The global population has increased with swift urbanization in developing countries, and it is likely to result in a high demand for animal-derived protein-rich foods. Animal farming has been constantly affected by various stressful conditions, which can be categorized into physical, environmental, nutritional, and biological factors. Such conditions could be exacerbated by banning on the use of antibiotics as a growth promoter together with a pandemic situation including, but not limited to, African swine fever, avian influenza, and foot-and-mouth disease. To alleviate these pervasive tension, various immunomodulants have been suggested as alternatives for antibiotics. Various studies have investigated how stressors (i.e., imbalanced nutrition, dysbiosis, and disease) could negatively affect nutritional physiology in chickens. Importantly, the immune system is critical for host protective activity against pathogens, but at the same time excessive immune responses negatively affect its productivity. Yet, comprehensive review articles addressing the impact of such stress factors on the immune system of chickens are scarce. In this review, we categorize these stressors and their effects on the immune system of chickens and attempt to provide immunomodulants which can be a solution to the aforementioned problems facing the chicken industry.

In the modern pig production, pigs are weaned at early age with immature intestine. Dietary and environmental factors challenge the intestine, specifically the jejunum, causing inflammation and oxidative stress followed by destruction of epithelial barrier and villus structures in the jejunum. Crypt cell proliferation increases to repair damages in the jejunum. Challenges to maintain the intestinal health have been shown to be related to changes in the profile of mucosa-associated microbiota in the jejunum of nursery pigs. All these processes can be quantified as biomarkers to determine status of intestinal health related to growth potential of nursery pigs. Nursery pigs with impaired intestinal health show reduced ability of nutrient digestion and thus reduced growth. A tremendous amount of research effort has been made to determine nutritional strategies to maintain or improve intestinal health and microbiota in nursery pigs. A large number of feed additives have been evaluated for their effectiveness on improving intestinal health and balancing intestinal microbiota in nursery pigs. Selected prebiotics, probiotics, postbiotics, and other bioactive compounds can be used in feeds to handle issues with intestinal health. Selection of these feed additives should aim modulating biomarkers indicating intestinal health. This review aims to define intestinal health and introduce examples of nutritional approaches to handle intestinal health in nursery pigs.

Phytobiotics, also known as phytochemicals or phytogenics, have a wide variety of biological activities and have recently emerged as alternatives to synthetic antibiotic growth promoters. Numerous studies have reported the growth-promoting effects of phytobiotics in chickens, but their precise mechanism of action is yet to be elucidated. Phytobiotics are traditionally known for their antioxidant activity. However, extensive investigations have shown that these compounds also have anti-inflammatory, antimicrobial, and transcription-modulating effects. Phytobiotics are non-nutritive constituents, and their bioavailability is low. Nonetheless, their beneficial effects have been observed in several tissues or organs. The health benefits of the ingestion of phytobiotics are attributed to their antioxidant activity. However, several studies have revealed that not all these benefits could be explained by the antioxidant effects alone. In this review, I focused on the bioavailability of phytobiotics and the possible mechanisms underlying their overall effects on intestinal barrier functions, inflammatory status, gut microbiota, systemic inflammation, and metabolism, rather than the specific effects of each compound. I also discuss the possible mechanisms by which phytobiotics contribute to growth promotion in chickens.

Broiler chickens grow rapidly, and their nutrient requirements change daily. However, broilers are fed three to five diet phases, meaning nutrients are under or oversupplied throughout production. Increasing diet phases improves production efficiency as there is less time in the production cycle that nutrients are in under or over-supply. Nevertheless, the process of administering four or more diets is costly and often impractical. New technologies are now available to blend feed to match the daily nutrient requirements of broilers. Thus, the aim of this review is to evaluate previous studies measuring the impact of increasing feed phases on nutrient utilisation and growth performance, and review recent studies taking this concept to the extreme; precision nutrition - feeding a new diet for each day of the production cycle. This review will also discuss how modern precision feeding technologies have been utilised and the potential that new technologies may bring to the poultry industry. The development of a precision nutrition regime which targets daily requirements by blending dietary components on farm is anticipated to improve the efficiency of production, reduce production cost and therefore improve sustainability of the industry. There is also potential for precision feeding technology along with precision nutrition strategies to deliver a plethora of other management and economic benefits. These include increased fluidity to cope with sudden environmental or market changes, and the ability to alter diets on a farm by farm level in a large, integrated operation. Thus, the future possibilities and practical implications for such technologies to generate a paradigm shift in feed formulation within the poultry industry to meet the rising demand for animal protein is also discussed.

