Antioxidant Defence Systems and Oxidative Stress in Poultry Biology: An Update

Evaluating the role of propolis and bee venom on the oxidative stress induced by gamma rays in rats

Honeybee products consist of many substances, which have long been known for their medicinal and health-promoting properties. This study set out to appraise the protective potential of Egyptian propolis (EP) and bee venom (BV) separately or combined against total body irradiation (TBI) induced oxidative injury in rats. Besides, we assessed the bioactive components in EP and BV using HPLC and UPLC/ ESI-MS analysis in the positive ion mode. The animals were subjected to a source of gamma ionizing radiation at a dose of 6 Gy. Propolis and BV were administered independently and in combination before 14 days of γ-irradiation. Liver and kidney functions were estimated besides, DNA damage index (8- OHdG) by ELISA. Antioxidants, including glutathione (GSH), catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) were detected. Gene expression technique investigated for BAX, BCL2, and in plasma also miR125b expression in serum of rats. Besides, the histopathological for the brain, liver, kidney, and heart were investigated. In addition, lipid peroxidation was investigated in plasma and in the previous organs. The present results provide opportunities to advance the use of bee products as promising medicinal sources.

H2O2-induced oxidative stress impairs meat quality by inducing apoptosis and autophagy via ROS/NF-κB signaling pathway in broiler thigh muscle

Oxidative stress is the downstream of various adverse stresses which impairs meat quality of broiler chickens. Yet, the specific molecular mechanisms of oxidative stress in meat quality of broiler thigh muscle remains unclear. This study investigated the effects and mechanisms of H₂O₂-induced oxidative stress on meat quality of broiler thigh muscle, with particular emphasis on apoptosis and autophagy and the ROS/NF-κB signaling pathway. The results showed that 10%H₂O₂-treated broilers exhibited significantly higher drip loss and shear force and lower pH_24h and muscle weight. Moreover, the ROS formation, the contents of oxidation products, the expressions of caspases (3, 6, 8, 9), Beclin1, and LC3-II/LC3-I were significantly increased, whereas the levels of antioxidation products and the expression of phosphorylation of NF-κBp65 were significantly decreased. These findings from the present study indicating that H₂O₂-induced oxidative stress significantly impaired the meat quality by inducing apoptosis and abnormal autophagy via ROS/NF-κB signaling pathway in the broiler thigh muscle.

Effects of β-alanine and L-histidine supplementation on carnosine contents in and quality and secondary structure of proteins in slow-growing Korat chicken meat

Carnosine enrichment of slow-growing Korat chicken (KRC) meat helps differentiate KRC from mainstream chicken. We aimed to investigate the effects of β-alanine and L-histidine supplementation on the carnosine synthesis in and quality and secondary structure of proteins in slow-growing KRC meat. Four hundred 21-day-old female KRC were used, and a completely randomized design was applied. The chickens were divided into 4 experimental groups: basal diet (A), basal diet supplemented with 1.0% β-alanine (B), 0.5% L-histidine (C), and 1.0% β-alanine combined with 0.5% L-histidine (D). Each group consisted of 5 replicates (20 chickens per replicate). On d 70, 2 chickens per replicate were slaughtered, and the levels of carnosine, anserine, and thiobarbituric acid reactive substances were analyzed. Biochemical changes were monitored using synchrotron radiation-based Fourier transform infrared microspectroscopy; 5 chickens per replicate were slaughtered, and the meat quality was analyzed. Statistical analysis was performed using ANOVA and principal component analysis (PCA). Group D chickens exhibited the highest carnosine meat content, followed by those in groups B and C. However, amino acid supplementation did not affect anserine content and growth performance. Higher carnosine levels correlated with increasing pH_{45 min} and decreasing drip loss, cooking loss, shear force, and lipid oxidation. PCA revealed that supplementation with only β-alanine or L-histidine was related to increased content of β-sheets, β-turns, and aliphatic bending groups and decreased content of α-helix groups. This study is the first to report such findings in slow-growing chicken. Our findings suggest that KRC can synthesize the highest carnosine levels after both β-alanine and L-histidine supplementation. Higher carnosine contents do not adversely affect meat quality, improve meat texture, and alter the secondary structures of proteins. The molecular mechanism underlying carnosine synthesis in chickens needs further study to better understand and reveal markers that facilitate the development of nutrient selection programs.

An investigation of different intracellular parameters for Inborn Errors of Metabolism: Cellular stress, antioxidant response and autophagy

Oxidative stress is associated with various disease pathologies including Inborn Errors of Metabolism (IEMs), among the most important causes of childhood morbidity and mortality. At least as much as oxidative stress in cells, reductive stress poses a danger to the disruption of cell homeostasis. p62/SQSTM1, protects cells from stress by activation of Nrf2/Keap1 and autophagy pathways. In this study, we tested the role of cellular stress, mitochondrial dysfunction and autophagy via Nrf2/Keap1/p62 pathway in the pathophysiology of three main groups of IEMs. Our results showed that antioxidant and oxidant capacity alone would not be sufficient to reflect the true clinical picture of these diseases. ATP, ROS and mitochondrial membrane potantial (MMP) measurements demonstrated increased cellular stress and bioenergetic imbalance in methylmalonic acidemia (MMA), indicating mild mitochondrial dysfunction. In isovaleric acidemia (IVA), no major change was detected in ATP, ROS and MMP values. Propionic acidemia (PA), mitochondrial diseases (MIT) and mucopolysaccharidosis IV (MPS IV) might point out mitohormesis to cope with chronic reductive stress. Induction of Nrf2/Keap1/p62 pathway and increased expression of HMOX1 were detected in all IEMs. LC3B-II and p62 expression results indicated an impaired autophagic flux in MIT and MPS IV and an induction of autophagic flux in MMA, PA and IVA, but also partial expression of Beclin1, enables autophagy activation, was detected in all IEMs. We conclude that individual diagnosis and treatments are of great importance in IEMs. In addition, we assume that the application of therapeutic antioxidant or preventive treatments without determining the cellular stress status in IEMs may disrupt the sensitive oxidant-antioxidant balance in the cell, leading to the potential to further disrupt the clinical picture, especially in patients with reductive stress. To the best of our knowledge, this is the first study to simultaneously relate IEMs with cellular stress, mitochondrial dysfunction, and autophagy.

Salt-contaminated water inducing pulmonary hypertension and kidney damage by increasing Ang II concentration in broilers

NaCl is the main component of freshwater salinization. High NaCl concentration in drinking water can cause pulmonary hypertension syndrome (PHS) and kidney damage in broilers. To explore the effect of NaCl in drinking water on broilers' kidneys, this study divided 80 chickens into four groups. With the control group fed with pure water, broiler chickens were fed with fresh water (FW, NaCl 1 g/L), low salt-contaminated water (L-SCW, NaCl 2.5 g/L), and high salt-contaminated water (H-SCW, NaCl 5 g/L). The results show that ascites heart index (AHI) and hematocrit (HCT) of broilers increase in L-SCW and H-SCW, the serum blood urea nitrogen and creatinine of broilers increase significantly, the kidney index increases, the kidney sections show vacuolar degeneration and fibrotic degeneration, and the TUNEL results show that the kidneys possess obvious apoptosis. In addition, the detection of RAAS-related genes (AGT gene in the liver, REN in the kidney, ACE in the lung) demonstrates that after using salt-contaminated water, the transcription levels of AGT, REN, and ACE rise significantly, and the concentration of angiotensin II (Ang II) also increases significantly. In order to verify the effect of Ang II on broiler kidneys, this research used exogenous Ang II to treat chicken embryonic kidney (CEK) cells. The results show that the cell activity of CEK decreased with the increase of the concentration of exogenous Ang II. Meanwhile, the flow cytometry assay shows that Ang II could promote the apoptosis of CEK cells. These results indicate that the salt-contaminated water can aggravate PHS and cause kidney damage. The mechanism may be related to the increase of Ang II.

Effect of chlorogenic acid on follicular development, hormonal status and biomarkers of oxidative stress in rats with polycystic ovary syndrome

Polycystic ovarian syndrome (PCOS) is a complex endocrine and metabolic disorder. Chlorogenic acid (CGA) bears antioxidant properties with protective effects on different tissues. This study was conducted to evaluate the effect of CGA on follicular development, hormonal status and biomarkers of oxidative stress in a rat model of PCOS. In this experimental study, 18 rats were divided into three equal groups including: control, non-treated PCOS [(estradiol valerate (EV): 40.00 mg kg^-1 intramuscularly)], and PCOS-CGA (EV: 40.00 mg kg^-1 intramuscularly and CGA: 100 mg kg^-1 intraperitoneally once a week for eight consecutive weeks). At the end of treatment period, all rats were anesthetized. Then 5.00 mL blood samples of rats in the three groups were taken and prepared for hormonal analyses and their ovaries were isolated and dissected mechanically free of fat and mesentery. The ovaries underwent the following analyses: Morphological study with Hematoxylin and Eosin staining and biochemical study using the malondialdehyde (MDA) level and total antioxidant activity. Data were analyzed using one-way ANOVA and post hoc Tukey's test. The serum level of luteinizing hormone, estrogen, testosterone, antioxidant capacity, glutathione and the number of cystic follicles in the PCOS group treated with 100 mg kg^-1 Chlorogenic acid compared to the non-treated PCOS group were significantly decreased, however, the serum level of follicle stimulating hormone, progesterone, MDA and the number of secondary, graafian follicles and corpus luteum were significantly increased. Chlorogenic acid could be effective in ameliorating follicular development as well as hormonal and biochemical disorders in rats with PCOS.

