The effects of dietary Selenium-yeast level on glutathione peroxidase activity, tissue Selenium content, growth performance, and carcass and meat quality of broilers

Effects of high-dose selenium-enriched Saccharomyces cerevisiae on growth performance, antioxidant status, tissue fat content and selenium concentration, and selenoenzyme mRNA expression in chicks

Selenium-enriched Saccharomyces cerevisiae (SSC) as organic selenium (Se) has been shown to have better advantages and is approved for use in animal feed rather than inorganic Se, however, there is little available data on the toxic effects of SSC on poultry. The present study was conducted to investigate the effects of high-dose SSC on growth performance, antioxidant status, tissue fat content and Se concentration, and selenoenzyme mRNA expression in chicks. A total of 500, 1-day-old SPF chicks were randomly divided into 5 groups with 10 replicates of 10 chicks each. Group 1 served as a control and was fed a basal diet supplemented with 0.15 mg/kg Se from sodium selenite (SS), group 2 was fed the basic diet supplemented with 1.5 mg/kg Se from SS, while groups 3, 4, and 5 were fed the basal diet supplemented with 1.5, 5 and 10 mg/kg Se from SSC, respectively. The results showed that SS and SSC supplementation significantly affected the average daily feed intake (ADFI), feed/gain ratio (FCR), glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities, total antioxidant capacity (T-AOC), malondialdehyde (MDA) content, tissue fat content and Se concentration, and GPx1 and GPx4 mRNA levels compared with the control group (P < 0.05). Compared with group 2, group 3 exhibited higher GPx and SOD activities, tissue Se concentration, and lower MDA content on d 30, and higher Se concentration, GPx1 mRNA levels in liver and breast muscle and GPx4 mRNA levels in liver and thigh muscle, and lower MDA content on d 60 (P < 0.05). The results of correlation analysis showed that high-dose SSC supplementation was positively correlated with AFDI, FCR, MDA content, and tissue Se concentration, and negatively correlated with GPx and SOD activities, T-AOC, GPx1 and GPx4 mRNA levels in tissues. In conclusion, up to 1.5 mg/kg Se from SSC in diet may be a safe concentration for chicks that exhibited better biological effects than SS, the toxic effects of high-dose SSC supplementation mainly exhibited growth decrease, peroxidation and lipid metabolism disturbance, and became stronger with the increase of dietary Se levels.

Comparative effects of various dietary selenium sources on growth performance, meat quality, essential trace elements content, and antioxidant capacity in broilers

This study aimed to compare the effects of various dietary selenium (Se) sources (0.5 mg/kg) on performance, meat quality, and antioxidant capacity in broilers as well as essential trace elements concentrations in their blood and tissues. A total of 360 one-day-old male yellow-feathered chickens (37.00 ± 0.17 g) were randomly allocated to 5 diet treatments: the basal diet (CON) and 4 diets supplemented with sodium selenite (SS), selenomethionine (SM), selenium-enriched yeast (SY), and nano-selenium (NS) for 56 d, respectively, with 6 replicates per treatment and 12 chickens per replicate. Dietary Se supplementation did not affect growth performance and carcass characteristics in broilers (P > 0.05). Supplemental SM enhanced the redness in the pectoral muscle compared to CON and NS (P < 0.05). Supplementation of SY and NS improved the concentrations of Se, copper, manganese, and zinc in the serum (P < 0.05). Supplemental SS also elevated the zinc content in the serum (P < 0.05). Broilers fed the SY diet showed increased Se content in the liver and pectoral muscle compared to those fed CON, SM, and NS diets (P < 0.05). Also, SY improved the pectoral muscle Se concentration compared to SS (P < 0.05). Besides, dietary Se supplementation increased the Se content in the thigh muscle (P < 0.05), with SY showing highest Se deposition. Dietary supplementation with SS, SM, and NS improved the activities of total superoxide dismutase and total antioxidant capacity (T-AOC) in the serum (P < 0.05). Supplemental SY also elevated the T-AOC in the serum (P < 0.05). Additionally, SS and SM enhanced the T-AOC in the liver (P < 0.05). In conclusion, supplemental SM affected meat color. Supplementing diets with various Se sources increased antioxidant capacity and Se content in the thigh muscle of broilers, with SY showing a more pronounced deposition efficiency. Besides, diets supplemented with different Se sources had variable effects on the concentrations of essential trace elements in the serum and tissues of broilers.

Epistasis, core-genome disharmony, and adaptation in recombining bacteria

Recombination of short DNA fragments via horizontal gene transfer (HGT) can introduce beneficial alleles, create genomic disharmony through negative epistasis, and create adaptive gene combinations through positive epistasis. For non-core (accessory) genes, the negative epistatic cost is likely to be minimal because the incoming genes have not co-evolved with the recipient genome and are frequently observed as tightly linked cassettes with major effects. By contrast, interspecific recombination in the core genome is expected to be rare because disruptive allelic replacement is likely to introduce negative epistasis. Why then is homologous recombination common in the core of bacterial genomes? To understand this enigma, we take advantage of an exceptional model system, the common enteric pathogens Campylobacter jejuni and C. coli that are known for very high magnitude interspecies gene flow in the core genome. As expected, HGT does indeed disrupt co-adapted allele pairings, indirect evidence of negative epistasis. However, multiple HGT events enable recovery of the genome's co-adaption between introgressing alleles, even in core metabolism genes (e.g., formate dehydrogenase). These findings demonstrate that, even for complex traits, genetic coalitions can be decoupled, transferred, and independently reinstated in a new genetic background-facilitating transition between fitness peaks. In this example, the two-step recombinational process is associated with C. coli that are adapted to the agricultural niche.IMPORTANCEGenetic exchange among bacteria shapes the microbial world. From the acquisition of antimicrobial resistance genes to fundamental questions about the nature of bacterial species, this powerful evolutionary force has preoccupied scientists for decades. However, the mixing of genes between species rests on a paradox: 0n one hand, promoting adaptation by conferring novel functionality; on the other, potentially introducing disharmonious gene combinations (negative epistasis) that will be selected against. Taking an interdisciplinary approach to analyze natural populations of the enteric bacteria Campylobacter, an ideal example of long-range admixture, we demonstrate that genes can independently transfer across species boundaries and rejoin in functional networks in a recipient genome. The positive impact of two-gene interactions appears to be adaptive by expanding metabolic capacity and facilitating niche shifts through interspecific hybridization. This challenges conventional ideas and highlights the possibility of multiple-step evolution of multi-gene traits by interspecific introgression.