Objective: The effect of garlic powder (GP) and phenyl acetic (PA) acid throughout the fattening period of broiler chickens on performance, blood parameters, immune, and antioxidant parameters as well as carcass traits was evaluated. Methods: A total of 210 day-old Cobb broiler chicks were randomly distributed into seven dietary treatments having five replications with six chicks per replicate. The first group (control) fed a basal diet without supplements, whereas the 2nd, 3rd, and 4th group were fed basal diet plus 0.25, 0.50, and 0.75 g GP/kg diet, respectively and the group 5th, 6th, and 7th were fed on the basal diet plus 0.25, 0.50, and 0.75 g PA/kg diet. Results: Broiler body weight and gain at 21 and 42 days were increased (p<0.05) with diets supplemented with GP and PA. Red blood cells and hemoglobin were improved in chickens fed diets enriched with GP. Broiler chickens received diets containing either GP or PA recorded the higher values (p<0.05) of total protein, globulin, high-density lipoprotein, immunoglobulin M (IgM), and IgG, superoxide dismutase and total antioxidant capacity; while, blood total cholesterol, low-density lipoprotein, aspartate-aminotransferase, and malondialdehyde were lowered (p<0.05) compared to control-diet. Liver and immune-related organs weight were improved (p<0.05) in broilers fed diet supplemented with GP and PA. Conclusion: Feeding of GP or PA in diet had positive effects on performance traits and immunological, antioxidant and physiological status of broilers. Thus, the use of tested feed additives as an eco-friendly alternative to antibiotics produced a positive effect on animal health.

Objective: Wheat bran (WB) was co-fermented with Aspergillus oryzae and phytase (Phy) to determine whether co-fermentation improve WB phosphorus and fiber utilization in Isa-brown layers. Methods: A total of 112 Isa brown layer were randomly divided into 7 treatments with 8 replicates per a treatment and 2 hens per a replicate. The treatments included basal diet (control), basal diet supplemented with 250 unit/kg Phy (control+Phy), diet with 10% WB (10% WB), diet with 5% WB and 250 unit/kg Phy (5% WB+Phy) diet with 10% WB and 250 unit/kg Phy (10% WB+Phy), diet with 5% fermented WB supplemented with molasses and phy (PCFWH) and 125 unit/kg Phy (5% PCFWH), and diet with 10% PCFWH (10% PCFWH). The intestinal microbial population, intestinal morphology, serum antioxidant enzyme activities, and excreta phosphorus content were assessed. Results: In PCFWH, spore counts, protease activity, xylanase activity, and ferulic acid were 8.50 log/g dry matter (DM), 190 unit/g DM, 120 unit/g DM, and 127 ㎍/g, respectively. Xylobiose and xylotriose were released in PCFWH, while they were not detectable in WB. Antioxidant capacity was also enhanced in PCFWH compared to WB. The 10% WB+Phy and 10% PCFWH groups produced higher egg mass, but hens fed 5% WB+Phy had the lowest amount of feed intake. Eggs from 10% PCFWH had better eggshell weight, eggshell strength, and eggshell thickness. Birds fed with 10% PCFWH also had higher serum superoxide dismutase and catalase activities. Compare to control, 10% PCFWH significantly reduced excreta phosphorus content. Conclusion: Diet inclusion of 10% PCFWH improved egg quality, antioxidant status, and excreta phosphorus content of laying hens.

