Antioxidant Status, Blood Constituents and Immune Response of Broiler Chickens Fed Two Types of Diets with or without Different Concentrations of Active Yeast

Phenomenological and mechanistic insights into potential dietary nucleotide - probiotic synergies in layer chickens: A review

Despite their growing popularity as alternatives to antibiotic growth promoters (AGPs), the individual effects of nucleotides and probiotics on poultry gut functionality remain poorly understood. In addition, inconsistent outcomes are quite common in studies where these two additives have been used separately to modify gut function and related parameters in birds. These inconsistencies, which have limited the potential of probiotics and nucleotides as AGP replacements, stem from various factors and need to be addressed. Combining probiotics and nucleotides could potentially enhance their effectiveness and lead to more consistent outcomes in layer chickens. Since their mechanisms of action complement each other, some level of synergy is expected when used together. Both additives have been shown to support gut health, boost immune function, and improve performance in chickens when used individually. However, no studies have investigated the possible synergistic effects of nucleotides and probiotics in poultry. This review makes the case for combined use of probiotics and nucleotides in layer chickens by providing phenomenological and mechanistic insights into hypothetical synergistic effects. This paper highlights the need for AGP alternatives and reviews studies on the effects and mechanisms of probiotics and nucleotides in layer chickens when used individually. We then propose potential mechanisms for their synergistic effects on gut health, performance, and egg quality based on logical deductions from observed biological responses. These proposed mechanisms are hypothetical and require experimental validation. Finally, the review explores how this synergy could lead to more consistent outcomes and enhance the feasibility of AGP-free egg production.

Evaluation of Clostridium autoethanogenum protein as a new protein source for broiler chickens in replacement of soybean meal

OBJECTIVE

The object of this study was to investigate the effect of replacing soybean meal with Clostridium autoethanogenum protein (CAP) in broiler diets on growth performance, blood indicators, antioxidant capacity, and immune function.

METHODS

A total of 180 Arbor Acres broilers were randomly divided into three treatments, each treatment with six replicates and 10 broilers per replicate for a 42-day feeding trial. The control group (CON) was fed corn-soybean meal based diet. The CAP-1 and CAP-2 groups were considered to use CAP to replace 25% or 50% of soybean meal in the diet, respectively. The average daily gain and average daily feed intake of broilers at 1 to 21 d, 22 to 42 d, and 1 to 42 d were measured, and the feed conversion ratio was calculated. At the 42nd day of age, two broilers with similar weights and fasted for 12 h were selected in each replicate for blood collection from the brachial wing vein. The blood routine indicators, serum biochemical indicators, serum antioxidant capacity, and immunoglobulin content of broiler chickens were measured.

RESULTS

Replacement of soybean meal with 25% (CAP-1) and 50% (CAP-2) CAP significantly increased the average daily gain of 22 to 42 d and 1 to 42 d and decreased the average daily feed intake and feed conversion rate (p<0.05). The CAP-1 group, and CAP-2 group significantly increased hemoglobulin in the blood of broilers, while the CAP-2 group increased hematocrit content (p<0.05). Compared with the control group, the contents of superoxide dismutase and immunoglobulin A in serum of the CAP-2 group were significantly increased, while the contents of malondialdehyde in CAP group were significantly decreased (p<0.05).

CONCLUSION

Replacing soybean meal with CAP led to significant improvements in the growth performance, antioxidant capacity, and immunoglobulin content of broilers.