Physical Exercise as a Modulator of Vascular Pathology and Thrombin Generation to Improve Outcomes After Traumatic Brain Injury

Disruption of the blood-brain barrier and occurrence of coagulopathy after traumatic brain injury (TBI) have important implications for multiple secondary injury processes. Given the extent of post-traumatic changes in neuronal function, significant alterations in some targets, such thrombin (a protease that plays a physiological role in maintaining blood coagulation), play an important role in TBI-induced pathophysiology. Despite the magnitude of thrombin in synaptic plasticity being concentration-dependent, the mechanisms underlying TBI have not been fully elucidated. The understanding of this post-injury neurovascular dysregulation is essential to establish scientific-based rehabilitative strategies. One of these strategies may be supporting physical exercise, considering its relevance in reducing damage after a TBI. However, there are caveats to consider when interpreting the effect of physical exercise on neurovascular dysregulation after TBI. To complete this picture, this review will describe how the interactions established between blood-borne factors (such as thrombin) and physical exercise alter the TBI pathophysiology.

Sex-Specific Association of Serum Anti-Oxidative Capacity and Leukocyte Telomere Length

Telomeres are a crucial factor in the preservation of genomic integrity, and an elevated risk for diseases such as cancer and cardiovascular events is related to shortened telomeres. However, telomere deterioration could be caused by factors such as chronic oxidative stress and inflammation, which are promoted by an imbalance among reactive oxygen species (ROS) and antioxidants. In this cross-sectional study, we investigated the relationship between telomeres and oxidative stress. The serum leucocyte telomer length (LTL), serum total antioxidant capacity (TAC) and the total serum lipid panel of 180 healthy athletic volunteers (90 males, 90 females) were measured Additionally, a questionnaire about sports behaviour and the type of training was completed. We observed a positive significant relation between serum LTL and TAC in the male group (cc = 3.4/p = 0.001) but not in females. There was no statistically significant correlation between age and physical activity and LTL in both groups. This is the first cross sectional study demonstrating an association between total serum TAC and LTL in healthy males, but interestingly, not in the females. Nevertheless, these results should be interpreted as preliminary, and further studies in independent cohorts are needed to investigate the sex-specific effects of oxidative stress on telomere length and telomerase activity.

Metabolomic analysis indicates that higher drip loss may be related to the production of methylglyoxal as a by-product of glycolysis

The aim of the present study was to assess applicability of metabolomics analysis of exudate from chicken breast muscle to explanation of differences in drip loss. The research was carried out on the skinless breast fillets sourced from 60 broiler carcasses (7-wk-old male Ross broilers). In the meat samples the pH value, color parameters, drip loss, chemical composition, and sensory quality were evaluated. After measuring, the samples were divided into 2 groups taking into consideration the volume of drip loss (low ≤2% and high >2% drip loss). The muscle juice samples were collected during 24 h muscle storage and metabolomic analysis was performed. The results showed that chickens with higher drip loss were characterized by heavier carcasses. The meat with higher drip loss proved to be more acid, lighter, less red, and more yellow with higher level of glucose as well as glycolytic potential. That meat was also characterized by lower cooking loss, protein content and worse overall sensory quality as well as oxidation of lipids. The metabolomics analyses have shown that in the group with higher drip loss from muscle tissue the increase of metabolism of energy transformations taking place in muscle tissue after slaughter was observed and that differences between groups are related to 11 metabolic pathways, mainly carbohydrate metabolism (glycolysis, gluconeogenesis, pentose phosphate pathway) adenine and adenosine salvage, adenosine nucleotides degradation, arsenate detoxification, methylglyoxal degradation. Finally, the results indicate that in the group with higher drip loss and with deeper glycolysis, more methylglyoxal (as a by-product of carbohydrate metabolism) is produced which may lead to changes of muscle proteins properties and contribute to an increase in drip loss.

Taurine as a Natural Antioxidant: From Direct Antioxidant Effects to Protective Action in Various Toxicological Models

Natural antioxidants have received tremendous attention over the last 3 decades. At the same time, the attitude to free radicals is slowly changing, and their signalling role in adaptation to stress has recently received a lot of attention. Among many different antioxidants in the body, taurine (Tau), a sulphur-containing non-proteinogenic β-amino acid, is shown to have a special place as an important natural modulator of the antioxidant defence networks. Indeed, Tau is synthesised in most mammals and birds, and the Tau requirement is met by both synthesis and food/feed supply. From the analysis of recent data, it could be concluded that the direct antioxidant effect of Tau due to scavenging free radicals is limited and could be expected only in a few mammalian/avian tissues (e.g., heart and eye) with comparatively high (>15-20 mM) Tau concentrations. The stabilising effects of Tau on mitochondria, a prime site of free radical formation, are characterised and deserve more attention. Tau deficiency has been shown to compromise the electron transport chain in mitochondria and significantly increase free radical production. It seems likely that by maintaining the optimal Tau status of mitochondria, it is possible to control free radical production. Tau's antioxidant protective action is of great importance in various stress conditions in human life, and is related to commercial animal and poultry production. In various in vitro and in vivo toxicological models, Tau showed AO protective effects. The membrane-stabilizing effects, inhibiting effects on ROS-producing enzymes, as well as the indirect AO effects of Tau via redox balance maintenance associated with the modulation of various transcription factors (e.g., Nrf2 and NF-κB) and vitagenes could also contribute to its protective action in stress conditions, and thus deserve more attention.

Immune response and antioxidant status of broilers as influenced by oxidized vegetable oil and pomegranate peel

The experiment was designed as a 3 × 3 × 2 factorial arrangement of treatments, including (i) pomegranate peel (zero, 4%, and 8 percent), (ii) oxidized soybean oil (zero, 2%, and 4 percent), and (iii) alpha-tocopherol (zero and 200 mg/kg). Supplementation of 8% pomegranate peel in diets significantly decreased the growth performance of broiler chickens. The supplementation of 4% oxidized oil in diets significantly reduced body weight gain and Feed intake whole experimental period (p < 0.05). The results showed that supplementation of 4% pomegranate peel in the diet was associated with low aspartate transaminase (AST), alanine transaminase, and malondialdehyde (MDA). However, 4% pomegranate peel increased the total antioxidant capacity (TAC) and superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities. The supplemental 4% oxidized oil increased the serum AST, alanine aminotransferase (ALT), and MDA concentrations. TAC, SOD, and Catalase (CAT) activities were affected by 4% oxidized oil and alpha-tocopherol. The use of oxidized oil and vitamin E decreased MDA concentration. The serum glucose and globulin concentrations were significantly lower in the 8% pomegranate peel. The results showed that supplementation with 4% pomegranate peel in diets reduced serum low-density lipoprotein (LDL). The inclusion of 4% oxidized oil in diets reduced serum glucose and increased the blood lipid concentration such as triglyceride, cholesterol and LDL. Vitamin E supplementation reduced the serum cholesterol and LDL concentrations. The use of 8% pomegranate peel reduced red blood cell (RBC), hemoglobin, and packed cell value (PCV). The results indicated that supplementation with 8% pomegranate peel and 4% oxidized oil in diets decreased the immunoglobulin concentration in broilers. In addition, it was found that the inclusion of 4% pomegranate peel in diets resulted in higher IgG, IgM and total immunoglobulin. Pomegranate peel supplementation significantly decreased meat MDA concentration. Supplementation of 4% oxidized oil increased MDA of meat (p < 0.05). Vitamin E supplementation (200 mg/kg) significantly decreased MDA of meat (p < 0.05). Consequently, the results of this experiment showed that supplementation with 4% pomegranate peel had beneficial effects on broiler chickens. It was also found that feeding 2% oxidized oil in diets had no adverse effect on broilers.

Low levels of organic compound trace elements improve the eggshell quality, antioxidant capacity, immune function, and mineral deposition of aged laying hens

In the egg production industry, trace elements are required as additional dietary supplements to play vital roles in performance and egg quality. Compared to inorganic microelements (ITs), appropriate dose of organic trace microelements (OTs) are environmentally friendly and sufficient to satisfy the needs of hens. In order to evaluate the extent to which low-dose OTs replace whole ITs, the effects of organic copper, zinc, manganese, and iron compound on the performance, eggshell quality, antioxidant capacity, immune function, and mineral deposition of old laying hens were investigated. A total of 1 080 57-week-old Jing Hong laying hens were assigned to five groups with six replicates of 36 layers each for an 8-week experimental period. The birds were fed either a basal diet (control treatment (CT)) or the basal diet supplemented with commercial levels of inorganic trace elements (IT 100%) or the equivalent organic trace elements at 20%, 30%, and 50% of the inorganic elements (OT 20%, OT 30%, and OT 50%, respectively). Results showed that compared with those in the CT treatment, feeding hens with inorganic or organic microelement diet had significant effects on the eggshell quality, antioxidant capacity, immune function, and mineral deposition of old laying hens (P < 0.05). The eggshell strength and ratio between OT 30%, OT 50%, and IT 100% were similar at weeks 4 and 8, and the eggshell thickness of these groups was also similar at weeks 6 and 8. At week 8, the eggshell colour in OT 50% was darker than that in IT 100%. The mineral content in the eggshells of OT 50% and IT 100% significantly increased (P < 0.001), with no significant difference in effective thickness, mammillary thickness, and mammillary knob width between groups. There were no differences in the malondialdehyde content, total antioxidant capacity, and total superoxide dismutase activity in serum between OT 30%, OT 50%, and IT100%. While the catalase activities, the interleukin-1β, interleukin-10, immunoglobulin G, and immunoglobulin M concentrations in serum were not significantly different between OT 50% and IT 100%. The mineral contents in the faeces of the organic groups were considerably reduced compared with those in IT 100% (P < 0.001). In conclusion, dietary supplementation with 30-50% organic compound microelements has the potential to replace 100% inorganic microelements in the hen industry for improving eggshell quality, mineral deposition in the eggshell, antioxidant capacity, and immune function, and reducing emissions to the environment without negative effects on laying performance.

