Dietary Eucommia ulmoides Extract Alleviates the Effect of Cold Stress on Chick Growth Performance, Antioxidant and Immune Ability

This study aimed to investigate the protective value of Eucommia ulmoides extract (EUE) on chicks under cold stress. A total of 21 compounds were identified in EUE using mass spectrometry (LC-MS). Ninety chicks were divided into a control group (CS) fed a basal diet and an experimental group supplemented with EUE, exposed to 10 ± 1 °C for 8 h per day. Results showed, compared with the CS group, the body weights (BW) (p < 0.01) and average daily gains ADG (p < 0.05) of the EUE group were increased throughout the study period. Chicks fed EUE had higher AFI (0–7 d, p < 0.001) and lower feed-to-gain ratios (F/G) (0–15 d, p < 0.001). EUE increased the activities of superoxide dismutase (SOD) (15 d, p < 0.05) and glutathione peroxidase (GSH-Px) (7 d, p < 0.05), whereas it decreased malondialdehyde (MDA) (15 d, p < 0.01). The contents of IgA (7 d, p < 0.05), IgG (7 d; 15 d, p < 0.01), and IgM (15 d, p < 0. 001) were higher in the EUE group. Dietary EUE could also reduce chick organ damage. Overall, EUE as a natural feed additive can improve the growth performance, antioxidant capacity, and immune level, and reduce the organ damage of cold-stressed chicks.

Data-Driven Mathematical Modeling and Dynamical Analysis for SARS-CoV-2 Coinfection with Bacteria

The ongoing coronavirus disease-2019 (COVID-19) pandemic caused by severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) has serious influences on human health and economy. The available clinical data suggest that patients infected by SARS-CoV-2 have the possibility of simultaneous infection of bacteria. In this study, we present a data-driven mathematical model for coinfection of SARS-CoV-2 and bacteria to investigate the dynamics of COVID-19 progress. Specifically, based on the statistical analysis of different clinical data from China and some other countries, a system model with ordinary differential equations (ODEs) in four variables, i.e. SARS-CoV-2, bacteria, neutrophils and lymphocytes, is established. We further validate our model through theoretical analysis and fitting of different clinical data. Moreover, through numerical simulations and bifurcation analysis, we find that bacterial infection and immune-related parameters in certain ranges lead to the system transitions among three steady states, i.e. mild, severe and death. We also analyzed the influence of the time it takes for patients to switch from a high-risk area to a low-risk area on the recovery time. These results reveal that the coinfection of viruses and bacteria can explain the changes in neutrophils and lymphocytes, and that initial bacterial infection and immune-related parameters have great influences on the severity degree and mortality in COVID-19 patients. Together, our model and quantitative analysis suggest that preventing bacterial infection and enhancing immune ability during the early phase of infections could be a potential treatment option for high-risk COVID-19 patients.

The Dynamics of Neutralizing Antibody Level in One Year After SARS-CoV-2 Infection

Background: A lot of recent researches have focused on the duration of the nature immunity elicited by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. An improved understanding of the immunity offered by the antibodies developed against SARS-CoV-2 in recovered patients is critical for the development of diagnostic tests and vaccines. Methods: We enrolled 114 donors, which providing blood samples after discharge for half a year and one year. Neutralizing antibodies (NAbs) were tested using a micro-neutralization assay. Results: In two tests, 82 of 114 recovered patients completed the first test half a year after discharge and NAbs remained detectable in the vast majority of patients (75/82, 91.46%). In the comparison of the two intervals, 50% (27/54) of individuals had increased NAbs titers. when 31.48% (17/54) of patients remained unchanged. Conclusion: Our results suggest that immune ability is acquired in most individuals infected with SARS-CoV-2 and is sustained in a majority of patients for up to a year after recovery.

Effect of Antimicrobial Peptides on the Growth and Immunity of Swamp Eels

This study aimed to investigate the effect of different levels of antimicrobial peptides (AMPs) supplementation in the diet feed on growth performance, survival rate, biochemical parameters in swamp eels. Healthy fishes were randomly assigned to five groups feeding with different supplementation of AMPs (0, 200, 400, 600, or 800 mg/kg) in diets for 68 days. Results showed that relative weight gain, feed coefficient and survival rate were significantly (p<0.05) increased by supplementation of AMPs in feed. Level of protein (TP), triglyceride TG, alanine transaminase (ALT), alkaline phosphate (ALP), acid phosphate (ACP), superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) in the serum were significantly (p<0.05) improved in all AMPs treatments, while no significant difference was found between the control and AMPs 200 mg/kg. AMPs supplementation significantly enhanced (p<0.05) the survival rate and immune protection in swamp eels after challenged with Aeromonas hydrophila compared to the control group and eels fed with AMPs 800 mg/kg had the highest survival rate and immune protection (32.50 and 85.71%, respectively). The diets containing AMPs enhanced the survival rate, immune ability, and antioxidant capacity in swamp eels, indicate that an appropriate dosage of AMPs can be used as a potential alternative to antibiotics in swamp eels.

