Validating the use of a newly developed cinnamaldehyde product in commercial broiler production

Essential oils (EOs) have been considered as an alternative to antibiotics for animal production. In the current study, 4 trials were conducted on a commercial broiler farm to investigate the effects of dietary supplementation of an encapsulated cinnamon EO product (NE-OFF) on the bird growth performance, gut health, and gene expression in the ileum, spleen, and liver relating to the host response to heat and other stresses, including potential NE challenge. In each trial, approximately 30,000 Cobb or Ross broilers were randomly allocated to 4 treatments: a raised without antibiotics (RWA) commercial diet as positive control, an adjusted RWA commercial diet as negative control, and the negative control diet supplemented with 2 different dosages of NE-OFF, which was added during feed pelleting. Although the final average body weight did not differ significantly among treatment groups, birds fed NE-OFF had an increased ratio of villus height and crypt depth in the jejunum, and reduced fecal oocyst counts. Trial 2 was conducted in the summer and had a necrotic enteritis (NE) outbreak. The supplementation of NE-OFF reduced the NE incidence and bird mortality. The samples from Trial 2 were hence selected for the analyses of Clostridium perfringens and NetB toxin gene abundance in the ileum, and host responses. The C. perfringens population appeared to be positively correlated with the NetB gene abundance. The gene expression analysis suggested that NE-OFF supplementation improved nutrient absorption and transportation as well as antioxidant activities to help the birds against stress. These on-farm trial results support the hypothesis that the use of NE-OFF as a feed additive can improve bird gut health and performance in commercial broiler production, especially for preventing NE outbreaks when birds are under stress.

Immunostimulant potential of Moringa Oleifera leaves alcoholic extract versus Oregano Essential Oil (OEO) against cyclophosphamide-induced immunosuppression in broilers chicks

The current study was conducted to evaluate the immunoenhancement effect of Moringa oleifera leaves alcoholic extract (MOLE) versus Oregano essential oil (OEO) against cyclophosphamide induced immunosuppression in broilers chicks. A total of a three hundred one-day-old chicks were assigned randomly into three main dietary groups, control, MOLE, and OEO for 14 days. After 14 days the three main experimental groups were subdivided into six groups, control, cyclophosphamide, MOLE, MOLE and Cyclophosphamide, OEO, and OEO and cyclophosphamide. Each group of these six groups was subdivided into three subgroups. Supplementation of broiler chicks with MOLE and OEO for 14 days significantly increased body weight compared to the control group. However, injection of broiler chicks with cyclophosphamide significantly induced body weight loss, impaired immunological response represented by decreasing total leukocytic count, differential leukocytic count, phagocytic activity, phagocytic index, and hemagglutinin inhibition titer for New Castle disease virus, lymphoid organs depletion, and increased the mortality rate. In contrast, supplementation of cyclophosphamide treated chicks with MOLE and OEO significantly reduced cyclophosphamide induced body weight loss and impaired immunological responses, as it showed significant increase in body weight, total leukocytic count, differential leukocytic count, phagocytic activity, phagocytic index, and hemagglutinin inhibition titer for New Castle disease virus, lymphoid organs proliferation, and reduced the mortality rate. This study indicated that MOLE and OEO supplementation ameliorated cyclophosphamide induced body weight loss and impaired immunological responses.

Effects of encapsulation methods on bioaccessibility of anthocyanins: a systematic review and meta-analysis

Anthocyanins have multiple health benefits. However, they are prone to degradation during gastrointestinal digestion, impeding their utilization. Various encapsulation systems have been proposed to improve their bioaccessibility and bioavailability. This review aims to provide a systematic evaluation and meta-analysis of published studies examining the effect of microencapsulation on the bioaccessibility of anthocyanins. A comprehensive and systematic literature search of three databases (Scopus, PubMed, and Web of Science) was conducted. Studies were selected according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria and were reviewed independently by two investigators. Overall, 34 articles were included in the systematic review and 24 were included in the meta-analysis. The fold changes in bioaccessibility between encapsulated and non-encapsulated anthocyanins from eligible studies were calculated. The median and 95% confidence intervals (CI) of the fold changes for spray-drying (median 1.23, 95% CI 0.91-1.92), freeze-drying (median 1.19, 95% CI 0.61-1.28), simple coacervation (median 1.80, 95% CI 1.41-3.20), and complex coacervation (median 1.61, 95% CI 0.21-25.00) were calculated. Simple coacervation showed a promising protection against degradation during in vitro digestion. However, when a large number of anthocyanins cannot be released from the microparticles during digestion, encapsulation impedes the bioaccessibility of anthocyanins.

Anti-Inflammatory and Antioxidative Phytogenic Substances against Secret Killers in Poultry: Current Status and Prospects

Chronic stress is recognized as a secret killer in poultry. It is associated with systemic inflammation due to cytokine release, dysbiosis, and the so-called leaky gut syndrome, which mainly results from oxidative stress reactions that damage the barrier function of the cells lining the gut wall. Poultry, especially the genetically selected broiler breeds, frequently suffer from these chronic stress symptoms when exposed to multiple stressors in their growing environments. Since oxidative stress reactions and inflammatory damages are multi-stage and long-term processes, overshooting immune reactions and their down-stream effects also negatively affect the animal's microbiota, and finally impair its performance and commercial value. Means to counteract oxidative stress in poultry and other animals are, therefore, highly welcome. Many phytogenic substances, including flavonoids and phenolic compounds, are known to exert anti-inflammatory and antioxidant effects. In this review, firstly, the main stressors in poultry, such as heat stress, mycotoxins, dysbiosis and diets that contain oxidized lipids that trigger oxidative stress and inflammation, are discussed, along with the key transcription factors involved in the related signal transduction pathways. Secondly, the most promising phytogenic substances and their current applications to ameliorate oxidative stress and inflammation in poultry are highlighted.