Prophylactic effects of dietary ascorbic acid on oxidative stress indices, physiological and behavioural responses of domestic pigeons exposed to road transport stress

Transport disturbs birds' welfare and health status which lead to oxidative stress and dietary ascorbic acid mitigates the adverse effects of transport stress. The present study was aimed to evaluate the impacts of ascorbic acid administration on oxidative stress indices, cortisol, H/L ratio, tonic immobility reaction and rectal temperature of pigeons exposed to road transport. A total of 80 clinically healthy pigeons were selected and randomly divided to eight equal groups as follow: (1) Ctrl- : fed by basal diet and no subjected to transport stress; (2) Ctrl+: fed by the basal diet and subjected to transport stress; (3, 4) 1DBS10 and 1DBS16: received ascorbic acid from 1 day before transport stress at doses of 10 g/100 L and 16 g/100 L of drinking water, respectively; (5, 6) 3DBS10 and 3DBS16: treated with ascorbic acid from 3 consecutive days before transport stress at doses of 10 g/100 L and 16 g/100 L, respectively and (7, 8) 7DBS10 and 7DBS16: received ascorbic acid from 7 consecutive days before the transport at doses 10 g/100 L and 16 g/100 L, respectively. Birds were transported for 3 h over a distance of about 200 km. The total antioxidant capacity, malondialdehyde and cortisol were measured before transport and at 6, 24 and 72 h post-transportation. The rectal temperature and tunic immobility reactions were recorded. Dietary ascorbic acid led to a decrease in tonic immobility response, hetrophil to lymphocyte ratio, circulating cortisol and total antioxidant capacity, and an increase in circulating malondialdehyde in pigeons exposed to transport stress compare to Ctrl+ group. In conclusion, ascorbic acid administration at dose 16 g/100 L of drinking water from 3 and 7 days before exposure to stress helps attenuate undesirable effects of oxidative stress in pigeons.

Longitudinal evidence for immunosenescence and inflammaging in free-living great tits

The first-line effector mechanisms of immune defence, including inflammation and oxidative burst, contribute significantly to host-pathogen resistance. Whether these immune responses undergo age-related changes in birds remains unknown. Here, we tracked selected inflammatory parameters in 54 free-living great tits (Parus major) of known age, captured repeatedly over three consecutive years, with the aims to investigate long-term repeatability and age-dependent changes in cellular oxidative burst responsiveness upon in vitro stimulation with bacterial lipopolysaccharide (LPS), and to identify its relationships with leukotriene B4 (LTB4) levels and haematological traits. In addition, we linked these immunological traits to selected physiological markers (antioxidants and oxidative stress markers). LTB4 levels increased with age and we have shown a similar non-significant tendency also for absolute granulocyte counts, indicating propagating chronic inflammation over the bird's lifetime, consistent with the inflammaging hypothesis. In contrast, cellular oxidative burst followed a quadratic trend of dependency on age with a peak in midlife individuals, in line with the immunosenescence hypothesis. Interestingly, LTB4 levels were positively associated with general oxidative damage, but negatively with antioxidant glutathione peroxidase activity, indicating links to redox balance. This longitudinal study demonstrates the contrasting patterns of age-related changes in background and acute markers of pro-inflammatory immunity contributing to immunosenescence in birds and thus provides basis for interpretation of the tested inflammatory markers in cross-cohort datasets.

Protective Effects of Sesamin on Cytoxan-Induced Spermatogenesis Dysfunction by Regulating RNF8-ubH2A/ubH2B Pathways in Male Mice

Most of the clinically infertile patients show spermatogenesis dysfunction. Cyclophosphamide, as an anticancer drug, can induce spermatogenesis dysfunction. Sesamin is the main bioactive component of natural lignans in sesame. It is abundant in sesame oil and has strong biological activities such as antioxidant, antibacterial, and hypoglycemic properties. By establishing the model of spermatogenic dysfunction induced by cyclophosphamide in male mice and then feeding sesamin (50, 100, and 200 mg/kg) for 2 weeks, we proved that sesamin can improve the reproductive organ damage induced by cyclophosphamide and increase the number and activity of sperms. Sesamin can resist cyclophosphamide-induced sperm nuclear maturity and DNA damage by increasing the expression levels of histones H2A and H2B in the testis. In addition, sesamin can improve the ubiquitination of histones regulated by RNF8 to protect the testis. In conclusion, these results suggest that sesamin can improve spermatogenic dysfunction induced by cyclophosphamide, which may be mediated by ubiquitination of histones.

Effects of the Probiotic Activity of Bacillus subtilis DSM 29784 in Cultures and Feeding Stuff

The European Union banned the usage of antibiotic growth promoters in animal production. The probiotic microorganism of the genus Bacillus appeared to be an attractive candidate to replace antibiotics. The Bacillus subtilis DSM 29784 is one of these strains. To date, the probiotic effect has not been completely understood, but it is supposed that the effect depends on metabolites of the microorganism. Imaging high-performance thin-layer chromatography (HPTLC) is a powerful tool to visualize differences in the metabolite profile of bacteria with high genetic similarity to allow a better understanding of the probiotic effect. In comparison to other bacteria, especially these bacterial cells were more robust to harsh cultivation conditions and produced a higher level of antioxidants or bioactive substances such as surfactin. HPTLC enabled the comparison of pure cell cultures to the spore cultivation in the feed, and the results explain and support the probiotic effect.

Yarrowia lipolytica, health benefits for animals

The yeast Yarrowia lipolytica has been industrially adopted for docosahexaenoic acid and eicosapentaenoic acid production under good manufacturing practices over 2 decades. In recent years, it has claimed attention for novel biotechnological applications, such as a functional feed additive for animals. Studies have demonstrated that this yeast is safe and has probiotic and nutritional properties for mammals, birds, fish, crustaceans, and molluscs. Animals fed Y. lipolytica enhanced productive and immune parameters, as well as modulated microbiome, fatty acid composition, and biochemical profiles. Additionally, some Y. lipolytica-derived compounds have improved productive performance, immune status, and disease resistance in animals. Therefore, the aim of this review is to identify and discuss research advances on the potential use of this yeast for animals of economic interest. Challenges, opportunities, and trends were identified and envisioned in the near future for this industrially produced yeast. KEY POINTS: • Yarrowia lipolytica has probiotic and nutritional effects in animals. • Lipase2, EPA, and β-glucan from Y. lipolytica have health benefits for animals. • Y. lipolytica is envisioned in terrestrial and aquatic animal production systems.

Plant Feed Additives as Natural Alternatives to the Use of Synthetic Antioxidant Vitamins on Livestock Mammals' Performances, Health, and Oxidative Status: A Review of the Literature in the Last 20 Years

In the last two decades, the interest in natural plant feed additives (PFA) as alternatives to synthetic vitamins in livestock nutrition has increased. After a systematic review, a total of 19 peer-reviewed papers published between 2000 and 2020 were retained to evaluate the antioxidant effects of PFA compared to synthetic antioxidant vitamins (mainly vitamin E; VitE) in livestock nutrition. These studies demonstrated that PFAs could be as efficient as VitE in counteracting oxidative stress in pigs, rabbits, and ruminants. However, PFAs only positively affected animals’ growth performance and feed efficiency in some monogastric studies. The PFA can affect antioxidant enzyme activity in a dose- and method of administration-dependent manner. The antioxidant capacity of both PFA and VitE were depressed in cows fed with diets rich in polyunsaturated fatty acids. Variability among studies could be related to species differences. Despite the interest of the feed industry sector in PFA, there are still very few studies evaluating their antioxidant effect in species other than poultry.

Effect of agarwood leaf extract on production performance of broilers experiencing heat stress

Background and Aim:

The open house cage is mainly influenced by the environmental heat from the sun and the heat released by the chicken. Heat stress can affect physiological conditions so that it has an impact on decreasing productivity. This study aims to determine the effect of agarwood leaf extract in feed on the physiological condition and production performance of broilers experiencing heat stress and to generate prediction equations for the optimal level of the extract in feed.

Materials and Methods:

A total of 200 22-day-old broilers (Cobb 500™) underwent four treatments with five replications each, namely, feed without agarwood leaf extract (control) (T0), and feed with 250 (T1), 300 (T2), and 350 mg of agarwood leaf extract/kg body weight (T3). The parameters observed include physiological condition (heart rate, respiratory frequency, and body temperature) as well as production performance (feed consumption, body weight gain [BWG], and feed conversion).

