Nutritional characteristics and quality of eggs from laying hens fed on a diet supplemented with chestnut tannin extract (Castanea sativa Miller)

Beneficial Effects of Castanea sativa Wood Extract on the Human Body and Possible Food and Pharmaceutical Applications

The aim of this review was to investigate the potential use of Castanea sativa wood extract as a food supplement and to evaluate its beneficial properties for human health. The results of the limited amount of studies suggest promising properties, including potential anti-inflammatory effects. The literature indicates that the extract, which is rich in bioactive compounds such as tannins, offers promising therapeutic possibilities for the treatment of conditions associated with chronic inflammation. Consequently, interest in its use in food and pharmaceuticals is growing. Phytochemical studies have reported antioxidant and antimicrobial activities, and anti-inflammatory, anticancer, hypolipidemic, hypoglycemic, and neuroprotective activities. A suitable extraction method and solvent is crucial for the isolation of bioactive compounds, being green extraction technologies outstanding for the industrial recovery of chestnut wood's bioactive compounds. Nevertheless, it is important to emphasize the importance of adhering to regulatory guidelines and obtaining the necessary approvals from regulatory authorities to ensure product safety and compliance. The regulation of herbal medicinal products with proven efficacy and traditional herbal medicinal products is well defined, monitored by authorized bodies, and subject to strict control measures. It is noteworthy that medicinal products are subject to stringent quality testing to ensure safety and efficacy in use, whereas there are no comparable regulatory standards and specific labeling requirements for dietary supplements. When using herbal products, compliance with established standards in health research is essential.

Tannins-Based Extracts: Effects on Gut Chicken Spontaneous Contractility

The impossibility of using drugs for the health of farm animals leads to the search for alternative strategies with two purposes: to maintain animal health and safeguard human health. In this perspective, tannins have shown great promises. These phytocomplexes obtained from natural matrices with multiple health properties may be used as a feed supplement in chicken farms. In this work, we studied two tannin-based extracts (from Castanea sativa Mill. wood and from Schinopsis balansae Engl. Quebracho Colorado hardwood) with different chemical compositions on the spontaneous contractility on the isolated intestinal tissues of healthy chicken. The results showed that the chemical composition of the two phytocomplexes influenced the spontaneous intestinal contractility in different ways by regulating the tone and consequent progression of the food bolus. The chemical analysis of the two extracts revealed that Castanea sativa Mill. wood mainly contains hydrolysable tannins, while Schinopsis balansae Engl. hardwood mainly contains condensed tannins. The two phytocomplexes showed different effects towards gastrointestinal smooth muscle contractility, with Castanea sativa Mill. wood providing a better activity profile than Schinopsis balansae Engl. hardwood.

Effect of Hydrolyzed Gallotannin on Growth Performance, Immune Function, and Antioxidant Capacity of Yellow-Feather Broilers

Tannins were traditionally considered as anti-nutritional factors in poultry production. Recent studies found that the addition of hydrolyzed gallotannin (HGT) could improve animal health; however, the proper dosage of HGT in chickens' diet is still unknown. Hence, our study aims to recommend its optimal dose by exploring the effects of HGT from Chinese gallnuts on the growth performance, immune function, and antioxidant capacity of yellow-feather broilers. A total of 288 male yellow-feather broilers (34.10 ± 0.08 g) were randomly allocated to four diet treatments, the basal diet with 0 (CON), 150, 300, and 450 mg/kg HGT for 63 days, respectively, with six replications per treatment and 12 birds per replication. The growth performance, slaughter performance, immune organ index, liver antioxidant-related indicators, and serum immune-related factors were evaluated. Results show that HGT supplementation did not influence the growth performance of broilers, but the diets supplemented with 300 and 450 mg/kg HGT increased the semi-eviscerated rate. Furthermore, HGT increased the content of liver T-AOC and the ratio of GSH/GSSG, which can protect against oxidative damage of birds. Additionally, supplementing HGT raised the contents of serum IL-10, IL-4, IL-6, IgA, and IgM. In conclusion, diet supplemented with 450 mg/kg HGT may be the optimal to the health of yellow-feather broilers on the whole.

Polyphenolic phytochemicals as natural feed additives to control bacterial pathogens in the chicken gut

Poultry provides an important protein source consumed globally by human population, and simultaneously, acts as a substantial reservoir of antibiotic resistant bacterial species such as Escherichia coli, Salmonella, Campylobacter, Clostridium perfringens. These bacterial species can include commensal strains with beneficial roles on poultry health and productivity, and pathogenic strains not only to poultry but zoonotically to man. This review paper evaluates the role of phytochemicals as possible alternatives to antibiotics and natural anti-bacterial agents to control antibiotic resistance in poultry. The focus of this paper is on the polyphenolic phytochemicals as they constitute the major group; carvacrol oil (the active ingredient of oregano), thymol oil (the main ingredient of oregano), oregano oil, and tannins oil as feed additives and their mechanism of actions that might enhance avian gut health by controlling antibiotic-resistant bacterial strains spread in poultry.

