Use of liquorice ( Glycyrrhiza glabra ) in poultry nutrition: Global impacts on performance, carcass and meat quality

Licorice Extract Supplementation Benefits Growth Performance, Blood Biochemistry and Hormones, Immune Antioxidant Status, Hindgut Fecal Microbial Community, and Metabolism in Beef Cattle

This study aimed to evaluate the effects of licorice extract (LE) on growth performance, nutrient apparent digestibility, serum index (biochemistry, hormones, humoral immunity, and antioxidant function), hindgut fecal microbiota, and metabolism in beef cattle. In total, 12 male yellow cattle aged 12 months were divided into two groups (6 cattle per group): the basal diet (CK group) and the basal diet supplemented with 2 g/kg LE (CHM group). The entire experimental phase lasted for 120 days, including a 30-day pre-feeding period. Compared to the CK group, the average daily gain, crude fiber, calcium, and crude protein nutrient digestibility were greater on d 30 than d 60 (p < 0.05) and the feed meat ratio was lower for LE addition (p < 0.01). In terms of serum indexes, the insulin and nitric oxide contents were enhanced on d 30, the alkaline phosphatase level was improved on d 60, and the levels of albumin, immunoglobulin A, and catalase were increased on d 90 (p < 0.05). In contrast, the cholesterol content was lower on d 60 for LE addition compared with the CK group (p < 0.05). The higher enrichment of [Eubacterium]-oxidoreducens-group, p-2534-18b5-gut-group, and Ileibacterium were observed in the CHM group (p < 0.05), while the relative abundances of Gallibacterium and Breznakia in the CHM group were lower compared with the CK group (p < 0.05). In addition, the differential metabolites related to healthy growth in the CHM group were increased compared with the CK group. And there was a close correlation between hindgut microbiota and metabolic differentials. In general, LE has a promoting effect on the growth performance and health status of beef cattle over a period (30 to 60 days).

The efficacy of licorice root extract on meat amino acid, fatty acid, vitamin, and mineral composition and productivity of quail

Background and Aim

Poultry meat is an excellent animal protein source accessible to many low-income families in developing countries. It is also part of a balanced diet and contains valuable nutrients necessary for maintaining human health. The poultry sector implements improved processes to increase the quality and nutritional value of poultry meat. This study aimed to determine the influence of licorice root extract on the amino acid, fatty acid, vitamin, mineral composition, nutritional value, and productivity of quail meat.

Materials and Methods

Two groups were formed from Japanese quails: A control group and one experimental group, each consisting of 50 individuals. Quails from both the experimental and control groups received the same complete diet. Quails in the experimental group had licorice root extract added to their water at a dosage of 10 g/L, starting from the age of 3 days to 42 days of growth. At 42 days of age, 30 birds from each group were slaughtered to examine their meat productivity and chemical composition. The quail carcasses were analyzed for the following parameters: Live weight, carcass weight, nutritional value, mineral substances, vitamin content, fatty acid composition, amino acid composition, and amino acid score.

Results

This study demonstrated that quails in the experimental group receiving water with licorice extract exhibited higher indicators than those in the control group. Calcium (21.05%), magnesium (20.83%), and phosphorus (23.53%) were the most elevated mineral substances in the meat of the experimental birds. Vitamins E (22.22%) and C (20.0%) showed the greatest increase in vitamin content. The fatty acid composition parameters 17:0 margaric acid (8.16%), 18:3 linolenic acid (6.25%), and 20:4 arachidonic acid (4.49%) showed the highest increase. There was a clear increase in the amino acids valine (4.61%), lysine (4.32%), threonine (5.99%), tryptophan (4.87%), phenylalanine (5.87%), and cysteine (14.17%). The application of licorice root extract also positively impacted the amino acid score of quail meat, except for leucine, which remained within the range compared with the control group. Quails in the experimental group weighed 7.96% more live weight before slaughter than the controls. Moreover, the carcass weight was in favor of the experimental group (8.59%).

Conclusion

The use of licorice root extract positively influences the quality and biological value of quail meat. Data on amino acids, fatty acids, vitamins, trace elements, and other important components of quail meat will significantly expand our understanding of the biological value of licorice root extract. These findings can be used in the formulation of balanced diets for children and adults and highlight the importance of this issue.

Effects of dietary supplement with licorice and rutin mixture on production performance, egg quality, antioxidant capacity, and gut microbiota in quails (Turnix tanki)

This study was conducted to evaluate the effect of licorice and rutin on production performance, egg quality, and mucosa antioxidant levels in Chinese yellow quail. A total of 240 Chinese Yellow Quail (400-day-old) were randomly distributed into 5 groups: the Control group, fed with a basic diet; the LR1 group, fed with basal diet supplemented with 300 + 100 mg licorice and rutin mixture/kg diet; the LR2 group, fed with basal diet supplemented with 300 + 200 mg licorice and rutin mixture/kg diet; the LR3 group, fed with basal diet supplemented with 600 + 100 mg licorice and rutin mixture/kg diet and the LR4 group, fed with basal diet supplemented with 600 + 200 mg licorice and rutin mixture/kg diet. Compared with the control, supplementation with the licorice and rutin mixture improved the laying rate and eggshell thickness whereas decreased the feed conversion ratio of quails. Moreover, dietary supplementation with the licorice and rutin mixture improved the antioxidant capacity by increasing the activity of the superoxide dismutase (SOD) level and decreasing the concentration of malondialdehyde (MDA) in the jejunal mucosa. The licorice and rutin mixture altered the composition of intestinal microbiota by influencing the relative abundances of Bacteroidetes and Bacteroides. The relative abundances of the Bacteroidetes were significantly related to the laying rate of quails. In addition, the mixture of licorice and rutin was also effective in reducing the relative abundance of intestinal Proteobacteria and Enterobacter in quails, reducing the accumulation of antibiotic-resistance genes. The results revealed that supplementation of licorice and rutin mixture to the diet improved production performance, egg quality, and antioxidant capacity and modified the composition of intestinal microbiota in quails. This study provides a reference for Chinese herbal additives to promote production performance by modulating quail gut microbes.

The use of Astragalus membranaceus as an eco-friendly alternative for antibiotics in diets of Japanese quail breeders

Mature Japanese quails (n. 180), aged 8 wk, were divided into 6 groups to evaluate the influence of dietary Astragalus membranaceus powder on laying and reproductive performances, quality of egg, and blood metabolites. A completely randomized design experiment was performed including 6 groups. The first group of quails was served as control (basal diet). While, the 2nd, 3rd, 4th, 5th, and 6th group of quails fed a basal diet supplemented with 1, 2, 3, 4, and 5 g of AM powder/kg diet, respectively. Egg number (EN), weight (EW), and mass (EM) were not significantly influenced by dietary Astragalus membranaceus at all tested levels. The hatchability percentage was quadratically improved by dietary supplementation of A. membranaceus. Dietary supplementation of A. membranaceus positively affects (linear and quadratic) liver and kidney functions. Plasma total cholesterol (TC; P < 0.001) and Triglyceride (TG; P < 0.001) were linearly and quadratically decreased by dietary A. membranaceus increasing level. Blood urea level decreased with increasing A. membranaceus levels in the quail diet. The immunoglobulin G (IgG) and M (IgM) were higher than the control at all A. membranaceus levels. In conclusion, feeding quail breeders with Astragalus membranaceus at 1 g/kg diet has beneficial effects on feed conversion ratio; on production at 2 g/kg diet; on hatchability and immunity at 5 g/kg diet; and on total cholesterol at 3 g/kg diet and on shell quality at 4 g/kg diet. A. membranaceus products are expected to be novel valuable dietary supplements for poultry production, depending on the target trait.