Results:

The administration of agarwood leaf extract significantly (p<0.05) decreased heart rate and respiratory frequency. However, there was no significant difference (p>0.05) in body temperature, glucose levels, hemoglobin and erythrocyte concentrations, as well as production performance which include weight gain, feed consumption, and feed conversion ratio. Meanwhile, broilers treated with agarwood leaf extract had a significantly lower heart rate and respiratory frequency (p<0.05) compared to the control. However, broilers given agarwood leaf extract showed better body weight, consumption, and ration conversion compared to the control.

Conclusion:

Agarwood leaf extract in feed reduces heart rate and respiratory frequency but has no significant effect on body temperature and hematological parameters (glucose levels, hemoglobin, and erythrocyte concentrations) as well as production performance (feed consumption, weight gain, and feed conversion). These results indicate that the administration of 350 mg/kg body weight agarwood leaf extract is most effective to reduce feed consumption and increase BWG.

Energy expenditure across immune challenge severities in a lizard: consequences for innate immunity, locomotor performance and oxidative status

Reptiles, like other vertebrates, rely on immunity to defend themselves from infection. The energetic cost of an immune response is liable to scale with infection severity, prompting constraints on other self-maintenance traits if immune prioritization exceeds energy budget. In this study, adult male side-blotched lizards (Uta stansburiana) were injected with saline (control) or high (20 µg g-1 body mass) or low (10 µg g-1 body mass) concentrations of lipopolysaccharide (LPS) to simulate bacterial infections of discrete severities. The costs and consequences of the immune response were assessed through comparisons of change in resting metabolic rate (RMR), energy metabolites (glucose, glycerol, triglycerides), innate immunity (bactericidal ability), sprint speed and oxidative status (antioxidant capacity, reactive oxygen metabolites). High-LPS lizards had the lowest glucose levels and greatest sprint reductions, while their RMR and bactericidal ability were similar to those of control lizards. Low-LPS lizards had elevated RMR and bactericidal ability, but glucose levels and sprint speed changes between those of high-LPS and control lizards. Levels of glycerol, triglycerides, reactive oxygen metabolites and antioxidant capacity did not differ by treatment. Taken together, energy expenditure for the immune response varies in a non-linear fashion with challenge severity, posing consequences for performance and self-maintenance processes in a reptile.

Onion leaf and synthetic additives in broiler diet: impact on splenic cytokines, serum immunoglobulins, cecal bacterial population, and muscle antioxidant status

BACKGROUND

The disadvantages associated with the use of synthetic additives in animal production could threaten human and animal health, and the safety of animal-derived foods. This study assessed the growth performance, blood chemistry, immune indices, selected caeca bacterial population, muscle antioxidant enzyme activities, and meat quality in broiler chickens fed diet supplemented with antibiotic (70% oxytetracycline +30% neomycin), tert-butylhydroxytoluene or onion leaf powder (OLP). One day old Ross 308 chicks (n = 240) were assigned randomly to either D-1, control diet (CD) without additives; D-2, CD + 0.3 g kg^-1 antibiotic +0.15 g kg^-1 tert-butylhydroxytoluene; D-3, CD + 2.5 g kg^-1 OLP; or D-4, CD + 5 g kg^-1 OLP for 42 days.

RESULTS

The D-2 and D-4 diets improved (P < 0.05) bodyweight gain and feed efficiency in broilers. Platelet and cecal Lactobacillus spp. counts were higher (P < 0.05) whereas muscle cholesterol was lower (P < 0.05) in the OLP-supplemented birds. Supplemented birds had higher (P < 0.01) splenic interleukin-10 and lower (P < 0.01) splenic tumor necrosis factor-α, immunoglobulin A, cecal E. coli and C. perfringens counts compared with the D-1 birds. The D-4 birds had the least (P < 0.05) splenic interleukin-1β. Dietary supplements increased (P < 0.05) catalase, glutathione peroxidase, and total antioxidant capacity, and lowered (P < 0.05) drip loss, malondialdehyde and carbonyl content in breast meat.

CONCLUSION

Dietary supplementation of 5 g kg^-1 OLP exerted antimicrobial, immunomodulatory, and antioxidant effects that were comparable to those of antibiotics and tert-butylhydroxytoluene in broiler chickens. © 2021 Society of Chemical Industry.

Nutritional and physiological responses of broiler chicken to the dietary supplementation of Moringa oleifera aqueous leaf extract and ascorbic acid in tropics

This study was intended to determine the comparative effects of Moringa oleifera aqueous leaf extract (MOALE) and ascorbic acid supplementation in the drinking water on growth performance, haemato-biochemical profile, antioxidant status and immune response of broiler chickens under tropical climate. All 135-day-old broiler chicks were divided into 3 different treatment groups. T0 served as control, T1 were fed basal ration with MOALE (90 ml/L drinking water), and T2 offered basal ration with ascorbic acid (15 mg/L drinking water) for 35-day experiment. All the standard managemental practices were followed during the experimental period. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity of MOALE was calculated with reference to different ascorbic acid concentration as standard. The antioxidant activity percentage of MOALE (90 µl) was 93.89%, and ascorbic acid (15 µg) was 98.76%, respectively, which was nearer to cent percent. Therefore, 90 ml MOALE and 15 mg ascorbic acid per litre drinking water, respectively, were used for supplementation in broiler chicken. The growth performance and feed efficiency were better in MOALE group followed by ascorbic acid supplemented birds without affecting the metabolism of nutrients. However, 10.71% better FCR was noted in MOALE supplemented group followed by ascorbic acid group (6.28%) in comparison with control. Most of the haemato-biochemical profiles were unaffected by the treatment except creatinine, while antioxidant profile was improved in the treatment group. Immunity status of broiler chicken against NDV was enhanced in both treatment groups; however, maximum profit is obtained in MOALE group followed by ascorbic acid supplemented birds.

Honeybee and Plant Products as Natural Antimicrobials in Enhancement of Poultry Health and Production

The quality and safety attributes of poultry products have attracted increasing widespread attention and interest from scholarly groups and the general population. As natural and safe alternatives to synthetic and artificial chemical drugs (e.g., antibiotics), botanical products are recently being used in poultry farms more than 60% of the time for producing organic products. Medicinal plants, and honeybee products, are natural substances, and they were added to poultry diets in a small amount (between 1% and 3%) as a source of nutrition and to provide health benefits for poultry. In addition, they have several biological functions in the poultry body and may help to enhance their welfare. These supplements can increase the bodyweight of broilers and the egg production of laying hens by approximately 7% and 10% and enhance meat and egg quality by more than 25%. Moreover, they can improve rooster semen quality by an average of 20%. Previous research on the main biological activities performed by biotics has shown that most research only concentrated on the notion of using botanical products as growth promoters, anti-inflammatory, and antibacterial agents. In the current review, the critical effects and functions of bee products and botanicals are explored as natural and safe alternative feed additives in poultry production, such as antioxidants, sexual-stimulants, immuno-stimulants, and for producing healthy products.

Effects of Dietary Ferulic Acid on the Intestinal Microbiota and the Associated Changes on the Growth Performance, Serum Cytokine Profile, and Intestinal Morphology in Ducks

The present study investigated the effects of ferulic acid (FA) on the growth performance, serum cytokine profile, intestinal morphology, and intestinal microbiota in ducks at the growing stage. 300 female Linwu ducks at 28 days of age with similar body weights were randomly divided into five groups. Each group contained six replicates of 10 birds. The dietary treatments were corn-soybean-based diet supplemented with FA at the concentrations of 0 (control), 100, 200, 400, and 800 mg/kg diet. The results demonstrated that dietary FA at the levels of 200, 400, and 800 mg/kg increased the average daily gain (P = 0.01), 400 and 800 mg/kg FA increased the final body weight (P = 0.02), 100, 200, and 800 mg/kg FA increased the serum glutathione (P = 0.01), and 100, 400, and 800 mg/kg FA increased the glutathione peroxidase activities in birds (P < 0.01). Additionally, 200, 400, and 800 mg/kg dietary FA lowered the serum levels of interleukin-2 (P = 0.02) and interleukin-6 (P = 0.04). Moreover, the morphometric study of the intestines indicated that 400 mg/kg FA decreased the crypt depth in jejunum (P = 0.01) and caecum (P = 0.04), and increased the ratio of villus height to crypt depth in jejunum (P = 0.02). Significant linear and/or quadratic relationships were found between FA concentration and the measured parameters. 16S rRNA sequencing revealed that dietary FA increased the populations of genera Faecalibacterium, Paludicola, RF39, and Faecalicoccus in the cecum (P < 0.05), whereas decreased the populations of Anaerofilum and UCG-002 (P < 0.05). The Spearman correlation analysis indicated that phylum Proteobacteria were negatively, but order Oscillospirales, and family Ruminococcaceae were positively related to the parameters of the growth performance. Phylum Bacteroidetes, class Negativicutes and family Rikenellaceae were negatively associated with the parameters of the antioxidative capability. And phylum Cyanobacteria, Elusimicrobia, and Bacteroidetes, class Bacilli, family Rikenellaceae, and genus Prevotella were positively associated with the parameters of the immunological capability. Thus, it was concluded that the supplementations of 400 mg/kg FA in diet was able to improve the growth performance, antioxidative and immunological capabilities, intestinal morphology, and modulated the gut microbial construction of Linwu ducks at the growing stage.

