroxidase activity showed an improved oxidative status in broilers supplemented with zinc amino acid complexes. In conclusion, zinc supplied in feed as amino acid complex is more readily absorbed, potentially conferring a protective effect on villus epithelial cells in the starter phase.

Campylobacter jejuni is one of the leading causes of food-borne gastroenteritis. Because of the high prevalence of C. jejuni in poultry, poultry meat is considered a major source of C. jejuni infections for humans. However, it is not known whether all poultry-associated C. jejuni strains are capable of causing disease in humans. Four different virulence properties of C. jejuni strains were compared between 20 poultry isolates and 24 human isolates. Strains were chosen based on their PFGE pattern to represent a heterogeneous population. The isolates were compared for their ability to invade and induce interleukin-8 (IL-8) production in T84 cells, their production of functional cytolethal distending toxin (CDT) using HEp-2 cells, and their sodium deoxycholate resistance. All four virulence factors were present among strains of human and poultry origin, with strong differences observed among strains. For invasion and IL-8 induction, no difference was observed between the two populations. However, on average, human isolates arrested more HEp-2 cells in their cell cycle than did the poultry isolates (P=0.041), suggesting higher CDT production by the former. The ability to survive 16 000 mu g sodium deoxycholate ml(-1) was significantly more pronounced (P=0.006) among human isolates than poultry isolates, although all strains possessed the cmeABC operon. These data suggest that all four virulence properties are widespread among C. jejuni isolates, but that a higher degree of bile-salt resistance and more pronounced CDT production are associated with strains causing enteritis in humans

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