Lignocellulose and probiotic supplementation in broiler chicken diet: effect on growth performance, digestive health, litter quality, and genes expression

Three hundred one-day-old Avian 48 broiler chicks were used to investigate the effect of lignocellulose (LC) and probiotic supplementation in broiler chicken diet on growth performance, digestive health, litter quality, and some gene expression. Experimental treatments consisted of 3 × 2 factorial arrangements with 3 levels of LC without or with probiotics to formulate 6 experimental groups. Groups 1, 2, and 3 were fed on the basal diet with dietary LC inclusion at 0, 0.5, and 1.0%, respectively, while groups 4, 5, and 6 were fed on the previously mentioned design with Bacillus subtilis at 100 gm/ton. The results revealed that Dietary LC inclusion nonsignificantly (P ≥ 0.05) reduced body weight (BW), body weight gain (BWG), and feed intake. Meanwhile, B. subtilis supplementation improved BW and BWG and enhanced the effect of LC on the broilers' weight. The group fed a 0.5% LC and B. subtilis-supplemented diet recorded the best (P ≥ 0.05) BW, BWG, FCR, PER, EEU, and PI. LC and or B. subtilis supplementation improved carcass traits of broiler (higher dressing% with lower abdominal fat% compared with a control group), intestinal health, and absorptive capacity. LC potentiates the effect of B. subtilis supplementation in broilers' diet in modulating intestinal microflora (lowered (P ≥ 0.05) cecal Coliform and increased Lactobacillus counts), the highest Coliform counts were recorded in group fed 0.5 or 1.0% LC plus B. subtilis. LC at 0.5 or 1.0% and or B. subtilis supplementation reduced (P ≥ 0.05) litter moisture% at the 2nd, 4th, and 6th wk compared to the control group. Dietary inclusion of LC and or B. subtilis supplementation significantly (P < 0.001) up-regulated hepatic growth-related genes (growth hormone receptor (GHR) and insulin growth factor1 (IGF-1)) and antioxidant-related genes (superoxide dismutase 1 (SOD1), glutathione peroxidase (GPX1) and uncoupling protein (UCP) and down-regulated (P < 0.001) splenic toll-like receptor 4 (TLRP) gene expression while had no significant effect on splenic interleukin 8 (IL8) and tumor necrosis factor (TNF) with the best-obtained results with 1.0% followed by 0.5% LC with B. subtilis supplementation. We concluded that dietary LC and/or B. subtilis supplementation positively affected the growth performance, feed efficiency, carcass quality, intestinal absorptive capacity and health, litter quality and growth, and antioxidant and immune-related gene expression.

Early Feeding Strategy Mitigates Major Physiological Dynamics Altered by Heat Stress in Broilers

Heat stress is one of the stressors that negatively affect broiler chickens, leading to a reduction in production efficiency and profitability. This reduction affects the economy in general, especially in hot and semi-hot countries. Therefore, improving heat tolerance of broiler chicks is a key to sustained peak performance, especially under adverse environmental heat stress conditions. The present study investigated three early feed withdrawal regimes (FWD) as a potential mitigation for thermal stress exposure. A total of 240 unsexed one-day-old Cobb-500 chicks were randomly recruited to one of four experimental groups using a completely randomized design (10 birds × 6 replicates). The experimental groups included the control group with no feed withdrawal (control), while the other three groups were subjected to early feed withdrawal for either 24 h on the 5th day of age (FWD-24), 12 h on the 3rd and 5th day of age (FWD-12), or 8 h on the 3rd, 4th, and 5th day of age (FWD-8), respectively. Production performance was monitored throughout the experiment. Meanwhile, blood and liver samples were taken at the end of the experimental period to evaluate major physiological dynamic changes. Our findings demonstrated that under chronic heat stress conditions, FWD treatments significantly improved broilers' production performance and enhanced several physiological parameters compared with the control. Serum levels of thyroid hormones were elevated, whereas leptin hormone was decreased in FWD groups compared with the control. Moreover, serum total protein, globulin, and hemoglobin levels were higher, while total cholesterol and uric acid were lower in the FWD groups. Furthermore, FWD groups showed significantly higher antioxidant marker activity with a significantly lower lipid peroxidation level. Immunoglobulin levels, lysozyme, complement factor C3, and liver heat shock protein 70 (HSP70) concentration were also elevated in FWD compared with the control. Also, serum interleukin-1β (IL-1β) and interferon-gamma (IFN-γ) significantly increased with FWD. Based on our findings, early feed withdrawal can be applied as a promising non-invasive nutritional strategy for broilers reared under chronic heat stress conditions. Such a strategy promotes the alleviation of the deleterious effects of heat stress on broiler performance, immunity, and redox status, owing to the onset of physiological adaptation and the development of thermotolerance ability.