The Effect of Green Tea (Camellia sinensis) Leaf Powder on Growth Performance, Selected Hematological Indices, Carcass Characteristics and Meat Quality Parameters of Jumbo Quail

Green tea leaves contain a wide range of active bio-compounds that are essential for sustainable quail intensification; however, its feed value is not known for the Jumbo quail. Therefore, this study evaluated the effect of different levels of green tea leaf powder (GTLP) on physiological and meat quality parameters of the Jumbo quail. One-week-old chicks (n = 350; 56.1 ± 2.12 g live-weight) were evenly distributed to 35 replicate pens and reared on five experimental diets formulated as follows: a standard grower diet with zinc-bacitracin (PosCon), a standard grower diet without zinc-bacitracin (NegCon), and NegCon diet treated with 10 (GT10), 25 (GT25) and 50 g/kg (GT50) of GTLP. Weight gain linearly decreased in week 2 but increased in week 4, whereas feed conversion efficiency linearly declined in weeks 2 and 3 as GTLP levels increased. Overall feed intake, carcass yield, and caecum and colon weights showed a linear increase with GTLP levels. Hematological parameters fell within the normal ranges reported for healthy quail. The GT10 group showed larger liver weights than the PosCon and NegCon groups. It was concluded that dietary inclusion of GTLP enhances overall feed intake and carcass performance but not feed efficiency, hematological and meat quality parameters of Jumbo quail.

In-feed organic and inorganic manganese supplementation on broiler performance and physiological responses

Objective

A trial was conducted to investigate the effects of supplemental levels of Mn provided by organic and inorganic trace mineral supplements on growth, tissue mineralization, mineral balance, and antioxidant status of growing broiler chicks.

Methods

A total of 500 male chicks (8-d-old) were used in 10-day feeding trial, with 10 treatments and 10 replicates of 5 chicks per treatment. A 2×5 factorial design was used where supplemental Mn levels (0, 25, 50, 75, and 100 mg Mn/kg diet) were provided as MnSO₄·H₂O or MnPro. When Mn was supplied as MnPro, supplements of zinc, copper, iron, and selenium were supplied as organic minerals, whereas in MnSO₄·H₂O supplemented diets, inorganic salts were used as sources of other trace minerals. Performance data were fitted to a linear-broken line regression model to estimate the optimal supplemental Mn levels.

Results

Manganese supplementation improved body weight, average daily gain (ADG) and feed conversion ratio (FCR) compared with chicks fed diets not supplemented with Mn. Manganese in liver, breast muscle, and tibia were greatest at 50, 75, and 100 mg supplemental Mn/kg diet, respectively. Higher activities of glutathione peroxidase and superoxide dismutase (total-SOD) were found in both liver and breast muscle of chicks fed diets supplemented with inorganic minerals. In chicks fed MnSO₄·H₂O, ADG, FCR, Mn balance, and concentration in liver were optimized at 59.8, 74.3, 20.6, and 43.1 mg supplemental Mn/kg diet, respectively. In MnPro fed chicks, ADG, FCR, Mn balance, and concentration in liver and breast were optimized at 20.6, 38.0, 16.6, 33.5, and 62.3 mg supplemental Mn/kg, respectively.

Conclusion

Lower levels of organic Mn were required by growing chicks for performance optimization compared to inorganic Mn. Based on the FCR, the ideal supplemental levels of organic and inorganic Mn in chick feeds were 38.0 and 74.3 mg Mn/kg diet, respectively.

Role of the glutathione redox system in the susceptibility of pheasants (Phasianus colchicus) to ochratoxin A

The purpose of the present study was to investigate the effects of different dietary concentrations of ochratoxin A (OTA) on the growth, feed intake, mortality, blood plasma protein content and some parameters of lipid peroxidation and the glutathione redox system of pheasant chicks in a three-week long trial. A total of 320 seven-day-old female pheasants were randomly assigned to four treatment groups (n = 40 in each), fed with a diet artificially contaminated with OTA [control (<0.02 mg/kg), 0.88 mg/kg, 1.14 mg/kg and 1.51 mg/kg] for 21 days (up to 28 days of age). The pheasant chicks were sacrificed at early (12, 24 and 72 h) and late (7, 14 and 21 days) stages of mycotoxin exposure to check the effect of OTA. Minimal feed refusal was found in the medium- and high-dose toxin groups (-9.8 and -7.9%, respectively), and body weight gain was nearly the same in all groups. The glutathione redox system was activated mainly in the liver, confirmed by significantly increased reduced glutathione content and glutathione peroxidase activity during the late phase of mycotoxin exposure and at a high-dose treatment. The results suggest that pheasants have low susceptibility to OTA, and activation of the glutathione redox system has importance in this tolerance.

Pomegranate peel as a phytogenic in broiler chickens: Influence upon antioxidant, lipogenesis and hypotensive response

The aim of this study was to evaluate antioxidant, antihyperlipidemic and hypotensive properties of pomegranate peel (PP) on antioxidant status, fat deposition, lipid peroxidation and pulmonary hypertensive response in broiler chickens. A total of 375 one‐day‐old male broilers (Cobb 500) were randomly assigned to five treatments included dietary PP levels of 0, 2.5, 5.0, 7.5 and 10 g/kg. Supplementation of PP at 7.5 and 10 g/kg resulted in significant upregulation of hepatic catalase (p < 0.004) and superoxide dismutase1 (SOD1; p < 0.05), which reflected in decreased concentration of circulatory malondialdehyde (MDA). Dietary inclusion of PP at 7.5 and 1.0 g/kg significantly decreased serum concentrations of triglycerides (p < 0.004) and cholesterol (p < 0.006) with concomitant decrease in abdominal fat deposition (p < 0.05). The antihyperlipidemic effect of PP was mediated through down‐regulation of peroxisome proliferator activated receptor alpha (PPARα). Hypotensive effect of PP was also observed at 7.5 and 10 g/kg as reduced heart weight and the right‐to‐total ventricular weight ratio (RV/TV) and decreased mortality from pulmonary hypertension. The hypotensive property of PP was associated with increased concentration of serum nitric oxide. In conclusion, this study revealed antioxidative, antihyperlipidemic and hypotensive effects of PP at 7.5 and 10 g/kg in broiler chickens exposed to hypobaric hypoxia. Health‐beneficial effects of PP suggest this product as a promising multi‐functional phytogenic feed additive for broiler chickens.

In this study, evaluate antioxidant, antihyperlipidemic, and hypotensive properties of pomegranate peel (PP) on antioxidant status, fat deposition, lipid peroxidation, and pulmonary hypertensive response in broiler chickens. Supplementation of PP at 7.5 and 10 g/kg resulted in significant up‐regulation of hepatic catalase, superoxide dismutase1 and peroxisome proliferator activated receptor alpha (PPARα), which reflected in decreased concentration of circulatory malondialdehyde (MDA).

Effect on physiological and production parameters upon supplementation of fermented yeast culture to Nicobari chickens during and post summer

Nicobari is an indigenous bird reared for meat and eggs. This study evaluated the effect of heat stress on plasma levels of leptin, growth hormone and their receptors, liver AMP kinase, plasma cholesterol and lipid peroxide (MDA). The laying period coincided with the post summer period. The birds were equally divided into three groups, control group was offered ad libitum feed and treatment groups were supplemented with fermented yeast culture at 700 mg (T1) and 1.4 g/kg (T2) of feed/day. The levels of plasma Leptin and GH hormones were higher (p < 0.05) in the control group when compared to the treatment groups. The expression of the hormone receptors was higher in the brain, and MMP3 gene expression in the magnum was lower in the treatment group. Plasma cholesterol, MDA and AMP kinase were significantly higher (p < 0.05) in the control group. Fermented yeast culture supplementation decreased feed intake and increased egg production parameters, which indicates a greater efficiency of supplementation. Supplementation reduced the severity of necrosis of villi in the jejunum when compared to control. In conclusion, higher ambient temperature during summer had negative effect on production parameters through modulation of physiological parameters which could be ameliorated by supplementation of FYC.

Oral Delivery of Bacillus subtilis Expressing Chicken NK-2 Peptide Protects Against Eimeria acervulina Infection in Broiler Chickens

Chicken NK-lysin peptide 2 (cNK-2) is a natural lytic peptide with direct cytotoxicity against many apicomplexan parasites including Eimeria. Developing an effective oral delivery strategy to express cNK-2 in the intestine, where Eimeria parasites interact with the host's gut epithelial cells, may effectively reduce the fecundity of parasites and minimize intestinal damage. Furthermore, cNK-2 modulates gut immune responses to decrease local inflammation elicited by Eimeria infection in the intestine. Therefore, we developed a stable strain of Bacillus subtilis (B. subtilis) that carries cNK-2 to the gut to determine its effectiveness in ameliorating the negative impacts of coccidiosis and to replace the use of antibiotics in controlling coccidiosis in commercial broiler chicken production. Chickens were randomly allocated into eight treatment groups: two control groups (NC: E. acervulina infected non-B. subtilis control; CON: non-infected control); three B. subtilis-empty vector (EV) groups (EV6: 10⁶ cfu/day/bird; EV8: 10⁸ cfu/day/bird; EV10: 10¹⁰ cfu/day/bird), and three B. subtilis-cNK-2 groups (NK6: 10⁶ cfu/day/bird; NK8: 10⁸ cfu/day/bird; NK10: 10¹⁰ cfu/day/bird). All chickens, except those in the CON group, were challenged with 5,000 freshly sporulated E. acervulina oocysts through oral gavage on day 15. Chickens were given an oral dose of B. subtilis on days 14, 15, and 16. Body weight, weight gains, and fecal oocyst shedding were measured. To investigate the efficacy of oral B. subtilis-cNK-2 against coccidiosis, gene expression of gut health-related biomarkers was measured using RT-PCR. Markers included SOD1, CAT, and HMOX1 for oxidative stress in the spleen and intestinal mucosa, OCLN, ZO-1, and JAM2 for tight junction proteins, and MUC2 for mucin gene expression in the gut. The results showed that oral treatment of young chickens with B. subtilis-cNK-2 improved growth performance, enhanced gut integrity, and reduced fecal oocyst shedding. Altogether, these results confirm B. subtilis-cNK-2 treatment as a promising and effective alternative strategy to replace antibiotics against coccidiosis based on its ability to reduce parasite survival, to reduce coccidiosis-induced body weight loss, and to decrease gut damage based on the enhanced expression of proteins associated with gut integrity and intestinal health.