Objective: The present study was conducted to investigate the effects of lycopene on growth performance, abdominal fat deposition, serum lipids levels, activities of hepatic lipid metabolism related enzymes and genes expression in broiler chickens. Methods: A total of 256 healthy one-day-old male Arbor Acres broiler chicks were randomly divided into four groups with eight replicates of eight birds each. Birds were fed basal diet supplemented with 0 (control), 100, 200, and 400 mg/kg lycopene, respectively. Results: Dietary 100 mg/kg lycopene increased the body weight at 21 day of age compared to the control group (p<0.05). Compared to the basal diet, broilers fed diet with 100 mg/kg lycopene had decreased abdominal fat weight, and broilers fed diet with 100 and 200 mg/kg lycopene had decreased abdominal fat percentage (p<0.05). Compared to control, diets with 100, 200, and 400 mg/kg lycopene reduced the levels of total triglyceride and total cholesterol in serum, and diets with 100 and 200 mg/kg lycopene reduced the level of serum low density lipoprotein cholesterol (p<0.05). The activity of fatty acid synthase (FAS) in 400 mg/kg lycopene treated broilers and the activity of acetyl-CoA carboxylase (ACC) in 100, 200, and 400 mg/kg lycopene treated broilers were lower than those fed basal diet (p<0.05). Lycopene increased the mRNA abundance of adenosine monophosphate activated protein kinase α (AMPK-α), whereas decreased the mRNA abundance of sterol regulatory element-binding protein 1, FAS, and ACC compared to the control group (p<0.05). Conclusion: Dietary lycopene supplementation can alleviate abdominal fat deposition and decrease serum lipids levels, possibly through activating the AMPK signaling pathway, thereby regulating lipid metabolism such as lipogenesis. Therefore, lycopene or lycopene-rich plant materials might be added to poultry feed to regulate lipid metabolism.

Objective: This study compared the catechin composition of different tea byproducts and investigated the effects of dietary supplementation with green tea byproducts on the accumulation of abdominal fat, the modulation of lipid metabolism, and the inflammatory response in red feather native chickens. Methods: Bioactive compounds were detected, and in vitro anti-obesity capacity analyzed via 3T3-L1 preadipocytes. In animal experiments, 320 one-day-old red feather native chickens were divided into 4 treatment groups: control, basal diet supplemented with 0.5% Jinxuan byproduct (JBP), basal diet supplemented with 1% JBP, or basal diet supplemented with 5×106 colony-forming unit (CFU)/kg Bacillus amyloliquefaciens+5×106 CFU/kg Saccharomyces cerevisiae (BA+SC). Growth performance, serum characteristics, carcass characteristics, and the mRNA expression of selected genes were measured. Results: This study compared several cultivars of tea, but Jinxuan showed the highest levels of the anti-obesity compound epigallocatechin gallate. 3T3-L1 preadipocytes treated with Jinxuan extract significantly reduced lipid accumulation. There were no significant differences in growth performance, serum characteristics, or carcass characteristics among the groups. However, in the 0.5% JBP group, mRNA expression of fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC) were significantly decreased. In the 1% JBP group, FAS, ACC and peroxisome proliferator-activated receptor γ levels were significantly decreased. Moreover, inflammation-related mRNA expression levels were decreased by the addition of JBP. Conclusion: JBP contained abundant catechins and related bioactive compounds, which reduced lipid accumulation in 3T3-L1 preadipocytes, however there was no significant reduction in abdominal fat. This may be due to a lack of active anti-obesity compounds or because the major changes in fat metabolism were not in the abdomen. Nonetheless, lipogenesis-related and inflammation-related mRNA expression were reduced in the 1% JBP group. In addition, dietary supplementation with tea byproducts could reduce the massive amount of byproducts created during tea production and modulate lipid metabolism and the inflammatory response in chickens.

