The Mobility of Eurasian Avian-like M2 Is Determined by Residue E79 Which Is Essential for Pathogenicity of 2009 Pandemic H1N1 Influenza Virus in Mice.

In 2009, a novel H1N1 influenza virus caused the first influenza pandemic of the 21st century. Studies have shown that the influenza M gene played important roles in the pathogenicity and transmissibility of the 2009 H1N1 pandemic ((H1N1)pdm09), whilst the underlying mechanism remains unclear. The influenza M gene encodes two proteins, matrix protein 1 and matrix protein 2, which play important roles in viral replication and assembly. In this study, it is found that the M2 protein of the (H1N1)pdm09 virus showed a lower mobility rate than the North America triple-reassortant influenza M2 protein in Polyacrylamide Gel Electrophoresis (PAGE). The site-directed mutations of the amino acids of (H1N1)pdm09 M2 revealed that E79 is responsible for the mobility rate change. Further animal studies showed that the (H1N1)pdm09 containing a single M2-E79K was significantly attenuated compared with the wild-type virus in mice and induced lower proinflammatory cytokines and IFNs in mouse lungs. Further in vitro studies indicated that this mutation also affected NLRP3 inflammasome activation. To reveal the reason why they have different mobility rates, a circular dichroism spectra assay was employed and showed that the two M2 proteins displayed different secondary structures. Overall, our findings suggest that M2 E79 is important for the virus replication and pathogenicity of (H1N1)pdm09 through NLRP3 inflammasome and proinflammatory response.

Eurasian Avian-like M1 Plays More Important Role than M2 in Pathogenicity of 2009 Pandemic H1N1 Influenza Virus in Mice.

Reassortant variant viruses generated between 2009 H1N1 pandemic influenza virus [A(H1N1)pdm09] and endemic swine influenza viruses posed a potential risk to humans. Surprisingly, genetic analysis showed that almost all of these variant viruses contained the M segment from A(H1N1)pdm09, which originated from Eurasian avian-like swine influenza viruses. Studies have shown that the A(H1N1)pdm09 M gene is critical for the transmissibility and pathogenicity of the variant viruses. However, the M gene encodes two proteins, M1 and M2, and which of those plays a more important role in virus pathogenicity remains unknown. In this study, the M1 and M2 genes of A(H1N1)pdm09 were replaced with those of endemic H3N2 swine influenza virus, respectively. The chimeric viruses were rescued and evaluated in vitro and in mice. Both M1 and M2 of H3N2 affected the virus replication in vitro. In mice, the introduction of H3N2 M1 attenuated the chimeric virus, where all the mice survived from the infection, compared with the wild type virus that caused 100 % mortality. However, the chimeric virus containing H3N2 M2 was still virulent to mice, and caused 16.6% mortality, as well as similar body weight loss to the wild type virus infected group. Compared with the wild type virus, the chimeric virus containing H3N2 M1 induced lower levels of inflammatory cytokines and higher levels of anti-inflammatory cytokines, whereas the chimeric virus containing H3N2 M2 induced substantial pro-inflammatory responses, but higher levels of anti-inflammatory cytokines. The study demonstrated that Eurasian avian-like M1 played a more important role than M2 in the pathogenicity of A(H1N1)pdm09 in mice.

Targeting the TLR2 Receptor With a Novel Thymopentin-Derived Peptide Modulates Immune Responses.