Nanoselenium and Selenium Yeast Have Minimal Differences on Egg Production and Se Deposition in Laying Hens

The objective of this study was to compare the effects of nanoselenium (NS) and selenium yeast (SY) on the performance, egg selenium (Se) concentration, and anti-oxidative capacity of hens. A total of 216 Brown Hy-line hens (29-week old) were randomly allocated into three treatments (6 replicate/treatment, 12 hens/replicate). The pre-trial period lasted 7 days, and the experimental period lasted 35 days. Dietary treatments included corn-soybean meal basal diet (containing 0.16 μg Se/g, as control group), and basal diet supplemented with 0.3 mg Se/kg diet (Se was from NS or SY), called as SY group or NS group, respectively. At the end of the experiment, one hen per replicate from each treatment was slaughtered. Liver, spleen, and kidney tissues were sampled for the determination of Se concentrations. The results showed that NS or SY supplement significantly improved feed conversion ratio (P < 0.05), soft broken egg rate (P < 0.05), and the serum T-AOC value (P < 0.05) when compared with control group. Remarkably, the deposition of Se increased significantly (P < 0.05) and equivalently in egg, liver, and kidney of hens supplemented with both NS and SY. Interestingly, SY supplement also enhanced the serum CAT and SOD activities (P < 0.05), NS but not SY significantly reduced serum MDA (P < 0.05), whereas RT-PCR results did not show significant differences in the mRNA levels of antioxidant genes among three groups (P > 0.05). Taken together, dietary supplemented with SY or NS improved the Se deposition in eggs, liver and kidney of laying hens, increased antioxidant activity, and NS supplement had greater Se deposition in the kidney tissue than SY supplement. SY or NS supplement could be considered to be applied for Se-enriched egg production.

Plant Feed Additives as Natural Alternatives to the Use of Synthetic Antioxidant Vitamins in Livestock Animal Products Yield, Quality, and Oxidative Status: A Review

The interest for safe and natural foods of animal origin is currently increasing the use of plant feed additives (PFA) as antioxidants in animal nutrition. However, studies with livestock animals dealing with PFA as antioxidants are scarce. The aim of the present review was to evaluate the antioxidant impact of PFA compared with synthetic vitamins on animal food product yield and quality. For this purpose, peer-reviewed studies published between 2000 and 2020 were collected. Most papers were carried out on ruminants (n = 13), but PFA were also tested in swine (n = 6) and rabbits (n = 2). The inclusion of PFA in the diets of pigs, rabbits, and ruminants improved the products’ quality (including organoleptic characteristics and fatty acids profile), oxidative stability, and shelf life, with some impacts also on their yields. The effects of PFA are diverse but often comparable to those of the synthetic antioxidant vitamin E, suggesting their potential as an alternative to this vitamin within the diet.

In Ovo Injection of GABA Can Help Body Weight Gain at Hatch, Increase Chick Weight to Egg Weight Ratio, and Improve Broiler Heat Resistance

Simple Summary

Heat stress is a vital issue that causes severe losses to the poultry industry. A partly developed thermoregulatory mechanism during the embryonic phase is emphasized to manipulate embryos for achieving thermotolerance during rearing. The present study was conducted firstly to standardize the dosage for an in ovo manipulation, and the selective dose was used to evaluate its effects on early-age heat-stressed (HS) broilers. HS induces cholesterol while an antioxidant acts as a first line of defense under stress. However, 5% GABA supplementation had a higher hatchling weight and chick weight to egg weight ratio (CWEWR). We selected a 10% GABA dosage for HS studies due to its higher antioxidants and lower cholesterol values in hatchlings. In ovo, 10% GABA supplementation significantly increased total antioxidant capacity and reduced malondialdehyde levels, hepatic mRNA levels of HSP70, FAS, and L-FABP in broilers when subjected to HS (38 ± 1 °C; 3 h) at ten days of age. This indicates that an in ovo GABA injection improves CWEWR and antioxidant status at hatch, and creates thermotolerance by increasing antioxidant production and downregulating the expression of HSP70 and fatty acid metabolism genes in HS chicks.

Abstract

The aim of this study was to explore the outcomes of an in ovo GABA injection in broilers challenged with HS. In Experiment 1, 210 Arbor Acres eggs were allocated to five treatments: no-injection, and in ovo injection of 0.6 mL of 0%, 5%, 10%, or 20% of GABA. Hatchling weight and CWEWR were significantly increased in the 5% GABA group. In ovo, injection of 10% GABA solution caused a significant decrease in plasma cholesterol and increased plasma total antioxidant capacity of hatchlings. Experiment 2 was conducted with 126 fertile Arbor Acres eggs distributed into one of two groups. At 17.5 days of incubation, one received no injection, and the other was fed 0.6 mL of 10% GABA. On day 10, one subgroup (4 replicates * 3 birds) from each treatment was submitted to HS (38 ± 1 °C for 3 h) while the other was kept at a thermoneutral temperature (29 ± 1 °C). An in ovo injection of GABA significantly increased total antioxidant capacity, but reduced malondialdehyde levels, hepatic mRNA levels of HSP70, FAS, and L-FABP with HS. In conclusion, an in ovo GABA injection improves CWEWR and antioxidant status at hatch, and enhances antioxidant status while downregulating the expression of HSP70 and fatty acid metabolism-related genes in young chicks under HS.

Spirulina platensis Inclusion Reverses Circulating Pro-inflammatory (Chemo)cytokine Profiles in Broilers Fed Low-Protein Diets

Proteins are considered the most expensive nutrients in commercial modern broiler production, and their dietary inclusion at low levels is pivotal to minimize feed costs and reduce nitrogen waste. The quest for an environmentally friendly source of proteins that favor the formulation of low protein diets without compromising broiler health, welfare, and growth performance has become a hotspot in nutrition research. Due to its high protein content, the naturally growing Spirulina microalgae is considered a promising nutrient source. The purpose of the present study was, therefore, to determine the effects of Spirulina supplementation on liver bacterial translocation, hematological profile, and circulating inflammatory and redox markers in broilers fed a low-protein diet. One-day-old Ross 708 male broilers (n = 180) were randomly assigned into one of three experimental treatments: standard diet as a control, low protein diet, and low protein diet supplemented with 100 g/kg of Spirulina. Target molecular markers were measured in the peripheral blood circulation using real-time quantitative PCR. Reducing dietary proteins increased bacterial translocation and systemic inflammation as indicated by proportions of basophils among blood leukocytes. The expression levels of circulating pro-inflammatory cytokines [interleukin (IL)-3, IL-6, IL-4, IL-18, and tumor necrosis factor-α], chemokines (CCL-20), and NOD-like receptor family pyrin domain containing 3 inflammasome were significantly upregulated in birds fed the low protein diet compared with the control. The inclusion of Spirulina reversed these effects, which indicates that Spirulina reduces systemic inflammation- and bacterial translocation-induced by a low protein diet and could be a promising alternative protein source in poultry diets.

Ameliorative Effects of the Sesquiterpenoid Valerenic Acid on Oxidative Stress Induced in HepG2 Cells after Exposure to the Fungicide Benomyl

Valerenic acid (VA) is a sesquiterpenoid and a phytoconstituent of the plant valerian used for sleeping disorders and anxiety. The frequency of using herbal components as therapeutic nutritional agents has increased lately. Their ability to improve redox homeostasis makes them a valuable approach against harmful xenobiotics. The purpose of this study was to evaluate the putative beneficial role of VA against the redox-perturbating role of the fungicide benomyl in HepG2 human liver cells in terms of oxidative stress in the cellular environment and in endoplasmic reticulum (ER). Benomyl increased cell total oxidant status and reactive oxygen species production and decreased total antioxidant status. The expression of genes coding for antioxidant molecules, namely, heme oxygenase-1, alpha glutathione s-transferase, NF-ĸB, and liver fatty acid binding protein, were decreased due to benomyl. VA ameliorated these effects. Benomyl also increased ER-stress-related molecules such as endoplasmic reticulum to nucleus signaling 1 protein, glucose-regulated protein 78, and caspase-12 levels, and VA acted also as a preventive agent. These results indicate that VA exerts ameliorative effects after benomyl-induced oxidative stress. VA, a widely used nutritional supplement, is a compound with potent antioxidant properties, which are valuable for the protection of cells against xenobiotic-induced oxidative damage.

