1. At the end of the peak laying period for fowl, both performance and egg quality decrease markedly. Counteracting either or both of these could, therefore, have significant positive economic implications. Quercetin, a typical representative of the flavonol compounds, has a variety of biological functions. However, there are no reported findings on its use as a feed additive. 2. In this study, we investigated the effects of quercetin on laying rate, egg quality and blood traits associated with egg quality in laying hens (Hessain) during the late laying period and explored the possibility of using quercetin as a functional feed additive. 3. The laying hens (n = 240; 39 weeks old) were randomly assigned to 4 treatments consisting of 6 replicates (n = 10) and were fed with diets containing quercetin at 0, 0.2, 0.4 or 0.6 g/kg. 4. Results showed that laying rate was increased and feed-egg ratio was decreased significantly by 0.2 and 0.4 g/kg quercetin. Compared with controls, Haugh unit, eggshell strength, eggshell thickness and yolk protein were increased, but yolk cholesterol was decreased by quercetin. 5. In conclusion, quercetin was beneficial in improving performance and egg quality. The recommended concentration of quercetin is 0.4 g/kg of the basal diet. At this concentration, increased laying rate, improved egg quality and reduced yolk cholesterol can be expected.

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Wetting-drying cycles can influence decomposition of litter and soil organic carbon (SOC) and their mineralization, but such effects have seldom been explored in alpine wetland soils. We conducted a 120-day incubation experiment with alpine wetland soils to which we added litter or not. These soil samples were assigned to two constant moisture treatments (60% or 100% soil water-holding capacity, WHC) or to a wetting-drying treatment that cycled between 60% and 100% WHC. Drying-rewetting cycles significantly accelerated carbon (C) mineralization and nitrogen (N) immobilization compared to soil under saturated soil moisture conditions. Litter addition greatly increased C mineralization and N immobilization, but the intensity of mineralization was regulated by soil moisture through microbial biomass. A significantly negative relationship between C and N mineralization became more pronounced when litter was added. Thus, drying-rewetting cycles can alter C and N mineralization, and this effect can strongly depend on litter in alpine wetlands. This indicates that future climate change could affect C stocks in alpine wetland soil through altering moisture and litter production.

Rice straw is a byproduct of agricultural production and an important agricultural resource. However, rice straw has not yet been effectively used, and incorrect treatment methods (such as burning in the field) can cause serious damage to the environment. Studies have shown that straw returning is beneficial to soil, but there have been few studies focused on the effect of the amount of short-term straw returned on the soil microbial community. This study evaluates 0%, 50%, 75%, and 100% rice straw returned to the field on whether returning different amounts of straw in the short term would affect the diversity and composition of the soil microbial community and the correlation between bacteria and fungi. The results show that the amount of straw returned to the field is the main factor that triggers the changes in the abundance and composition of the microbial community in the paddy soil. A small amount of added straw (≤ 50% straw added) mainly affects the composition of the bacterial community, while a larger amount of added straw (> 50% straw added) mainly affects the composition of the fungal community. Returning a large amount of straw increases the microbial abundance related to carbon and iron cycles in the paddy soil, thus promoting the carbon and iron cycle processes to a certain extent. In addition, network analysis shows that returning a large amount of straw also increases the complexity of the microbial network, which may encourage more microbes to be niche-sharing and comprehensively improve the ecological environment of paddy soil. This study may provide some useful guidance for rice straw returning in northeast China.

Saline-sodic soil is one of the major threats to crop growth, production, and quality. Biochar amendment could alleviate the adverse impacts of saline-sodic stress in crops. However, the effect of biochar on root morphological, root physiological functions, and rice yield in saline-sodic paddy soil has not been studied. Here, the underlying mechanisms of positive effects in morphological characteristics and physiological functions of rice roots under heavily saline-sodic paddy soil amended with biochar were evaluated. The soil was amended with biochar at zero-biochar (CK), 15g kg-1 soil (T1), 30 g kg-1 soil (T2), or 45 g kg-1 soil (T3). Biochar addition significantly increased root length, root volume, root dry weight, and root-shoot ratio at all growth stages. The root absorption vigor and root oxidization capacity were enhanced and increased significantly by decreasing Na+/K+ ratio, MDA content, and increasing K+ concentration in rice root after biochar amendment. The root bleeding rate of biochar treatments at different growth stage were 11.01% to 67.73% greater than these of CK. The yield of rice was increased significantly under saline-sodic paddy soil after biochar amendment. It was concluded that biochar had positive effect on the morphological characteristics and physiological functions in rice roots in saline-sodic paddy soil.

Background Salmonella pullorum is one of the most harmful pathogens to avian species. Magnolol and honokiol, natural compounds extracted from Magnolia officinalis, exerts anti-inflammatory, anti-oxidant and antibacterial activities. This study was conducted to evaluate the effects of dietary supplemental magnolol and honokiol in broilers infected with S. pullorum. A total of 360 one-day-old broilers were selected and randomly divided into four groups with six replicates: the negative control group (CTL), S. pullorum-infected group (SP), and the S. pullorum-infected group supplemented with 300 mg/kg honokiol (SPH) or magnolol (SPM). Results The results showed that challenging with S. pullorum impaired growth performance in broilers, as indicated by the observed decreases in body weight (P < 0.05) and average daily gains (P < 0.05), along with increased spleen (P < 0.01) and bursa of Fabricus weights (P < 0.05), serum globulin contents, and the decreased intestine villus height and villus/crypt ratios (P < 0.05). Notably, supplemental magnolol and honokiol attenuated these adverse changes, and the effects of magnolol were better than those of honokiol. Therefore, we performed RNA-Seq in ileum tissues and 16S rRNA gene sequencing of ileum bacteria. Our analysis revealed that magnolol increased the α-diversity (observed species, Chao1, ACE, and PD whole tree) and β-diversity of the ileum bacteria (P < 0.05). In addition, magnolol supplementation increased the abundance of Lactobacillus (P < 0.01) and decreased unidentified Cyanobacteria (P < 0.05) both at d 14 and d 21. Further study confirmed that differentially expressed genes induced by magnolol and honokiol supplementation enriched in cytokine-cytokine receptor interactions, in the intestinal immune network for IgA production, and in the cell adhesion molecule pathways. Conclusions Supplemental magnolol and honokiol alleviated S. pullorum-induced impairments in growth performance, and the effect of magnolol was better than that of honokiol, which could be partially due to magnolol’s ability to improve the intestinal microbial and mucosal barrier.