Essential oils as valuable feed additive: A narrative review of the state of knowledge about their beneficial health applications and enhancement of production performances in poultry

New research has begun to develop safe and effective alternatives to feed-antibiotics as growth enhancers in response to mounting pressure on the poultry sector to do so. There is a significant demand for poultry products all across the world right now. To achieve this goal, key performance indicators are optimized, such as the rate of chicken growth, the amount of feed used, and the health of the flock as a whole. As a result of this growing need, various alternatives to antibiotics have entered the market. New approaches are desperately needed to keep poultry productivity and efficiency at a high level in the face of mounting pressure to limit the use of antibiotics. Recent years have seen an uptick in interest in the potential of aromatic plant extracts as growth and health boosters in poultry. The great majority of plants' positive effects are accounted for by essential oils (EOs) and other secondary metabolites. EOs have been proven to promote digestive secretion production, improve blood circulation, exert antioxidant qualities, reduce levels of dangerous microbes, and maybe improve the immune status of poultry. EOs are often believed to be safe, non-toxic alternatives because they are all-natural, chemical-free, and devoid of potentially harmful deposits. EOs are extracted from plants, and while there are thousands of them, only approximately 300 have been deemed to have significant commercial value. Many different types of bacteria, viruses, fungi, and parasites are negatively affected by EOs in multiple studies conducted both in vitro and in vivo. The review covers the fundamentals of EOs, their anti-oxidant and immunomodulatory capabilities, their growth-promoting benefits, and their effectiveness against numerous diseases in poultry.

Citrus Essential Oils in Aromatherapy: Therapeutic Effects and Mechanisms

Citrus is one of the main fruit crops cultivated in tropical and subtropical regions worldwide. Approximately half (40-47%) of the fruit mass is inedible and discarded as waste after processing, which causes pollution to the environment. Essential oils (EOs) are aromatic compounds found in significant quantities in oil sacs or oil glands present in the leaves, flowers, and fruit peels (mainly the flavedo part). Citrus EO is a complex mixture of ~400 compounds and has been found to be useful in aromatic infusions for personal health care, perfumes, pharmaceuticals, color enhancers in foods and beverages, and aromatherapy. The citrus EOs possess a pleasant scent, and impart relaxing, calming, mood-uplifting, and cheer-enhancing effects. In aromatherapy, it is applied either in message oils or in diffusion sprays for homes and vehicle sittings. The diffusion creates a fresh feeling and enhances relaxation from stress and anxiety and helps uplifting mood and boosting emotional and physical energy. This review presents a comprehensive outlook on the composition, properties, characterization, and mechanism of action of the citrus EOs in various health-related issues, with a focus on its antioxidant properties.

Thymol and carvacrol supplementation in poultry health and performance

BACKGROUND

Thymol and carvacrol as natural essential oils and phenol compounds are components derived from some medicinal plants, such as thyme and oregano species.

OBJECTIVES

The increasing demands in organic and healthy meat and egg consumption in human society have made it necessary to consider alternative natural compounds for the replacement of chemical compounds in poultry production. The chemical compounds can remain in meat and eggs and cause complications in human health. Therefore, these natural compounds can be fed with a higher safety in poultry production with specific effects. In this regard, the role of thymol and carvacrol as natural compounds in the poultry production has been discussed in the review.

METHODS

In this study, by searching for keywords related to thymol and carvacrol in poultry production in Google Scholar database, the articles related to different aspects of the biological effects of these two phytogenes in poultry production were selected and analyzed.

RESULTS

A review of previous studies has shown that thymol and carvacrol possess a wide range of biological activities, including antibacterial, antiviral, antioxidant, anti-inflammatory, modulating of immunity response and regulating of the gut microbial population. Also, in meat type chickens can promote growth and influence feed utilization. The beneficial effect of this compound was evaluated in hepatic toxicity and demonstrated as a hepatoprotective compound in chickens. Furthermore, these compounds can affect the behavior of layers and influence egg composition, eggshell thickness, and the sensory quality of eggs.

CONCLUSION

It seems that with the increasing demand for healthy protein products, these compounds can be used to improve performance as a substitute alternative for chemical compounds in healthy poultry farms.

Free and Microencapsulated Essential Oils Incubated In Vitro: Ruminal Stability and Fermentation Parameters

Essential oils (EOs) are generally considered as an alternative to antibiotics because of their antimicrobial properties. Despite their vast variety, their volatile nature poses hindrance on their use in animal feeds, which demands a high degree of stability. This study aimed at testing the susceptibility of three EOs (mixtures of EOs based on cinnamaldehyde, named Olistat-Cyn, Olistat-G, and Olistat-P) in two forms (free: fEOs; and microencapsulated: mEOs) to in vitro ruminal degradation using the Ankom DaisyII technique. The microencapsulation was made using a matrix based on vegetable hydrogenated fatty acids. Compared to the fEOs, which were completely degraded within 48 h of in vitro incubation, the mEOs showed a low ruminal disappearance. In comparison to the fermentation profile at 0 h, Olistat-G significantly decreased the pH and the total protozoa number after 48 h, while the total VFAs increased. However, the other EOs (Olistat-Cyn and Olistat-P) had no effect on the rumen fermentation parameters. In conclusion, the protection of EOs from ruminal degradation by microencapsulation was found to be very effective to ensure rumen by-pass. Among the EOs, Olistat-G was capable of changing rumen fermentation, potentially reducing methane emissions.

