Mohamed E. Abd El-Hack

Beneficial impacts of thymol essential oil on health and production of animals, fish and poultry: a review

Abstract The thymol is an herbal food additive used to improve performance indices, feed utilization, immune system, and preventing from infectious diseases. Feeding animal, fish and poultry with diets supplemented with medicinal plants containing effective compounds and natural antioxidants in thymol demonstrated valuable potential of thymol to enhance the productive and reproductive performances, nutrient bioavailability, immunity and general health of livestock as well as lowering the problems of different animal diseases, side effects of chemical drugs, syntactic materials and cancer. These properties may be attributed to thymol’s capability to work as antispasmodic, antioxidant, antimicrobial, immunomodulatory, anticancer and anti-inflammatory agent by suppressing harmful compounds/free radicals from interacting with cellular biological compounds, ability to alter the gut microbiota, and increasing digestion, absorption and metabolism of nutrients. This review illustrates the multiple beneficial applications and various aspects of thymol including its chemical structure and physical proprieties, metabolism and excretion, mechanisms of action, natural sources and practical applications in animal, fish and poultry nutrition for increasing production, immunity and safeguarding health.

Green tea (Camellia sinensis) and l-theanine: Medicinal values and beneficial applications in humans—A comprehensive review

Green tea (Camellia sinensis) is a famous herb, and its extract has been extensively used in traditional Chinese medicinal system. In this context, several studies have revealed its health benefits and medicinal potentialities for several ailments. With ever increasing scientific knowledge, search for safer, potential and novel type of health-related supplements quest, scientists are re-directing their research interests to explore natural resources i.e. medicinal herbs/plant derived compounds. Green tea consumption has gained a special attention and popularity in the modern era of changing lifestyle. The present review is aimed to extend the current knowledge by highlighting the importance and beneficial applications of green tea in humans for safeguarding various health issues. Herein, we have extensively reviewed, analyzed, and compiled salient information on green tea from the authentic published literature available in PubMed and other scientific databases. Scientific literature evidenced that owing to the bioactive constituents including caffeine, l-theanine, polyphenols/flavonoids and other potent molecules, green tea has many pharmacological and physiological functions. It possesses multi-beneficial applications in treating various disorders of humans. This review also provides in-depth insights on the medicinal values of green tea which will be useful for researchers, medical professionals, veterinarians, nutritionists, pharmacists and pharmaceutical industry. Future research emphasis and promotional avenues are needed to explore its potential therapeutic applications for designing appropriate pharmaceuticals, complementary medicines, and effective drugs as well as popularize and propagate its multidimensional health benefits.

Effect of low-protein diets with crystalline amino acid supplementation on egg production, blood parameters and nitrogen balance in laying Japanese quails

A total of 120 Japanese quails were randomly distributed into six dietary groups to evaluate the effect of low-crude protein (CP) diet supplemented with crystalline amino acids on productive and reproductive performance, blood parameters and nitrogen (N) balance. Treatments consisted of six different diets: a control diet (20% CP), a low-CP (16%) diet supplemented with threonine (Thr), valine (Val) and tryptophan (Trp), three low-CP diets supplemented with individual Thr, Val or Trp, and a low-CP diet supplemented with all aforementioned amino acids. None of the growth traits examined were influenced either by dietary treatments or by egg production (P > 0.05). The highest fertility percentages (88.2%) were observed in quails fed the low-CP diet without crystalline amino acids supplementation followed by low-CP diet supplemented with Val (86.2%), whereas the highest hatchability (from fertile eggs) percentage was observed in quails fed low-CP diet plus Trp. Egg shell percentages from quails fed the control diet were higher (P < 0.05) compared to other dietary treatments during the whole feeding period. Yolk percentage was decreased (P < 0.01) with the low-CP diet supplemented with amino acids. Blood protein and ammonia levels were decreased (P < 0.05) by reducing the dietary CP level or by supplementing amino acids to the low-CP diet. Reducing the CP level in the diet with amino acids supplementation in laying quails decreased the daily N excretion (P < 0.05). It is concluded that reducing the CP level in a diet supplemented with crystalline amino acids supports reproductive performance in quails, and is a valuable strategy for decreasing feeding cost and mitigating ammonia emission.