Chromium propionate supplementation to energy- and protein-reduced diets reduces feed consumption but improves feed conversion ratio of yellow-feathered male broilers in the early period and improves meat quality

Growth performance and carcass traits may be retarded by low nutrient density diets. Organic chromium propionate (CrProp) can improve growth, carcass traits, and meat quality in farmed lambs, white broilers, and fish. Limited data regarding CrProp's impacts on yellow-feathered broilers are available. Eight hundred yellow-feathered male broilers (1-day old) were randomly allocated to 4 dietary groups and reared for 56 d. The trial was a 2 (dietary nutrient density) ×2 (CrProp) factorial arrangement with 4 diets: regular nutrient diet and low nutrient density (LND, reduction in metabolizable energy by 81 kcal and crude protein by 0.43%) diet supplemented with or without 200 mg/kg CrProp. Broilers were euthanized at d 56 after blood collection. The results indicated that the LND diet led to greater average daily feed intake (ADFI) from d 1 to 42 and feed conversion ratio (FCR) from d 22 to 42 (P < 0.05). Supplementation of CrProp improved body weight (BW) from d 1 to 56, average daily gain (ADG), and FCR during d 1 to 42 but reduced ADFI during d 1 to 21, as well as lowered abdominal fat percentage (P < 0.05). Supplementation with CrProp to regular and LND diets reduced ADFI but improved FCR from d 1 to 21 (P < 0.05). The LND diet lowered total antioxidant capacity (T-AOC) concentration and total superoxide dismutase (T-SOD) activity in the jejunal mucosa. CrProp elevated T-AOC levels and glutathione peroxidase activity (GSH-Px, P < 0.05). Dietary CrProp upregulated (P < 0.05) the expression of fatty acid transporter (FABP1) gene and peptide transporter (Pept1) gene. CrProp administration increased jejunal FABP1 expression and lowered cooking loss of breast meat (P < 0.05) in the LND group while reducing shear force (P = 0.009) of broilers treated by regular diet. In summary, CrProp administration to the LND diet can improve growth performance in the starter period and meat quality on d 56, possibly through upregulated nutrient transporter gene expression in the jejunum and enhanced antioxidant capability.

Impact of β-glucan dietary supplementation on productive, reproductive performance and physiological response of laying hens under heat stress conditions

The exploration for effective in-feed additives is growing owing to the global climatic change trend to alleviate the negative effects of heat stress in laying hens. This research assessed the potential of using B-glucan (G) as an antiheat stress agent in Matrouh laying hens subjected to early heat shock programs during the growing period. Factorial design (3 × 3) was used, including 3 levels of heat stress (control, heat shock at 3 d and at 3 d and 8 wk of age) and 3 levels of β-glucan (0, 100, and 200 mg β-glucan /kg diet). During the first 12 wk of egg production (EP), treatments were exposed to heat challenge. The results revealed that heat shock program applications at 3 d and 8 wk of age significantly decreased body weight at 36 wk of age (P < 0.05) and reduced (P < 0.05) feed intake (FI). While significantly (P < 0.05) improved feed conversion ratio (FCR), hemoglobin, RBCs, WBCs, immunoglobulin M (IgM), immunoglobulin G (IgG), and Heat shock protein (HSP70) of the Liver (P < 0.01) as compared with the control group. At the same time, there was a decrease in lymphocyte%, H/L ratio, cortisol, and T3 compared to the thermo-neutral control. When compared to the control group, hens fed a diet containing 200 mg of βG significantly (P < 0.05) improved body weight at 16 wk and final weight at 36 wk, feed conversion (FCR) (g. feed/g. egg mass), hen-day egg production, and egg mass, as well as the digestibility coefficients of crude protein (CP), dry matter (DM), metabolizable energy (ME), and cortisol. The interactions between heat chock programs and βG levels were nonsignificant for the most studied traits except daily feed intake. Therefore, the early heat shock exposure 2 times and supplementation of Β-glucan (βG) at 200 mg/kg diet during the growth period for laying hens that are exposed to heat stress during the reproductive period could improve productive, reproductive performance, HSP70 level and enhance immunity responses.