Protective Effects of 1,8-Cineole Microcapsules Against Inflammation and Gut Microbiota Imbalance Associated Weight Loss Induced by Heat Stress in Broiler Chicken

Intestinal microbiota dysregulation is considered the primary trigger of low-grade inflammation responsible for weight loss due to heat stress. 1,8-Cineole is the major bacteriostatic agent in eucalypt and possesses remarkable anti-inflammatory properties. However, the mechanisms of its effect on intestinal microbiota remain unclear. In this study, 1,8-cineole was prepared into microcapsules prior to use as feed supplement in chickens. The microencapsulation efficiency and chemical stability of 1,8-cineole microcapsules were evaluated. The chicken treatment with 1,8-cineole microcapsules (1 or 3%) for 45 days, in the presence or absence of heat stress for fifteen days, commenced on Day 31, with or without an antibiotics mix (Abx) for three days on Day 27. Performance parameters were measured once a week from Day 30 through Day 45. Surface and entrapped concentration of 1,8-cineole was estimated as 7.89 g/100 g powder in the microcapsules. The time to maximal concentration (T_max), terminal half-life (T_1/2), and the area under plasma concentration-time curve (AUC_0-t) of the encapsulated 1,8-cineole were higher than those of the nonencapsulated in treated chickens, although the maximal concentrations (C_max) were similar. Chickens treated under higher temperatures with 1,8-cineole microcapsules exhibited lower levels of grade inflammation and higher body weight gain. Dietary 1,8-cineole microcapsules recovered the normal structure of upper ileum and altered the ratio of gut microbiota under heat stress and increased the ratio of Lactobacillus and Escherichia, whereas the proportion of Salmonella decreased based on 16S rRNA analysis of the upper ileum microbiota. In vitro, 1,8-cineole effectively inhibited the growth of Salmonella as demonstrated by inhibition zone assay. In summary, our findings elucidated the interaction between 1,8-cineole and intestinal microbiota as a new mechanism for the anti-heat stress effect of 1,8-cineole in preventing low-grade inflammation and weight loss. The results suggest that 1,8-cineole microcapsules may be a good feed supplement to protect against heat stress injury.

Dietary Application of Tannins as a Potential Mitigation Strategy for Current Challenges in Poultry Production: A Review

Simple Summary

There are diverse challenges in the poultry production industry that decrease the productivity and efficiency of poultry production, impair animal welfare, and pose issues to public health. Furthermore, the use of antibiotic growth promoters (AGP) in feed, which have been used to improve the growth performance and gut health of chickens, has been restricted in many countries. Tannins, polyphenolic compounds that precipitate proteins, are considered as alternatives for AGP in feed and provide solutions to mitigate challenges in poultry production due to their antimicrobial, antioxidant, anti-inflammatory and gut health promoting effects. However, because high dosages of tannins have antinutritional effects when fed to poultry, determining appropriate dosages of supplemental tannins is critical for their potential implementation as a solution for the challenges faced in poultry production.

Abstract

The poultry industry has an important role in producing sources of protein for the world, and the size of global poultry production continues to increase annually. However, the poultry industry is confronting diverse challenges including bacterial infection (salmonellosis), coccidiosis, oxidative stress, including that caused by heat stress, welfare issues such as food pad dermatitis (FPD) and nitrogen and greenhouse gasses emissions that cumulatively cause food safety issues, reduce the efficacy of poultry production, impair animal welfare, and induce environmental issues. Furthermore, restrictions on the use of AGP have exacerbated several of these negative effects. Tannins, polyphenolic compounds that possess a protein precipitation capacity, have been considered as antinutritional factors in the past because high dosages of tannins can decrease feed intake and negatively affect nutrient digestibility and absorption. However, tannins have been shown to have antimicrobial, antioxidant and anti-inflammatory properties, and as such, have gained interest as promising bioactive compounds to help alleviate the challenges of AGP removal in the poultry industry. In addition, the beneficial effects of tannins can be enhanced by several strategies including heat processing, combining tannins with other bioactive compounds, and encapsulation. As a result, supplementation of tannins alone or in conjunction with the above strategies could be an effective approach to decrease the need of AGP and otherwise improve poultry production efficiency.

Design of biopolymer carriers enriched with natural emulsifiers for improved controlled release of thyme essential oil

This work aims to characterize a novel system for thyme essential oil delivery based on the combination of natural emulsifiers (soy protein and soy lecithin) and alginate, produced using the extrusion technique. The formulations are optimized concerning alginate and soy protein concentrations (both 1 to 1.5 wt.%), and consequently lecithin amount, in order to achieve spherical beads in the range 2.0 to 2.3 mm and 1.2 to 1.4 mm, wet and dry, respectively. Fourier-transform infrared analysis was performed, proving that there are interactions between all components. Lecithin-soy protein synergistic combination improved entrapment efficiency of total polyphenols (for nearly 12%) and decreased thymol release in a simulated gastric solution for nearly 35%, in comparison with beads without lecithin. The addition of lecithin enhances the thermal properties of the polysaccharide-protein systems at 50 °C after 3 hr of heating. The mechanical stability of the biopolymer carriers is improved with lecithin addition and the elastic modulus varied from 80.06 to 123.7 kPa, depending on the formulation. Alginate/soy protein/lecithin are effective carriers for the encapsulation, protection, and controlled release of thyme essential oil. PRACTICAL APPLICATION: There is unfortunately growing human resistance to antibiotics. This work offers a novel system for effective protection and controlled release of thyme essential oil in the small intestine. The mechanical and thermal properties of the carrier were estimated as they indicate how the beads will be able to resist stress during their incorporation into food (i.e. cookies-mixing, baking). The proposed approach offers ''green advantage'' as arises from all-natural materials.