PtP38 May Increase the Immune Ability of Portunus trituberculatus Stimulated by LPS Imitating a Gram-Negative Bacterial Infection

The P38 mitogen-activated protein kinase (MAPK) signal transduction pathway is widespread in organisms and plays important roles in immune activities. The infection mechanism of environmental gram-negative bacteria on crustaceans is an important scientific problem. In this study, the cDNA full-length sequence of Portunus trituberculatus P38 (PtP38) was cloned and its structure was analyzed by bioinformatics methods. To study the function of the PtP38 gene after a Gram-negative bacterial infection, we injected P. trituberculatus with LPS to activate the immune response instead of directly infecting with Gram-negative bacteria. With LPS stimulation, the expression of the PtP38 gene in different tissues increased significantly. At the same time, the expression of immune-related genes (ALF and crustin) in the hepatopancreas, activities of antioxidant enzymes [superoxide dismutase (SOD), catalase (CAT), and inducible nitric oxide synthase (iNOS) enzymes], and expression of apoptosis-related genes (caspase2 and caspase3) were increased significantly. To further conform the function of PtP38 in the immune response, we injected P. trituberculatus with P38 inhibitor and subsequently injected with LPS. The results showed that the expression of immune-related genes was inhibited, the activity of antioxidant enzymes was decreased, and the expression of apoptosis-related genes were inhibited. Thus, we speculated that PtP38 may increase the immune ability by improving the expression of antimicrobial peptides, increasing the activity of oxidative stress-related enzymes, and promoting cell apoptosis in infected P. trituberculatus. This study also laid the foundation for further study of the P38 MAPK signaling pathway and immune mechanism of P. trituberculatus.

Effects of dietary levan-type fructan on growth performance, blood profiles, fecal noxious gas emissions, and litter performance in lactating sows

In total, 28 multiparous sows (n = 7) and their litters were used to determine the effects of levan-type fructan supplementation on growth performance, nutrient digestibility, blood profiles, and fecal noxious gas emissions. The dietary treatments included (1) CON, basal diet; (2) FC1, CON + 0.1% fructan; (3) FC2, CON + 0.2% fructan; and (4) FC3, CON + 0.3% fructan. No significant differences were observed (P > 0.05) in body weight (BW), average daily feed intake, or back fat loss in lactating sows among treatments. However, blood lymphocyte concentrates were higher (P < 0.05) in sows fed levan-containing diets than in those fed the CON diet. Weaning BW and overall average daily gain (ADG) of piglets in the FC3 treatment were higher (P < 0.05) than piglets in the CON treatment. Blood lymphocytes and nutrient digestibility of sows, as well as the weaning BW and the ADG of piglets were increased linearly (P < 0.05) as the concentration of levan increased in the diet. The diarrhea score of piglets and the fecal gas emissions of sows decreased linearly (P < 0.05) as dietary levan increased. In conclusion, levan supplementation did not affect feed intake or decrease back fat loss of lactating sows, but it improved nutrient digestibility and immune ability, decreased fecal noxious gas emissions of lactating sows, and it improved growth performance and reduced diarrhea in piglets.

Red light corrects neonicotinoid induced immunodeficiency and impaired respiration in poisoned bumblebees

Neonicotinoid pesticides undermine mitochondrial function in insects including bumblebees, reducing ATP, mobility and leading to death. They also reduce bumblebee immunocompetency leaving them vulnerable to pathogen attack. This undermines key pollinators critical in the agricultural economy. However, 670nm light exposure improves mitochondrial function undermined by age or disease, increasing respiratory chain efficiency, improving ATP production, mobility and survival in bumblebees and fruit flies. Here we show that 670nm restores immunocompetence, improving hemocyte counts and hemolymph anti-microbial action. Additionally, we measure whole body respiration in vivo in individual bumblebees revealing that it is a functional metric of both neonicotinoid impact and light induced mitochondrial protection. Critically we show that only 1 min 670nm exposure is sufficient to correct respiratory deficits induced by pesticide and restore normal immune ability. Longer exposures are not more effective. Further, single 1 min exposure protects respiration and immunity for approximately 3-6 days. Hence, 670nm impact is not dose dependent but switch like.These data provide a compelling rational for 670nm application to protect pollinators on which a major part of the agro economy is based and who are being challenged by aggressive pesticide application.

Understanding the Capability of an Ecosystem Nature-Restoration in Coal Mined Area

Ecosystem issues have been severely concerned and studied when the coal resource is one of major energy generators, and green mining innovation techniques involving artificial-restorations have addressed and significantly lessened negative impacts on the ecological environment. The ecosystem of a coal-mined area, however, is able to naturally restore with the processes of natural succession, similar to the human body system that has the immune ability to self-heal a wound over time if the wound does not deeply hurt the health. Here we analyze multiple discipline real data from two mining sites, and evidently show an ability of nature that the coal mining related problems such as geological cracks, damaged aquifers and destroyed soils in Quaternary period can naturally recover around a half-year after the end of mining. Our results temporally and spatially demonstrate that the damaged ecosystem has a capability of unaided nature-remediation from the ground to the subsurface, which is very useful to the countries worldwide with abundant coal reserves and intense energy demands for their development.