Efficacy of licorice extract on the growth performance, carcass characteristics, blood indices and antioxidants capacity in broilers

Some studies have suggested that dietary medicinal plants or herbs may have a variety of biological functions such as anti-inflammatory, antiallergic, antifungal, antioxidative stress, and anticarcinogenic activities. The present study was undertaken to assess the incorporation of the extract of licorice supplementation on the growth performance, carcass yield, blood indices, and antioxidative capacity in broilers. Three hundred twenty unsexed one-day-old Ross 308 broiler chicks were allocated randomly into four groups. Chicks in each group were randomly subdivided into eight replicates of ten chicks. The first group received a basal diet and was considered a control. The respective groups received a basal diet supplemented with 1, 2, and 3 g licorice extract/kg diet. The obtained results indicated that supplementation of licorice extract to broiler chicks resulted in heavier BW and weight gain and a better feed conversion ratio during the experimental periods compared with the control group. However, feed consumption increased during the entire growing period. Supplementing the broiler's diet with licorice extract led to a higher value of erythrocytes, leukocytes, haemoglobin, plasma total protein, albumin, and antioxidant concentration and a low value in plasma cholesterol, triglycerides, uric acid, urea, and total cholesterol. It could be concluded that the dietary addition of licorice extracts 2 and 3 g licorice extract/kg diet improved broiler chicks' growth performance and physiological status.

Effects of in ovo injection of Astragalus kahericus polysaccharide on early growth, carcass weights and blood metabolites in broiler chickens

This study aimed to determine the impact of in ovo Astragalus kahericus polysaccharide (AKP) injections on performance, carcass weights, and blood constituents in Cobb chicks. Un-sexed 1 day broiler chicks (250) were divided into five treatment groups with five replicates of 10 chicks per group. The groups were as follows: (1) negative control (without additive), (2) positive control (saline injection), (3) 1.5 mg AKP, (4) 3.0 mg AKP, and (5) 4.5 mg in ovo AKP injections. Apart from the control groups, no significant changes in body weight at 3 and 5 weeks of age, and daily weight gains during 0-3 weeks of age were detected among the treatment groups. Daily feed consumption was decreased in AKP groups, while feed conversion ratio was improved with AKP when compared to the PC. AKP injections significantly altered the lipid profile parameters, including total cholesterol, triglycerides, low-density lipoproteins, and very low-density lipoproteins in the plasma (p < 0.05); but there were no statistical differences in HDL (p > 0.001). AKP injections significantly impacted biochemical blood parameters, including total protein, albumin, and globulin, in broiler chicken plasma (p < 0.05). Liver and kidney functions were influenced by in ovo AKP injections in broilers. Antioxidant enzymes also changed significantly after in ovo injection with AKP. Moreover, in ovo injection of AKP significantly altered immunity (IgG and IgM) in broilers. In conclusion, in ovo injection of AKP significantly improved liver and kidney functions, antioxidant activity, and immune function in broilers.

Licorice (Glycyrrhiza glabra L.)-Derived Phytochemicals Target Multiple Signaling Pathways to Confer Oncopreventive and Oncotherapeutic Effects

Cancer is a highly lethal disease, and its incidence has rapidly increased worldwide over the past few decades. Although chemotherapeutics and surgery are widely used in clinical settings, they are often insufficient to provide the cure for cancer patients. Hence, more effective treatment options are highly needed. Although licorice has been used as a medicinal herb since ancient times, the knowledge about molecular mechanisms behind its diverse bioactivities is still rather new. In this review article, different anticancer properties (antiproliferative, antiangiogenic, antimetastatic, antioxidant, and anti-inflammatory effects) of various bioactive constituents of licorice (Glycyrrhiza glabra L.) are thoroughly described. Multiple licorice constituents have been shown to bind to and inhibit the activities of various cellular targets, including B-cell lymphoma 2, cyclin-dependent kinase 2, phosphatidylinositol 3-kinase, c-Jun N-terminal kinases, mammalian target of rapamycin, nuclear factor-κB, signal transducer and activator of transcription 3, vascular endothelial growth factor, and matrix metalloproteinase-3, resulting in reduced carcinogenesis in several in vitro and in vivo models with no evident toxicity. Emerging evidence is bringing forth licorice as an anticancer agent as well as bottlenecks in its potential clinical application. It is expected that overcoming toxicity-related obstacles by using novel nanotechnological methods might importantly facilitate the use of anticancer properties of licorice-derived phytochemicals in the future. Therefore, anticancer studies with licorice components must be continued. Overall, licorice could be a natural alternative to the present medication for eradicating new emergent illnesses while having just minor side effects.

Use of Cinnamon and its Derivatives in Poultry Nutrition

The recent trend toward banning the use of antibiotics in poultry feed as a growth promoter directs the scientific community to look for natural alternatives with potential growth-promoting and immunomodulating properties. Phytogenic feed additives have attracted significant attention as alternatives to antibiotics to improve growth performance and enhance immune responses. They have anti-inflammatory, antioxidant, antiviral, and antifungal properties, depending on their chemical structure and composition. Scientists are using these non-conventional ingredients as feed additives in the form of oil or powder. Essential oils (EO) are volatile liquids produced from aromatic plants. Their application has gained momentum in controlling cholesterol as free radical scavengers, anti-microbials, antifungals, and stimulants of digestive enzymes. EO's possible antimicrobial features against harmful pathogens are primarily associated with the high content of volatile components in oils. The current chapter highlights the beneficial impact of cinnamon oil as a feed additive on poultry growth performance, meat quality, carcass traits, and its hypo-cholesterolaemic impact, antioxidant act, microbiological aspects, and immunomodulatory effects.