A Technical Report on the Potential Effects of Heat Stress on Antioxidant Enzymes Activities, Performance and Small Intestinal Morphology in Broiler Chickens Administered Probiotic and Ascorbic Acid during the Hot Summer Season

Oxidative stress negatively affects the welfare of broiler chickens leading to poor productivity and even death. This study examined the negative effect of heat stress on antioxidant enzyme activities, small intestinal morphology and performance in broiler chickens administered probiotic and ascorbic acid during the hot summer season, under otherwise controlled conditions. The study made use of 56 broiler chickens; which were divided into control; probiotic (1 g/kg); ascorbic acid (200 mg/kg) and probiotic + ascorbic acid (1 g/kg and 200 mg/kg, respectively). All administrations were given via feed from D1 to D35 of this study. Superoxide dismutase, glutathione peroxidase and catalase activities were highly significant (p < 0.0001) in the treatment groups compared to the control. Performance indicators (water intake and body weight gain) were significantly higher (p < 0.05) in the probiotic and probiotic + ascorbic acid group. The height of duodenal, jejunal and ileal villi, and goblet cell counts of broiler chickens were significantly different in the treatment groups. In conclusion, the study showed that heat stress negatively affects the levels of endogenous antioxidant enzymes, performance and the morphology of small intestinal epithelium, while the antioxidants were efficacious in ameliorating these adverse effects.

Effects of Bacillus halophilus on growth, intestinal flora and metabolism of Larimichthys crocea

The incorporation of probiotics into the diet of large yellow croaker has been demonstrated by several studies to confer partial disease resistance. Bacillus halophilic isolated from the intestinal flora was used to study its effects on performance growth indicators, intestinal tissue structure, intestinal flora and the metabolism of Larimichthys crocea. A total of 180 fishes with an initial body weight of (164.00 ± 54.00) g were fed diets with three different concentrations of Bacillus halophilic: 0 cfu/mL (FC0, control group), 108 cfu/mL (FC8, treatment group), and 1012 cfu/mL (FC12, treatment group). The results showed that there were no significant differences in specific growth rate among all groups (P > 0.05). Compared to the FC0 group, the final body weight and Weight gain rate were significantly higher in FC8 and FC12 groups (P < 0.05). The Survival of the FC12 group significantly improved (P < 0.05). Compared to the FC0 group, crude protein content in muscle of the FC8 group significantly increased (P < 0.05), crude fat content significantly increased in the FC12 group (P < 0.05), crude protein content in whole fish experimental groups significantly increased (P < 0.05), and ash content significantly increased in the FC8 group (P < 0.05). In terms of antioxidant ability, the content of LZM in blood increased significantly in the FC8 group (P < 0.05), GSH content in liver of the FC12 group increased significantly (P < 0.05), while the content of MDA and AKP in blood and liver had no significant difference (P > 0.05). At the level of intestinal structure, there were no significant differences in villus height, crypt depth and goblet cell number between control group and treatment groups (P > 0.05). At the phylum level, Firmicutes was the dominant phylum, and the genus level, Lactobacillus and Bacteroides were the dominant bacteria in FC8 and FC12. A total of 1070 metabolites were identified, among which lipid metabolites accounted for 46.7%. Metabolites were involved in six main ways, mainly related to the metabolism of amino acids and lipids. The correlation analysis between microbes and metabolites showed that the intestinal flora of Larimichthys crocea could promote the synthesis of metabolites, among which Bacteroides and Megamonas could promote the synthesis of beneficial metabolites such as amino acids and vitamins. Through this study, we found that Bacillus halophilic can significantly improve growth, the antioxidant immunity ability and promote the expression of growth related metabolites, with the FC12 group being the better successful.