Objective: This study evaluated the effects of feeding diets naturally contaminated with deoxynivalenol (supplemental 2 mg/kg) on health, growth, and the effects of a mycotoxin-detoxifying additive in newly-weaned pigs. Methods: Thirty-six pigs (27 day-old) were housed individually and assigned to 3 treatments for 5 weeks: CON (diet containing minimal deoxynivalenol), MT (diet with supplemental 1.9 mg/kg of deoxynivalenol), and MT+D (MT + mycotoxin-detoxifying additive, 0.2%, MegaFix, ICC, São Paulo, Brazil). The mycotoxin-detoxifying additive included bentonite, algae, enzymes, and yeast. Blood was taken at week 2 and 5. Jejunal tissue were taken at week 5. Data were analyzed using the MIXED procedure of SAS. Results: Pigs fed MT+D tended to have decreased (p = 0.056) averaged daily feed intake during week 1 than MT. At week 2, serum aspartate aminotransferase/alanine aminotransferase in MT tended to be lower (p = 0.059) than CON, whereas it was increased (p<0.05) for MT+D than MT, indicating hepatic damages in MT and recovery in MT+D. Pigs fed MT had lower (p<0.05) blood urea nitrogen/creatinine than CON, supporting hepatic damage. At week 5, pigs fed MT tended to have reduced (p = 0.079) glucose than CON, whereas it was increased (p<0.05) for MT+D than MT, indicating impaired intestinal glucose absorption in MT, which was improved in MT+D. Pigs fed CON tended to have increased (p = 0.057) total glutathione in jejunum than MT, indicating oxidative stress in MT. Pigs fed MT+D had a reduced (p<0.05) proportion of Ki-67-positive cells in jejunum than MT, indicating lower enterocyte proliferation in MT+D. Conclusion: Feeding supplemental 1.9 mg/kg of deoxynivalenol reduced growth and debilitated hepatic health of pigs, as seen in leakage of hepatic enzymes, impaired nitrogen metabolism, and increase in oxidative stress. The mycotoxin-detoxifying enhanced hepatic health and glucose levels, and attenuated gut damage in pigs fed deoxynivalenol contaminated diets.

Objective: Effects of inulin supplementation in diet of Haidong chicks under hypoxic conditions on production performance, intestinal morphologic change, microflora contents and the incidence of ascites were studied. Methods: Commercial male chicks (360) were randomly divided into 6 groups and were fed diets supplemented with 0, 0.05, 0.075, 0.1, 0.125, and 0.15 g/kg of inulin, respectively. Results: The body weight gain and feed intake were improved in chicks fed the diets supplemented with 0.1 and 0.125 g/kg of inulin, from d 1 to d 42 (p<0.05); moreover, blood parameters were positively affected when inulin was included in the diets and the thickness of the intestinal wall and muscle tissue in duodenum, jejunum, and ileum tended to increase (p<0.05), and the villi height and crypt depth in duodenum, jejunum, and ileum (p<0.05). Regarding the number of goblet cells in duodenum, jejunum and ileum tended to increase when chicks were fed the diets supplemented with 0.075, 0.1, 0.125, and 0.15 g/kg (p<0.05) of inulin. When chicks were fed diets supplemented with 0.75 or 0.1 g/kg of inulin, a significant reduction of Escherichia coli counts in the cecum was observed; for a contrary, a significant increment of Bifidobacterium and Lactobacillus was observed in cecum and ileum. Finally, supplementing the feed with inulin determined an overall reduction of ascites incidences in comparison to the control group. Conclusion: Thus, the results observed in the present study clearly suggest that the diet supplementation with a quantity of inulin ranging between 0.1 and 0.125 g/kg, can improve growth performances, intestinal morphology, internal microbial balance and ascites incidence, in broiler chicks raised at high altitude area. Even though these findings may be of interest for the poultry industry, they may particularly be relevant in those areas characterized by high altitude such as Northwest China regions.

Objective: An experiment was conducted to investigate the effects of Achyranthes japonica extracts (AJE) on the growth performance, nutrient digestibility, fecal microbial shedding, and fecal gas emission of growing pigs. Methods: A total of 180 ([Landrace×Yorkshire]×Duroc) growing pigs with initial body weight (BW) of 23.94±1.54 kg were used in this study to investigate the effects of AJE as a feed additive. Dietary treatments included: i) CON (basal diet), ii) TRT1 (basal diet+0.05% AJE), and iii) TRT2 (basal diet+0.10% AJE). Results: As a result of the dietary supplementation of 0% to 0.10% AJE, a linear increase of BW (p<0.05) on d 21 and 42, a linear increase of average daily gain (ADG) (p<0.05) during d 21 to 42, a trend in linear increase of ADG (p<0.10) during d 0 to 21 and d 0 to 42, a linear increase of gain to feed ratio (G:F) (p<0.05) during d 0 to 42, and a tendency in the linear increase of G:F during d 21 to 42 were observed in this study. Additionally, dietary supplementation of 0% to 0.10% AJE had a linear increase (p<0.05) on the apparent total tract digestibility of dry matter (DM) and energy, a linear increase (p<0.05) on lactic acid bacteria counts, a tendency in reducing (linear effect, p<0.10) coliform bacteria counts, and a linear decrease (p<0.05) in excreta H2S emission content in growing pigs. Conclusion: In conclusion, the results suggested that AJE had the potential to enhance growth performance, DM and energy digestibility, and fecal lactic acid bacteria counts, and decrease the fecal coliform bacteria counts and excreta H2S emission in growing pigs.