Effects of Compound Polysaccharides Derived from Astragalus and Glycyrrhiza on Growth Performance, Meat Quality and Antioxidant Function of Broilers Based on Serum Metabolomics and Cecal Microbiota

This study aimed to evaluate the effects of dietary supplementation of compound polysaccharides derived from Astragalus and Glycyrrhiza on growth performance, meat quality, antioxidant function, cecal microbiota and serum metabolomics of broilers. A total of 480 one-day-old male Arbor Acres (AA) broilers were randomly divided into four treatments with six replicates comprising 20 broilers each. Treatments: CON group was the basal diet; ANT group was supplemented with Terramycin calcium; LAG group was supplemented with 150 mg/kg Astragalus polysaccharides and 75 mg/kg Glycyrrhiza polysaccharides; HAG group was supplemented with 300 mg/kg Astragalus polysaccharides and 150 mg/kg Glycyrrhiza polysaccharides. The results showed that LAG and HAG supplementation increased growth performance, antioxidant function and meat quality compared with the CON group and ANT group and, especially, the effect of LAG treatment was better than HAG. Analysis of cecal microbiota showed that LAG and HAG supplementation altered cecal microbial diversity and composition in broilers. Serum metabolomics analysis showed that a total of 193 differential metabolites were identified in CON and LAG groups, which were mainly enriched in linoleic acid metabolism and glutathione metabolism pathways. Moreover, there was a close correlation between serum metabolites, cecal microbiota and phenotypic indicators. Conclusion: Dietary supplementation of 150 mg/kg Astragalus polysaccharides and 75 mg/kg Glycyrrhiza polysaccharides could improve the growth performance, antioxidant function and meat quality of broilers by changing the serum metabolites and cecal microbiota composition.

Licorice Extract Supplementation Affects Antioxidant Activity, Growth-Related Genes, Lipid Metabolism, and Immune Markers in Broiler Chickens

The objective of this study was to evaluate the Glycyrrhiza glabra effect on growth performance, blood parameters, antioxidant and lysosomal activity, histology and immunohistochemistry of liver and intestine, and the gene expression profile of broiler chickens. A total of 180 Cobb500 broiler chicks (one-week-old) were used in this study. Chicks were distributed randomly into three treatment groups; the first group received drinking water without any supplementation (control group). In contrast, birds in groups 2 and 3 received licorice supplementation in drinking water with 0.4 and 0.8 g licorice/liter, respectively. Results revealed that licorice at a 0.4 g/L of water level improved body weight, weight gain, feed intake, and FCR. Licorice also exhibits a broad range of biological activities such as hypolipidemic, hypoglycemic, hepatoprotective, immunostimulant, and antioxidant effects. The morphometric analysis of different parameters of the intestine revealed a significant increase in the intestinal villi length, width, and villi length/crypt depth in the group supplemented with licorice 0.4 gm/L compared to other groups. The number of CD3 positive in both duodenum and ileum was increased in the licorice 0.4 gm/L group compared to other groups. The expression of growth-related genes was significantly increased with licorice supplementation and modulation of the lipid metabolism genes in the liver and upregulated to the mRNA expression of both superoxide dismutase (SOD1) and Catalase (CAT). Our results revealed that licorice supplementation increased the growth performance of broiler chickens and impacted the birds' antioxidant activity through modulation of the growth-related genes, lipid metabolic markers, and antioxidant-related pathways.

Herbal Plants Application in Organic Poultry Nutrition and Production

Background:

Medicinal plants and natural feed additives are the most important alternatives in animal production, especially broiler production, due to the ban on the use of certain antibiotics, their cost-effectiveness and harmful residual effects.

Objective:

In this mini-review article, some important medicinal herbs and plants with positive effects on organic broiler production have been highlighted.

Methods:

A literature search was conducted in Science Direct, Google, Google Scholar, Springer, Medline and PubMed.

Results:

Medicinal plants such as ginger, ginkgo, thyme, ponderosa pine, soybean, forsythia, peppermint, Chinese star anise, astragalus, mistletoe, schisandra, cumin, capsicum, garlic, hooker chives, artichoke, Borreria latifolia, zataria, pomegranate, turmeric, lingzhi, Lippia javanica, neem, oriental chaff flower, mulberry leaf, goji berry, Aloe vera, pumpkin, grape, common nettle, marigold, coriandrum, Citrus sinensis, Alisma canaliculatum, Persian hogweed, Eucommiaulmoides, bamboo leaf extract, rosemary, Morina citrifolia, chestnut, green tea, wild mint, clove, sumac, satureja, ashwagandha, Lonicera japonica, Acacia, liquorice, Artemisia annua, milk thistle, cinnamon, black cumin and etc. have positive effects on organic broiler production.

Conclusion:

Herbal medicines lead to increased body weight due to a higher feed intake and a higher feed conversion ratio, and improve antioxidant activity of broiler chickens based on their phenolic compound contents. The combination of medicinal herbal additives also has a positive impact on broiler production. In organic broiler production with the usage of herbal plants, reducing hormones, growth promoters and antibiotics should be organized as well as considering appropriate organic feed management and higher production.

Influences of Dietary Supplementation with Maca (Lepidium meyenii) on Performance, Parameters of Growth Curve and Carcass Characteristics in Japanese Quail

Simple Summary

It is known that the bioactive compounds (N-benzyl-palmitamide, benzyl isothiocyanate, glucosinolates and phenolics) in the maca plant are appetizing, as well as having antioxidant effects and improving reproductive ability. The aim of this study was to determine the effects of adding maca plant powder to the ration at different levels on growth, slaughter carcass, partial egg production and some reproductive characteristics of Japanese quail (Coturnix coturnix japonica). Addition of maca powder to the diet increased the feed consumption but did not affect growth, slaughter carcass, partial egg production or fertility. In addition, maca powder reduced embryonic deaths and improved chick quality. According to these results, the positive effects of short-term application of maca powder are not observed during the fattening period in Japanese quails.

Abstract

Maca plant contains rich nutrients and in addition, it has various bioactive substances (N-benzyl-palmitamide, benzyl isothiocyanate, glucosinolates and phenolics). It is used to improve reproductive properties and has antioxidant effects for both humans and animals. The aim of this study was to determine the effects of adding maca plant powder to the ration at different levels on growth, slaughter carcass, partial egg production and some reproductive characteristics in Japanese quail (Coturnix coturnix japonica). The experimental groups were formed by adding 0% (control), 0.05% and 0.1% maca powder to the diet, and a total of 300 birds were used. Growth (weekly body weights, parameters of Gompertz growth function), feed efficiency and carcass characteristics of quails in the 42-day fattening trial were determined. Reproductive characteristics were measured up to 22 weeks of age. Addition of maca powder to the diet increased the feed consumption (p < 0.05) but did not affect body weights at 35 and 42 days of age, β₀ and β₁ parameters or point of inflection weight of the Gompertz model, carcass traits, partial egg production or fertility. It may be advisable to add 0.1% maca powder to the diets of breeders. Besides, maca powder reduced embryonic deaths and improved chick quality (both p < 0.05). It is thought that different results for reproductive traits can be obtained if maca powder is used for a longer period in the diets of breeder quail flocks.