Assessing the Impacts of Different Levels of Nano-Selenium on Growth Performance, Serum Metabolites, and Gene Expression in Heat-Stressed Growing Quails

Nano-minerals are employed to enhance mineral bioavailability thus promoting the growth and well-being of animals. In recent times, nano-selenium (nano-Se) has garnered significant attention within the scientific community owing to its potential advantages in the context of poultry. This study was conducted to explore the impact of using variable levels of nano-Se on the growth performance, carcass characteristics, serum constituents, and gene expression in growing Japanese quails under both thermoneutral and heat stress conditions. A randomized experimental design was used in a 2 × 3 factorial, with 2 environmental conditions (thermoneutral and heat stress) and 3 nano-Se levels (0, 0.2, and 0.5 mg/kg of diet. The findings revealed that heat stress negatively affected the growth and feed utilization of quails; indicated by the poor BWG and FCR. Additionally, oxidative stress was aggravated under heat stress condition; indicated by increased lipids peroxidation and decreased antioxidant enzymes activities. The addition of nano-Se, especially at the level of 0.2 mg/kg of diet, significantly improved the performance of heat stressed quails and restored blood oxidative status. The expression profile of inflammatory and antioxidant markers was modulated by heat stress and/or 0.2 and 0.5 nano-Se in conjunction with environmental temperature in quail groups. In comparison to the control group, the heat stress-exposed quails' expression profiles of IL-2, IL-4, IL-6, and IL-8 showed a notable up-regulation. Significantly lower levels of the genes for IL-2, IL-4, IL-6, and IL-8 and higher levels of the genes for SOD and GPX as compared to the heat stress group demonstrated the ameliorative impact of 0.2 nano-Se. The expression profiles of IL-2, IL-4, IL-6, and IL-8 are dramatically elevated in quails exposed to 0.5 nano-Se when compared to the control group. SOD and GPX markers, on the other hand, were markedly down-regulated. It was concluded that nano-Se by low level in heat stressed growing quails provides the greatest performance and its supplementation can be considered as a protective management practice in Japanese quail diets to reduce the negative impact of heat stress.

Exploring effects of organic selenium supplementation on pork loin: Se content, meat quality, antioxidant capacity, and metabolomic profiling during storage

This research was conducted to study the effects of organic selenium (Se) supplements at different levels on pork loin quality during storage. Fifteen pork loins were procured randomly from three groups, Con (fed basal diet), Se15 (fed 0.15 ppm organic Se along with 0.10 ppm inorganic Se), and Se45 (fed 0.45 ppm organic Se along with 0.10 ppm inorganic Se). Each sample was analyzed for Se contents, antioxidant properties (glutathione peroxidase [GPx] activity, 2,2'-azinobis-[3-ethylbenzothiazoline-6-sulfonic acid] [ABTS] and 2,2-diphenyl-1-picrylhydrazyl [DPPH] radical scavenging activities, 2-thiobarbituric acid reactive substances), physicochemical properties (water holding capacity, pH, color), and metabolomic analysis during 14-day storage period. Se45-supplemented group showed significantly higher Se contents and GPx activity than the other groups throughout the storage period. However, other antioxidant properties were not significantly affected by Se supplementation. Selenium supplementation did not have an adverse impact on physicochemical properties. Nuclear Magnetic Resonance-based metabolomic analysis indicated that the selenium supply conditions were insufficient to induce metabolic change. These results suggest that organic Se (0.15 and 0.45 ppm) can accumulate high Se content in pork loins without compromising quality.

Metabolomic analysis reveals biogenic selenium nanoparticles improve the meat quality of thigh muscle in heat-stressed broilers is related to the regulation of ferroptosis pathway

Heat stress (HS) causes oxidative damage and abnormal metabolism of muscle, thus impairing the meat quality in broilers. Selenium is an indispensable element for enhancing antioxidant systems. In our previous study, we synthesized a novel type of biogenic selenium nanoparticles synthesized with alginate oligosaccharides (SeNPs-AOS), and found that the particle size of Se is 80 nm and the Se content is 8% in the SeNPs-AOS; and dietary 5 mg/kg SeNPs-AOS has been shown to be effective against HS in broilers. However, whether SeNPs-AOS can mitigate HS-induced the impairment of thigh muscle quality in broilers is still unclear. Therefore, the purpose of this study was to investigate the protective effects of dietary SeNPs-AOS on meat quality, antioxidant capacity, and metabolomics of thigh muscle in broilers under HS. A total of 192 twenty-one-day-old Arbor Acres broilers were randomly divided into 4 groups with 6 replicates per group (8 broilers per replicate) according to a 2 × 2 experimental design: thermoneutral group (TN, broilers raised under 23±1.5°C); TN+SeNPs-AOS group (TN group supplemented 5 mg/kg SeNPS-AOS); HS group (broilers raised under 33 ± 2°C for 10 h/d); and HS + SeNPs-AOS group (HS group supplemented 5 mg/kg SeNPS-AOS). The results showed that HS increased the freezing loss, cooking loss, and malondialdehyde (MDA) content of thigh muscle, whereas decreased the total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) activities, as well as downregulated the mRNA expression of SOD2, CAT, GPX3, nuclear factor erythroid 2-related factor 2 (Nrf2), selenoprotein S (SELENOS), solute carrier family 7 member 11 (SLC7A11), GPX4, and ferroportin 1 (Fpn1) of thigh muscle (P < 0.05). Dietary SeNPS-AOS reduced the b* value, elevated the pH0min value and the activities of T-SOD, GSH-Px, glutathione S-transferase (GST) and the mRNA expression levels of GSTT1, GSTA3, GPX1, GPX3, ferritin heavy polypeptide-1 (FTH1), and Fpn1 of thigh muscle in broilers under HS (P < 0.05). Nontargeted metabolomics analysis identified a total of 79 metabolites with significant differences among the four groups, and the differential metabolites were mainly enriched in 8 metabolic pathways including glutathione metabolism and ferroptosis (P < 0.05). In summary, dietary 5 mg/kg SeNPs-AOS (Se content of 8%) could alleviate HS-induced impairment of meat quality by improving the oxidative damage, metabolic disorders and ferroptosis of thigh muscle in broilers challenged with HS. Suggesting that the SeNPs-AOS may be used as a novel nano-modifier for meat quality in broilers raised in thermal environment.

Meta-analysis of selenium effects on the meat quality of broilers

The effects of sodium selenite or selenium yeast on the meat quality of broilers were searched in the literature published in the Chinese National Knowledge Infrastructure (CNKI), Wanfang Database, China Science and Technology Journal Database (VIP), PubMed, Web of Science, and Science Direct databases from January 1, 2010 to December 31, 2022. Meta-analysis was performed with Stata software (StataCorp. 2011), and the standardized mean difference (SMD) and its 95% confidence interval (CI) were calculated using a random effects model. Twenty of the identified 846 literature sources, which included 791 broilers, were screened. The meat quality indices considered were shear force, drip loss, cooking loss, water holding capacity (WHC), pH, and color. The source of heterogeneity was studied using sensitivity and subgroup analyses, and publication bias was evaluated using funnel plots. The results showed that the supplementation of selenium in the broiler diet significantly reduced the shear force (SMD = -0.67, 95% CI [-1.12, -0.22], P < 0.05) and drip loss (SMD = -0.84, 95% CI [-1.39, -0.30], P < 0.05) and increased the pH (SMD = 0.38, 95% CI [0.01, 0.75], P < 0.05) of broiler breast muscle; however, it had no significant effects on other indices. Funnel plots revealed a slight publication bias in the shear force and pH of breast muscle but none in the drip loss of breast muscle. The sensitivity analysis showed that the results were stable and reliable. In conclusion, selenium supplementation in broiler feed can improve some indices of broiler meat quality, and its inclusion in broiler diets is recommended, in conjunction with other minerals, which is of great significance to improve the quality, preservation time and economic benefits of chicken products.