The innate and adaptive immune systems act in concert to protect us from infectious agents and other harmful substances. As a state of temporary or permanent immune dysfunction, immunosuppression can make an organism more susceptible to infection, organ injury, and cancer due to damage to the immune system. It takes a long time to develop new immunomodulatory agents to prevent and treat immunosuppressive diseases, with slow progress. Toll-like receptor 2 (TLR2) agonists have been reported as potential immunomodulatory candidates due to their effective activation of immune responses. It has been demonstrated that thymopentin (TP5) could modulate immunity by binding to the TLR2 receptor. However, the fairly short half-life of TP5 greatly reduces its pharmacological potential for immunosuppression therapy. Although peptide cathelicidin 2 (CATH2) has a long half-life, it shows poor immunomodulatory activity and severe cytotoxicity, which seriously hampers its clinical development. Peptide hybridization is an effective approach for the design and engineering of novel functional peptides because hybrid peptides combine the advantages and benefits of various native peptides. In this study, to overcome all these challenges faced by the parental peptides, six hybrid peptides (CaTP, CbTP, CcTP, TPCa, TPCb, and TPCc) were designed by combining the full-length TP5 with different active fragments of CATH2. CbTP, the most potent TLR2 agonist among the six hybrid peptides, was effectively screened through in silico analysis and in vitro experiments. The CbTP peptide exhibited lower cytotoxicity than either CATH2 or TP5. Furthermore, the immunomodulatory effects of CbTP were confirmed in a CTX-immunosuppressed mouse model, which showed that CbTP has increased immunopotentiating activity and physiological stability compared to the parental peptides. CbTP successfully inhibited immunosuppression and weight loss, increased immune organ indices, and improved CD4+/CD8+ T lymphocyte subsets. In addition, CbTP significantly increased the production of the cytokine TNF-α and IL-6, and the immunoglobulins IgA, IgM, and IgG. The immunoenhancing effects of CbTP were attributed to its TLR2-binding activity, promoting the formation of the TLR2 cluster, the activation of the TLR2 receptor, and thus activation of the downstream MyD88-NF-кB signaling pathway.

A highly efficient hybrid peptide ameliorates intestinal inflammation and mucosal barrier damage by neutralizing lipopolysaccharides and antagonizing the lipopolysaccharide-receptor interaction.

Intestinal inflammatory disorders, such as inflammatory bowel disease, are major contributors to mortality and morbidity in humans and animals worldwide. While some native peptides have great potential as therapeutic agents against intestinal inflammation, potential cytotoxicity, anti-inciting action, and suppression of anti-inflammatory activity may limit their development as anti-inflammatory agents. Peptide hybridization is an effective approach for the design and engineering of novel functional peptides because hybrid peptides combine the advantages and benefits of various native peptides. In the present study, a novel hybrid anti-inflammatory peptide that combines the active center of Cecropin A (C) and the core functional region of LL-37 (L) was designed [C-L peptide; C (1-8)-L (17-30)] through in silico analysis to reduce cytotoxicity and improve the anti-inflammatory activity of the parental peptides. The resulting C-L peptide exhibited lower cytotoxicity than either C or L peptides alone. C-L also exerted a protective effect against lipopolysaccharide (LPS)-induced inflammatory responses in RAW264.7 macrophages and in the intestines of a mouse model. The hybrid peptide exhibited increased anti-inflammatory activity compared to the parental peptides. C-L plays a role in protecting intestinal tissue from damage, LPS-induced weight loss, and leukocyte infiltration. In addition, C-L reduces the expression levels of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), IL-1ß, and interferon-gamma (IFN-γ), as well as reduces cell apoptosis. It also reduced mucosal barrier damage caused by LPS. The anti-inflammatory effects of the hybrid peptide were mainly attributed to its LPS-neutralizing activity and antagonizing the activation of LPS-induced Toll-like receptor 4-myeloid differentiation factor 2 (TLR4/MD2). The peptide also affected the TLR4-(nuclear factor κB) signaling pathway, modulating the inflammatory response upon LPS stimulation. Collectively, these findings suggest that the newly designed peptide, C-L, could be developed into a novel anti-inflammatory agent for animals or humans.

Acetylation at K108 of the NS1 protein is important for the replication and virulence of influenza virus.

Non-structural protein 1 (NS1) of influenza virus is a multifunctional protein that plays an important role in virus replication and virulence. In this study, an acetylation modification was identified at the K108 residue of the NS1 protein of H1N1 influenza virus. To further explore the function of the K108 acetylation modification of the NS1 protein, a deacetylation-mimic mutation (K108R) and a constant acetylation-mimic mutation (K108Q) were introduced into the NS1 protein in the background of A/WSN/1933 H1N1 (WSN), resulting in two mutant viruses (WSN-NS1-108R and WSN-NS1-108Q). In vitro and mouse studies showed that the deacetylation-mimic mutation K108R in the NS1 protein attenuated the replication and virulence of WSN-NS1-108R, while the constant acetylation-mimic mutant virus WSN-NS1-108Q showed similar replication and pathogenicity as the wild-type WSN virus (WSN-wt). The results indicated that acetylation at K108 of the NS1 protein has an important role in the replication and virulence of influenza virus. To further explore the potential mechanism, the type I interferon (IFN-I) antagonistic activity of the three NS1 proteins (NS1-108Q, NS1-108R, and NS1-wt) was compared in cells, which showed that the K108R mutation significantly attenuated the IFN-ß antagonistic activity of the NS1 protein compared with NS1-wt and NS1-108Q. Both NS1-wt and NS1-108Q inhibited the IFN-ß response activated by RIG-I CARD domain, MAVS, TBK1, and IRF3 more efficiently than the NS1-108R protein in cells. Taken together, the results indicated that acetylation at NS1 K108 is important for the IFN antagonistic activity of the NS1 protein and virulence of the influenza virus.

