Effect of a synbiotic supplement on cecal microbial ecology, antioxidant status, and immune response of broiler chickens reared under heat stress

The aim of this study was to examine the effect of a dietary synbiotic supplement on the cecal microflora, antioxidant status, and immune response of broiler chickens under heat stress (HS). A total of 360 one-day-old male Ross 708 broiler chicks were randomly distributed among 3 dietary treatments containing a synbiotic (PoultryStar consists of Bifidobacterium animalis, Enterococcus faecium, Lactobacillus reuteri, Pediococcus acidilactici, and fructooligosaccharides) at 0 (control), 0.5 (0.5X), and 1.0 (1.0X) g/kg. Each treatment contained 8 replicates of 15 birds each housed in floor pens. Heat stimulation was at 32°C for 9 h daily from day 15 to 42. Heat stress-induced changes of cecal bacteria were detected using bacteria-specific agars, and spleen protein concentration and mRNA expression of interleukins and antioxidants were examined using ELISA and real-time PCR, respectively. Under the HS condition, synbiotic fed broilers regardless of dose had lower cecal enumerations of Escherichia coli and coliforms, and a lower heterophil/lymphocyte (H/L) ratio (P < 0.05) compared to controls. 1.0X group also had higher cecal enumerations of Bifidobacterium spp. and Lactobacillus spp., spleen glutathione peroxidase (GPx), and plasma nuclear factor erythroid 2-related factor 2 (Nrf-2), and a lower H/L ratio compared to both control and 0.5X groups (P < 0.05). However, there were no treatment effects on the levels of Enterococcus spp., the circulating monocytes, eosinophils, and basophils, Toll like receptor-4 (TLR-4), interleukin-6 (IL-6), interlukin-10 (IL-10), and their mRNA expression, as well as plasma Kelch-like ECH-associated protein 1 (Keap-1) (P > 0.05). These results suggest that the synbiotic could inhibit the negative effects of HS on broiler health through the reduction of cecal pathogens, regulation of stress reactions, and improvement of antioxidant status.

Efficacy and immunogenicity of a live L. acidophilus expressing SAD epitope of transmissible gastroenteritis virus as an oral vaccine

Transmissible gastroenteritis virus (TGEV) causes great economic loss to swine industry worldwide. Vaccination is an important method to control the TGEV infection. In this study, a TGEV oral vaccine was generated by transferring a eukaryotic expression recombinant plasmid carrying the SAD (A and D antigenic sites of the S protein) epitope of TGEV into a swine-origin Lactobacillus acidophilus (L. acidophilus). In orally immunized BALB/c mice, the TGEV L. acidophilus oral vaccine induced significantly higher level of SIgA antibodies specific to TGEV compared with the mice immunized with a commercial inactivated TGEV vaccine and similar levels of IgG specific to TGEV as the inactivated vaccine. Furthermore, the TGEV L. acidophilus oral vaccine induced higher levels of IFN-γ, which suggested that the vaccine was able to induce immune response. In brief, this novel TGEV L. acidophilus oral vaccine could induce high levels of both mucosal and humoral immune responses, which has a potential to be used in the pig industries in the future. Keywords: transmissible gastroenteritis virus (TGEV); live L. acidophilus oral vaccine; SIgA antibody; IgG antibody; IFN-γ; IL-4.

High-throughput screening method for evaluating spatial repellency and vapour toxicity to mosquitoes