Use of acetylsalicylic acid as an allostatic modulator in the diets of growing Japanese quails exposed to heat stress

The purpose of this study was to investigate the effect of dietary acetylsalicylic acid (ASA) supplementation on performance, carcasses and some blood metabolites of growing quails exposed to heat stress. Three hundred sixty mix sexed Japanese quail chicks at 2 wk of age with average initial body weight of 77.4 g were randomly allotted to six dietary groups in a 3 × 2 factorial design with three dietary ASA doses (0, 0.5 and 1 g ASA/kg diet) and two ambient temperatures (one normal at 23 ± 2 °C and other high at 33 ± 2 °C). Body weight, daily body weight gain and feed consumption reduced in quails exposed to heat stress (33 °C) during 2-4 wk of age, but not during 4-6 wk of age and during total period (2-6 wk of age). Growth rate and feed utilization were not influenced by ASA supplementation or interaction between ASA supplementation and house temperature at all ages (P > 0.05). All carcass parameters were not affected (P > 0.05) by temperature or dietary ASA or their interactions except dressing percent was decreased (P = 0.025) by ASA. Plasma cholesterol and total lipid were affected by the interaction effect, which were elevated in birds exposed to high ambient temperature (P = 0.004 or 0.022) and ASA supplementation (P = 0.041 or P = 0.003). Glucose concentrations were also influenced by interaction effect, which increased due to ASA supplementation at normal temperature, but were not affected at high temperature. The effect of high ambient temperature or its interaction with ASA did not affect hepatic enzymes and thyroid hormones of growing quails. Diets supplemented with ASA (1000 mg/kg) decreased plasma contents of aspartate transaminase, triiodothyronine (T3) and thyroxin (T4) compared with the control. It is concluded that applications of ASA in quail diets are not suitable in mitigating the disturbances induced by heat stress in the most studied parameters.

Herbal immunomodulators, a remedial panacea for the designing and developing effective drugs and medicines: Current scenario and future prospects

BACKGROUND Constant exposure to various stressors, such as immune pressure, rapidly increasing population, deleterious changes in the ecosystem, climate change, infection with emerging and re-emerging pathogens, and fast-paced lifestyle, is a critical factor in the globally increasing incidences of immunocompromising health conditions, as well as stress. Synthetic chemotherapeutic agents, which are widely available in the commercial market, may be highly efficacious, but most are immunosuppressive and exert many side effects. METHODS Herein, we comprehensively reviewed current literature from various scientific databases such as Bentham Science, PubMed, Scopus, Elsevier, Springer, etc. The inclusion/exclusion criteria based on literature with high importance was adopted to analyze and compile salient information from the authentic bibliographic sources. RESULTS Undoubtedly, the pivotal characteristics of immunostimulants and immunomodulators in the maintenance of the health and productivity of humans, as well as animals, cannot be overlooked. Numerous herbs used in ethnoveterinary medicine can be successfully employed as adjuvant rehabilitators to negate the deleterious effects of chemotherapeutics. The sources of these medicinal remedies are part of long traditions in different regions of the world, such as Indian Ayurveda and Traditional Chinese Medicine, which have been developed through empirical experience. Traditional medicine employs a holistic approach to the prevention of disease, and traditional herbal medicines are a source of many components with a high therapeutic value that are used in modern allopathic medicine. Globally, many studies have been conducted on these herbs and have revealed unique active constituents that activate the innate immune system through the stimulation of macrophages and lymphocytes, and modulation of the cytokine profile, which leads to a state of alertness with a subsequent reduction in the incidence of infection. Immunomodulatory constituents with herbal origins are termed as phytochemicals, including flavonoids, glycosides, polysaccharides, terpenoids, essential oils, various bitters, and alkaloids; all these compounds exert vital, multidimensional effects. Efforts have focused on screening plant preparations to identify adjuvant immune properties; furthermore, several potent phytol adjuvants have been experimentally proven to downregulate inflammatory reactions in addition to enhance specific adaptive responses to vaccines. CONCLUSIONS In summary, this review summarizes the current status and future prospects regarding the immunomodulatory potential of various herbs and plants and their promising utility for designing and developing effective drugs and medicines in safeguarding the health of humans, animals, and poultry.