Isolation and characterization of an Aves polyomavirus 1 from diseased budgerigars in China.

Aves polyomavirus 1 (APV) causes inflammatory disease in psittacine birds, especially in young budgerigar. In this study, an APV virus (SD18 strain) was isolated from a diseased psittacine birds breeding facility. The full genome (4981 bp) of SD18 was determined and analyzed. Phylogenetic analysis of full genome sequences indicated all the APV strains form two groups. The SD18 strain showed close relationship with APV isolated from Poland, however, the other Chinese strains are located in group II, which suggested different genotypes APVs are co-circulating in China. Compared with the consensus sequence of APV full genome, the SD18 strain contains 13 nucleotide mutations, and 2 unique amino acid substitutions (R179M and Q382K) located in VP2/3 and Large T proteins. To explore the pathogenicity of the virus, the SD18 strain was used to challenge 2-week-old budgerigars. All infected birds died no later than 5 days post infection, and virus was detected in multiple organs including brain, heart, ingluvies, liver, and intestine, which indicated that SD18 is fatal and causes systemic infection in young budgerigar. In vitro studies showed that SD18 replicated efficiently in CEF cells and reached the highest viral titers at 9 days post infection. Notably, replication of SD18 stimulated IFN-ß response in CEF cells and overexpression of the VP4 or VP4Delta proteins significantly inhibited IFN-ß promoter activation, which could be the strategy of APV to escape from the host innate immunity.

Effects of Different Forms and Levels of Selenomethionine on Productive Performance and Antioxidant Status of Broiler Breeders and Its Offspring.

This study was conducted to investigate the effects of different selenomethionine (SM) forms and levels on productive performance and antioxidant status of broiler breeders and its offspring. Four hundred eighty 48-week-old Lingnan Yellow broiler breeders were randomly divided into four groups, provided basal diet with 0.15 or 0.30 mg/kg Se coming from two SM forms of DL-SM and L-SM. The experiment included a 4-week pretreatment period and an 8-week trial period. During the trial period, eggs were incubated once a week under standard conditions. The broiler breeders were slaughtered after the trial period. At the same time, 15 1-day-old chicks were selected at random per replicate and killed. The results showed that different SM forms and levels had no significant differences in average egg weight, feed intake, and feed-to-egg ration. The DL-SM group in contrast to the L-SM group induced a notable elevation of glutathione peroxidase (GPx) activity in serum (P < 0.01) and liver (P < 0.05), and the 0.15 mg/kg group had higher GPx activity than 0.30 mg/kg in serum (P < 0.01) and pancreas (P < 0.05). Different SM forms showed no significant differences in total antioxidant capability (T-AOC). Diets with 0.15 mg/kg Se exhibited a higher level of T-AOC in serum (P < 0.01) and some tissues. Besides, malondialdehyde (MDA) concentrations in serum, liver, and kidney significantly decreased due to the supplementation of DL-SM. Supplemental 0.15 mg/kg Se reduced MDA concentrations in kidney and muscle. The offspring of broiler breeders fed on DL-SM had higher GPx activity in liver and kidney than L-SM treatment. Supplemental 0.15 mg/kg Se also improved GPx activity in kidney and muscle and T-AOC in kidney of 1-day-old chicks. In summary, our study demonstrated that compared with L-SM, DL-SM was more effective for enhancing the antioxidant status of broiler breeders and its offspring. Moreover, the recommended level of Se supplementation was 0.15 mg/kg Se in Lingnan Yellow broiler breeder diets.

Expression, Purification, and Characterization of a Novel Hybrid Peptide with Potent Antibacterial Activity.