Natural Macromolecules as Carriers for Essential Oils: From Extraction to Biomedical Application

Essential oils (EOs) and their main constituents, the terpenes, are widely studied, mostly relating to their antioxidant ability and bioactivity, such as antimicrobial, anticancer, anti-inflammatory, and range of other actions in the living systems. However, there is limited information on their bioavailability, especially upon clinical studies. Having in mind both strong biological effects and health benefits of EOs and their specific physicochemical properties (volatility, lipophilic character, low water solubility or insolubility, viscosity, expressed odor, concentration-dependent toxicity, etc.), there is a need for their encapsulation for target delivery. Encapsulation of EOs and their constituents is the prerequisite for enhancing their oxidative stability, thermostability, photostability, shelf life, and biological activity. We considered various carrier types such a (1) monophase and polyphase polysaccharide hydrogel carriers, (2) polysaccharide-protein carriers, and (3) lipid carriers in the context of physicochemical and engineering factors. Physicochemical factors are encapsulation efficiency, chemical stability under gastric conditions, mechanical stability, and thermal stability of carrier matrices. Choice of carrier material also determines the encapsulation technique. Consequently, the engineering factors are related to the advantage and disadvantage of various encapsulation techniques frequently used in the literature. In addition, it was intended to address the interactions between (1) main carrier components, such as polysaccharides, proteins, and lipids themselves (in order to form chemically and mechanically stable structure); (2) main carrier components with pepsin under gastric conditions (in order to form resistant material under gastric conditions); and (3) main carrier components with EOs (in order to enhance encapsulation efficiency), as a necessary precondition for whole process optimization. Finally, different sources for obtaining natural carrier macromolecules are surveyed, especially the agro-waste materials and agricultural and food by-products. This review article highlights the bioavailability aspects of encapsulated EOs and physicochemical and engineering factors concerning natural macromolecule carriers for their target delivery and application.

Enteric Release Essential Oil Prepared by Co-Spray Drying Methacrylate/Polysaccharides-Influence of Starch Type

Oregano essential oil (EO) enteric release powder was formulated by spray drying feed emulsions stabilized with polysaccharides (PSC) and Eudragit® L100 (PLM). Different modified starches were used in the PSC component. Spray-dried powders were evaluated for particle size and morphology, dynamic packing, flowability, chemical interactions, reconstitution, and gastric protection. Feed emulsions were stable, indicating the good emulsification ability of the PLM/PSC combination. The presence of polymer in the encapsulating wall neutralized electrostatic charges indicating physical attraction, and FTIR spectra showed peaks of both PLM and PSC without significant shifting. Furthermore, the presence of polymer influenced spray drying, resulting in the elimination of surface cavities and the improvement of powder packing and flowability, which was best when the surface-active, low-viscosity sodium octenyl succinate starch was used (angle of repose 42°). When a PLM/PSC ratio of 80/20 was used in the encapsulating wall, the spray-dried product showed negligible re-emulsification and less than 15% release in pH 1.2 medium for 2 h, confirming gastric protection, whereas at pH 6.8, it provided complete re-emulsification and release. In conclusion, (1) polymer-PSC physical interaction promoted the formation of a smoother particle surface and product with improved technological properties, which is important for further processing, and (2) the gastro protective function of Eudragit® L100 was not impaired due to the absence of significant chemical interactions.

Stability and in vitro simulated release characteristics of ultrasonically modified soybean lipophilic protein emulsion

Natural emulsifiers such as soybean lipophilic protein (SLP) show potential as delivery systems for hydrophobic bioactive components such as vitamin E; however, the solubility of SLP is limited by its high lipid content. This study evaluated the effects of various ultrasonic conditions on the structure and properties of SLP. Using an emulsion of modified SLP, the carrier properties and in vitro digestion and release properties for vitamin E were evaluated. Biochemical and spectroscopic analyses indicated that the ultrasonic treatment mainly changed the secondary and tertiary structures of SLP. Furthermore, appropriate ultrasonic conditions significantly improved the solubility and emulsifying properties of SLP, with the highest emulsion stability and SLP encapsulation efficiency obtained using an ultrasonic power of 240 W for 20 min. An in vitro digestion simulation revealed that the emulsion prepared by ultrasonic modification of SLP was an effective delivery system for vitamin E. In particular, the emulsion protected the biological activity of vitamin E while significantly increasing the rate of lipid digestion and the bioavailability of vitamin E. These results indicate that the ultrasonically modified SLP can be used to prepare a stable emulsion for encapsulating vitamin E, which provides a new approach for the delivery of hydrophobic bioactive components.