Early nutrition programming with Astragalus membranaceus polysaccharide: its effect on growth, carcasses, immunity, antioxidants, lipid profile and liver and kidney functions in broiler chickens

This study aimed to determine the influence of in ovo injection of Astragalus membranaceus polysaccharide on growth, feed consumption, feed conversion ratio, carcasses, hematology, and blood metabolites in Cobb 500 chicks. At the 7th day of incubation, a total of 250 eggs were randomly divided into five groups with 5 replications of 10 eggs of each: negative control (normal eggs), positive control (0.5 mL saline), 1.5 mg Astragalus membranaceus, 3.0 mg Astragalus membranaceus, and 4.5 mg in ovo Astragalus membranaceus injection. Live body weight and gain were not significantly (linear and quadratic) affected by in ovo injection of Astragalus membranaceus. Kidney and liver functions were influenced by in ovo injection of Astragalus membranaceus polysaccharides in broiler chickens. Antioxidant enzymes were quadratically increased with Astragalus membranaceus polysaccharides, and the highest values achieved with 4.5 mg. The MDA concentration was linearly and quadratically decreased with in ovo injection of Astragalus membranaceus polysaccharides when compared to negative control. The highest values of IgG and IgM were achieved with 1.5 mg Astragalus membranaceus polysaccharides when compared to all other groups. In conclusion, our results indicate that in ovo injection of Astragalus membranaceus polysaccharides 1.5-4.5 mg in broiler eggs significantly improved serum ALT, AST, AP, creatinine enzymes, antioxidant activity, and immune function.

Natural immunity boosters as therapeutic interventions in the era of COVID-19 pandemic

COVID-19, a pandemic caused by SARS-CoV2 has been spread all over the world and is responsible for serious fatalities. SARS-CoV2 is included in the family of β-coronavirus that affects pulmonary gas exchange and triggers cytokines storm. Vigorous inflammation, hyper-coagulation, a decrease in lymphocytic count and an increase in neutrophilic count are observed in the second week after the onset of disease. Fever, dry cough, sneezing, shortness of breath and respiratory distress are the symptoms of COVID-19. Different preventive measures are taken to prevent the attack of coronavirus amongst social distancing, vaccination, wearing gloves and face masks and the use of sanitizers plays pivotal role. People with weak immunity are more susceptible to the attack of coronavirus. Various natural immunity boosters are known for their immune boosting properties among them are vitamin C, D, and B complex, medicinal mushrooms, plant-based stuff and minerals play important role by increasing the beneficial flora of human body. All these natural immunity boosters improve the innate and adaptive immune response against coronavirus. Hence, we conclude that the use of natural immunity boosters prevents the attack of coronavirus and make a person stronger against the suspected attack of COVID-19 and/or other viral diseases.

Efficacy of in ovo delivered resveratrol (Trans 3, 4, 5-trihydroxystilbene) on growth, carcass weights, and blood metabolites of broiler chicks

This research aimed to determine the impact of in ovo resveratrol (RV) (Trans.3, 4, 5-trihydroxystilbene) injection on performance, carcass weights, and blood constituents in Cobb chicks. A total of 300 fertile broiler breeder eggs were divided into five treatments as 60 eggs in each group, with 6 replicates (10 eggs each). The groups were as follows: (1) negative control (without additive), (2) positive control (saline injection), (3) 1.5 mg RV, 4) 3.0 mg RV, and (5) 4.5 mg in ovo RV injections. Significant changes were found in the amount of forage consumed per day, and the feed conversion ratio between treatment groups. RV injection significantly altered the parameters of the complete lipid profile, including total cholesterol, triglycerides, low-density lipoproteins, and very low-density lipoproteins, in plasma. RV injection significantly affected blood biochemical parameters, including total protein, albumin, and globulin in broiler chicken plasma. Liver and kidney functions were influenced by the injection of RV eggs into broiler chickens. The antioxidant enzymes also changed significantly after RV injection. Moreover, in egg injection from RV the immunogenicity (IgG and IgM) in broiler chickens were significantly altered. In conclusion, in ovo injection with RV significantly improved liver and kidney functions, antioxidant activity, and immune function in Cobb broilers.

The use of some plant-derived products as effective alternatives to antibiotic growth promoters in organic poultry production: a review

Improving poultry production, increasing poultry immunity, and reducing the disease spreading can be achieved by adding various potentially valuable ingredients to the feed or drinking water of poultry flocks. Because of the emergence of antimicrobial resistance, antibiotic growth promoters (AGP) in animal nutrition were prohibited. Additionally, consumer preferences tend towards purchasing products from livestock raised without antibiotics. Therefore, there is a critical need to find effective growth promoter alternatives and treatment methods for common poultry diseases. Some spice plants play important roles in improving the taste, aroma, and color of human food and their positive effects on human and animal health. The current review aimed to provide a broader perspective on some spice crops which can be effective alternatives to antibiotics in organic poultry production. These spices were including Thymus vulgaris, Cichorium intybus, Coriandrum sativum, Aloe vera, Heracleum persicum, Curcuma longa, and Glycyrrhiza glabra.

Olive Oil: Nutritional Applications, Beneficial Health Aspects and its Prospective Application in Poultry Production

Plant polyphenols have promoting health features, including anti-mutagenic, anti-inflammatory, anti-thrombotic, anti-atherogenic, and anti-allergic effects. These polyphenols improve the immune system by affecting the white blood cell proliferation, as well as by the synthesis of cytokines and other factors, which contribute to immunological resistance. Olive trees are one of the most famous trees in the world. Whereas, olive olive oil and derivatives represent a large group of feeding resource for farm animals. In recent years, remarkable studies have been carried out to show the possible use of olive oil and derivatives for improvement of both animal performance and product quality. In vivo application of olive oil and its derived products has shown to maintain oxidative balance owing to its polyphenolic content. Consumption of extra virgin olive oil reduces the inflammation, limits the risk of liver damage, and prevents the progression of steatohepatitis through its potent antioxidant activities. Also, the monounsaturated fatty acids content of olive oil (particularly oleic acid), might have positive impacts on lipid peroxidation and hepatic protection. Therefore, this review article aims to highlight the nutritional applications and beneficial health aspects of olive oil and its effect on poultry production.

Glycyrrhiza Genus: Enlightening Phytochemical Components for Pharmacological and Health-Promoting Abilities

The Glycyrrhiza genus, generally well-known as licorice, is broadly used for food and medicinal purposes around the globe. The genus encompasses a rich pool of bioactive molecules including triterpene saponins (e.g., glycyrrhizin) and flavonoids (e.g., liquiritigenin, liquiritin). This genus is being increasingly exploited for its biological effects such as antioxidant, antibacterial, antifungal, anti-inflammatory, antiproliferative, and cytotoxic activities. The species Glycyrrhiza glabra L. and the compound glycyrrhizin (glycyrrhizic acid) have been studied immensely for their effect on humans. The efficacy of the compound has been reported to be significantly higher on viral hepatitis and immune deficiency syndrome. This review provides up-to-date data on the most widely investigated Glycyrrhiza species for food and medicinal purposes, with special emphasis on secondary metabolites' composition and bioactive effects.