The vital roles of boron in animal health and production: A comprehensive review

Boron (B) has many beneficial functions in biological, metabolic and physiological processes for plants and animals. It plays a vital role in maintaining animal health and preventing nutritional disorders. Boron deficiency has been correlated with low immune function and high incidence of osteoporosis which increases mortality risk. Extraordinary boron level causes cell damage and toxicity in human and different animal species. In the past few years, attention has been paid to clear the pleiotropic effects of boron including activating of immune response, antioxidant detoxification activities, affecting bone metabolism, enhancing animal performance and modulating various body systems. Furthermore, the role of boron as anti-heat stress agent has been identified in plants and suggested in animals. Liver metabolism also shows significant alterations in dairy cows in response to the dietary supplementation of boron. Likewise, adding boron to animal feed enhances bone density, wound healing and embryonic development. Additionally, boron has a potential impact on the metabolism of numerous minerals and enzymes. In view of the information about boron benefits, high or low level boron merits the concern. As well, researches are required to do more in-depth investigations on boron influences, and to adjust its requirements in different animal species.

Influence of Graded Levels of l-Theanine Dietary Supplementation on Growth Performance, Carcass Traits, Meat Quality, Organs Histomorphometry, Blood Chemistry and Immune Response of Broiler Chickens

l-theanine is a water-soluble non-proteinous amino acid mainly found in green tea leaves. Despite the availability of abundant literature on green tea, studies on the use of l-theanine as a feed additive in animals, and especially broilers are limited. The objective of this study was, therefore, to evaluate the effect of different dietary levels of l-theanine on meat quality, growth performance, immune response, and blood metabolites in broilers. A total of 400 day-old broiler chicks were randomly divided into four treatment groups using a completely randomized design; C-control, basal diet; 100LT-basal diet + 100 mg l-theanine/kg diet; 200LT-basal diet + 200 mg l-theanine/kg diet; and 300LT-basal diet + 300 mg l-theanine/kg diet. Results revealed that the intermediate level of l-theanine (200 mg/kg diet) showed better results in terms of body weight gain (BWG), feed consumed (FC), and feed conversion ratio (FCR) as compared with the other supplemented groups and the control. The live weight eviscerated weight and gizzard weight were higher in all l-theanine levels as compared to those of the control group. Increased weight (p ≤ 0.05) of spleen and bursa were found in group 200LT (200 mg l-theanine/kg diet). Concerning meat color parameters, values for yellowness (b*), and redness (a*) were greater in l-theanine-supplemented groups than the control. Supplementing broiler diet with l-theanine reduced (p = 0.02) total serum cholesterol contents while increased HDL. Further analysis revealed lower relative serum cytokines (IL-2 and INF-γ) and reduced mRNA expression of TNF-α and IL-6 in thymus, and IFN-γ and IL-2 in spleen in the treated group. Moreover, supplementation with 200 mg/kg of l-theanine improved antioxidant status in blood by increasing SOD, GSH-Px, and relative CAT levels. It is concluded that the optimum supplementation level of l-theanine is 200 mg/kg of diet because it resulted in improved performance parameters in broilers. However, higher levels of l-theanine (300 mg/kg diet) may have deleterious effects on performance and health of broiler chickens.

The use of probiotics as eco-friendly alternatives for antibiotics in poultry nutrition

Antibiotics as growth promoters in poultry have been used for long time for improving feed efficiency and performance. Due to their various side-effects such as antibiotic resistance, destruction of beneficial bacteria in the gut, and dysbiosis, it is required to think about some alternatives. Probiotics are one of the options in this regard for improving poultry production. Probiotics are defined as “live microorganisms that, when administered in adequate amounts, confer a health benefit on the host.” They are available in various forms for use as feed additives. Probiotics as feed additives aid in proper digestion of feed hence make the nutrients available for faster growth. Immunity can also be improved by addition of probiotics to poultry diets. Moreover, probiotics aid in improving meat and egg quality traits. Various infectious diseases of poultry can be countered by use of probiotics in their feed. A proper selection of probiotic strains is required for gaining optimal effects. This review focuses on the mechanisms of action of probiotics and their importance in poultry feed supplementation for enhancing production and safeguarding health of poultry.