Citrullus lanatus essential oils inclusion in diets elicit nutraceutical effects on egg production, egg quality, and physiological characteristics in layer hens

The study evaluated the effects of Citrullus lanatus essential oils inclusion in diet on egg production, egg quality, and physiological parameters in layer hens. A total of 72 White Leghorn point-of-lay hens at 18 wk were used for the study. The hens were randomly allocated to following 3 dietary treatments: 1) commercial layer diet (control), 2) commercial diet + 1 g C. lanatus essential oil/kg feed (1gCL), and 3) commercial diet + 2 g C. lanatus essential oil/kg feed (2gCL). Each treatment was replicated 8 times arranged in completely randomized design. From the results, an increase in total weight gain, average daily feed intake, and average daily gain was observed with inclusion of the C. lanatus essential oil. In addition, the inclusion of C. lanatus in diet improved the egg mass and feed conversion ratio (FCR). Hens fed C. lanatus-containing diets had higher egg mass (1gCL, 53.35 g ± 0.71; 2gCL, 53.99 ± 0.71 g) compared with the control (52.90 ± 0.71). The C. lanatus containing diets also had lower FCR than the control (1gCL [2.18 ± 0.22] and 2gCL [2.16 ± 0.22] vs. control [2.20 ± 0.71]). With regards to egg quality parameters, inclusion of C. lanatus oil appeared to reduce shell weight and shell ratio, while increasing albumen height and Haugh unit. Diets containing C. lanatus had significantly higher amounts of stearic acid, and linoleic acid was highest (P < 0.05) in the 2gCL fed hens. Birds fed the 2gCL diet (15.29 ± 0.60) had the highest total polyunsaturated fatty acids, total n-6 fatty acids (14.81 ± 0.59) and also had the highest n-6/n-3 ratio. An increase hematological values was observed with inclusion of C. lanatus essential oils in diets. Moreover, tibia bone parameters were also significantly improved with inclusion of C. lanatus essential oils in diets. It can be concluded that C. lanatus essential oil positively affected egg production, and quality and health of layer hens can be used successfully as a natural feed additive.

Effect of Housing System and Rosemary and Cinnamon Essential Oils on Layers Performance, Egg Quality, Haematological Traits, Blood Chemistry, Immunity, and Antioxidant

Simple Summary

The current study aimed to investigate the effects of a housing system, and dietary supplementation of rosemary and cinnamon essential oils on layers performance and egg quality. A factorial arrangement (2 × 3) was performed including two housing systems (floor and cage) and three different types of essential oils (0, 300 mg/kg diet of rosemary and 300 mg/kg diet of cinnamon essential oils) to study their effects on the productive performance, egg quality, immunity, oxidative stress and haematology of laying hens during the production stages. The data suggested that the supplementation of rosemary and cinnamon essential oils in laying hen diet showed significant positive effects on hen performance and egg production. Additionally, the different housing systems did not result in any positive or negative impact on these traits.

Abstract

Housing system and nutrition are non-genetic factors that can improve the well-being of animals to obtain higher quality products. A better understanding of how different housing systems and essential oils can influence the performance of layers is very important at the research and commercial levels. The current study aimed to investigate the effects of a housing system and dietary supplementation of rosemary and cinnamon essential oils on layers’ performance and egg quality. A factorial arrangement (2 × 3) was performed include two housing systems (floor and cage) and three different types of essential oils (0, 300 mg/kg diet of rosemary and 300 mg/kg diet of cinnamon essential oils) to study their effects on the productive performance, egg quality, immunity, oxidative stress and haematology of ISA brown laying hens during the production stages (from 28 to 76 weeks of age). Birds were randomly divided into two groups each comprising of 1500 birds; the first group was moved from the litter to reared laying cages while the second group was floor reared. Each group was randomly divided into three groups, the first was considered as a control group, the second treated with rosemary essential oil, and the third with cinnamon essential oil. The differences in egg production and weight, egg quality, feed intake and conversion, blood picture and chemistry, immunity, and antioxidant parameters between the different housing systems (floor and cage) were not significant at (p < 0.05 or 0.01). On the other hand, the egg production and weight, Haugh unit, feed intake and conversion, blood cholesterol, Alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST), urea, Ca, P, immunity, and antioxidant parameters were significantly (p < 0.05 or 0.01) better in rosemary and cinnamon groups than in the control group. Furthermore, the results of dietary supplementation with rosemary and cinnamon were very close. Regarding egg production and weight, there were no significant differences due to the interactions. The differences in egg mass among the interactions were also not significant except at 68–76 weeks, where the cage × cinnamon group was the highest. Under the floor rearing system, birds that were fed a diet supplemented with or without essential oils (EOs) consumed more feed than those raised under the cage system. Regarding feed conversion rate (FCR), the differences among the interactions were not significant except at 44–52, 52–60 and 68–76 weeks, where the cage × cinnamon group was the lowest. Excluding glutathione peroxidase (GPx) activity (p < 0.001), all immunity and antioxidant indices were not statistically different as a consequence of the interaction among EOs and housing systems. Additionally, the highest levels of phosphorus were observed for layers fed diets enriched with cinnamon oil with the cage or floor system. In conclusion, the data suggested that supplementation of rosemary and cinnamon essential oils in laying hen diet showed significantly positive effects on hen performance and egg production. Cholesterol, liver and kidney functions, immunity, and antioxidant parameters improved with rosemary and cinnamon supplementation when compared to the control. Additionally, the different housing systems did not result in any positive or negative impact on these traits.