Impacts of Supplementing Broiler Diets with Biological Curcumin, Zinc Nanoparticles and Bacillus licheniformis on Growth, Carcass Traits, Blood Indices, Meat Quality and Cecal Microbial Load

The current study aimed to investigate the influence of dietary zinc nanoparticles (ZnNPs), curcumin nanoparticles (CurNPs), and Bacillus licheniformis (Bl) on the growth, carcass, blood metabolites, and the count of some cecal microorganisms of Indian River (IR) broilers. Chicks were allotted into seven experimental groups: control group, 1st, 2nd and 3rd groups were given diets enriched with ZnNPs, CurNPs and Bl (3.0, 5.0 and 2.0 cm3/kg diet, respectively). The 4th, 5th and 6th groups were given diets supplemented with ZnNPs (3.0) + Bl (2.0) (ZP); ZnNPs (3.0) + CurNPs (5.0) (ZC) and ZnNPs (3.0) + CurNPs (5.0) + Bl (2.0) (ZCP) cm3/kg diet, respectively. The results revealed that ZnNPs and CurNPs exhibited a considerable antimicrobial activity against pathogenic bacteria and fungi. They also inhibited the growth of microbes in a range of 50-95 µg/mL. The diet supplemented with ZnNPs, CurNPs, and Bl increased the body weight compared to the control after five weeks of age. Additionally, values of daily feed intake increased in these groups; however, the feed conversion ratio decreased. All values of carcass traits were better than that of the control. The treatments led to decreased abdominal lipids compared to the control. The activity of liver enzymes and malondialdehyde (MDA) activity decreased in the treated groups. In a converse trend, the levels of oxidative enzymes, amylase, protease, lipase and immunoglobulin were higher than that of the control. Meat quality properties were improved and cecal microbial counts were decreased. In conclusion, the ZnNPs, CurNPs, and Bl improved the broiler's weights, carcass traits, meat quality traits, as well as some blood indices and cecal microbial load. Therefore, the inclusion of ZnNPs, CurNPs, or Bl is recommended for broiler feeding regimens to improve the performance and health status.

Synergistic effect of royal jelly in combination with glycerol and dimethyl sulfoxide on cryoprotection of Romanov ram sperm

Sperm fertility decreases significantly after freezing. Providing a suitable and useful diluent compound for freezing ram sperm can increase the efficiency of artificial insemination and consequently, the reproductive performance of sheep. Various biological properties such as antibacterial, anti-cancer, immunosuppressive, antioxidant and reproductive properties of royal jelly (RJ) are well known. The aim of this study was to investigate the possible synergistic effect of royal jelly in combination with glycerol and dimethyl sulfoxide (DMSO) in sperm cryopreservation extender of Romanov ram. The pooled semen samples from 5 Romanov rams were allocated into 3 experiments. The effect of 6% DMSO, 6% glycerol and a combination of 3% DMSO +3% glycerol co-supplemented with 1, 2 and 3% RJ was evaluated in 3 experiments. Samples were frozen by conventional slow freezing method and post-thaw parameters of total motility, progressive motility, plasma membrane integrity, DNA damage, apoptosis, enzyme activity of superoxide dismutase (SOD) and glutathione peroxidase (GPx), total antioxidant capacity (TAC) and malondialdehyde (MDA) were evaluated. The results showed that the percentage of motility, progressive motility, TAC, GPx, SOD and all sperm kinematic parameters except LIN in the group containing 2% RJ + 6% DMSO was higher than the control group (p < 0.05). Some parameters such as progressive motility, sperm membrane integrity, TAC, GPx, VAP, VCL, STR and SRT in the group containing 2% RJ + 6% DMSO were more than (p < 0.05) in the sperm group containing 1% RJ + 6% DMSO. MDA values in sperm groups containing 2% RJ + 6% DMSO were significantly (p < 0.05) lower than the sperm containing 1% royal jelly and the control group. In the sperm group containing 2% RJ + 6% glycerol, sperm membrane integrity, TAC, GPx, SOD, progressive motility and all sperm kinematic parameters except VAP were higher and MDA values and sperm abnormalities were lower than the control group (p < 0.05). The sperm group containing 1% RJ and 3% DMSO +3% glycerol had higher motility, progressive motility, membrane integrity, and all sperm kinematic parameters except VSL; and lower sperm abnormalities, DNA damage, apoptosis and MDA than the control group (p < 0.05). As a general conclusion of this study, the addition of 2% RJ + 3% DMSO and 3% glycerol to the freezing extender improved microscopic and biochemical ram sperm parameters after the freeze-thaw process. Hence, moderate concentrations of royal jelly (2%) are sufficient to protect sperm from freezing damage, and high (3%) and low (1%) concentrations do not have a good cryoprotective effect.

Dietary effect of licorice (Glycyrrhiza glabra) on quail performance, carcass, blood metabolites and intestinal microbiota

This study aimed to assess the impacts of licorice (Glycyrrhiza glabra) on the growth performance, carcass traits, intestinal microbiota, liver and kidney functions, immunity, oxidative status, and lipid profile of Japanese quails. A total of 200 one-week-old unsexed Japanese quails with an average initial body weight of 26.24 ± 0.2 g were randomly distributed into 5 equal groups of 40 birds and further subdivided into 5 replicates. The first (control) group was fed a diet without any licorice, while licorice powder was added at levels of 250, 500, 750, and 1000 mg per kg diet in the second, third, fourth, and fifth groups, respectively. At the age of 3 wk, the group of quail fed on a diet supplemented with 750 and 1000 mg licorice/kg of diet gained the highest body weight (BW) and daily body weight (DBW), while attaining the lowest feed conversion ratio (FCR) compared to other groups. Meanwhile, groups fed diets with licorice at levels of 0 and 250 mg/kg showed the highest feed intake. After the 5-wk feeding trial, the highest BW and DBW values, and the lowest FCR were recorded in the group fed with 750 mg licorice/kg diet. The different treatments produced no significant differences (P > 0.05) in quail carcass characteristics, including percentages of carcass, liver, gizzard, heart, giblets, and dressing. The blood of the group fed a 750 mg licorice diet had higher contents of total protein and GLOB, while its contents of A/G%, lactate dehydrogenase (LDH), total cholesterol, triglyceride (TG), and low density lipoprotein (LDL) were lower. Apart from the high level of licorice (1000 mg/kg), the MDA level was linearly and quadratically (P = 0.0413 and 0.001) decreased with different licorice groups, while superoxide dismutase (SOD), total antioxidant capacity (TAC), immunoglobulin G (IgG), and M (IgM) were quadratically increased when compared to the control group. Licorice supplementation resulted in marked reductions in the number of total bacteria, coliforms, E. coli, and Salmonella, compared to those in the control. In conclusion, the inclusion of licorice at levels of 750 and 1000 mg/kg into the diet of Japanese quail enhances the animal's performance, immunity, antioxidant capacity, and maintains a healthy gut microbiota.