The hybrid peptide cecropin A (1⁻8)⁻LL37 (17⁻30) (C⁻L), derived from the sequence of cecropin A (C) and LL-37 (L), showed significantly increased antibacterial activity and minimized hemolytic activity than C and L alone. To obtain high-level production of C⁻L, the deoxyribonucleic acid sequence encoding C⁻L with preferred codons was cloned into pET-SUMO to construct a fusion expression vector, and overexpressed in Escherichia coli (E. coli) BL21 (DE3). The maximum fusion protein (92% purity) was obtained with the yield of 89.14 mg/L fermentation culture after purification with Ni-NTA Sepharose column. The hybrid C⁻L was cleaved from the fusion protein by SUMO-protease, and 17.54 mg/L pure active C⁻L was obtained. Furthermore, the purified C⁻L showed identical antibacterial and hemolytic activity to synthesized C⁻L. Stability analysis results exhibited that the activity of C⁻L changed little below 80 °C for 20 min, but when the temperature exceeded 80 °C, a significant decrease was observed. Varying the pH from 5.0 to 10.0 did not appear to influence the activity of C⁻L, however, pH below 4.0 decreased the antibacterial activity of C⁻L rapidly. Under the challenge of several proteases (pepsin, trypsin, and proteinase K), the functional activity of C⁻L was maintained over 50%. In summary, this study not only supplied an effective approach for high-level production of hybrid peptide C⁻L, but paved the way for its further exploration in controlling infectious diseases of farm animals or even humans.

Novel Hybrid Peptide Cecropin A (1-8)-LL37 (17-30) with Potential Antibacterial Activity.

Hybridizing different antimicrobial peptides (AMPs) is a particularly successful approach to obtain novel AMPs with increased antimicrobial activity but minimized cytotoxicity. The hybrid peptide cecropin A (1-8)-LL37 (17-30) (C-L) combining the hydrophobic N-terminal fragment of cecropin A (C) with the core antimicrobial fragment of LL37 (L) was designed and synthesized. C-L showed higher antibacterial activity against all indicator strains than C and L, and no hemolytic activity to sheep erythrocytes was observed. C-L kills bacterial cells and causes disruption of surface structure, as determined by scanning electron microscopy. Synergistic effects were observed in the combination of C-L with several antibiotics (chloramphenicol, thiamphenicol, or neomycin sulfate) against Escherichia coli and Staphylococcus aureus.

Effects of Clostridium butyricum on antioxidant properties, meat quality and fatty acid composition of broiler birds.

BACKGROUND: Consumers are becoming increasingly interested in food containing high concentration of polyunsaturated fatty acids (PUFA). PUFA are considered as functional ingredients to prevent cardiovascular disease. The present study aimed to evaluate the effects of Clostridium butyricum on antioxidant properties, meat quality and fatty acid composition of broilers. METHODS: A total of 320 one-day-old Arbor Acres male chicks were randomly assigned to one of five treatments with eight replicates and fed a antibiotic-free basal corn-soybean meal diet (control) or the basal diet supplemented with either 2.5 × 10(8) (CB1), 5 × 10(8) (CB2) or 1 × 10(9) (CB3) cfu of C. butyricum/kg or 150 mg of aureomycin/kg (antibiotic) for 42 days. RESULTS: The results showed that chicks fed diets supplemented with C. butyricum had higher (P < 0.05) superoxide dismutase activity and lower (P < 0.05) malondialdehyde concentration in liver compared with those in the control group. Broilers had lower (P < 0.05) cholesterol content of serum in either CB2 or CB3 treatment at day 21 and in the C. butyricum-supplemented groups at day 42 than those in the control group. Chicks fed CB3 diet had lower (P < 0.05) percentage of abdominal fat and higher (P < 0.05) breast muscle yield than those in the control and antibiotic groups. The supplementation of C. butyricum increased (P < 0.05) the concentrations of C20:1n-9, C20:2n-6, C20:3n-6, C20:3n-3, C20:4n-6, C20:5n-3, C22:6n-3 and total PUFA as well as ratio of PUFA to saturated fatty acids in breast muscle and the contents of C18:2 t-9, t-12, C20:3n-6, C20:3n-3 and C20:5n-3 in thigh muscle. CONCLUSIONS: Supplementation of C. butyricum promotes hepatic antioxidant status, decreases cholesterol content of serum and percentage of abdominal fat, and improves meat quality and fatty acid composition of broiler birds. The results from the present study indicate that the increased PUFA concentrations in meat of broilers fed C. butyricum might be attributable to enhanced antioxidant activity.