The impact of multi-enzyme fortification on growth performance, intestinal morphology, nutrient digestibility, and meat quality of broiler chickens fed a standard or low-density diet

This research aimed to study the impact of supplementation of three multi-enzyme levels (0, 0.1, and 0.2% of feed) and two levels of dietary treatments [standard diet (SD) and low-density diet (LDD)] on growth performance, carcass traits, digestibility, and meat quality of broilers from 1 to 38 days of age. A total of 216 1-day-old Arbor Acres broiler chicks were randomly assigned to a factorial experiment (2 × 3) comprising six dietary treatments, each with six replicates and each replicate with six chickens. The results showed that the LDD significantly reduced body weight gain by 5.0%, compared with the SD. Multi-enzymes significantly improved body weight gain and the production index (PI) relative to the SD. The feed conversion ratio was significantly enhanced with increased multi-enzymes from 1 to 21 days. A significant relation between the multi-enzyme concentration and type of dietary treatment was observed in body weight gain and feed conversion ratio from 1 to 21 days of age. Nitrogen-free extract digestibility was significantly increased by using the SD diet compared with using the LDD. Multi-enzyme supplementation improved the digestibility of dry matter, crude protein, crude fiber, and nitrogen-free extract in the LDD. A significant relationship was found between the multi-enzyme concentration and type of dietary treatment on the pancreas, liver, and intestinal length percentages. The meat dry matter concentration was significantly higher in the LDD group than in the SD group. The low-density diet significantly reduced the total revenue compared with the SD, whereas broilers fed the SD recorded significantly higher total revenue and economic efficiency than those fed the LDD. The low-density diet significantly increased economic efficiency compared with the SD. Multi-enzymes significantly increased the total revenue, net revenue, and economic efficiency than the standard set. In conclusion, using multi-enzymes in broiler diets improved body weight gain. The LDD with multi-enzymes showed enhanced body weight gain compared with the SD without multi-enzymes.

The relation between avian coronaviruses and SARS-CoV-2 coronavirus

The coronaviruses (CoVs) are a family of ribonucleic acid viruses that are present in both mammals and birds. SARS-CoV and MERS-CoV originated in bats, and there is a possibility that this could be the case for SARS-CoV-2 as well. There is already evidence that a probable intermediary host is responsible for the emergence of viruses in humans as was the case for SARS-CoVs and MERS-CoV. As the SARS-CoV-2 originated from a live animal market, there is always the question if domestic animals are susceptible to these viruses and the possible risk of zoonotic transmission with mammals, including humans. This uncertainty of the transmission of the COVID-19 virus between humans and animals is of great significance worldwide. Hence, this paper focuses on the avian CoVs and their possible relation and interaction with SARS-CoV-2.

Effects From Dietary Addition of Sargassum sp., Spirulina sp., or Gracilaria sp. Powder on Immune Status in Broiler Chickens

Algae are innovative and significant nutrient sources with various health benefits when used as additives in animal feed. The study aims to examine the effect of different inclusions of three algae species, Sargassum sp., Spirulina sp., and Gracilaria sp. on the immune response of broiler chickens, as measured by the cellular immune response, humoral immune response, intestinal microbial counts, hindgut acidosis, and hematological measures. Here is a list of the seven experimental treatments (TRT). TRT 1 was the control group without algae; TRT 2 was supplemented with Sargassum sp. at 1% of the diet; TRT 3 with Sargassum sp. at 2% of the diet; TRT 4 with Spirulina sp. at 5% of the diet; TRT 5 with Spirulina sp. at 7.5% of the diet; TRT 6 with Gracilaria sp. at 0.5% of the diet; and TRT 7 Gracilaria sp. at 1% of the diet. Each treatment involved five replicates with 17 broiler chickens each, and the analyses were triplicated. The results showed that including algae in the feed ration of broiler chickens induces a higher cellular response than the control group, represented by T-cell response in the wattle area (P = 0.037). Sargassum sp. at 1 and 2% enhanced IgA antibody titers significantly and Gracilaria sp. at 5% enhanced IgY antibody titers, P = 0.045 and P = 0.030, respectively. All algal inclusions inhibited the growth of Salmonella sp. and improved LAB counts in the intestine of broilers, excepting the Gracilaria sp. at 0.5%, where LAB counts were similar to the control group. The E. coli counts decreased numerically but not significantly. Blood lymphocytes were enhanced while white blood cells (WBC) and heterophils were decreased as a results of algal inclusions. In conclusion, supplementing broiler chickens with algae could enhance their cellular and humoral immune status and promote healthy microflora in their guts.