Impact of juçara (Euterpe edulis) fruit waste extracts on the quality of conventional and antibiotic-free broiler meat

Juçara (Euterpe edulis) is a native Brazilian palm tree from the Atlantic Forest, whose fruit-processing waste can present high concentration of antioxidant compounds. This research was assessed to determine the antioxidant potential of juçara waste extracts aiming to reduce the lipid and protein oxidation processes on conventional and antibiotic-free broiler meat throughout 9 d during refrigerated storage. The juçara waste extracts were obtained by microwave-assisted extraction. Two different extracts were tested based on the optimum point obtained when checking total phenolic (TPC) contents (Extract P) and antioxidant activity (Extract A) based on a previous study. The treatments using conventional and antibiotic-free broiler meat included: chicken patties without antioxidant addition (AFBNC and CBNC), with synthetic antioxidant (BHT) (AFBPC and CBPC), with Extract P (AFBEP and CBEP) and with Extract A (AFBEA and CBEA), totaling 8 treatments. Antioxidant activity of extracts along with TPC, flavonoid, anthocyanin, and tannin contents of extracts and patties were assessed. Proximate composition, fatty acid profile, lipid and protein oxidation process, and instrumental color were analyzed in patty treatments. Although both extracts had similar content of TPC and tannin, extract A presented the highest anthocyanin, while extract P exhibited the highest flavonoid. While extract A exhibited the highest antioxidant activity, extract P was highly influential in the stability of lipid oxidative degradation in both types of broiler meat (AFBEP and CBEP), and as successful as BHT (AFBPC and CBPC). In addition, extract P was also able to stabilize protein oxidation in conventional broiler meat (CBEP) from the third day, until the end of the storage period. Therefore, the fruit waste extract P of juçara can be a promising source of natural antioxidants to prevent the oxidative process in conventional and antibiotic-free broiler meat.

Methylglyoxal-Dependent Glycative Stress Is Prevented by the Natural Antioxidant Oleuropein in Human Dental Pulp Stem Cells through Nrf2/Glo1 Pathway

Methylglyoxal (MG) is a potent precursor of glycative stress (abnormal accumulation of advanced glycation end products, AGEs), a relevant condition underpinning the etiology of several diseases, including those of the oral cave. At present, synthetic agents able to trap MG are known; however, they have never been approved for clinical use because of their severe side effects. Hence, the search of bioactive natural scavengers remains a sector of strong research interest. Here, we investigated whether and how oleuropein (OP), the major bioactive component of olive leaf, was able to prevent MG-dependent glycative stress in human dental pulp stem cells (DPSCs). The cells were exposed to OP at 50 µM for 24 h prior to the administration of MG at 300 µM for additional 24 h. We found that OP prevented MG-induced glycative stress and DPSCs impairment by restoring the activity of Glyoxalase 1 (Glo1), the major detoxifying enzyme of MG, in a mechanism involving the redox-sensitive transcription factor Nrf2. Our results suggest that OP holds great promise for the development of preventive strategies for MG-derived AGEs-associated oral diseases and open new paths in research concerning additional studies on the protective potential of this secoiridoid.

Stress and immunity in poultry: light management and nanotechnology as effective immune enhancers to fight stress

The poultry industry plays a significant role in boosting the economy of several countries, particularly developing countries, and acts as a good, cheap, and affordable source of animal protein. A stress-free environment is the main target in poultry production. There are several stressors, such as cold stress, heat stress, high stocking density, and diseases that can affect birds and cause several deleterious changes. Stress reduces feed intake and growth, as well as impairs immune response and function, resulting in high disease susceptibility. These effects are correlated with higher corticosteroid levels that modulate several immune pathways such as cytokine-cytokine receptor interaction and Toll-like receptor signaling along with induction of excessive production of reactive oxygen species (ROS) and thus oxidative stress. Several approaches have been considered to boost bird immunity to overcome stress-associated effects. Of these, dietary supplementation of certain nutrients and management modifications, such as light management, are commonly considered. Dietary supplementations improve bird immunity by improving the development of lymphoid tissues and triggering beneficial immune modulators and responses. Since nano-minerals have higher bioavailability compared to inorganic or organic forms, they are highly recommended to be included in the bird's diet during stress. Additionally, light management is considered a cheap and safe approach to control stress. Changing light from continuous to intermittent and using monochromatic light instead of the normal light improve bird performance and health. Such changes in light management are associated with a reduction of ROS production and increased antioxidant production. In this review, we discuss the impact of stress on the immune system of birds and the transcriptome of oxidative stress and immune-related genes, in addition, how nano-minerals supplementations and light system modulate or mitigate stress-associated effects.

Influence of Anacardium occidentale leaf supplementation in broiler chicken diet on performance, caecal microbiota, blood chemistry, immune status, carcass, and meat quality

1. This study investigated the growth performance, caecal microbiota, blood chemistry, splenic cytokines, serum immunoglobulins, carcase, meat quality and oxidative status of broiler chickens fed diets supplemented with Anacardium occidentale leaf powder (AOLP) in comparison with antibiotic and synthetic antioxidant.2. Three hundred and twenty, one-day old Arbor Acre broiler chicks were randomly allotted into four treatment groups consisting of eight pen replicates with 10 birds per pen. The treatment groups were T0, basal diet only; T1, basal diet + 0.4 g/kg oxytetracycline + 0.12 g/kg butylated hydroxyanisole (BHA); T2, basal diet + 2 g/kg AOLP and T3, basal diet + 4 g/kg AOLP. The birds were fed for 42 d when performance was assessed, and then euthanised.3. During 0-42 d, feed conversion ratio was higher (P = 0.033) in T0 birds compared with birds fed other diets. Diet did not affect carcase traits, organ weights, serum biochemical indices, and meat composition, pH, cook loss or meat colour. Supplemented birds had higher erythrocyte (P = 0.042) and haemoglobin (P = 0.025), and lower leukocytes (P = 0.012) compared with the T0 birds.4. Diet T3 upregulated (P = 0.020) splenic interleukin-10 compared with other diets. The T0 birds had higher (P < 0.05) interleukin-6 and serum IgG and IgM compared with the supplemented birds. Caecal E. coli and Salmonella spp. counts were higher (P < 0.05) in T0 birds than in the supplemented groups. Lactobacillus spp. counts were higher (P = 0.001) in T3 birds than in those fed other diets. Breast and thigh meat from the T0 birds had higher (P < 0.05) TBARS value, and carbonyl content compared to the supplemented birds. The T0 breast meat had higher drip loss (P = 0.001) than meat from the supplemented birds.5. The results suggested that AOLP exhibited antimicrobial and antioxidant properties that were comparable to the responses to oxytetracycline and BHA (T1) in broiler diets. Nonetheless, the efficacy of AOLP needs to be verified under disease challenge or compromised health condition.

Heat Stress in Broiler Chickens and the Effect of Dietary Polyphenols, with Special Reference to Willow (Salix spp.) Bark Supplements-A Review

Over the last decade, there has been a growing interest in the use of a wide range of phytoadditives to counteract the harmful effects of heat stress in poultry. Willow (Salix spp.) is a tree with a long history. Among various forms, willow bark is an important natural source of salicin, β-O-glucoside of saligenin, but also of polyphenols (flavonoids and condensed tannins) with antioxidant, antimicrobial, and anti-inflammatory activity. In light of this, the current review presents some literature data aiming to: (1) describe the relationship between heat stress and oxidative stress in broilers, (2) present or summarize literature data on the chemical composition of Salix species, (3) summarize the mechanisms of action of willow bark in heat-stressed broilers, and (4) present different biological effects of the extract of Salix species in different experimental models.

Algae-based antioxidant containing selenium yeast (Economase®) enhanced the growth performance, oxidative stability, and meat quality of broiler chickens

Objective

An experiment was conducted to determine the effect of algae-based antioxidant containing Se yeast (EconomasE^®) on the growth performance, visceral organ weight, meat quality, and oxidative stability of broiler chickens.

Methods

Nine hundred sixty, day-old male broiler chickens (Cobb, 43.97±0.55 g) were divided into three dietary treatments and allocated into 12 deep litter pens in a completely randomized design giving 4 replicate cages for each treatment. Three dietary treatments were: i) control (CON, basal diet with sufficient nutrient), ii) vitamin E (VitE, basal diet supplemented with 100 IU VitE), and iii) Algae-based antioxidant containing Se yeast (EcoE, basal diet supplemented with 0.2% algae-based antioxidant containing Se yeast: EconomasE^®). Maize soybean meal based basal diets were formulated to meet or exceed the nutrition requirement for broiler chickens. Chickens were fed ad-libitum experimental diets during the 42 days experiment period. On days 21 and 42, body weight and feed intake were measured to calculate the feed conversion ratio of the chickens. Intestine and visceral organs were measured together with meat quality and oxidative stability on days 14 and 42.

Results

Chickens fed with EcoE showed improved (p<0.05) growth performance, meat quality, and higher (p<0.05) oxidative stability compared to the chicken fed on CON. Moreover, broiler chickens fed with EcoE showed similar (p<0.05) growth performance with better (p<0.05) meat quality and higher oxidative stability compared to the broiler chickens fed VitE (p<0.05).

Conclusion

The algae-based antioxidant containing Se yeast can be supplemented into commercial broiler diets as a substitution of VitE while maintaining growth performance with enhancing meat quality and oxidative stability of the broiler chickens.