Yucca schidigera extract modulates the lead-induced oxidative damage, nephropathy and altered inflammatory response and glucose homeostasis in Japanese quails

The present study was conducted to explore the toxic effects of lead (Pb) on the physiological responses of Japanese quails and to investigate the potential modulatory role of Yucca schidigera extract (YSE) against these effects. 360 mature Japanese quails (at 2 months of age) were used and the experiment was lasted for 8 weeks. The birds were divided into six equal groups as follow: control (basal diet, BD), BD+Pb (100 mg/kg diet), BD+YSE (100 mg/kg diet), BD+YSE (200 mg/kg diet), BD+Pb (100 mg/kg diet) +YSE (100 mg/kg diet) and BD+ Pb (100 mg/kg diet) + YSE (200 mg/kg diet). Pb induced a significant reduction in superoxide dismutase (SOD) and catalase (CAT) activities and reduced glutathione (GSH) level. While, increased protein carbonyl (PC) and malondialdehyde (MDA) content in tissues of exposed birds. Pb increased level of 8-hydroxy-2-deoxyguanosine (8-OHdG) and lactate dehydrogenase (LDH) activity in serum. YSE significantly reduced the Pb -induced oxidative stress in co-treated groups especially at 200 mg/kg diet. YSE could modulate the Pb -induced decreased urea, creatinine and beta-2 microglobulin (B2M) levels. YSE200 was found to be better than the YSE100 in decreasing levels of inflammatory markers including tumor necrosis factor (TNF-α), nitric oxide (NO), transforming growth factor-β1 (TGF-β1) and vascular endothelial growth factor (VEGF). Furthermore, YSE significantly regulates glucose homeostasis in co-exposed quails. Pb residues were found to be significantly higher in kidney and pancreas tissues of Pb group compared to other groups. YES decreased the expression of metallothionein-1 in the renal and pancreatic tissues, while elevated insulin expression in the pancreatic cells by immunostaining in co-exposed groups. In conclusion, the present results conclusively demonstrate the potential modulatory effect of YSE against the Pb-induced toxic effects in different organs of Japanese quails.

Impacts of distiller’s dried grains with solubles as replacement of soybean meal plus vitamin E supplementation on production, egg quality and blood chemistry of laying hens

Abstract The present investigation aimed to study the effect of the partial replacement of distiller’s dried grains with solubles (DDGS) instead of soybean meal (SBM) with or without vitamin E supplementation in laying hen diet on egg quality criteria, egg analysis, blood chemistry and productive performance traits. A 4×2 factorial design experiment was carried out involving four substitution levels of DDGS (0, 25, 50 and 75%) and two levels of vitamin E (0 and 250 mg /kg diet) through 22-42 weeks of age. No significant differences were noticed between the control and 25 or 50% DDGS substitution in the percentage of eggs produced and egg output. The fewest number of produced eggs and the lightest egg output were observed in 75% DDGS group. Yolk index, shell percentage, and Haugh unit scores were affected (P>0.01) by DDGS levels. Albumin percentage showed increase (P>0.01) in vitamin E treated groups. The impact of the combination of DDGS and vitamin E was significant (P>0.01) on all egg quality traits excepting shell percentage. The 75% DDGS diet gave the highest values of egg nutrients. Vitamin E had a positive effect on egg crude protein, ether extract, and nitrogen free extract which increased by 10.39, 10.28 and 7.85%, respectively. The combination of vitamin E addition and DDGS levels was highly significant (P>0.01) on all egg nutrients. Hens fed the 50% DDGS diet had more concentrations of lipids profile in their blood than those fed control and other DDGS diets. All serum lipid profile inclined to increase due to vitamin E supplementation. The interaction between DDGS and vitamin E had significant (P>0.05 or 0.01) influence on all serum metabolites excepting calcium. It could be concluded that vitamin E could enhance nutrient content of eggs and preserve blood lipids from lipid peroxidation. The interaction between 75% DDGS replaced SBM with 200 mg vitamin E/kg diet accomplished the best results regarding nutrient content of eggs.