Effects of encapsulated cinnamaldehyde and citral on the performance and cecal microbiota of broilers vaccinated or not vaccinated against coccidiosis

This study investigated the effects of encapsulated cinnamaldehyde (CIN) and citral (CIT) alone or in combination (CIN + CIT) on the growth performance and cecal microbiota of nonvaccinated broilers and broilers vaccinated against coccidiosis. Vaccinated (1,600) and nonvaccinated (1,600) 0-day-old male Cobb500 broilers were randomly allocated to 5 treatments: basal diet (control) and basal diet supplemented with bacitracin (BAC, 55 ppm), CIN (100 ppm), CIT (100 ppm), and CIN (100 ppm) + CIT (100 ppm). In general, body weight (BW) and feed conversion ratio were significantly improved in birds treated with BAC, CIN, CIT, and CIN + CIT (P < 0.05) but were all decreased in vaccinated birds compared with nonvaccinated birds (P < 0.05). Significant interactions (P < 0.05) between vaccination and treatments for average daily gain during the periods of starter (day 0–9) and BW on day 10 were noted. Broilers receiving vaccines (P < 0.01) or feed supplemented with BAC, CIN, CIT, or CIN + CIT (P < 0.01) showed reductions in mortality rate from day 0 to 28. The incidences of minor coccidiosis were higher (P < 0.05) in vaccinated birds than in nonvaccinated birds. Diet supplementation with BAC or tested encapsulated essential oils showed comparable effects on the coccidiosis incidences. Similar to BAC, CIN and its combination with CIT reduced both incidence and severity of necrotic enteritis (P < 0.05). No treatment effects were observed on the cecal microbiota at the phyla level. At the genus level, significant differences between vaccination and treatment groups were observed for 5 (Lactobacillus, Ruminococcus, Faecalibacterium, Enterococcus, and Clostridium) of 40 detected genera (P < 0.05). The genus Lactobacillus was more abundant in broilers fed with CIT, while Clostridium and Enterococcus were less abundant in broilers fed with CIN, CIT, or CIN + CIT in both the vaccinated and nonvaccinated groups. Results from this study suggested that CIN alone or in combination with CIT in feed could improve chicken growth performance to the level comparable with BAC and alter cecal microbiota composition.

Evaluation of lipid matrix microencapsulation for intestinal delivery of thymol in weaned pigs

Essential oils (EO) are defined as plant-derived natural bioactive compounds, which can have positive effects on animal growth and health due to their antimicrobial and antioxidative properties. However, EO are volatile, can evaporate quickly, and be rapidly absorbed in the upper gastrointestinal tract. Also, due to their labile nature, the stability of EO during feed processing is often questionable, leading to variations in the final concentration in feed. Encapsulation has become one of the most popular methods of stabilizing EO during feed processing, storage, and delivery into the lower gut. The objectives of the present study were to 1) evaluate the stability of thymol microencapsulated in combination with organic acids in commercially available lipid matrix microparticles during the feed pelleting process and storage; 2) validate and demonstrate the slow release of thymol from the lipid matrix microparticles in a simulated pig gastric fluid (SGF) and a simulated pig intestinal fluid (SIF); and 3) evaluate in vivo release of thymol from the lipid matrix microparticles along the pig gut. The results showed that thymol concentration was not significantly different in the mash and pelleted feeds (P > 0.05). In the in vitro study, 26.04% thymol was released in SGF, and the rest of the thymol was progressively released in SIF until completion, which was achieved by 24 h. The in vivo study showed that 15.5% of thymol was released in the stomach, and 41.85% of thymol was delivered in the mid-jejunum section. Only 2.21% of thymol was recovered in feces. In conclusion, the lipid matrix microparticles were able to maintain the stability of thymol during a feed pelleting process and storage and allow a slow and progressive intestinal release of thymol in weaned pigs.

Using zeta potential to study the ionisation behaviour of polymers employed in modified-release dosage forms and estimating their pKa

A range of enteric polymers is used in pharmaceutical industry for developing gastro-resistant formulations. It is generally implied that these coatings are interchangeable due to similar dissolution pH thresholds reported by suppliers. Despite rapid dissolution in compendial phosphate buffers, these products can take up to 2 h to disintegrate in-vivo in the human small intestine. The factors primarily responsible for such variability in dissolution of these polymeric coatings are the differences in ionisation of acidic functional groups on polymer chains and their interplay with ions and buffer species present in gastrointestinal fluids. In this study, we aim to develop a novel, simple and inexpensive technique that can be used under various in-vitro conditions to study the ionisation behaviour of commonly used polymers (EUDRAGIT-E100, L100, S100, HPMC AS-LF, AS-HF, HP-50, HP-55) and to estimate their pK_a. Moreover, this method was successfully applied to study the ionisation behaviour of a range of natural polymers (Guar, Tara, locust bean, Konjac gums, gum Arabic, citrus pectin, chitosan and alginate) and their pK_a was also estimated. The proposed method would allow a better understanding of the dissolution behaviour of these polymers within gastrointestinal tract and will aid rational design of modified release dosage forms.