Spatial repellents are an essential tool for personal protection against mosquitoes that bite and transmit disease pathogens to humans. Current repellent screening methods, such as olfactometers and alternative choice tests, are complex systems that require a relatively large quantity of compound (mg). The present study validates a high-throughput spatial repellent screening method using a glass tube that has the ends covered with netting, in addition to treated filters and plastic end caps. The apparatus occupies relatively little space, is easy to decontaminate, and requires small amounts of compound (μg). In a horizontal tube orientation, DEET (N,N-diethyl-meta-toluamide), citronella oil and IR3535 had 1 h half repellent concentration (EC₅₀ ) values of 32, 32 and 298 μg/cm² , respectively, against the Orlando strain of Aedes aegypti (L.) (Diptera: Culicidae). Vertical tube orientation increased EC₅₀ values by approximately two-fold, except IR3535, which remained essentially unchanged. Transfluthrin showed concentration-dependent spatial repellency (1 h EC₅₀  = 0.5 μg/cm² ) without any knockdown, although only in vertical tubes. Transfluthrin showed 50% knockdown in 1 h at 0.5 μg/cm² and 50% mortality at 0.15 μg/cm² in horizontal tubes. In conclusion, this high-throughput screening method is useful for assessing vapour toxicity and the spatial repellency of candidate molecules prior to semi-field and field studies.

Optimization of Dietary Zinc Requirement for Broiler Breeder Hens of Chinese Yellow-Feathered Chicken

Simple Summary

China is the second-largest global producer of chicken meat, almost half of which is from the Chinese yellow-feathered breed; a systematic program has been initiated to improve its feeding standards. This study evaluated the optimal requirement of dietary zinc for maximal egg production, egg quality, tibial quality, and antioxidant indices of laying broiler breeders. The results revealed several beneficial effects of supplementary zinc on egg production, feed conversion ratio, yolk zinc content, tibial quality and the antioxidant indices in the serum, liver and ovary. The optimal zinc requirement was estimated based on a regression model.

Abstract

This study aimed to establish the optimal dietary zinc requirement of Chinese yellow-feathered Lingnan broiler breeders. A total of 576 breeder hens aged 58 weeks were randomly assigned to six treatments, each with 6 replicates of 16 birds (n = 96/treatment). The hens were fed either a basal diet (22.81 mg/kg Zn) or the same basal diet supplemented with additional 24, 48, 72, 96, and 120 mg Zn/kg up to 65 weeks of age. Compared to the results of birds fed the basal diet (22.81 mg Zn/kg), the dietary supplementation with additional Zn (mg/kg) showed higher egg laying rate (at 48–120 mg), EM (at 96 mg/kg), yolk Zn content (at 24–120 mg/kg), fertility (at 48–120 mg/kg), hatchability (at 48–96 mg/kg), tibial breaking strength (at 24–48 mg/kg), tibial ash content (at 48 mg/kg), serum CuZnSOD activity (at 72 mg/kg) and T-AOC (at 48 mg/kg), and ovarian CuZnSOD and GSH-Px activities (at 96–120 mg/kg), and lower FCR (at 96 mg/kg). The regression model showed that the optimal supplemental Zn for maximal egg laying rate, yolk Zn content, fertility, and hatchability of Chinese yellow-feathered broiler breeders aged 58 to 65 weeks were 71.09, 92.34, 94.44 and 98.65 mg/kg diet, respectively.

Impacts of Graded Levels of Metabolizable Energy on Growth Performance and Carcass Characteristics of Slow-Growing Yellow-Feathered Male Chickens

A dose-response study was conducted to investigate the metabolizable energy (ME) requirement for Lingnan chickens from 9 to 15 weeks of age. One thousand two hundred 8-week-old slow-growing yellow-feathered male chickens were allotted to five dietary ME levels (2805, 2897, 2997, 3095 and 3236 kcal/kg). The results revealed that the daily metabolizable energy intake increased (p < 0.01), whereas the feed intake and feed:gain ratio decreased linearly (p < 0.01) with the increment in dietary ME level. The final body weight and daily gain of the highest ME treatment tended (p > 0.05) to be greater than those obtained with the lower ME levels. The fat content in breast muscle showed a quadratic response (p < 0.05) to the increase in dietary energy level. The shear force values of breast muscle in the 2897, 3095 and 3236 kcal/kg treatments were lower (p < 0.05) than those of the 2997 kcal/kg treatment. In conclusion, among the tested ME levels, 3095 kcal/kg was adequate for feed intake, shear force, and plasma uric acid, and 3236 kcal/kg tended to increase the body weight, body gain, and feed conversion ratio of Lingnan males between 9 and 15 weeks of age; further studies are still required for testing higher levels.