Selenium yeast improve growth, serum biochemical indices, metabolic ability, antioxidant capacity and immunity in black carp Mylopharyngodnpiceus

This experiment was conducted to investigate the impacts of dietary selenium yeast (SeY) on the growth performance, fish body composition, metabolic ability, antioxidant capability, immunity and inflammatory responses in juvenile black carp (Mylopharyngodn piceus). The base diet was supplemented with 0.00, 0.30 and 0.60 g/kg SeY (0.04, 0.59 and 1.15 mg/kg of selenium) to form three isonitrogenous and isoenergetic diets for juvenile black carp with a 60-day. Adequate dietary SeY (0.30 and 0.60 g/kg) could significantly increase the weight gain (WG), special growth rate (SGR) compared to the SeY deficient groups (0.00 g/kg) (P < 0.05). Meanwhile, 0.30 and 0.60 g/kg SeY elevated the mRNA levels of selenoprotein T2 (SEPT2), selenoprotein H (SEPH), selenoprotein S (SEPS) and selenoprotein M (SEPM) in the liver and intestine compared with the SeY deficient groups (P < 0.05). Adequate dietary SeY could promote glucose catabolism and utilization through activating glucose transport (GLUT2), glycolysis (GCK, HK, PFK, PK, PDH), tricarboxylic acid cycle (ICDH and MDH), glycogen synthesis (LG, GCS and GBE) and IRS/PI3K/AKT signal pathway molecules (IRS2b, PI3Kc and AKT1) compared with the SeY deficient groups (P < 0.05). Similarly, adequate dietary SeY could improve lipid transport and triglycerides (TG) synthesis through increasing transcription amounts of CD36, GK, DGAT, ACC and FAS in the fish liver compared with the SeY deficient groups (P < 0.05). In addition, adequate SeY could markedly elevate activities of antioxidant enzymes (T-SOD, CAT, GR, GPX) and contents of T-AOC and GSH, while increased transcription amounts of Nrf2, Cu/Zn-SOD, CAT, and GPX in fish liver and intestine (P < 0.05). However, adequate SeY notably decreased contents of MDA, and the mRNA transcription levels of Keap1 in the intestine compared with the SeY deficient groups (P < 0.05). Adequate SeY markedly increased amounts or levels of the immune factors (ALP, ACP, LZM, C3, C4 and IgM) and the transcription levels of innate immune-related functional genes in the liver and intestine (LZM, C3 and C9) compared to the SeY deficient groups (P < 0.05). Moreover, adequate SeY could notably reduce levels of IL-8, IL-1β, and IFN-γ and elevate TGF-1β levels in fish intestine (P < 0.05). The transcription levels of MAPK13, MAPK14 and NF-κB p65 were notably reduced in fish intestine treated with 0.30 and 0.60 g/kg SeY (P < 0.05). In conclusion, these results suggested that 0.30 and 0.60 g/kg SeY could not only improve growth performance, increase Se, glucose and lipid metabolic abilities, enhance antioxidant capabilities and immune responses, but also alleviate inflammation, thereby supplying useful reference for producing artificial feeds in black carp.

In ovo feeding of l-arginine and selenium nanoparticles influences post-hatch growth, muscle development, antioxidant status, and meat quality in slow-growing chickens

This study investigated the effects of in ovo feeding (IOF) of l-arginine (L-Arg), selenium nanoparticles (SeNP), and a combination of L-Arg and SeNP on the hatchability, post-hatch growth, muscle development, antioxidant status, and meat quality of slow-growing chickens. On day 18 of incubation, a total of 960 fertilized eggs with similar weights were randomly assigned to 4 treatment groups with 4 replicates of 60 eggs each: (1) non-injected control group (Control), (2) injected with 1% of L-Arg (IOF_L-Arg), (3) injected with 0.3 µg/egg of SeNP (IOF_SeNP), and (4), injected with 1% of L-Arg and 0.3 µg/egg of SeNP (IOF_L-Arg + SeNP). A completely randomized design was used. After hatching, 640 mixed-sex chicks were allocated to 4 treatment groups and split into 4 replicate pens (40 birds per pen). All groups of chicks were fed with commercial feed ad libitum until they reached 63 d of age and were subsequently weighed and slaughtered. The results of the present study showed that hatchability was similar among treatments. Final BW or breast muscle yield was not affected (P > 0.05) by IOF treatment. Chickens treated with IOF_L-Arg + SeNP exhibited decreased feed conversion ratio, drip loss, and increased protein content in breast meat (P < 0.05). The IOF_L-Arg + SeNP group exhibited a higher density of breast muscle fibers than the control group (P < 0.05). Overall, in ovo feeding of L-Arg combined with SeNP resulted in improved feed efficiency and enhanced antioxidant capacity at hatch without any adverse effects on chicken hatchability, health, or subsequent growth. Furthermore, meat from chickens in the IOF_L-Arg + SeNP group exhibited a preferable texture with a higher protein content.

Effects of Selenium Dietary Yeast on Growth Performance, Slaughter Performance, Antioxidant Capacity, and Selenium Deposition in Broiler Chickens

Selenium (Se) yeast, a bioavailable form of selenium, exhibits enhanced bioavailability due to its unique organic matrix and superior metabolic availability compared to the inorganic selenium sources. This study aims to evaluate the effects of Se yeast on the growth performance, slaughter performance, antioxidant capacity, and Se deposition in broiler chickens. A total of 264 1-day-old male AA broilers (38.7 ± 0.1 g) were randomly assigned to four treatment groups, with six replicates of 11 chickens per replicate. The broilers were fed a basal diet or a diet supplemented with 0.1, 0.2, and 0.4 mg/kg Se yeast. The experiment lasted for 42 days. Although the results showed that Se yeast did not significantly improve the growth performance of broilers, it did significantly decrease the abdominal fat ratio. Additionally, supplementation of Se yeast significantly improved the antioxidant capacity of broilers. The quadratic regression models were used to simulate the relationship between Se content in the feed and Se deposition in broiler tissues. The regression equations were as follows: pectoral muscle, Y = 2.628X - 0.340X2 - 0.592 (R2 = 0.927); leg muscle, Y = 2.317X - 0.272X2 - 0.490 (R2 = 0.937); liver, Y = 3.357X - 0.453X2 - 0.493 (R2 = 0.961); kidney, Y = 4.084X - 0.649X2 + 0.792 (R2 = 0.932). Based on these findings, the Se deposition in broiler tissues can be predicted by the Se content of the additive, which is of great significance for the precise production of Se-enriched functional chicken products.