Use of lemongrass essential oil as a feed additive in quail's nutrition: its effect on growth, carcass, blood biochemistry, antioxidant and immunological indices, digestive enzymes and intestinal microbiota

The present study was designed to assess the impact of dietary supplementation of lemongrass essential oil (LGEO) on growth performance, carcass traits, liver and kidney function, immunity, antioxidant indices and caecal microbiota of growing quail. A total of 200 Japanese quails at 1-week-old were haphazardly allotted to 5 groups of 40 chicks in five replicates (8 per replicate). The first group was the control group, while LGEO was added at levels of 150, 300, 450, and 600 mg/kg diet in the 2nd, 3rd, 4th and 5th groups, respectively. Dietary supplementation of LGEO (150, 300 and 450 mg/ kg diet) increased body weight at 3 and 5 wk of age, and increased body weight gain during all periods compared with the control group (P < 0.05). All levels of LGEO improved feed conversion ratio during the periods from 1 to 3 and 1 to 5 wk of age. During 3 to 5 wk, feed conversion ratio was improved in quails fed LGEO (300 and 450 mg/kg diet) compared with the control and other treatments. Carcass traits, plasma globulin, alanine aminotransferase, and urea values did not differ among the treatments (P > 0.05), but the activity of aspartate aminotransferase in the plasma was significantly decreased (P < 0.05) in LGEO-treated groups. The total protein and albumin values were significantly increased (P < 0.05) in quails fed levels of LGEO (except 600 mg/kg diet) compared with the control. The inclusion of LGEO in quail diets improved (P < 0.05) plasma lipid profile. The dietary supplementation of LGEO increased (linear and quadratic, P < 0.05) plasma immunoglobulins (IgM, IgG, and IgA) levels, lysozyme values and activities of superoxide dismutase, total antioxidant capacity, reduced glutathione and catalase compared with the control group. The caecal Coliform, E. coli and Salmonella were lowered (P < 0.0001) in the quails treated with all LGEO levels, but the total bacterial count and Lactobacillus count were increased with dietary supplementation of LGEO levels (300 and 450 mg/kg) compared with those in the control group. The activities of digestive enzymes were significantly higher in birds fed the diet supplemented with LGEO levels than those fed the control diet. In conclusion, dietary supplementation of LGEO can improve the performance, lipid profile, immunity and antioxidant indices and decline intestinal pathogens and thus boost the health status of growing quail.

The Effect of Administration of a Phytobiotic Containing Cinnamon Oil and Citric Acid on the Metabolism, Immunity, and Growth Performance of Broiler Chickens

Simple Summary

In poultry farming, additives are sought after to ensure the living needs of birds, improve the health of birds, and improve growth performance. Noticeably, more and more hopes for obtaining such effects are being placed in plant additives, called phytobiotics, which are safe as natural additives, both for the health of birds and for not leaving toxic residues in final products (meat and eggs). A valuable phytobiotic ingredient is cinnamon, used in the form of an oil or a powder, which is obtained from the bark or leaves of the cinnamon tree. Cinnamon oil can stimulate the appetite, increase the secretion of digestive enzymes, stimulate immunity, have anti-allergic and detoxifying properties, and also have a positive effect on reducing sugar levels in the body. It has antimicrobial properties that destroy the cell membranes of pathogens, and, thanks to its antioxidant properties, it accelerates wound healing and stimulates the functioning and regeneration of intestinal epithelial cells. It is also antiparasitic, especially against gastrointestinal parasites. Due to the number of valuable properties of cinnamon oil, it seems advisable to find the most favorable dosage and time of application of this component to the chickens’ water, that may cause intended effects such as improving the health of chickens and increasing the efficiency of their rearing.

Abstract

It was postulated that a phytobiotic preparation containing cinnamon oil and citric acid added to drinking water for chickens in a suitable amount and for a suitable time would beneficially modify the microbiota composition and morphology of the small intestine, thereby improving immunity and growth performance without inducing metabolic disorders. The aim of the study was to establish the dosage and time of administration of such a phytobiotic that would have the most beneficial effect on the intestinal histology and microbiota, production results, and immune and metabolic status of broiler chickens. The experiment was carried out on 980 one-day-old male chickens until the age of 42 days. The chickens were assigned to seven experimental groups of 140 birds each (seven replications of 20 individuals each). The control group (G-C) did not receive the phytobiotic. Groups CT-0.05, CT-0.1, and CT-0.25 received the phytobiotic in their drinking water in the amount of 0.05, 0.1, and 0.2 mL/L, respectively, at days 1–42 of life (continuous application, CT). The birds in groups PT-0.05, PT-0.5, and PT-0.25 received the phytobiotic in the same amounts, but only at days 1–7, 15–21, and 29–35 of life (periodic application, PT). Selected antioxidant and biochemical parameters were determined in the blood of the chickens, as well as parameters of immune status and redox status. The morphology of the intestinal epithelium, composition of the microbiome, and production parameters of chickens receiving the phytobiotic in their drinking water were determined as well. The addition of a phytobiotic containing cinnamon oil and citric acid to the drinking water of broiler chickens at a suitable dosage and for a suitable time can beneficially modify the microbiome composition and morphometry of the small intestine (total number of fungi p < 0.001, total number of aerobic bacteria p < 0.001; and total number of coliform bacteria p < 0.001 was decreased) improving the immunity and growth performance of the chickens (there occurred a villi lengthening p = 0.002 and crypts deepening p = 0.003). Among the three tested dosages (0.05, 0.1, and 0.25 mL/L of water) of the preparation containing cinnamon oil, the dosage of 0.25 mL/L of water administered for 42 days proved to be most beneficial. Chickens receiving the phytobiotic in the amount of 0.25 mL/L had better growth performance, which was linked to the beneficial effect of the preparation on the microbiome of the small intestine, metabolism (the HDL level p = 0.017 was increased; and a decreased level of total cholesterol (TC) p = 0.018 and nonesterified fatty acids (NEFA) p = 0.007, LDL p = 0.041, as well as triacylglycerols (TAG) p = 0.014), and immune (the level of lysozyme p = 0.041 was increased, as well as the percentage of phagocytic cells p = 0.034, phagocytosis index p = 0.038, and Ig-A level p = 0.031) and antioxidant system (the level of LOOH p < 0.001, MDA p = 0.002, and the activity of Catalase (CAT) p < 0.001 were decreased, but the level of ferric reducing ability of plasma (FRAP) p = 0.029, glutathione p = 0.045 and vitamin C p = 0.021 were increased).

Effect of cereal type and plant extract addition on the growth performance, intestinal morphology, caecal microflora, and gut barriers gene expression of broiler chickens

Feeding broiler chickens on diets based on cereal grains of high non-starch polysaccharides content such as wheat and barley can negatively impact their performance and gut health. Plant extracts can be used as a potential tool to alleviate these negative effects. The present study assessed the effects of dietary cereal type and the inclusion of a plant extract blend (PEB) on the growth performance, intestinal histomorphology, caecal microflora, and gene expression of selected biomarkers for gut integrity in broiler chickens in a 42-d experiment. Ross-308 male broilers were assigned into different dietary treatments and fed on two cereal types (corn- vs. wheat/barley-based) with/without added graded concentrations of a PEB (0, 250, 500, 1000, and 2000 mg/kg diet). There were no significant differences in the growth performance parameters, intestinal histomorphology, and caecal microflora due to the impact of dietary cereal type. However, lactobacilli count in the caecal microflora was increased in the group fed on a corn-based diet. The PEB supplementation especially at a level of 500 to 1000 mg/kg diet significantly increased the average BW and decreased the feed conversion ratio. It also increased the villi length of duodenum, jejunum, and ileum, decreased the duodenal crypt depth, and increased the villi length to crypt depth ratio in the duodenum, jejunum and ileum. Supplementation of the PEB decreased the total bacterial and coliform count and increased the lactobacilli count in a linear pattern. Gene expression of Occludin and Junction Adhesion Molecule was significantly increased in the PEB supplemented diets, whereby no influence was observed on mucin expression. In conclusion, supplementation of a PEB at levels of 500-1000 mg/kg can be used as a tool to improve broiler performance and gut health.

