Effects of protein and/or energy restriction for six weeks on antioxidation capacity of plasma and gastrointestinal epithelial tissues of weaned kids

Tannic acid reduced apparent protein digestibility and induced oxidative stress and inflammatory response without altering growth performance and ruminal microbiota diversity of Xiangdong black goats

The present study was performed to evaluate the impacts of tannic acid (TA) supplementation at different levels on the growth performance, physiological, oxidative and immunological metrics, and ruminal microflora of Xiangdong black goats. Twenty-four goats were randomly assigned to four dietary treatments: the control (CON, basal diet), the low-dose TA group [TAL, 0.3 % of dry matter (DM)], the mid-dose TA group (TAM, 0.6 % of DM), and the high-dose TA group (TAH, 0.9 % of DM). Results showed that the growth performance was unaffected (P > 0.05) by adding TA, whilst the 0.3 % and 0.6 % TA supplementation significantly decreased (P < 0.05) the apparent digestibility of crude protein (CP) and ruminal NH3-N concentration, and raised (P < 0.05) the level of total volatile fatty acid (TVFA) in rumen. The increments of alanine aminotransferase (ALT), triglyceride (TG), cortisol (CORT), total antioxidant capacity (T-AOC), interleukin (IL)-1β, IL-6, and serumamyloid A (SAA), and decrements of globulin (GLB), immunoglobulin G (IgG), cholinesterase (CHE), glutathione reductase (GR), creatinine (CRE), growth hormone (GH), high-density lipoprotein cholesterol (HDLC), and insulin-like growth factor 1 (IGF-1) to different extents by TA addition were observed. Although the Alpha and Beta diversity of rumen bacterial community remained unchanged by supplementing TA, the relative abundance of the predominant genus Prevotella_1 was significantly enriched (P < 0.05) in TAL. It could hence be concluded that the TA supplementation in the present trial generally decreased CP digestion and caused oxidative stress and inflammatory response without influencing growth performance and ruminal microbiota diversity. More research is needed to explore the premium dosage and mechanisms of effects for TA addition in the diet of goats.

Effects of Selenylation Modification on Antioxidative Activities of Schisandra chinensis Polysaccharide

The selenylation modification of Schisandra chinensis polysaccharide (SCP) was conducted by the HNO₃–Na₂SeO₃ method respectively under nine conditions according to L₉(3⁴) orthogonal design. Nine selenizing SCPs, sSCP₁–sSCP₉, were obtained, and their antioxidant activities were compared. In vitro test, the free radical-scavenging rates of nine sSCPs were determined for DPPH., .OH and ABTS⁺. sSCP₁ presented the most significant effect, and could inhibit the nonenzymatic protein glycation. In vivo test, 14-day-old chickens were injected respectively with sSCP₁ and SCP, the serum contents of CAT, SOD and MDA were determined. The result showed that as compared with the SCP group, the SOD and CAT activities were significantly or numerically raised and MDA content was significantly or numerically lowered in the sSCP₁ group. These results indicate that selenylation modification can significantly enhance the antioxidant and antiglycative activity of SCP in vitro or in vivo. sSCP₁ possesses the best efficacy and its modification conditions can be as optimal modification conditions that were 200 mg of Na₂SeO₃ for 500 mg of SCP, reaction temperature of 50°C and reaction time of 6 h.