Comparative effects of powder, aqueous and methanolic extracts of purslane (Portulaca oleracea L.) on growth performance, antioxidant status, abdominal fat deposition and plasma lipids in broiler chickens

This study was performed to evaluate the comparative effects of dietary supplementation of dried purslane powder (PP), purslane aqueous extract (PAE) and purslane methanolic extract (PME) on performance, antioxidant status, carcass traits and selected plasma lipid parameters in broiler chickens. In total, 420 1-day-old male broiler chicks were divided into seven treatments for 49 days as follows: control (basal diet), basal diets plus 1500 or 3000 mg/kg of PP (PP1500 and PP3000 respectively), basal diets plus 150 or 300 mg/kg of PAE (PAE150 and PAE300 respectively) and basal diets plus 150 or 300 mg/kg of PME (PME150 and PME300 respectively). During the total period of the experiment (0–49 days of the experiment), birds receiving the PP3000 diet had higher (P &lt; 0.05) bodyweight gain and a lower feed conversion ratio compared with those fed other diets. At 24 and 49 days of the experiment, birds receiving the PP3000 diet showed greater (P &lt; 0.05) plasma and liver activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx), and lower (P &lt; 0.05) plasma and liver levels of malondialdehyde compared with other dietary treatments. Additionally, at 24 days of the experiment, birds receiving the PP3000 diet had a greater (P &lt; 0.05) liver catalase activity than those receiving other dietary treatments. In addition, groups receiving the PP1500, PAE300 or PME300 diets showed greater (P &lt; 0.05) plasma and liver activities of superoxide dismutase, catalase and glutathione peroxidase, as well as lower (P &lt; 0.05) plasma and liver levels of malondialdehyde compared with the control group. At 24 days of the experiment, birds receiving the PP1500 or PP3000 diets showed greater (P &lt; 0.05) jejunal activities of superoxide dismutase, catalase and glutathione peroxidase than other groups. At 49 days of the experiment, birds receiving the PP3000 diet showed greater (P &lt; 0.05) jejunal activities of superoxide dismutase and glutathione peroxidase compared with the control group. Additionally, at both 24 and 49 days of the experiment, groups receiving the PP3000 diet had lower (P &lt; 0.05) jejunal levels of malondialdehyde compared with the control group. At 49 days of the experiment, birds receiving the PP3000 diet had a lower (P &lt; 0.05) relative weight of abdominal fat compared with those receiving the other dietary treatments. Moreover, groups that consumed the PP1500, PAE300 or PME300 diets showed lower (P &lt; 0.05) relative weights of abdominal fat compared with the control group. Groups fed PP, PAE or PME treatments showed lower (P &lt; 0.05) plasma levels of triglycerides, total cholesterol and low-density lipoprotein cholesterol, and higher (P &lt; 0.05) plasma levels of high-density lipoprotein cholesterol than the control group at 24 and 49 days of the experiment, with the most pronounced effects observed in those receiving the PP3000 treatment. In conclusion, PP showed more beneficial effects than PAE and PME, and 3000 mg/kg was the best inclusion level of PP in broiler chicken diets.

Ultrasound-assisted preparation of flaxseed oil nanoemulsions coated with alginate-whey protein for targeted delivery of omega-3 fatty acids into the lower sections of gastrointestinal tract to enrich broiler meat

Flaxseed oil is one of the richest sources of α-linolenic acid (ALA). However, the susceptibility of ALA to oxidation and also lack of the convenient methods to deliver these invaluable compound into the lower sections of gastrointestinal tract (GIT) are still unknown. The objective of the current study was to establish a method for ALA targeted delivery into the lower sections of GIT to enrich broiler meat. An in vitro study was performed to use ultrasound to produce oil-in-water nanoemulsions of flaxseed oil stabilized by different wall materials for controlled release of ALA in GIT. The fabricated nanoemulsions were assessed in terms of particle size distribution, zeta-potential, encapsulation efficiency, field emission scanning electron microscopy (FESEM), and in vitro gastric and intestinal digestions. Results indicated that the nanoemulsions coated by a combination of whey protein-sodium alginate (WP/SA) had a relatively uniform distribution and all particles distributed in less than 1000 nm. The values of zeta-potential for nanoemulsions stabilized by whey protein (WP), sodium alginate (SA) and WP/SA were -31.4, -29.3 and -45.5 mV, respectively. The wall combination of WP/SA showed the best encapsulation efficiency followed by WP. The FESEM results indicated spherical and non-aggregated structures for three types of nanoemulsions. The nanoemulsions stabilized by WP/SA showed a high resistance to in vitro gastric digestion but a relatively rapid release during intestinal digestion. An in vivo study was conducted to enrich broiler meat with ALA, using the best wall material from the in vitro study. In total, 300 one-day-old broilers (Ross, 308) were assigned into 5 experimental treatments including: basal diet (BD), basal diet plus flaxseed oil (BD + FO, 1 mL/kg body weight), basal diet plus ultrasonicated flaxseed oil nanoemulsions stabilized by WP/SA (BD + FON, 1 mL/kg body weight), basal diet plus flaxseed oil and vitamin E (BD + FO + E, 1 mL/kg body weight and 200 mg/kg diet vitamin E) and basal diet plus ultrasonicated flaxseed oil nanoemulsions stabilized by WP/SA and vitamin E (BD + FON + E, 1 mL/kg body weight of nanoemulsion and 200 mg/kg diet vitamin E). Each experimental treatment included 4 replicates in a completely randomized design. Results showed a better feed conversion ratio (FCR) in birds treated with dietary treatments compared with those received basal diet. A greater incorporation of ALA and total poly unsaturated fatty acids (PUFA) omega-3 were observed in thigh and breast meat of birds fed by ultrasonicated flaxseed oil nanoemulsions. In comparison to birds fed with BD, a favourably lower PUFA omega-6/omega-3 ratio was observed in birds received nanoemulsions of flaxseed oil. In general, the current study showed that using ultrasound to produce nanoemulsions stabilized by WP/SA has potential to protect ALA of flaxseed oil from gastric digestion and could be used as delivery carriers of ALA omega-3 fatty acid to the posterior sections of chicken GIT. Moreover, ultrasonic fabrication of nanoemulsion has potential to enrich broiler meat by ALA fatty acid.