Expression of the Thermobifida fusca xylanase Xyn11A in Pichia pastoris and its characterization.

BACKGROUND: Xylan is a major component of plant cells and the most abundant hemicellulose. Xylanases degrade xylan into monomers by randomly cleaving ß-1,4-glycosidic bonds in the xylan backbone, and have widespread potential applications in various industries. The purpose of our study was to clone and express the endoxylanase gene xynA of Thermobifida fusca YX in its native form and with a C-terminal histidine (His) tag in Pichia pastoris X-33. We analyzed and compared these two forms of the protein and examined their potential applications in various industries. RESULTS: The xynA gene from T. fusca YX was successfully cloned and expressed using P. pastoris X-33. We produced a recombinant native form of the protein (rXyn11A) and a C-terminal His-tagged form of the desired protein (rXyn11A-(His)6). The specific activities of rXyn11A and rXyn11A-(His)6 in culture supernatants approached 149.4 and 133.4 U/mg, respectively. These activities were approximately 4- and 3.5-fold higher than those for the non-recombinant wild-type Xyn11A (29.3 U/mg). Following purification, the specific activities of rXyn11A and rXyn11A-(His)6 were 557.35 and 515.84 U/mg, respectively. The specific activity of rXyn11A was 8% higher than that of rXyn11A-(His)6. Both recombinant xylanases were optimally active at 80°C and pH 8.0, and exhibited greater than 60% activity between pH 6-9 and 60-80°C. They exhibited similar pH stability, while rXyn11A exhibited better thermostability; N-glycosylation enhanced the thermostability of both recombinant xylanases. The products of beechwood xylan hydrolyzed by both xylanases included xylobiose, xylotriose, xylotetraose and xylopentaose. CONCLUSIONS: The C-terminal His tag had adverse effects when added to the Xyn11A protein. The thermostability of both recombinant xylanases was enhanced by N-glycosylation. Their stabilities at a high pH and temperature indicate their potential for application in various industries.

Response surface optimization of enzymatic hydrolysis of duck blood corpuscle using commercial proteases.

With the rapid development in livestock and poultry husbandry and increasing shortage of protein sources, recycling of wastes from agricultural and food processing such as blood corpuscles has been regarded as an important industrial procedure to obtain protein sources. This study aimed to find an appropriate method for recycling the considerable amounts of blood corpuscle so as to improve its nutritional value and organoleptic quality. An effective production process for enzymatic hydrolysis of duck blood corpuscle was successfully developed and optimized by response surface methodology. Optimal conditions based on achieving a high value of trichloroacetic acid solubility index were substrate concentration of 14 g/100 mL, temperature 51°C, initial pH 7.0, and time 7.5 h. The electrophoretic patterns of the protein hydrolysate were investigated, and a large diffuse band was observed in the vicinity of 5 kDa. The organoleptic quality of spray-dried blood corpuscle hydrolysate was also evaluated, indicating that enzymatic hydrolysis and decoloration methods were feasible and cost-effective to achieve the desirable bright yellow product without bitterness. In vitro protein digestibility of blood corpuscle hydrolysate was 96.32 ± 0.50%, which was better than that of soybean, fish meal, and casein. Based on the amino acid composition and nutritional parameters, we found that the spray-dried blood corpuscle hydrolysate had abundant nutritional value and high potential for application as an ingredient in nonruminant animal feed.

Design, characterization and expression of a novel hybrid peptides melittin (1-13)-LL37 (17-30).