The influence of bacterial selenium nanoparticles biosynthesized by Bacillus subtilus DA20 on blood constituents, growth performance, carcass traits, and gut microbiota of broiler chickens

Selenium is one of the necessary micronutrients needed for enhanced gut microbiota and oxidative stress of poultry, so it improves their performance. In this study, Bacillus subtilus DA20 isolate that identified at the gene level by PCR was employed to produce eco-friendly selenium nanoparticles (BSeNPs) and investigate their effects on growth performance, carcass characteristics, blood parameters, and gut microbiota of Indian River (IR) broiler chickens. The obtained selenium nanoparticles were spherical with size of 56 nm and net negative charge of -22.36 mV; the BSeNPs were surrounded with active compounds, which besides the tiny size attributed to antioxidant and antibacterial activity. Forty hundred and eighty unsexed IR broilers, 1-day old, were reared for 35 d. The chicks were weighed separately and distributed into 3 treatment groups; each group contained 4 replicates (40 birds per replicate). Chicks in the first, second, third, fourth groups were fed control diets supplemented with 0, 20, 40, and 60 µg/kg of BSeNPs, respectively; but the fifth group was fed 300 µg/kg bulk selenium. Dietary supplementation with BSeNPs (40 µg/kg diet) significantly increased the body weight of chicks and decreased the feed conversion ratio. Additionally, dietary BSeNPs significantly (P = 0.046) lowered the fat content in broiler by 24% compared to the control; on the other hand, the breast muscle significantly increased (P = 0.035) by 19%. The content of total bacterial count (TBC), total yeast mold count (TYMC), E. coli, and Salmonella counts significantly was decreased with BSeNPs and Se compared to the control. However, lactic acid bacteria (LAB) was significantly increased with BSeNPs (60 μg/kg) when compared to control, showing the beneficial effects of BSeNPs in reducing pathogens and enhancing the beneficial bacteria, which reflects on the broiler performance.

Efficacy of Dietary Supplementation with Zinc-Chromium Mixture, Organic Selenium, or Their Combinations on Growth Performance, Carcass Traits, and Blood Profiles of Broilers under Heat Stress Conditions

To determine the effects of organic selenium (0.0-0.6 mg and 0.9 mg Se/Kg diet) and Zn-Cr mixture (100 mg Zn/Kg diet plus 1.5 mg Cr/Kg diet) on broiler chicken performance, carcass traits, blood hematology, and biochemistry under heat stress conditions, this study was conducted. Under temperatures between 30.21 to 31.82 °C, 240 broiler chickens (Ross-308), which were 7-day-old, were randomly assigned to one of six treatments: T1 (control), T2 (100 mg Zn per kg of diet and 1.5 mg Cr per kg of diet), T3 (0.6 mg Se per kg of diet), T4 (0.9 mg Se per kg of diet), T5 (100 mg Zn, 1.5 mg Cr and (LSe), and T6 (100 mg Zn, 1.5 mg Cr and (HSe)). At 35 days old, the chicks fed a diet containing Zn-Cr with low or high organic selenium (organic-Se) outweighed the control group in terms of live body weight, weight gain, and feed conversion ratio (p < 0.05). In comparison to the control treatment, birds fed diets supplemented with Zn-Cr or organic-Se (LSe, HSe) significantly increased their serum levels of total protein and total antioxidant capacity. However, these additives resulted in a decrease (p < 0.01) in their serum levels of triglycerides, total cholesterol, low-density lipoprotein (LDL) cholesterol, creatinine, and uric acid. Together, it was found that trace elements (Zn-Cr and organic-Se) may greatly lessen the impacts of heat stress on broilers by promoting growth performance and boosting metabolic processes.

Analysis of growth performance and carcass and meat quality of different crossbreeds of Cherry Valley duck

Duck breeding and production are facing great opportunities in China, as the market for small-sized high-quality duck is rapidly expanding. Therefore, breeding the most suitable genetic stock has become an important goal.This study assessed body and carcass weight, slaughter rate and meat quality of offspring of three cross combinations; Cherry Valley duck (CV♂) × Small-sized Pekin duck (PK♀), CV♂×Taiwan white duck (TW♀), CV♂×Putian white duck (PT♀) and the corresponding pure lines at 56 d of age. These 420 ducks were raised in seven separate groups (10 pens/group, 3♂+3♀/pen).Body and carcass weights were significantly lower in the three cross combinations than CV ducks (P=0.042 and P=0.012). Abdominal fat and sebum weight were lowest in CV♂×PK♀, whereas the breast and the leg muscle weights were significantly higher in CV♂×PK♀ compared to CV♂×TW♀ and CV♂×PT♀ (P=0.018 and P=0.023). No difference was observed in the visceral tissues among the three cross combinations or compared to CV ducks.The performance indicators suggested that CV♂×PK♀, CV♂×TW♀ and CV♂×PT♀ cross combinations are best suited for segmented duck meat, featured duck meat and whole-duck processing, respectively.

New horizons for selenium in animal nutrition and functional foods

Selenium (Se), one of the indispensable nutrients for both human health and animal growth, participates in various physiological functions, such as antioxidant and immune responses and metabolism. The role of dietary Se, in its organic and inorganic forms, has been well documented in domestic animals. Furthermore, many feeding strategies for different animals have been developed to increase the Se concentration in animal products to address Se deficiency and even as a potential nutritional strategy to treat free radical-associated diseases. Nevertheless, studies on investigating the optimum addition of Se in feed, the long-term consequences of Se usage in food for animal nutrition, the mechanism of metallic Se nanoparticle (SeNP) transformation in vivo, and the nutritional effects of SeNPs on feed workers and the environment are urgently needed. Starting from the absorption and metabolism mechanism of Se, this review discusses the antioxidant role of Se in detail. Based on this characteristic, we further investigated the application of Se in animal health and described some unresolved issues and unanswered questions warranting further investigation. This review is expected to provide a theoretical reference for improving the quality of food animal meat as well as for the development of Se-based biological nutrition enhancement technology.

Effects of selenium yeast and jujube powder dietary supplements on conformational and functional properties of post-mortem chicken myofibrillar protein

The aim of the study was to evaluate the effects of selenium yeast and jujube powder on the structure and functional properties of post-mortem myofibrillar protein (MP) in white feather broilers. Changes in the structure (surface hydrophobicity, secondary structure, and tertiary structure), functional properties (solubility, turbidity, emulsifying, and foaming characteristics), and gel properties (gel strength, springiness, and water-holding capacity) of the MPs of white feather broiler, which were fed with different concentrations of selenium yeast or/and jujube powder (selenium yeast: 0,0.3, and 0.6 mg/kg; jujube powder: 8% to replace corn) for 42 days, were determined at 0, 24, and 72 h post-mortem. The results showed that with increasing concentrations of selenium yeast and jujube powder in the diet, the α-helix content, solubility, emulsification, and foaming of post-mortem chicken MP increased significantly (P < 0.05). The gel strength, springiness, and water-holding capacity of MP also increased, but the differences between the treatment groups were not significant (P > 0.05). In addition, the β-folding content and turbidity of MP decreased significantly (P < 0.05). Both the increase in selenium yeast levels and the addition of jujube powder improved the structural integrity and functional properties of MP. The best improvement effect was found in the combination group of high-dose selenium yeast and jujube powder, and there were significant interactions between them in the indices of α-helix, β-folding, turbidity, emulsification, and foam stability of MP. In conclusion, supplementing diets with seleniumyeast and jujube powder could maintain the structural stability of MPs in post-mortem chicken breast, leading to good functional properties. The results of this study may provide new insights into the effects of pre-slaughter feeding on post-mortem muscle MP conformation control and quality improvement.

