Effect of Organic Selenium Supplementation on the Antioxidant Status, Immune Response, and the Relative Expression of IL-2 and IFN-γ Genes in Ewes During the Hot Season

Impact of 5-20% Hydroponic Wheat Sprouts Inclusion on Growth and Metabolic Parameters of Growing Ewes

The aim of this study was to assess the impact of varying proportions (5-20%) of hydroponic wheat sprouts in the diet of growing four-month-old Hu ewes on their productive performance, metabolic profiles, rumen fermentation, and alterations in microflora. Compared with the control group (CON), the optimum final weight of ewes has been presented in the group of substitution 15% (S15) of the basal diet with hydroponic wheat sprouts. Furthermore, 1-30 d the average daily gain (ADG), 31-60 d ADG, and average feed intake were both significantly improved in S15 compared with CON (p < 0.05). Feeding hydroponic wheat sprouts can significantly increase high-density lipoprotein and interleukin-2 (p < 0.05) accompanied by the numerical increase of the content of interferon-γ, suggesting its positive effect on ewes' health and immune systems. In this process, it is noteworthy that feeding hydroponic wheat sprouts results in an increase in relative abundance of Olsenella, Limosilactobacillus, Shuttleworthia, and Prevotella_7, and a decrease in relative abundance of Succinimonas, Pseudobutyrivibrio, and Anaerovibrio in the rumen of growing ewes. It implies that the response of rumen microflora adapted to the change of dietary ingredients, as well as the relationship between rumen microflora changes and the improvement of productive performance and immune system in growing ewes. Considering the usage cost and application effect, S15 of the basal diet with hydroponic wheat sprouts could be the appropriate application solution for growing ewes.

Egg Yolk Selenopeptides: Preparation, Characterization, and Immunomodulatory Activity

In this study, egg yolk selenium peptides (Se-EYP) were prepared using double-enzyme hydrolysis combined with a shearing pretreatment. The properties of the selenopeptides formed were then characterized, including their yield, composition, molecular weight distribution, antioxidant activity, in vitro digestion, and immunomodulatory activity. The peptide yield obtained after enzymatic hydrolysis using a combination of alkaline protease and neutral protease was 74.5%, of which 82.6% had a molecular weight <1000 Da. The selenium content of the lyophilized solid product was 4.01 μg/g. Chromatography-mass spectrometry analysis showed that 88.6% of selenium in Se-EYP was in the organic form, of which SeMet accounted for 60.3%, SeCys2 for 21.8%, and MeSeCys for 17.9%. After being exposed to in vitro simulated digestion, Se-EYP still had 65.1% of oligopeptides present, and the in vitro antioxidant activity was enhanced. Moreover, Se-EYP exhibited superior immune detection indices, including immune organ index, level of immune factors in the serum, histopathological changes in the spleen, and selenium content in the liver. Our results suggest that Se-EYP may be used as selenium-enriched ingredients in functional food products.

Abnormal Phenylalanine Metabolism of Procapra przewalskii in Chronic Selenosis in Selenium-Enriched Habitats

Selenium (Se)-enriched habitats have led to chronic selenosis, seriously affecting the health and survival of Procapra przewalskii (P. przewalskii). Our targets were to explore the molecular mechanisms of chronic selenosis and to look for a new way to protect endangered species. The mineral contents of soils, grass, blood, and muscle were analyzed. The biochemical indices, antioxidant capability, and immune function were also investigated. The analyses of proteomics and metabolomics were also carried out. The results showed that the Se contents in the muscle and blood of P. przewalskii, and the soil and grass in the Se-enriched habitats were significantly higher than those in healthy pastures. The P. przewalskii in the Se-enriched habitats showed symptoms of anemia, decreased antioxidant capability, and low immune function. A total of 44 differential proteins and 36 differential metabolites were screened by analyzing their proteomics and metabolomics. These differential proteins and metabolites were involved in glycolysis pathway, amino acid biosynthesis, carbon metabolism, phenylalanine metabolism, and energy metabolism. In particular, phenylalanine metabolism was the common pathway of proteomics and metabolomics, which was an important finding in studying the mechanism of chronic selenosis in animals. This study will help us to further understand the mechanism of chronic selenosis in P. przewalskii, and it provides a scientific basis for the protection of endangered species in Se-enriched habitats.