Hybridizing of different antimicrobial peptides (AMPs) has been a common practice for obtaining novel hybrid AMPs with elevated antibacterial activity but minimized cytotoxicity. The hybrid peptides melittin (1-13)-LL37 (17-30) (M-L) combining the hydrophobic N-terminal fragment of melittin (M) with the core antibacterial fragment of LL37 (L), was designed for the first time to explore its antibacterial activity and hemolytic activity against bacteria and sheep erythrocyte respectively. Results showed that M-L had an even more potent antibacterial activity against all indicator strains (especially gram-positive bacteria) than M and L, whereas didn't exhibit hemolytic activity to sheep erythrocytes, implying M-L can be served as a potential therapeutic drug to substitute traditional antibiotics. However the high expense of biosynthesis limited its further research, therefore fusion expression of M-L was carried out in Escherichia coli (E. coli) for overproducing the hybrid peptide so as to solve the problem. The DNA sequence encoding M-L with preferred codons was cloned into the pET-SUMO vector for protein expression in E. coli BL21 (DE3). After IPTG induction, approximately 165 mg soluble fusion protein SUMO-M-L was recovered per liter supernatant of the fermentation ultrasonic lysate using Ni-NTA Sepharose column (92 % purity). And 23 mg recombinant M-L was obtained per liter culture after cleavage of SUMO protease and purification of Ni-NTA Sepharose column. In sum, this research not only supplied an effective approach for overproducing hybrid peptide M-L, but paved the way for its further exploration on pharmaceutical potential and medical importance.

High-level overproduction of Thermobifida enzyme in Streptomyces lividans using a novel expression vector.

In this study, we constructed a novel Streptomyces-E.coli shuttle vector pZRJ362 combining the xylose isomerase promoter and amylase terminator. A gene encoding the endoglucanase Cel6A in Thermobifida fusca was amplified by PCR, cloned into Streptomyces lividans host strain using the novel expression vector and Pichia pastoris GS115 host strain using the vector pPICZα-C, respectively. Afterwards, the expression pattern and the maximum expression level were comparatively studied in both expression systems. The maximum enzyme activity of Cel6A-(His)6 secreted in S. lividans supernatant after 84-h of cultivation amounted to 5.56 U/mL, which was dramatically higher than that secreted in P. pastoris about 1.4 U/mL after 96-h of cultivation. The maximum expression level of Cel6A-(His)6 in S. lividans supernatant reached up to 173 mg/L after 84-h of cultivation. The endoglucanase activity staining SDS-PAGE showed that there were some minor proteins in S. lividans supernatant which may be the Cel6A derivant by proteolytic degradation, while there was no proteolytic product detected in supernatant of P. pastoris.

Influence of dietary selenomethionine supplementation on performance and selenium status of broiler breeders and their subsequent progeny.

The study was conducted to investigate the effects of dietary maternal selenomethionine or sodium selenite supplementation on performance and selenium status of broiler breeders and their next generation. Two hundred and forty 39-week-old Lingnan yellow broiler breeders were allocated randomly into two treatments, each of which included three replicates of 40 birds. Pretreatment period was 2 weeks, and the experiment lasted 8 weeks. The groups were fed the same basal diet supplemented with 0.30 mg selenium/kg of sodium selenite or selenomethionine. After incubation, 180 chicks from the same parental treatment group were randomly divided into three replicates, with 60 birds per replicate. All the offspring were fed the same diet containing 0.04 mg selenium/kg, and the experiment also lasted 8 weeks. Birth rate was greater (p < 0.05) in hens fed with selenomethionine than that in hens fed with sodium selenite. The selenium concentration in serum, liver, kidney, and breast muscle of broiler breeders, selenium deposition in the yolk, and albumen and tissues' (liver, kidney, breast muscle) selenium concentrations of 1-day-old chicks were significantly (p < 0.01) increased by maternal selenomethionine supplementation compared with maternal sodium selenite supplementation. The antioxidant status of 1-day-old chicks was greatly improved by maternal selenomethionine intake in comparison with maternal sodium selenite intake and was evidenced by the increased glutathione peroxidase activity in breast muscle (p < 0.05), superoxide dismutase activity in breast muscle and kidney (p < 0.05), glutathione concentration in kidney (p < 0.01), total antioxidant capability in breast muscle and liver (p < 0.05), and decreased malondialdehyde concentration in liver and pancreas (p < 0.05) of 1-day-old chicks. Feed utilization was better (p < 0.05), and mortality was lower (p < 0.05) in the progeny from hens fed with selenomethionine throughout the 8-week growing period compared with those from hens fed with sodium selenite. In summary, we concluded that maternal selenomethionine supplementation increased birth rate and Se deposition in serum and tissues of broiler breeders as well as in egg yolk and egg albumen more than maternal sodium selenite supplementation. Furthermore, maternal selenomethionine intake was also superior to maternal sodium selenite intake in improving the tissues Se deposition and antioxidant status of 1-day-old chicks and increasing the performance of the progeny during 8 weeks of post-hatch life.

