RESUMEN
Feed fiber composition is usually considered as one of the factors that have an impact on digestive tract microbiota composition. The investigations on the level of fermentation and in-vitro digestibility of different fibers are not well understood. The aim of the current study is to determine the effect of different fiber sources on intestinal nutrient digestibility, hindgut fermentation, and microbial community composition under in vitro conditions using pigs' hindgut as a model. The experimental treatment diets contained alfalfa hay, cornstalk, and rice straw. Cornstalk treatment displayed higher digestibility compared to alfalfa hay and rice straw; similar results were observed with in-vitro digestibility using intestinal digesta. Firmicutes were the most abundant phyla (Firmicutes = 89.2%), and Lactobacillus were the prominent genera (75.2%) in response to alfalfa compared to rice straw and cornstalk treatments. In simulated in-vitro digestion, corn stalk fiber improved dry matter digestibility; rice straw fiber improved volatile fatty acid content and fermentation efficiency. Alfalfa fiber improved the thickness of deposited Firmicutes and Lactobacillus.
RESUMEN
There are some disparities between pharmacological and toxicological xenobiotic receptor (xenosensors) pathways. These variations include receptor models that indicate several toxic patterns. Such models have demanded some update from traditional medical receptor relations studied by pharmacologists. These may include the response time, the molecular level, and unclear directions of toxicological metabolism. Xenosensors activities were affected by many factors that include genetic elements, physiological status, xenobiotic complication, and species-specific variations. Thus, this review aims to highlight the most advanced features of xenosensors related to toxicant biotransformations and other patterns such as characteristics, recognition, and the relations between different xenosensors.