Probiotics in poultry feed: A comprehensive review

The use of antibiotics to maintain animal well-being, promote growth and improve efficiency has been practised for more than 50 years. However, as early as the 1950s, researchers identified concern on the development of resistant bacteria for the antibiotics streptomycin and tetracycline used in turkeys and broilers respectively. These findings laid the groundwork for agricultural officials to impose stricter regulatory parameters on the use of antibiotics in poultry feeds. Probiotics are live micro-organisms included in the diet of animals as feed additives or supplements. Commonly known as a direct-fed microbial, probiotics provide beneficial properties to the host, primarily through action in the gastrointestinal tract (GIT) of the animal. Supplementation of probiotics in the diet can improve animal health and performance, through contributions to gut health and nutrient use. For instance, supplementation of probiotics has been demonstrated to benefit farm animals in immune modulation, structural modulation and increased cytokine production, which positively affect the intestinal mucosal lining against pathogens. Bacillus subtilis has been a popular bacterium used within the industry and was shown to improve intestinal villus height. Increasing the villus height and structure of the crypts in the GIT allows for the improvement of nutrient digestion and absorption. Tight junctions maintain important defences against pathogenic bacteria and cellular homeostasis. Heat stress can be a major environmental challenge in the poultry industry. Heat stress causes the bird to fluctuate its internal core temperature beyond their comfort zone. To overcome such challenges, poultry will attempt to balance its heat production and dissipation through behavioural and physiological adaptation mechanisms.

Consequences of various housing systems and dietary supplementation of thymol, carvacrol, and euganol on performance, egg quality, blood chemistry, and antioxidant parameters

The present work was carried out to investigate the influences of housing system and dietary essential oils (EOs) supplementation to laying hens on the productive performance, egg quality, immunity, antioxidant parameters, and hematology. A factorial arrangement (2 × 4) was performed, including 2 housing systems and 4 different types of EOs (without EOs, thymol, carvacrol, and euganol) during the production stages (from 28–78 wk of age). Birds were randomly divided into 2 groups with each of 2,000 birds. The first group was moved to laying cages while the second group was a floor reared. Each group was randomly divided into 4 groups (5 replicates of 100 birds each): The first were considered as a control group, and the second, third, and fourth groups were treated with thymol, carvacrol, and euganol EO, respectively. The results showed that hens reared in cage system had higher egg weight (P < 0.05), egg production, egg mass, and feed intake and better feed conversion ratio (P < 0.001) than those reared in the floor system. Blood picture values (except white blood cells), phagocytic index, phagocytic activity, and blood chemistry parameters (except calcium, phosphorus, and urea values) of laying hens were not affected (P > 0.05) by housing system. The groups fed EOs showed a rapid improvement (P < 0.001) in the egg production%, egg weight, egg mass, and egg quality. Thymol group had the highest egg production (P < 0.001). Thymol and eugenol groups had the highest egg weight, egg mass, and egg quality (P < 0.001). The groups fed diets containing thymol or eugenol consumed lower feed and had better feed conversion ratio (P < 0.001) than the control group. Immunity indices (phagocytic activity [P < 0.05], avian influenza [AIH5 and AIH9], P < 0.001) were improved with the presence of EOs in the laying hen diet. These results strongly suggest that dietary EO supplementation could be a successful attempt to improve the productive performance, egg quality, and immunity of laying hens.

Cinnamon (Cinnamomum zeylanicum) Oil as a Potential Alternative to Antibiotics in Poultry

The removal of antibiotic growth promoters (AGPs) as feed additives in poultry nutrition from the market in many countries has compelled researchers to find unconventional and safe alternatives to AGPs. Probiotics, prebiotics, enzymes, organic acids, herbs, immune-stimulants and essential oils (EO) have been investigated as feed additives in poultry production. Cinnamon (Cinnamomum zeylanicum), one of the oldest medicinal plants and widely used around the world, can be used in poultry rations in the form of powder or essential oil. Essential oils produced from aromatic plants have become more interesting owing to their potential effects as hypocholesterolaemic agents, antioxidants, antimicrobials, antifungals and stimulants of digestive enzymes. The potential insecticidal and antimicrobial activities of EO against pathogens that cause spoilage in agriculture crops and human diseases might be attributed mainly to the high content of volatile components (mainly cinnamaldehyde, eugenol and carvacrol) in cinnamon oil. The present review focuses on the effects of cinnamon oil as a feed additive on poultry performance, carcass traits, meat quality, hypocholesterolaemic impact, antioxidant activity, immunity and microbiological aspects.

Effect of Dietary Supplementation of Biological Curcumin Nanoparticles on Growth and Carcass Traits, Antioxidant Status, Immunity and Caecal Microbiota of Japanese Quails

This study was planned to evaluate the impact of different nano-curcumin levels on the growth rate, carcass, blood chemistry and caecal microbes of growing quail. A total of 270 Japanese quails at one-week-old were distributed to six equal groups; each group consisted of 45 unsexed birds with five replications (nine quails each). The 1st group was fed a basal diet, whereas the 2nd, 3rd, 4th, 5th and 6th groups were fed diets containing nano-curcumin (0.1, 0.2, 0.3, 0.4 and 0.5 g/kg diet, respectively). Nano-curcumin levels significantly increased (p ≤ 0.0001) body weight at 3 weeks and 5 weeks of age. Body weight gain during 1-3, 3-5 and 1-5 weeks of age was significantly increased (p < 0.0001) in groups treated with nano-curcumin levels (except at 0.3 g/kg; 1-3 weeks) compared to control. During 1 to 5 weeks, feed intake was decreased (p < 0.0001) in birds receiving nano-curcumin (0.1, 0.3 and 0.4 g/kg) diets. The best values of feed conversion ratio were recorded for the 0.4 g nano-curcumin-treated group. Carcass traits were not affected Nano-curcumin levels. The inclusion of nano-curcumin (0.2, 0.3 or 0.5 g/kg) significantly increased serum TP (p = 0.0004), albumin (p = 0.0078) and globulin (p < 0.0001). Quails fed with nano-curcumin (0.2 g/kg) exhibited the highest SOD and GSH activities, serum IgG and IgM concentrations and complement values compared to control. The addition of any level of nano-curcumin in the quail diet also significantly improved the lipid profile. In conclusion, supplemental nano-curcumin had beneficial impacts on growth, lipid profile, blood constituents, antioxidant indices, and immunity of growing quail, as well as increasing counts of lactic acid bacteria and reducing pathogenic bacteria.