Influences of Dietary Vitamin E, Selenium-Enriched Yeast, and Soy Isoflavone Supplementation on Growth Performance, Antioxidant Capacity, Carcass Traits, Meat Quality and Gut Microbiota in Finishing Pigs

This study investigated the effects of dietary compound antioxidants on growth performance, antioxidant capacity, carcass traits, meat quality, and gut microbiota in finishing pigs. A total of 36 barrows were randomly assigned to 2 treatments with 6 replicates. The pigs were fed with a basal diet (control) or the basal diet supplemented with 200 mg/kg vitamin E, 0.3 mg/kg selenium-enriched yeast, and 20 mg/kg soy isoflavone. Dietary compound antioxidants decreased the average daily feed intake (ADFI) and feed to gain ratio (F/G) at d 14−28 in finishing pigs (p < 0.05). The plasma total protein, urea nitrogen, triglyceride, and malondialdehyde (MDA) concentrations were decreased while the plasma glutathione (GSH) to glutathione oxidized (GSSG) ratio (GSH/GSSG) was increased by compound antioxidants (p < 0.05). Dietary compound antioxidants increased loin area and b* value at 45 min, decreased backfat thickness at last rib, and drip loss at 48 h (p < 0.05). The relative abundance of colonic Peptococcus at the genus level was increased and ileal Turicibacter_sp_H121 abundance at the species level was decreased by dietary compound antioxidants. Spearman analysis showed a significant negative correlation between the relative abundance of colonic Peptococcus and plasma MDA concentration and meat drip loss at 48 h. Collectively, dietary supplementation with compound antioxidants of vitamin E, selenium-enrich yeast, and soy isoflavone could improve feed efficiency and antioxidant capacity, and modify the backfat thickness and meat quality through modulation of the gut microbiota community.

Effects of Dietary Vitamin E, Vitamin C, Selenium and Their Combination on Carcass Characteristics, Oxidative Stability and Breast Meat Quality of Broiler Chickens Exposed to Cyclic Heat Stress

Simple Summary

High ambient temperatures present challenging environmental factors in the poultry meat industry, causing heat stress. Heat stress impairs animal health and welfare, growth performance, and productivity, and deteriorates meat quality and its oxidative stability, resulting in economic losses. To mitigate the negative effects of heat stress, several nutritional strategies have been proposed, with vitamin and mineral supplementation being one of the most promising. Several studies reported that the addition of vitamins E and C, as well as selenium, to broiler diets improved the production performance and meat quality of broilers reared under heat stress. Due to the synergistic effects of these antioxidants against the oxidative damage to lipids, combined supplementation could be even more effective in alleviating the symptoms of heat stress on meat quality than supplementation alone, but this has not yet been studied. The results of the present study indicate positive effects of the supplementation with vitamin E on the oxidative stability of breast meat. However, no synergistic effects of the added antioxidants on the measured parameters were observed.

Abstract

The present study was conducted to investigate the effects of dietary supplementation with vitamin E, vitamin C, and Se, alone or in combination, on carcass characteristics, oxidative stability and meat quality parameters of breast meat from broilers exposed to cyclic heat stress (HS), and stored under different conditions. A total of 120 one-day-old male Ross 308 broilers were randomly assigned to six dietary treatments: NRC (minimal nutrition requirements), AVI (commercial nutritional recommendations for Ross 308 broilers), AVI + vitE (as AVI + 200 IU vitamin E/kg feed), AVI + vitC (as AVI + 250 mg vitamin C/kg feed), AVI + Se (as AVI + 0.2 mg Se/kg feed), and AVI + ECSe (as AVI + vitE + vitC + Se). From day 26 onwards, all birds were exposed to a high ambient temperature (31 °C) for 8 h per day. The results showed that dietary vitamin E alone or in combination with vitamin C and Se significantly increased the α-tocopherol content and decreased the malondialdehyde (MDA) content in breast meat. Although no obvious synergistic effects of the added antioxidants were observed, the addition of higher levels of vitamin E, vitamin C and Se to broiler diets had no adverse effects on carcass traits, oxidative stability and meat quality parameters when supplemented either alone or in combination.

Comparing the Influences of Selenium Nanospheres, Sodium Selenite, and Biological Selenium on the Growth Performance, Blood Biochemistry, and Antioxidative Capacity of Growing Turkey Pullets

Supplementation of selenium in poultry feed is required in an optimum dose and form for optimizing the growth performance and health status. Selenium nanospheres are suggested as an efficient and alternative to the conventional organic or inorganic forms. The study evaluated the effects of selenium (Se) nanospheres (SeNPs) as an alternative to organic Se (Sel-Plex^®) or inorganic Se (sodium selenite, Se(IV Se(IV)) on the growth performance, carcass traits, blood biochemistry, and antioxidative capacity in turkey pullets. A total of 160 1-day-old Bronze turkey poults chicks were divided into four groups with 40 pullets each. The birds were fed on four types of diets as fellow: control (basal diet, 0.01 Se mg/kg), SeNPs (0.43 Se mg/kg), organic Se Sel-Plex^® (0.41 Se mg/kg), and inorganic Se(IV) (0.42 Se mg/kg) for 8 weeks. No changes were seen in the body weight gain in growing turkey pullet, but chicks fed with Sel-Plex^® form recorded the lowest feed intake (p < 0.05) compared to other treatments. Dietary SeNPs and Se(IV) selenium sources improved the feed conversion ratio compared to other treatments. All Se forms fed on turkey pullets showed higher carcass percentage weight and liver Se content than the control group. However, the gizzard percentage weight in the SeNPs group was lower than in the other treatments (p < 0.05). Birds fed SeNPs, and Sel-Plex^® forms supplemental diets had a lower cholesterol concentration (p < 0.05) than the control and Se(IV). While high-density lipoprotein (HDL) concentration was increased in SeNPs and Se(IV) groups, and total protein concentration was higher in the Se(IV) group. Furthermore, dietary SeNPs reduced (p < 0.05) the low-density lipoprotein (LDL), total lipids, triglycerides, alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatine, uric acid, urea, and malondialdehyde plasma concentrations and increased the glutathione peroxidase activity (GPx) and total antioxidative capacity (TAC). In conclusion, the results confirmed that feeding turkey pullets on SeNPs form with the 0.4 Se mg/kg of feed enhanced feed efficiency, growth performance, carcass traits, plasma lipids concentration, and antioxidative capacity.