Objective: This study aims to evaluate the influence of dietary flavonoids on the growth performance, blood and intestinal profiles, and carcass characteristics of broilers by employing a meta-analysis method. Methods: A database was built from published studies which have reported on the addition of various levels of flavonoids from herbs into broiler diets and then monitored growth performance, blood constituents, carcass proportion and small intestinal morphology. A total of 42 articles were integrated into the database. Several forms of flavonoids in herbs were applied in the form of unextracted and crude extracts. The database compiled was statistically analyzed using mixed model methodology. Different studies were considered as random effects, and the doses of flavonoids were treated as fixed effects. The model statistics used were the p-values and the Akaike information criterion. The significance of an effect was stated when its p-value was <0.05. Results: Dietary flavonoids increased (quadratic pattern; p<0.05) the average daily gain of broilers in the finisher phase. There was a reduction (p<0.01) in the feed conversion ratio of the broilers both in the starter (linear pattern) and finisher phases (quadratic pattern). The mortality rate tended to decrease linearly (p<0.1) with the addition of flavonoids, while the carcass parameter was generally not influenced. A reduction (p<0.001) in cholesterol and malondialdehyde concentrations (both linearly) was observed, while super oxide dismutase activity increased linearly (p<0.001). Increasing the dose of flavonoids increased (p<0.01) the villus height (VH) and villus height and crypt depth (VH:CD) ratio (p<0.05) in the duodenum. Similarly, the VH:CD ratio was elevated (p<0.001) in the jejunum following flavonoid supplementation. Conclusion: Increasing levels of flavonoids in broilers diet leads to an improvement in growth performance, blood constituents, carcass composition and small intestinal morphology.

Objective: Astaxanthin is a natural super antioxidant. The present study was carried out to investigate the effect of astaxanthin rich Phaffia rhodozyma (PR) supplementation in diets on laying production performance, egg quality, antioxidant defenses and immune defenses in laying hens. Methods: A total of five hundred and twelve 60-week-old Lohmann Brown laying hens (2,243±12 g) were randomly assigned to four groups, each including 4 replicates with 32 birds per replicate. Astaxanthin rich PR was added to corn-soybean meal diets to produce experimental diets containing 0 (Control), 800 mg/kg, 1,200 mg/kg, and 1,600 mg/kg PR, respectively. The astaxanthin content in the diet was 0.96 mg/kg, 1.44 mg/kg and 1.92 mg/kg respectively. Results: Results showed that dietary PR supplementation tended to increase daily feed intake (p = 0.0512). There was no effect of astaxanthin rich PR on Haugh units, albumen height, egg shape index, eggshell strength, and eggshell thickness at weeks 6 (p>0.05). However, egg yolk color was significantly improved (p<0.05). In addition, astaxanthin rich PR supplementation significantly increased serum glutathione peroxidase and superoxide dismutase activity (p<0.05), increased serum immunoglobulin G content (p<0.05), and reduced malondialdehyde content (p<0.05) in laying hens. Conclusion: In conclusion, astaxanthin rich PR can improve the color of egg yolk, enhance the antioxidant defenses, and regulate the immune function.