Dietary Supplementation of Fructooligosaccharides Enhanced Antioxidant Activity and Cellular Immune Response in Broiler Chickens

This study investigated the impact of various concentrations of fructooligosaccharides (FOS) prebiotic on the production performance, antioxidant status, and immune response of broiler chicken. The FOS was used at 0, 0.3, 0.5, and 0.7%. The cycle included 340 broilers distributed into 4 batteries, with 85 broiler chickens in each battery. There were 5 replicates with 17 broiler chickens each, and the analyses were triplicated. The studied parameters were production performance, antioxidant status, hematological measurements, cellular and humoral immune response, intestinal acidosis, intestinal microbial counts, and volatile fatty acid (VFA) level in the hindgut. Results showed that broiler chickens fed 0.7% of FOS had significantly higher body weight gain than the control group and the groups fed 0.3% and 0.5% of FOS. Supplementing broiler feed with FOS at all levels increased the total antioxidant capacity (TAC) and reduced the malondialdehyde of the sera (P = 0.015 and 0.025, respectively). Liver catalase enzyme in the broiler chickens fed 0.5 and 0.7% of FOS was higher than that of the control group and the group fed 0.3% of FOS (P = 0.001). However, the liver MDA of the control group was higher than that of all the other groups (P = 0.031). The total WBC and heterophils % were the highest after supplementing broilers with 0.7% FOS (P = 0.004 and 0.003, respectively) at 3 wks of age. Conversely, lymphocytes and monocytes were the lowest for the 0.7% FOS group (P = 0.030 and 0.020, respectively). Dietary 0.05 and 0.7% of FOS induced the highest cellular response compared to the other treatments (P = 0.020). Thymus, bursa of Fabricious, and spleen weights were enhanced after FOS supplementation, which indicates a higher specific cellular response. To conclude, FOS prebiotic at all levels can be utilized safely to enhance the antioxidant activity and the cellular immune response of broiler chickens. Using 0.7% of FOS resulted in higher body weight of broilers. Accordingly, this amount of FOS is sufficient to reach the required results.

Effect of Ginger Powder on Production Performance, Antioxidant Status, Hematological Parameters, Digestibility, and Plasma Cholesterol Content in Broiler Chickens

The effect of dietary ginger powder on the production performance, digestibility, hematological parameters, antioxidant status, dietary oxidation stability, and plasma cholesterol content of broiler chickens was investigated. Ginger powder was included in the diet at 0, 5, 10, or 15 g/kg. Total antioxidant capacity and malondialdehyde in sera samples, superoxide dismutase activity, glutathione peroxidase, catalase, and malondialdehyde in liver samples, and the peroxide value and acid value of the stored diets were evaluated. The results showed that ginger inclusion significantly improved antioxidation indices in broiler sera and liver. Total body weight gain in ginger-supplemented birds was higher than that of control birds (p < 0.048). Supplementing the broiler chickens with ginger powder reduced total feed consumption (p < 0.031). White blood cell counts and the percentage of heterophils in the blood were increased in birds that received ginger supplementation (p < 0.001). The inclusion of ginger in the diet improved dry matter digestibility, crude protein utilization, crude fiber utilization, and ether extract utilization. In addition, blood cholesterol, triglyceride, and very low-density lipoprotein levels were decreased (p < 0.001), and high-density lipoprotein and levels were increased, following the inclusion of ginger in the diet (p < 0.001).