Potential Mechanism and Effects of Different Selenium Sources and Different Effective Microorganism Supplementation Levels on Growth Performance, Meat Quality, and Muscle Fiber Characteristics of Three-Yellow Chickens

A trial was conducted to investigate the effects of different Se sources, including sodium selenite (S-Se) and selenium yeast (Y-Se) and different effective microorganism (EM) addition levels on growth performance, meat quality, and muscle fiber characteristics of three-yellow chickens and its potential mechanism. A total of 400 birds were randomly distributed into 4 groups (S-Se, S-Se + EM, Y-Se, and Y-Se + EM groups) consisting of a 2 × 2 factorial arrangement. The main factors were the source of Se (I_Se = inorganic Se: 0.2 mg/kg S-Se; O_Se = organic Se: 0.2 mg/kg Y-Se) and the level of EM (H_EMB = high EM: 0.5% EM; Z_EMB = low EM: 0% EM). Each treatment had 5 replicates and each replicate consisted of 20 broiler chickens. The trial lasted for 70 days. The results showed that, in breast muscle, the broiler chickens fed O_Se source decreased the pH_24h, drip loss, shear force, perimeter, cross-sectional area, and diameter, but increased the a24h* and density compared with the broiler chickens fed I_Se source (p < 0.05); broiler chickens supplied with H_EMB level decreased the cross-sectional area and diameter, but increased the pH_24h, a24h,* and density compared with the broiler chickens supplied with Z_EMB level (p < 0.05). In thigh muscle, O_Se source and H_EMB level also could improve the meat quality and change muscle fiber characteristics of broiler chickens (p < 0.05). Meat quality was correlated with the muscle fiber characteristics (p < 0.05). O_Se source and H_EMB level could regulate the expression levels of muscle fiber-relative genes in the breast and thigh muscles (p < 0.05). In conclusion, O_Se source and H_EMB level could improve the meat quality of the breast and thigh muscles of three-yellow chickens by changing the muscle fiber characteristics, and they changed the muscle fiber characteristics by regulating the expression levels of muscle fiber-relative genes.

Keratinase improves the growth performance, meat quality and redox status of broiler chickens fed a diet containing feather meal

The objective of this study was to assess the effects of dietary supplementation of keratinase on the production of broilers fed a diet containing feather meal. A total of 162 1-d-old Cobb 500 male broiler (n = 9 cages/diet with 6 chicks/cage) were randomly allocated to 3 dietary treatments. The broilers were fed a corn-soybean-feather meal based diet (BD), or BD supplemented with keratinase at 100,000 or 200,000 U/kg for 6 weeks. Compared to the control, dietary supplementation with 200,000 U/kg keratinase increased (P < 0.05) body weight gain (3.6–4.3%) and reduced feed conversion ratio (2.4–5.6%) during the various experimental periods, and also improved (P < 0.05) apparent total tract digestibility of ash and calcium by 45.0% and 8.8%, respectively. Meanwhile, dietary supplementation of keratinase at 100,000 U/kg reduced (P < 0.05) the drip loss (29.2%), while 200,000 U/kg keratinase supplementation increased (P < 0.05) the pH value (1.6%) at 45 min and decreased (P < 0.05) the lightness (L* value; 13.6%) and drip loss (22.1%) of pectoral muscle. Moreover, dietary supplementation of keratinase at both levels of 100,000 and 200,000 U/kg increased (P < 0.05) Glutathione peroxidase activity (82.5–87.5%) and decreased the Malondialdehyde concentration (14.5–18.3%) in the pectoral muscle. In conclusion, dietary supplementation of keratinase at 200,000 U/kg can improve the performance, meat quality, apparent total tract digestibility of nutrients, and redox status of broiler chickens fed a diet containing feather meal.

Dietary nano-selenium alleviated intestinal damage of juvenile grass carp (Ctenopharyngodon idella) induced by high-fat diet: Insight from intestinal morphology, tight junction, inflammation, anti-oxidization and intestinal microbiota

In recent years, high-fat diet (HFD) has been widely applied in aquaculture, which reduces the intestinal health of cultured fish. The current study evaluated the protective effects of nano-selenium (nano-Se) on intestinal health of juvenile grass carp (Ctenopharyngodon idella) fed with HFD. A total of 135 experimental fish were fed with a regular diet (Con), a HFD (HFD) and a HFD containing nano-Se at 0.6 mg/kg (HSe) for 10 weeks. The results showed that dietary nano-Se significantly improved the survival rate and feed efficiency which were reduced by HFD in juvenile grass carp (P < 0.05). Also, nano-Se (0.6 mg/kg) supplement alleviated intestinal damage caused by the HFD, thus maintaining the integrity of the intestine. Moreover, it significantly up-regulated the expression of genes related to tight junction (ZO-1, c laudin-3 and o ccludin), anti-oxidization (GPx4a andGPx4b), and the protein of ZO-1 in the intestine of juvenile grass carp, which were depressed by the HFD (P < 0.05). Furthermore, nano-Se supplementation significantly suppressed the expressions of genes related to the inflammation, including inflammatory cytokines (IL-8, IL-1β, IFN-γ, TNF-α and IL-6), signaling molecules (TLR4, p38 MAPK and NF-κB p65), and protein expression of NF-κB p65 and TNF-α in the intestine of juvenile grass carp which were induced by the HFD (P < 0.05). Besides, dietary nano-Se normalized the intestinal microbiota imbalance of juvenile grass carp caused by the HFD through increasing the abundance of the beneficial bacteria, e.g., Fusobacteria. Finally, dietary nano-Se increased the production of short chain fatty acids (SCFA) in the intestine, especially for butyric acid and caproic acid, which were negatively related to the increase of intestinal permeability and inflammation. In summary, supply of nano-Se (0.6 mg/kg) in HFD could effectively alleviate intestinal injury of juvenile grass carp by improving intestinal barrier function and reducing intestinal inflammation and oxidative stress. These positive effects may be due to the regulation of nano-Se on intestinal microbiota and the subsequently increased beneficial SCFA levels.

Effects of dietary supplementation with organic selenium-enriched yeast on growth performance, carcass characteristics, and meat quality of finishing lambs

This study was aimed to assess the impact-enriched Saccharomyces cerevisiae with organic selenium addition in finishing lambs on fatty acid composition and physicochemical meat characteristics. Eighteen five-month-old Pelibuey female lambs were fed the same diet for 60 days. Animals were assigned a completely random design of three treatments, control (Se0) without the addition of selenium-yeast or supplemented with 0.35 ppm of selenium-yeast (Se35) and with 0.60 ppm of selenium-yeast (Se60). Lambs were slaughtered at an average weight of 39.5 ± 4.41 kg. Feed intake and meat water holding capacity were decreased (P = 0.001) in Se35 lambs, whereas meat moisture and fat were decreased (P = 0.002) in Se60 lambs. However, meat carbohydrates were increased (P = 0.001) in Se60 lambs. It is concluded that consumption of selenium-yeast in lambs did not alter the productive variables nor the fatty acid composition, though, the fat content is lower, and the carbohydrates are higher in physicochemical meat characteristics.