Diabetic retinopathy, oxidative stress, and sirtuins: an in depth look in enzymatic patterns and new therapeutic horizons

Diabetic retinopathy (DR) is one of the leading causes of blindness in the world. DR represents the most common microvascular complication of diabetes, and its incidence is constantly rising. The complex interactions between inflammation, oxidative stress, and the production of free oxygen radicals caused by prolonged exposure to hyperglycemia determine the development of DR. Sirtuins (SIRTs) are a recently discovered class of 7 histone deacetylases involved in cellular senescence, regulation of cell cycle, metabolic pathways, and DNA repair. SIRTs participate in the progress of several pathologies such as cancer, neurodegeneration, and metabolic diseases. In DR sirtuins 1,3,5, and 6 play an important role as they regulate the activation of the inflammatory response, insulin sensibility, and both glycolysis and gluconeogenesis. A wide spectrum of direct and indirect activators of SIRTs pathways (e.g., antagomiR, resveratrol, or glycyrrhizin) is currently being developed to treat the inflammatory cascade occurring in DR. We focus on the main metabolic and inflammatory pathways involving SIRTs and DR, as well as recent evidence on SIRTs activators that may be employed as novel therapeutic approaches to DR.

Dietary Pomegranate By-Product Alleviated the Oxidative Stress Induced by Dexamethasone in Laying Hens in the Pre-Peak Period

Simple Summary

The present work was designed to maximize an agro-industrial by-products’ benefits in an environmentally safe manner. This study explores the antioxidative effects of pomegranate peels as dietary additives on the performance of laying hens in the pre-peak period under oxidative stress induced by dexamethasone. Pomegranate peel powder was included at 2% and 4% in the diets of laying hens exposed to oxidative stress induced by dexamethasone compared with negative and positive control groups for 12 weeks. Based on the obtained results, the current study recommends the possibility of using dietary pomegranate peels up to 4% not only for alleviating the adverse effects of oxidative stress in the pre-peak laying period but also as a sustainable and economical approach for agricultural development.

Abstract

This experiment was conducted to assess the inclusion of the by-products of pomegranate peels to ameliorate the harmful impacts of oxidative stress in the pre-peak period of laying hens. For this, 120 local Egyptian strain hens (Inshas hens) aged 24 weeks old were used in four treatments. Pomegranate peel powder was included at 2% and 4% in the diets of laying hens subjected to oxidative injuries induced by dexamethasone compared with negative and positive control groups for 12 weeks. The addition of pomegranate peel powder (PPP) reduced the adverse effects of oxidative stress induced by dexamethasone on body weight (p = 0.006) and egg production (p = 0.010) comparing to the positive control. Additionally, pomegranate peel powder had a significant positive lowering effect on plasma cholesterol (p < 0.001) and triglyceride contents (p = 0.005) compared to control groups. The lipid peroxidation indicators (MDA) were reduced, but the antioxidative enzymes (SOD, CAT, and GPx) and total antioxidant blood capacity were improved with PPP. Based on the obtained data, the present research recommends using dietary PPP up to 4% to mitigate adverse oxidative stress effects in the pre-peak laying period and as a sustainable and economical approach for agricultural development.

Dietary supplementation of dried plum: a novel strategy to mitigate heat stress in broiler chickens

Background

Heat stress is a significant problem in the poultry industry, causing a severe economic loss due to its detrimental effects on chickens’ health and performance. Dried plum (DP) is a good source of minerals, vitamins, antioxidants, and phenolic compounds. Studies have suggested that DP has several health benefits, such as maintaining the body’s redox system, immune status, and calcium hemostasis. Based on the health benefits of DP, we hypothesized that the dietary supplementation of DP would alleviate the detrimental effects of heat stress on broiler chickens.

Results

To test the hypothesis, day-old broiler chicks (n = 72) were randomly allocated to three treatment groups (n = 24/group): no heat stress (NHS), heat stress (HS), and heat stress with dried plum (HS + DP), and reared under standard conditions. The inclusion of 2.5% DP in the feed of the HS + DP group was made during the treatment period, while birds in other groups were provided with a standard finisher diet. After 21 days, birds in the HS and HS + DP groups were exposed to cyclic heat stress conditions (33 °C for 8 h during daytime) for 3 weeks, while those in the NHS group were reared under normal conditions (22–24 °C). Weekly body weight and feed intake were recorded to calculate the average daily gain (ADG), average daily feed intake (ADFI), and feed conversion ratio (FCR). Heat stress significantly decreased the final body weight, ADG, ADFI, and increased FCR compared to the NHS group, whereas dietary supplementation of DP significantly improved these growth performance parameters compared to the HS group. Furthermore, supplementation of DP significantly increased the expression of heat shock protein-related genes (HSF1, HSF3, HSP70, and HSP90), antioxidant-related genes (SOD1, SOD2, GPX1, GPX3, PRDX1, and TXN), tight junction-related genes (CLDN1, and OCLN), and immune-related genes (IL4, MUC2) in the ileum as compared to the HS group. The microbiota analysis showed significant enrichment of Bacillales, Christensenellaceae, Bacillaceae, Peptostreptococcaceae, and Anaerotruncus in heat-stressed birds supplemented with DP as compared to the HS group. Further, DP supplementation also significantly increased the concentration of acetate, propionate, and total VFA in the cecal digesta of the HS + DP group as compared to the HS group.

Conclusion

These findings suggest that DP supplementation effectively improved the growth performances and gut health parameters in the heat-stressed birds. Thus, dried plum can be a potential feed supplement to mitigate heat stress in broiler chickens.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40104-021-00571-5.

Dietary Oxidative Distress: A Review of Nutritional Challenges as Models for Poultry, Swine and Fish

The redox system is essential for maintaining cellular homeostasis. When redox homeostasis is disrupted through an increase of reactive oxygen species or a decrease of antioxidants, oxidative distress occurs resulting in multiple tissue and systemic responses and damage. Poultry, swine and fish, raised in commercial conditions, are exposed to different stressors that can affect their productivity. Some dietary stressors can generate oxidative distress and alter the health status and subsequent productive performance of commercial farm animals. For several years, researchers used different dietary stressors to describe the multiple and detrimental effects of oxidative distress in animals. Some of these dietary challenge models, including oxidized fats and oils, exposure to excess heavy metals, soybean meal, protein or amino acids, and feeding diets contaminated with mycotoxins are discussed in this review. A better understanding of the oxidative distress mechanisms associated with dietary stressors allows for improved understanding and evaluation of feed additives as mitigators of oxidative distress.

Nutritional manipulation to combat heat stress in poultry - A comprehensive review

Global warming and climate change adversely affect livestock and poultry production sectors under tropical and subtropical conditions. Heat stress is amongst the most significant stressors influencing poultry productivity in hot climate regions, causing substantial economic losses in poultry industry. These economic losses are speculated to increase in the coming years with the rise of global temperature. Moreover, modern poultry strains are more susceptible to high ambient temperature. Heat stress has negative effects on physiological response, growth performance and laying performance, which appeared in the form of reducing feed consumption, body weight gain, egg production, feed efficiency, meat quality, egg quality and immune response. Numerous practical procedures were used to ameliorate the negative impacts of increased temperature; among them the dietary manipulation, which gains a great concern in different regions around the world. These nutritional manipulations are feed additives (natural antioxidants, minerals, electrolytes, phytobiotics, probiotics, fat, and protein), feed restriction, feed form, drinking cold water and others. However, in the large scale of poultry industry, only a few of these strategies are commonly used. The current review article deliberates the different practical applications of useful nutritional manipulations to mitigate the heat load in poultry. The documented information will be useful to poultry producers to improve the general health status and productivity of heat-stressed birds via enhancing stress tolerance, oxidative status and immune response, and thereby provide recommendations to minimize production losses due to heat stress in particular under the growing global warming crisis.

Morroniside protects OLN-93 cells against H2O2-induced injury through the PI3K/Akt pathway-mediated antioxidative stress and antiapoptotic activities

Neurodegenerative disorders, including spinal cord injury (SCI), result in oxidative stress-induced cell damage. Morroniside (MR), a major active ingredient of the Chinese herb Shan Zhu Yu, has been shown to ameliorate oxidative stress and inflammatory response. Our previous study also confirmed that morroniside protects SK-N-SH cell line (human neuroblastoma cells) against oxidative impairment. However, it remains unclear whether MR also plays a protective role for oligodendrocytes that are damaged following SCI. The present study investigated the protective effects of MR against hydrogen peroxide (H₂O₂)-induced cell death in OLN-93 cells. MR protected OLN-93 cells from H₂O₂-induced injury, attenuated H₂O₂-induced increase in reactive oxygen species (ROS) and malondialdehyde (MDA) levels, and blocked the reduction of mitochondrial membrane potential (MMP) induced by H2O2. MR enhanced the activity of the antioxidant enzyme superoxide dismutase (SOD) and suppressed H₂O₂-induced downregulation of the antiapoptotic protein Bcl-2 and activation of the proapoptotic protein caspase-3. Finally, we found that LY294002, a specific inhibitor of the PI3K/Akt pathway, inhibited the protective effect of MR against H₂O₂-induced OLN-93 cell injury in the MTT and TUNEL assays. LY294002 also inhibited the expression of SOD and Bcl-2, and increased the expression of iNOS and c-caspase-3 induced by MR treatment. MR exerts protective effects against H₂O₂-induced OLN-93 cell injury through the PI3K/Akt signaling pathway-mediated antioxidative stress and antiapoptotic activities. MR may provide a potential strategy for SCI treatment or other related neurodegeneration.