Relationship between serum homocysteine and different menopausal stage

Objective: This study aimed to investigate the serum level of homocysteine in menopausal women and to explore the association between menopausal status, blood lipids, and homocysteine concentrations.Methods: The study recruited females aged 40-60 years who were not receiving menopausal hormone therapy. The demographic characteristics and menopausal status of the women were collected in the form of questionnaires. The study analyzed the association between hyperhomocysteinemia and variables using binary logistic stepwise regression.Results: Among 366 enrolled subjects, menopausal status was divided into four stages: premenopause stage (n = 135), menopausal transition stage (n = 91), early postmenopause stage (n = 87), and late postmenopause stage (n = 53). The proportion of hyperhomocysteinemia in the premenopausal stage, menopausal transition stage, and postmenopausal stage was 43%, 26.4%, and 45%, respectively (χ² = 8.999, p = 0.011). The mean concentration of homocysteine was 9.75 µmol/l. The level of homocysteine was higher in the postmenopause stage than in the other stages (p = 0.043), and the difference between postmenopause and menopausal transition was statistically significant (p < 0.01). In the binary logic analysis, menopausal transition compared with postmenopause (odds ratio = 2.027, 95% confidence interval = 1.117-3.679, p = 0.005).Conclusions: Serum homocysteine levels are associated with menopausal status. Homocysteine concentrations were progressively higher across menopausal stages. The transformation in the female body across the menopause transition stages may cause elevations in the homocysteine level in postmenopausal women.

TNF-derived peptides inhibit tumour growth and metastasis through cytolytic effects on tumour lymphatics

Tumour necrosis factor (TNF) is a multi-functional cytokine with profound and diverse effects on physiology and pathology. Identifying the molecular determinants underlying the functions and pathogenic effects of TNF is key to understanding its mechanisms of action and identifying new therapeutic opportunities based on this important molecule. Previously, we showed that some evolutionarily conserved peptides derived from TNF could induce cell death (e.g. apoptosis and/or necrosis), a feature of immune defence mechanisms shared by many vertebrates. In this study, we demonstrated that necrosis-inducing peptide P16 kills human glioblastoma cancer cells and primary human hepatoma or renal cancer cells isolated from patients who had not responded to standard treatments. Importantly, we show that the necrosis-inducing peptide P1516 significantly improves survival by inhibiting tumour metastasis in a 4T1 breast cancer syngeneic graft mouse model. Because the lymphatic system is an important metastatic route in many cancers, we also tested the effect of TNF-derived peptides on monolayers of primary human lymphatic endothelial cells (hDLEC) and found that they increased junctional permeability by inducing cytoskeletal reorganization, gap junction formation and cell death. Transmission electron microscopy imaging evidence, structural analysis and in-vitro liposome leakage experiments strongly suggest that this killing is due to the cytolytic nature of these peptides. P1516 provides another example of a pro-cytotoxic TNF peptide that probably functions as a cryptic necrotic factor released by TNF degradation. Its ability to inhibit tumour metastasis and improve survival may form the basis of a novel approach to cancer therapy.

A novel therapy, using Ghrelin with pegylated G-CSF, inhibits brain hemorrhage from ionizing radiation or combined radiation injury