Effect of Sodium Butyrate on Intestinal Health of Poultry – A Review

Health of the intestine is one of the main reasons that affects the bird’s performance, and thus the economic yield in the poultry sector. Various studies have examined how to improve the intestinal health using dietary supplements, including organic acids such as sodium butyrate (SB). The efficacy of the dietary supplementation in poultry is often assessed using an important parameter such as intestinal integrity, which is often assessed as a measure of high villus height and the ratio of villus height to crypt depth, or count of goblet cell numbers. In broilers, the villus length and width were increased by the addition of dietary SB. Since, at day 21 and 42, the villus length was increased by 55 and 27%, and 39 and 18% for birds fed 0.5 and 1 g/kg, respectively, compared with the control diet. Furthermore, SB plays an important role in development of poultry intestinal epithelium. It can be employed by the intestinal epithelial cells as an energy source to stimulate their differentiation and proliferation, and to improve intestinal barrier function. SB is effective against acid intolerant species such as Salmonella, Clostridium perfringens and E. coli. In addition, use of butyric acid at 0.6% reduced the pH of gastrointestinal segments. For this, SB could be a potential alternative in maintaining the health of gastrointestinal tract and improving the productive performance of poultry. This review refers to the expanding horizons in the research on SB supplementation in poultry health and nutrition.

Useful impacts of royal jelly on reproductive sides, fertility rate and sperm traits of animals

Royal jelly (RJ) is one of the furthermost valuable curative products mentioned by natural medicine scientists due to its promising medical and nutritional purposes. It possesses many impacts, including antioxidants, antimicrobial, antitumor, anti-inflammatory and immunomodulatory functions in human and animal that benefit their health and welfare, resulting in its widespread use in medical and commercial products and healthy food. Recently, favourable functions of RJ on male fertility have been reported in different animals. According to earlier literatures, the level of RJ supplementation in animal diet ranged from 100 to 200 mg/kg. Oral exposure to RJ has been reported to have oestrogenic influences in the adult female rats. Also, RJ may be influential in improvement of pregnancy and lambing rates of ewes. Oral administration of RJ at 100 mg/kg diet before sexual maturity enhanced sexual behaviour and semen quality of male rabbits. Moreover, RJ administration (up to 400 mg/kg diet once weekly) for male rabbits exposed to heat stress can counteract "summer infertility" and improve physiological responses. Furthermore, supplementation of freezing extender media with 0.1 or 3% RJ had a protective influence on cryopreserved and chilled spermatozoa of buffalo and ram respectively. However, the high dose of RJ oral administration (800 mg/kg) by pubescent male rats for 1 month had an undesirable effect on the reproductive system; however, the somewhat unfavourable influences were mitigated by the discontinuation of the administration. This review shows the chemical composition, favourable applications and health benefits of RJ and its effects on reproductive aspects, semen quality and in vitro fertilization outcomes which are advantageous for scientists, researchers, nutritionists, physiologists, embryologists, pharmacists, veterinarians, pharmaceutical industries and animal's breeders.

Use of red pepper oil in quail diets and its effect on performance, carcass measurements, intestinal microbiota, antioxidant indices, immunity and blood constituents

Plant-derived additives are used to maintain the health and growth performance of livestock. The use of red pepper oil (RPO) has recently attracted considerable scientific interest mainly due to its potential benefits for animals and humans. The present study was conducted to evaluate the effect of dietary supplementation with RPO on growth performance, carcass measurements, antioxidant status and immunity of growing quails between 1 and 5 weeks of age. A total of 240 growing quails (1-week old) were distributed into 5 equal groups consisting of 48 birds (4 replicates of 12 birds each). The first group was fed a basal diet without RPO (0 g/kg diet), and the second, third, fourth and fifth groups received diets containing RPO (0.4, 0.8, 1.2, 1.6 g/kg diet, respectively). The experiment lasted for 5 weeks. At age of 5 weeks, quails were slaughtered for carcass examinations, microbiological analysis of intestine and to determine blood constituents. Data were statistically analyzed by one-way ANOVA. Quails fed with 0.8 g RPO/kg diet showed 12.14%, 14.4% and 15% improvement in live BW, body weight gain and feed conversion ratio, respectively, compared with the control group. Quails that received diets with 1.2 g RPO consumed more feed than the others during the total period (1 to 5 weeks). Plasma globulin levels were significantly decreased (P = 0.0102), but albumin/globulin ratio was significantly increased (P = 0.0009) in birds fed diets containing RPO (0.4 and 1.2 g/kg) compared with those in the control group. Activity of liver enzymes in the plasma was nonsignificantly decreased in quails supplemented with 0.8 g RPO/kg diet compared with those in the control group. Activities of antioxidant enzymes (glutathione and catalase) in the group fed on diets supplemented with RPO (0.8 g/kg) were significantly higher than those in the control group. The inclusion of RPO (0.8 g/kg diet) in quail diets improved (P < 0.05) plasma lipid profile and also decreased pH of the caecal content (P = 0.0280) compared with those in the control group. The caecal bacterial population, Salmonella spp., coliform and Escherichia coli, were lowered (P < 0.05) in the groups treated with RPO (0.8, 1.2 and 1.6 g/kg) compared with those in the control group. In conclusion, dietary supplementation of RPO (0.8 g/kg) can enhance the performance and antioxidant indices and decrease intestinal pathogens and thus improve the health status of Japanese quail.

Use of Licorice (Glycyrrhiza glabra) Herb as a Feed Additive in Poultry: Current Knowledge and Prospects

Simple Summary

The present review updates the current knowledge about the beneficial effect of licorice supplementation in poultry diets, particularly its positive effect on the treatment of high-prevalence diseases of the immune system, liver, and lungs.

Abstract

Supplementation of livestock and poultry diets with herbal plants containing bioactive components have shown promising reports as natural feed supplements. These additives are able to promote growth performance and improve feed efficiency, nutrient digestion, antioxidant status, immunological indices, and poultry health. Several studies have used complex herbal formulas with the partial inclusion of licorice. However, the individual use of licorice has been rarely reported. The major problem of the poultry industry is the epidemiological diseases, mainly confined to the respiratory, digestive, and immune systems. Licorice has certain bioactive components such as flavonoids and glycyrrhizin. The roots of this herb contain 1 to 9% glycyrrhizin, which has many pharmacological properties such as antioxidant, antiviral, anti-infective and anti-inflammatory properties. Licorice extracts (LE) have a positive effect on the treatment of high-prevalence diseases such as the immune system, liver, and lung diseases. Studies showed that adding LE to drinking water (0.1, 0.2, or 0.3 g/L) reduced serum total cholesterol (p < 0.05) of broiler chickens. Moreover, LE supplementation in poultry diets plays a significant role in their productive performance by enhancing organ development and stimulating digestion and appetite. Along with its growth-promoting effects, licorice has detoxifying, antioxidant, antimicrobial, anti-inflammatory, and other health benefits in poultry. This review describes the beneficial applications and recent aspects of the Glycyrrhiza glabra (licorice) herb, including its chemical composition and role in safeguarding poultry health.