pectins and Salmonella-Infections--Animal

Salmonella enteritidis (SE) is a major foodborne pathogen that causes human infections largely by consumption of contaminated eggs. The external surface of eggs becomes contaminated with SE from multiple sources, highlighting the need for effective egg surface disinfection methods. This study investigated the efficacy of three GRAS-status, phytochemicals, namely carvacrol (CR), eugenol (EG), and β-resorcylic acid (BR) applied as pectin or gum arabic based coating for reducing SE on shell eggs. White-shelled eggs, spot inoculated with a 5-strain mixture of nalidixic acid (NA) resistant SE (8.0 log CFU/mL) were coated with pectin or gum arabic solution containing each phytochemical (0.0, 0.25, 0.5, or 0.75%), and stored at 4°C for 7 days. SE on eggs was enumerated on days 0, 1, 3, and 7 of storage. Approximately 4.0 log CFU/egg of SE was recovered from inoculated and pectin or gum arabic coated eggs on day 0. All coating treatments containing CR and EG, and BR at 0.75% reduced SE to undetectable levels on day 3 (P < 0.05). Results suggest that the aforementioned phytochemicals could effectively be used as a coating to reduce SE on shell eggs, but detailed studies on the sensory and quality attributes of coated eggs need to be conducted before recommending their use.

Topics: Animals; Anti-Bacterial Agents; Chickens; Cymenes; Egg Shell; Eugenol; Gum Arabic; Hydroxybenzoates; Microbial Viability; Monoterpenes; Pectins; Phytochemicals; Poultry Diseases; Salmonella enteritidis; Salmonella Infections, Animal

1. Three experiments were performed to relate morphological characteristics of the small intestinal mucosal surface to age, dietary factors, small intenstinal microflora and performance of broilers. Characterisation of the small intestinal mucosal surface using a dissecting microscope was based on the orientation of the villi, villus shape and the presence of convoluted villi. 2. In Trial 1, the morphological changes of the mucosal surface were studied weekly in the period from 7 to 28 d of age. At d 7 mainly tongue- and leaf-shaped villi together with some ridge-shaped ones were observed in the middle section of the small intestine, displaying a regular zigzag pattern on 53% of the mucosal surface. During the period from d 7 to 14, the area with ridge-shaped villi increased from 7 to 63% and did not change significantly over the next 2 weeks. 3. In Trial 2, three protein sources, soy isolate (SI), wheat gluten (WG), hydrolysed wheat gluten (HWG) and SI with added L-glutamine (SI + Gln), were studied with respect to their effect as dietary components on villus morphology in the mid-small intestine and performance. Diets were fed with (0 to 14 d) and without pectin (14 to 21 d). Feed conversion ratio on the HWG diet improved in comparison to the native WG diet. During the period 0 to 14 d of age the mucosal area with zigzag-oriented villi increased when the pectin diet was supplemented with Gln. Moreover, weight gain of birds fed the SI + Gln diet increased in the period 41 to 21 d. 4. In Trial 3, a study was made of the morphological response of the villi to a stimulation of microbial activity in the digesta after addition of highly methylated pectin to the soybean meal (SBM) diet. This was performed with and without inoculation of a non-virulent Salmonella typhimurium on d 7. By d 21 the birds fed the pectin diet showed impaired weight gain and higher feed conversion. The pectin affected the mucosal surface by decreasing the area with the zigzag pattern and increasing the area with convoluted, mainly ridge-shaped villi. The Salmonella typhimurium infection increased the effects of pectin on performance and mucosal morphology.

Topics: Animal Feed; Animals; Body Weight; Chickens; Glutens; Glycine max; Intestinal Mucosa; Intestine, Small; Male; Pectins; Poultry Diseases; Salmonella Infections, Animal; Salmonella typhimurium