Essential Oils as Feed Additives-Future Perspectives

The inconsistency of phytogenic feed additives' (PFA) effects on the livestock industry poses a risk for their use as a replacement for antibiotic growth promoters. The livestock market is being encouraged to use natural growth promotors, but information is limited about the PFA mode of action. The aim of this paper is to present the complexity of compounds present in essential oils (EOs) and factors that influence biological effects of PFA. In this paper, we highlight various controls and optimization parameters that influence the processes for the standardization of these products. The chemical composition of EOs depends on plant genetics, growth conditions, development stage at harvest, and processes of extracting active compounds. Their biological effects are further influenced by the interaction of phytochemicals and their bioavailability in the gastrointestinal tract of animals. PFA effects on animal health and production are also complex due to various EO antibiotic, antioxidant, anti-quorum sensing, anti-inflammatory, and digestive fluids stimulating activities. Research must focus on reliable methods to identify and control the quality and effects of EOs. In this study, we focused on available microencapsulation techniques of EOs to increase the bioavailability of active compounds, as well as their application in the animal feed additive industry.

Potential of essential oils for poultry and pigs

The increasing pressure of abolishing and/or decreasing the use of antibiotics as antimicrobial growth promoters for livestock calls for alternative solutions to sustain the efficiency of current livestock production. Among the alternatives, essential oils have a great potential and are generally considered natural, less toxic, and free from residues. Essential oils have been proven in numerous in vitro studies to exert antimicrobial effects on various pathogens. The current review touched on the basics of essential oils, and the in vivo effects of essential oils on growth, intestinal microflora, anti-oxidation, immune functionality, meat qualities as well as the possible modes of action in poultry and pigs, and the future research areas were proposed.

Evaluation of alginate-whey protein microcapsules for intestinal delivery of lipophilic compounds in pigs

BACKGROUND

In animal care and management, there is an increasing demand for convenient methods of oral delivery of bioactive compounds to specific segments of an animal's gastrointestinal tract. The objective of this study was to test the suitability of microcapsules made with alginate and whey proteins of two different sizes (250 and 800 µm; containing 72 and 76 g kg(-1) of carvacrol respectively) for intestinal delivery of carvacrol in pigs.

RESULTS

Encapsulated carvacrol was completely released from the microcapsules after 5 h incubation in simulated intestinal fluids or 6 h in (ex vivo) ileal digesta, whereas release in simulated gastric fluid was minimal. Tests with growing pigs showed over 95% of unencapsulated carvacrol was absorbed or metabolized in the stomach and the duodenum. Encapsulation effectively minimized carvacrol absorption in the stomach (P < 0.05), and increased carvacrol recovery in the small intestine (P < 0.05). Encapsulated carvacrol was completely released from both small and large size capsules within the gastrointestinal tract of pigs. Larger size microcapsules showed a slower in vitro release and greater in vivo recovery of carvacrol in the small intestine (P < 0.05) than the smaller ones.

CONCLUSION

This study indicates alginate-whey protein microencapsulation is a feasible approach for targeted oral delivery of hydrophobic compounds to pig intestines; increasing capsule size increased delivery of carvacrol to the end of the small intestine. © 2015 Her Majesty the Queen in Right of Canada Journal of the Science of Food and Agriculture © 2015 Society of Chemical Industry.

Phytogenic compounds as alternatives to in-feed antibiotics: potentials and challenges in application

This article summarizes current experimental knowledge on the efficacy, possible mechanisms and feasibility in the application of phytogenic products as feed additives for food-producing animals. Phytogenic compounds comprise a wide range of plant-derived natural bioactive compounds and essential oils are a major group. Numerous studies have demonstrated that phytogenic compounds have a variety of functions, including antimicrobial/antiviral, antioxidative and anti-inflammation effects and improvement in the palatability of feed and gut development/health. However, the mechanisms underlying their functions are still largely unclear. In the past, there has been a lack of consistency in the results from both laboratory and field studies, largely due to the varied composition of products, dosages, purities and growing conditions of animals used. The minimal inhibitory concentration (MIC) of phytogenic compounds required for controlling enteric pathogens may not guarantee the best feed intake, balanced immunity of animals and cost-effectiveness in animal production. The lipophilic nature of photogenic compounds also presents a challenge in effective delivery to the animal gut and this can partially be resolved by microencapsulation and combination with other compounds (synergistic effect). Interestingly, the effects of photogenic compounds on anti-inflammation, gut chemosensing and possible disruption of bacterial quorum sensing could explain a certain number of studies with different animal species for the better production performance of animals that have received phytogenic feed additives. It is obvious that phytogenic compounds have good potential as an alternative to antibiotics in feed for food animal production and the combination of different phytogenic compounds appears to be an approach to improve the efficacy and safety of phytogenic compounds in the application. It is our expectation that the recent development of high-throughput and "omics" technologies can significantly advance the studies on the mechanisms underlying phytogenic compounds' functions and, therefore, guide the effective use of the compounds.