The Use of Selenium Yeast and Phytobiotic in Improving the Quality of Broiler Chicken Meat

The aim of the present study was to investigate the effect of selenium yeast and phytobiotic on the storage capacity, selected quality parameters of meat and content of selenium in muscles obtained from broilers. In the experiment, 1440 male broiler chickens (Ross 308) were randomly assigned to four research groups: group received no additive (G1), group received a supplement of 0.3 mg Se (as sodium selenite)/kg of feed mixture (G2), group received 0.2 g phytobiotic and 0.3 mg Se as 0.1 g selenium yeast per 1 kg of feed mixture (G3) and group received 0.3 mg Se as 0.1 g selenium yeast per 1 kg of feed mixture (G4). Measurement of pH, determination of water retention capacity, degree of advancement of oxidative changes and selenium content in muscles were performed. Samples of chickens’ breast and thigh muscles were microbiologically analyzed. The additives significantly influenced the level of oxidation in muscles and the incorporation of selenium. The meat of chickens receiving organic selenium was characterized by significantly lower dynamics of oxidative changes. The studies carried out showed that selenium in organic form had better absorption.

Effect of supplementing hydroxy selenomethionine on meat quality of yellow feather broiler

This study was conducted to evaluate the effect of supplementing hydroxy selenomethionine (OH-SeMet) on performance, selenium (Se) deposition in the breast muscle, quality and oxidative stability, and expression of selenoprotein encoding genes of breast meat of the native slow-growing yellow-feathered broiler birds. A total of 375 one-day-old local yellow male birds were randomly assigned into 5 dietary treatments, supplemented with Se 0.0, 0.2, 0.4, 0.6, and 0.8 mg/kg in the form of OH-SeMet. Each treatment consisted of 5 replicates and each replicate had 15 birds, the birds were fed on basal diet containing corn and soybean meal, and the experiment lasted for 63 d. The results showed that dietary Se supplementation linearly increased (P < 0.001) Se contents in both serum and muscle, no significant changes (P > 0.05) were observed on growth performance, yield of breast, meat color, and intramuscular fat deposition of the breast muscle. Dietary Se addition improved water-holding capacity, the pH_24h value, and tenderness of breast muscle, evidenced by a linear decreases of shear force (P < 0.05), accompanied by lower thiobarbituric acid reactive substances and higher glutathione reductase activity. The mRNA abundance of selenoprotein encoding genes also responded to dietary Se levels. It is concluded that, dietary supplementation with OH-SeMet improved muscular Se deposition and meat quality of the native yellow birds, with enhanced antioxidant capability and regulation in selenogenome.

Selenium source and level on performance, selenium retention and biochemical responses of young broiler chicks

Background

Selenium (Se) has been recognized as an essential micronutrient for nearly all forms of life. In recent decades, broiler responses to dietary Se supplemental levels and sources have received considerable attention. On environmental grounds, organic trace mineral utilization in practical broiler feeds has been defended due to its higher bioavailability. In such feeds, trace minerals are provided simultaneously in the same supplement as inorganic salts or organic chelates, a fact commonly ignored in assays conducted to validate organic trace mineral sources. The current assay aimed to investigate growth and biochemical responses, as well as Se retention of growing chicks fed diets supplemented with organic and inorganic Se levels and where the trace minerals (zinc, copper, manganese, and iron) were provided as organic chelates or inorganic salts according to Se source assessed. In so doing, a 2 × 5 factorial arrangement was used to investigate the effects of sodium selenite (SS) and selenium-yeast (SY) supplemented in feeds to provide the levels of 0, 0.08, 0.16, 0.24, and 0.32 mg Se/kg.

Results

Chicks fed selenium-yeast diets had body weight (BW), and average daily gain (ADG) maximized at 0.133 and 0.130 mg Se/kg, respectively. Both Se sources linearly increased (P < 0.05) the glutathione peroxidase (GSH-Px) activity in chick blood but higher values were observed in sodium selenite fed chicks (P < 0.05). Both Se sources influenced thyroid hormone serum concentrations (P < 0.05). Chicks fed SY exhibited greater retention of Se in the feathers (P < 0.05). Relative bioavailability of selenium yeast compared with SS for the Se content in carcass, feathers, total and Se retention were, 126, 116, 125 and 125%, respectively. SY supplementation resulted in lower liver Se concentration as Se supplementation increased (P < 0.05).

Conclusions

Based on performance traits, the supplemental level of organic Se as SY in organic trace minerals supplement to support the maximal growth of broiler chicks is 0.133 mg Se/kg.

The mixed application of organic and inorganic selenium shows better effects on incubation and progeny parameters

This experiment aims to study the effects of dietary selenium (Se) sources on the production performance, reproductive performance, and maternal effect of breeder laying hens. A total of 2,112 Hyline brown breeder laying hens of 42 wk of age were selected and randomly divided into 3 groups, with 8 repeats in each group and 88 chickens per repeat. The sources of dietary Se were sodium selenite (SS, added at 0.3 mg/kg), L-selenomethionine (L-SM, added at 0.2 mg/kg), and combination of SS and L-SM (SS 0.15 mg/kg + L-SM 0.15 mg/kg). The pretest period was 7 d, and the breeding period was 49 d. Compared with 0.3 mg/kg SS, the addition of 0.2 mg/kg L-SM in the diet significantly increased the hatchability (P < 0.05) and the Se content (P < 0.05) in egg yolk and chicken embryo tissues and improved the activity of yolk glutathione peroxidase (GSH-px) effectively (P < 0.05). Treatment with 0.2 mg/kg L-SM also reduced the content of yolk malondialdehyde (P < 0.05) and significantly improved the antioxidant performance of 1-day-old chicks, as manifested by increased activity of antioxidant enzymes (GSH-px, total antioxidant capacity and the ability to inhibit hydroxyl radicals) in serum, pectoral, heart, and liver (P < 0.05). This treatment decreased the malondialdehyde content (P < 0.05) and increased the expression of liver glutathione peroxidase 4 and deiodinase 1 mRNA (P < 0.05). Adding L-SM to the diets of chickens increased the hatchability of breeder eggs as well as the amount of Se deposited and antioxidant enzyme activity in breeder eggs and embryos. Compared with SS, L-SM was more effectively transferred from the mother to the embryo and offspring, showing efficient maternal nutrition. For breeder diets, the combination of organic and inorganic Se (0.15 mg/kg SS + 0.15 mg/kg L-SM) is an effective nutrient supplementation technology program for effectively improving the breeding performance of breeders and the antioxidant performance and health level of offspring chicks.