Medical treatment becomes challenging when complicated injuries arise from secondary reactive metabolic and inflammatory products induced by initial acute ionizing radiation injury (RI) or when combined with subsequent trauma insult(s) (CI). With such detrimental effects on many organs, CI exacerbates the severity of primary injuries and decreases survival. Previously, in a novel study, we reported that ghrelin therapy significantly improved survival after CI. This study aimed to investigate whether brain hemorrhage induced by RI and CI could be inhibited by ghrelin therapy with pegylated G-CSF (i.e., Neulasta®, an FDA-approved drug). B6D2F1 female mice were exposed to 9.5 Gy 60Co-γ-radiation followed by 15% total-skin surface wound. Several endpoints were measured at several days. Brain hemorrhage and platelet depletion were observed in RI and CI mice. Brain hemorrhage severity was significantly higher in CI mice than in RI mice. Ghrelin therapy with pegylated G-CSF reduced the severity in brains of both RI and CI mice. RI and CI did not alter PARP and NF-κB but did significantly reduce PGC-1α and ghrelin receptors; the therapy, however, was able to partially recover ghrelin receptors. RI and CI significantly increased IL-6, KC, Eotaxin, G-CSF, MIP-2, MCP-1, MIP-1α, but significantly decreased IL-2, IL-9, IL-10, MIG, IFN-γ, and PDGF-bb; the therapy inhibited these changes. RI and CI significantly reduced platelet numbers, cellular ATP levels, NRF1/2, and AKT phosphorylation. The therapy significantly mitigated these CI-induced changes and reduced p53-mdm2 mediated caspase-3 activation. Our data are the first to support the view that Ghrelin therapy with pegylated G-CSF is potentially a novel therapy for treating brain hemorrhage after RI and CI.

Activation of the cannabinoid receptor 2 increases renal perfusion

Acute kidney injury (AKI) is an increasing clinical problem that is associated with chronic kidney disease progression. Cannabinoid receptor 2 (CB2) activation has been shown to mitigate some of the deleterious tubular effects due to AKI, but its role on the renal vasculature has not been fully described. In this study, we investigated the effects of our novel CB2 receptor agonist, SMM-295, on renal vasculature by assessing cortical perfusion with laser Doppler flowmetry and changes in luminal diameter with isolated afferent arterioles. In this study, intravenously infused SMM-295 (6 mg/kg) significantly increased cortical renal perfusion (13.8 ± 0.6%; P < 0.0001; n = 7) compared with vehicle (0.1 ± 1.5%; n = 10) normalized to baseline values in anesthetized C57BL/6J mice. This effect was not dependent upon activation of the CB1 receptor (met-anandamide; 6 mg/kg iv) and was predominantly abolished in Cnr2 knockout mice with SMM-295 (6 mg/kg iv). Ablation of the renal afferent nerves with capsaicin blocked the SMM-295-dependent increase in renal cortical perfusion, and the increased renal blood flow was not dependent upon products synthesized by cyclooxygenase or nitric oxide synthase. The increased renal perfusion by CB2 receptor activation is also attributed to a direct vascular effect, since SMM-295 (5 μM) engendered a significant 37 ± 7% increase ( P < 0.0001; n = 4) in luminal diameters of norepinephrine-preconstricted afferent arterioles. These data provide new insight into the potential benefit of SMM-295 by activating vascular and nonvascular CB2 receptors to promote renal vasodilation, and provide a new therapeutic target to treat renal injuries that impact renal blood flow dynamics.

Designing a minimally-invasive, ultrasound-guided, percutaneous flexor tendon sheath lavage technique: a cadaver study

The goal of this study was to develop a minimally-invasive, ultrasound-guided percutaneous flexor tendon sheath lavage technique on cadaver model. Two catheters were inserted using ultrasound guidance at the proximal and distal ends of the tendon sheath in 20 fingers from cadaveric forearms. Percutaneous injection of a saline solution colored with methylene blue resulted in anterograde lavage of the flexor tendon sheath. The technique was successful in 13 out of 20 cases. The proximal catheter was in the correct position in 17 cases and the distal catheter was correctly positioned in 15 cases. The flexor tendons were continuous in all cases and had puncture wounds in 9 cases. Based on our study, this minimally-invasive, ultrasound-guided percutaneous lavage of the flexor tendon sheath was effective in 65% of cases and safe in 100% of cases in the index, middle and ring fingers. If this percutaneous lavage fails, it is always possible to switch to a conventional open technique.