Comparison of different forms of dietary selenium supplementation on growth performance, meat quality, selenium deposition, and antioxidant property in broilers.

This study was conducted to investigate the effects of different sources of dietary selenium (Se) supplementation on growth performance, meat quality, Se deposition, and antioxidant property in broilers. A total of 600 one-day-old Ross 308 broilers with an average body weight (BW) of 44.30 ± 0.49 g were randomly allotted to three treatments, each of which included five replicates of 40 birds. These three groups received the same basal diet containing 0.04 mg Se/kg, supplemented with 0.15 mg Se/kg from sodium selenite (SS) or from L-selenomethionine (L-Se-methionine (Met)) or from D-selenomethionine (D-Se-Met). The experiment lasted 42 days. Both Se source and time significantly influenced (p < 0.01) drip loss of breast muscle. Supplementation with L-Se-Met and D-Se-Met were more effective (p < 0.05) in decreasing drip loss than SS. Besides, the pH value of breast muscle was also significantly influenced (p < 0.05) by time. The SS-supplemented diet increased more (p < 0.05) liver, kidney, and pancreas glutathione peroxidase (GSH-Px) activities than the D-Se-Met-supplemented diet. In addition, L-Se-Met increased more (p < 0.01) liver and pancreas GSH-Px activities than D-Se-Met. The antioxidant status was greatly improved in broilers of L-Se-Met-treated group in comparison with the SS-treated group and was illuminated by the increased glutathione (GSH) concentration in serum, liver, and breast muscle (p < 0.05); superoxide dismutase (SOD) activity in liver (p < 0.01); total antioxidant capability (T-AOC) in kidney, pancreas, and breast muscle (p < 0.05) and decreased malondialdehyde (MDA) concentration in kidney and breast muscle (p < 0.05) of broilers. Besides, supplementation with D-Se-Met was more effective (p < 0.01) in increasing serum GSH concentration and decreasing breast muscle MDA concentration than SS. L-Selenomethionine supplementation significantly increased GSH concentration in liver and breast muscle (p < 0.05); SOD activity in liver (p < 0.01); and T-AOC in liver, pancreas, and breast muscle (p < 0.05) of broilers, compared with broilers fed D-Se-Met diet. The addition of L-Se-Met and D-Se-Met increased (p < 0.01) Se concentration in serum and different organs studied of broilers in comparision with broilers fed SS diet. Therefore, dietary L-Se-Met and D-Se-Met supplementation could improve antioxidant capability and Se deposition in serum and tissues and reduce drip loss of breast muscle in broilers compared with SS. Besides, L-Se-Met is more effective than D-Se-Met in improving antioxidant status in broilers.

Effect of different selemethionine forms and levels on performance of breeder hens and se distribution of tissue and egg inclusion.

A 2×2 factorial arrangement of treatments in randomized design was conducted to investigate the effect of different selenomethionine (SM) sources and levels on the productive performance of breeder hens and the Se distribution in the inclusion of eggs and serum and tissues of breeder hens and its offspring. A total of 480 Ling-Nan-Huang breeder hens, 48 weeks of age, were allocated to four treatments, each of which included three replicates of 40 hens. Pretreatment period was 2 weeks, and the experiment lasted 8 weeks. Two SM forms of DL-SM and L-SM were supplemented at 0.15 or 0.30 mg Se/kg into the basal diet. Results showed that the Se level of 0.15 mg/kg supplemented in the diet, compared to 0.30 mg/kg, significantly elevated the percentage of egg production (p<0.05), hatchability (p<0.01), and birthrate (p<0.01), whereas the Se level of 0.30 mg/kg led to a higher Se content in egg contents, serum, and all tissues (p<0.01). In addition, the form of DL-SM showed a significant increase in Se content of egg inclusion (p<0.01), serum (p<0.01), and all tissues (p<0.01, except breeder hens' pancreas and its offspring's liver and breast muscle). The birthrate and yolk Se content were markedly influenced by the interaction between Se source and Se level (p<0.01). The above results suggested that DL-SM, compared to L-SM, had a similar equal effect on the performance of breeder hens, but DL-SM was superior to L-SM with respect to selenium distribution in egg inclusion, serum, and tissues.