Objective: Seaweeds could be an alternative and functional feed resource. The purpose of this experiment is to investigate the effect of dietary supplementation of Sargassum meal on laying performance and egg quality of layers. Methods: Two hundred 36-wk-old layers were divided into five treatment groups. Each treatment had four replicates with 10 hens per experimental unit. The corn-soybean meal basal diet was formulated as control group. Sargassum meals were included 0%, 1%, 2%, 3%, or 5% to diets for five treatment groups, respectively. Treatment groups were isocaloric-isonitrogenous diets. Laying performance and egg quality were measured for eight weeks. Results: Sargassum meal supplementation did not affect daily feed intake. Supplementation 1% to 3% of Sargassum meal in diets increased daily laying rate and egg mass compared with those from control group (p<0.05). Egg qualities among five groups were all similar. Supplementation of 3% Sargassum meal increased the lightness of egg yolk (p<0.05). Eggs produced from layers fed 1% and 2% Sargassum meal had a higher consumer's acceptability than the control group (p<0.05). In blood characteristics, contents of glucose, nitrogen, triiodothyronine (T3) and thyroxine (T4) increased as the increase of supplementation ratio of Sargassum meal (p<0.05). In serum antibody titers, supplementation of 2% Sargassum meal stimulated a higher immunoglobulin M (IgM) level than that from control group (p<0.05). However, IgM content of layers fed diets with Sargassum meal ≥3% were decreased (p<0.05). There was no difference in IgA and IgG titers among groups. Conclusion: Supplementation of 1% to 3% Sargassum meal has shown to increase egg laying rate and egg mass of Leghorn layers. However, high supplementation (5%) would negatively affect laying performance. In consideration of laying performance, egg quality, consumer responses, and blood antibody, supplementation of Sargassum meal was suggested 2% in the diet for layers.

Objective: The aim of this study was to investigate the effects of Enteromorpha powder supplementation on reproduction-related hormones and genes in the late laying period of Zi geese. Methods: A total of 312 (1-year-old) Zi geese with similar laying rate were randomly divided into 2 groups with 6 replicates each, each with 21 female geese and 5 male geese. The control group was fed with a basal diet and the test group was fed with a diet containing 3% Enteromorpha powder. The trial period lasted for 7 weeks. Results: Our results showed that the laying rate was improved in the test group at each week of trial (p<0.01), and the levels of estradiol in serum and prolactin in ovary were increased compared with the control group (p<0.05). Conclusion: Based on above results, Enteromorpha powder supplementation at 3% could promote reproductive performance during the late laying period of Zi geese.

Objective: This experiment was conducted to find out the immunological effects of wheat phytase when long-chain inorganic polyphosphate (polyP) treated with wheat phytase was added to a macrophage cell line, Raw 264.7, when compared to intact long-chain polyP. Methods: Nitric oxide (NO) production of Raw 264.7 cells exposed to P700, a long-chain polyP with an average of 1,150 phosphate residues, treated with or without wheat phytase, was measured by Griess method. Phagocytosis assay of P700 treated with or without phytase in Raw 264.7 cells was investigated using neutral red uptake. The secretion of tumor necrosis factor α (TNF-α) by Raw 264.7 cells with wheat phytase-treated P700 compared to intact P700 was observed by using Mouse TNF-α enzyme-linked immunosorbent assay kit. Results: P700 treated with wheat phytase effectively increased NO production of Raw 264.7 cells by 172% when compared with intact P700 at 12 h exposure. At 5 mM of P700 concentration, wheat phytase promoted NO production of macrophages most strongly. P700, treated with wheat phytase, stimulated phagocytosis in macrophages at 12 h exposure by about 1.7-fold compared to intact P700. In addition, P700 treated with wheat phytase effectively increased in vitro phagocytic activity of Raw 264.7 cells at a concentration above 5 mM when compared to intact P700. P700 dephosphorylated by wheat phytase increased the release of TNF-α from Raw 264.7 cells by 143% over that from intact P700 after 6 h exposure. At the concentration of 50 μM P700, wheat phytase increased the secretion of cytokine, TNF-α, by 124% over that from intact P700. Conclusion: In animal husbandry, wheat phytase can mitigate the long-chain polyP causing damage by improving the immune capabilities of macrophages in the host. Thus, wheat phytase has potential as an immunological modulator and future feed additive for regulating immune responses caused by inflammation induced by long-chain polyP from bacterial infection.