Selenium-enriched Saccharomyces cerevisiae improves the meat quality of broiler chickens via activation of the glutathione and thioredoxin systems

The aim of this study was to investigate the effects of selenium (Se)-enriched Saccharomyces cerevisiae (SSC) on meat quality and to elucidate the underlying mechanisms in broilers. A total of 200 one-day-old Arbor Acres broiler chickens were randomly allocated to one of four treatments with 5 replications of 10 chickens each. Group 1 served as a control and was fed a basal diet without Se supplementation, while groups 2, 3, and 4 were fed the basal diet supplemented with S. cerevisiae (SC), sodium selenite (SS), and SSC, respectively. Breast muscle samples were collected to evaluate meat quality, selenium concentration, oxidative stability, and the mRNA levels of antioxidant enzyme genes on day 42. As compared with groups 1 and 2, SS and SSC supplementation increased Se concentration, glutathione peroxidase (GPx) and thioredoxin reductase (TR) activities, total antioxidant capacity, and the mRNA levels of GPx-1, GPx-4, TR-1, and TR-3 (P < 0.05) and decreased drip loss and malondialdehyde (MDA) content (P < 0.05). As compared with group 3, SSC supplementation increased pH, lightness, yellowness, Se concentration, GPx and superoxide dismutase activities, and the mRNA levels of GPx-1 and GPx-4 (P < 0.05) but decreased drip loss and MDA content (P < 0.05). Thus, SSC improved meat quality and oxidative stability by activating the glutathione and thioredoxin systems, which should be attributed to the combined roles of Se and SC.

Effect of Different Selenium Sources on Growth Performance, Tissue Selenium Content, Meat Quality, and Selenoprotein Gene Expression in Finishing Pigs

Se-methylselenocysteine (MeSeCys) is a natural organic selenium (Se) supplement. However, its effects on animal nutrition are poorly understood. This study compared the effects of sodium selenite (SeNa), MeSeCys, and selenomethionine (SeMet) on immune function, tissue Se concentration, meat quality, and selenoprotein gene expression in pigs. A total of 72 finishing pigs were divided into four groups, which received a basal diet (BD, 0.1 mg Se/kg) without Se supplementation or one supplemented with SeNa, MeSeCys, or SeMet at a concentration of 0.25 mg Se/kg. Organic Se supplementation significantly increased the immune globulin A (IgA), IgG, and IgM serum levels compared with BD and SeNa groups (P < 0.05). There were no statistically significant differences in growth performance among the four groups. SeMet was more efficient in increasing Se concentrations in the heart, muscle, and liver than MeSeCys and SeNa (P < 0.05), while no statistically significant differences were observed between MeSeCys and SeNa. Se supplementation significantly decreased the pressing muscle loss compared with the BD group (P < 0.05). Meat color and pH were not significantly affected. Se supplement effects on liver selenoprotein gene mRNA level enhancement were ranked as follows: MeSeCys > SeMet > SeNa (P < 0.05). In muscle tissues, only the SELENOW mRNA level was significantly increased by the MeSeCys and SeMet treatment, compared with the SeNa group. In conclusion, SeMet was more efficient in increasing Se concentrations than MeSeCys and SeNa in pigs, while MeSeCys was more efficient in enhancing selenoprotein gene expression than SeMet and SeNa.

Increasing selenium supplementation to a moderately-reduced energy and protein diet improves antioxidant status and meat quality without affecting growth performance in finishing pigs

BACKGROUND

Along with economic development and living standards' improvement, more and more attention has been converted from satisfying meat quantity to pursuing meat quality.

RESEARCH PURPOSE

This study was conducted to evaluate the effects of increasing selenium (Se) supplementation to a moderately-reduced energy and protein diet (MREP) on growth performance, antioxidant status, meat quality in finishing pigs.

BASIC PROCEDURES

A total of 144 "Duroc × Landrace × Yorkshire" pigs with the average body weight of 75 ± 1 kg were randomly allotted to 3 dietary treatments with six replicates per treatment and eight pigs per replicate. The 3 experimental diets were as follows: (1) Normal energy and protein (NEP) +0.2 mg/kg Se diet (14.02 MJ/kg DE, 14% CP and 0.2 mg/kg Se as selenite sodium), (2) MREP +0.2 mg/kg Se diet (13.60 MJ/kg DE, 13% CP and 0.2 mg/kg Se as selenite sodium), and (3) MREP +0.5 mg/kg Se diet (13.60 MJ/kg DE, 13% CP, 0.2 mg/kg Se as selenite sodium, and 0.3 mg/kg Se as Se-enriched yeast). The study lasted for 45 days.

MAIN FINDINGS

The results show that there were no differences for growth performance, antioxidant status and meat quality of finishing pigs between NEP +0.2 mg/kg Se group and MREP +0.2 mg/kg Se group (P＞0.05). However, compared to pigs from MREP +0.2 mg/kg Se group, pigs from MREP +0.5 mg/kg Se group had greater Se concentration, GSH-Px activity and GSH concentration, but lower MDA concentration in serum (P＜0.05). Also, pigs from MREP +0.5 mg/kg Se group had greater Se concentration, T-AOC, and SOD activity, but lower MDA concentration in loin compared with pigs from MREP +0.2 mg/kg Se group (P＜0.05). As for meat quality, pigs from MREP +0.5 mg/kg Se group had greater a* value (relative redness) at 45 min and 24 h in loin compared with pigs from MREP +0.2 mg/kg Se group (P＜0.05). Compared to pigs from MREP +0.2 mg/kg Se group, pigs from MREP +0.5 mg/kg Se group had lower MDA concentration of fresh pork during a simulated retail display at 0, 1, 2, 4, 6 and 7 day (P＜0.05).

PRINCIPAL CONCLUSIONS

In conclusion, increasing selenium supplementation to a moderately-reduced energy and protein diet improved antioxidant status and meat quality without affecting growth performance in finishing pigs. (New Aspects) The present study provided a nutritional strategy for reducing feed costs and improving pork quality without influencing growth performance in finishing pigs.

Effects of Selenium Yeast in Combination with Boron on Muscle Growth and Muscle Quality in Broilers

The effect of selenium yeast in combination with boron on both growth and quality of the muscle in broilers was investigated. A total of 600 one-day-old Arbor Acres broilers were randomly divided into five groups with 120 broilers per group (6 replicates per group). The control group received a basal diet, and experimental groups I-IV received the same basal diet supplemented with 0.3 mg/kg selenium yeast and different doses of boron (0, 5, 10, and 15 mg/kg, respectively). The experiment was conducted for 42 days. Breast and thigh muscles were harvested and muscle quality were examined on day 21 and day 42 of the experiment. Compared to the control group, at 21 days of age, the thigh muscle weight and index were significantly increased in broilers of experimental group II (all P < 0.05); however, the drip loss and shear force of breast and thigh muscle were significantly decreased (P < 0.05). At 42 days of age, the breast muscle weight and index as well as the breast and thigh muscle water holding capability had significantly increased in broilers of experimental group II (all P < 0.05); the breast and thigh muscle drip loss, cooking loss and shear force, and thigh muscle fiber diameter were significantly reduced (all P < 0.05). Breast and thigh muscle fibers were tightly arranged with small cross-sectional areas in broilers of experimental group II. These results suggest that supplementation of 0.3 mg/kg selenium yeast in combination with 5 mg/kg boron in the basal diet can promote muscle growth and improved muscle quality in broilers.