Castanea sativa shells: A review on phytochemical composition, bioactivity and waste management approaches for industrial valorization

Castanea sativa is an outstanding species that represents a valuable natural resource for rural populations. C. sativa shells (CSS), an abundant agro-industrial by-product generated during chestnut peeling process, is commonly discarded or used as fuel. Nevertheless, CSS produced are not depleted by this application and huge amounts are still available, being particularly rich in bioactive compounds (polyphenols, vitamin E, lignin and oligosaccharides) with health benefits. Phytochemical studies reported not only antioxidant and antimicrobial activities, but also anti-inflammatory, anticancer, hypolipidemic, hypoglycemic and neuroprotective activities. The application of a suitable extraction technique is required for the isolation of bioactive compounds, being green extraction technologies outstanding for the industrial recovery of chestnut shells' bioactive compounds. CSS were highlighted as remarkable sources of functional ingredients with promising applications in food and nutraceutical fields, mainly as natural antioxidants and effective prebiotics. This review aims to summarize the phytochemical composition and pro-healthy properties of CSS, emphasizing the sustainable extraction techniques employed in the recovery of bioactive compounds and their potential applications in food and nutraceutical industries.

Overview of Native Chicken Breeds in Italy: Conservation Status and Rearing Systems in Use

Simple Summary

The ongoing loss of domestic animal breeds around the world is occurring at an alarming rate. Thus, the registration and preservation of native breeds is of great importance. The aim of this study, which forms part of a conservation program, was to provide an overview of the conservation statuses of native Italian poultry breeds being reared by local breeders in Italy. The data collected by means of a census questionnaire demonstrate the low population sizes of these breeds in Italy and highlight the need for campaigns aimed at publicizing and promoting the benefits of native breeds with the goal of increasing population sizes. Identifying strategies to facilitate breeders’ access to pure breed birds is also essential, and would require collaborative efforts of university research centers, public entities, and breeders.

Abstract

The most reared species of farm animal around the world is the chicken. However, the intensification of livestock systems has led to a gradual increase in the concentration of a limited number of breeds, resulting in substantial erosion to the genetic pool. The initial step of an ‘animal conservation program’ entails establishing the actual conservation statuses of the breeds concerned in a defined area; in this case, in Italy. To this end, a survey of breeds was performed by means of a census questionnaire divided into two parts. The first part collected information on breeds, breeders, housing facilities, and management aspects, the results of which are presented here. The second part of the questionnaire regarded chicken products and their markets, and these data will be reported in a second paper. The breed status of six chicken breeds was shown to be exceptionally worrying, with total numbers ranging from just 18 to 186 birds. Population sizes exceeding 1000 birds was identified for just four breeds, the maximum being 3400. Some improvements in status were noted in relation to breeds which had been the subject of conservation efforts in the past. The two most common breeds reported are the Bionda Piemontese, a double-purpose breed, and the Livorno egg-laying hen. Collo Nudo Italiano, Millefiori Piemontese, Pollo Trentino, and Tirolese chicken breeds and the Castano Precoce turkey breed were not listed by breeders at all. The most reported turkey breeds are the Bronzato Comune and the Ermellinato di Rovigo. The population sizes of native Italian poultry breeds were shown to be generally poor. Italian poultry farmers and the population at large are largely ignorant about indigenous poultry breeds. Thus, promoting the virtues of Italian breeds would help their conservation by encouraging breeders to rear these birds and consumers to buy their products. The identification of strategies to facilitate access to pure breed birds is essential, and will require the collaboration of university research centers, public entities, and breeders. The results presented in this paper constitute the initial part of a more complex conservation program.

The Effects of Tannins in Monogastric Animals with Special Reference to Alternative Feed Ingredients

Over recent years, the monogastric animal industry has witnessed an increase in feed prices due to several factors, and this trend is likely to continue. The hike in feed prices is mostly due to extreme competition over commonly used conventional ingredients. For this trend to be subdued, alternative ingredients of both plant and animal origin need to be sourced. These types of ingredients are investigated with the aim of substituting all or some of the conventional compounds. However, alternative ingredients often have a double-edged sword effect, in that they can supply animals with the necessary nutrients although they contain antinutritional factors such as tannins. Tannins are complex secondary metabolites commonly present in the plant kingdom, known to bind with protein and make it unavailable; however, recently they have been proven to have the potential to replace conventional ingredients, in addition to their health benefits, particularly the control of zoonotic pathogens such as Salmonella. Thus, the purpose of this review is to (1) classify the types of tannins present in alternative feed ingredients, and (2) outline the effects and benefits of tannins in monogastric animals. Several processing methods have been reported to reduce tannins in diets for monogastric animals; furthermore, these need to be cost-effective. It can thus be concluded that the level of inclusion of tannins in diets will depend on the type of ingredient and the animal species.

Performance of Slow-Growing Male Muscovy Ducks Exposed to Different Dietary Levels of Quebracho Tannin

Simple Summary

Different inclusion levels of Quebracho tannin (QT) in the diet of growing male Muscovy ducks of a slow-growing type were explored under free-range conditions. As a result of the dietary treatments tested in this trial, the growth performance or the total blood proteins were not affected. By contrast, dietary QT did not lead birds to produce less moist excreta, as observed in other bird species, as a desirable aspect for intensively raised poultry. A marked improvement in carcass yield was observed as a desirable economic trait in the extensive slow-type duck farming system.

Abstract

The study of the nutritional effects of tannins is complex due to the large chemical diversity; consequently, in poultry nutrition the biological responses may vary greatly. The aim of the present study was to evaluate the effect of different levels of dietary Quebracho tannins (QT) on growth and production performance in slow-growing type Muscovy ducks. For this purpose, a 42-d trial was carried out on 126 male ducks (42-d old at start), fed on three levels of dietary QT inclusion in the diet (0% as control diet, vs. 1.5% vs. 2.5% on an as fed basis). Birds were reared under free-range conditions. A linear increase in feed intake as a function of QT inclusion in the diet was observed (p < 0.05). No difference as to final body weight, overall average daily weight gain (ADG) and total feed conversion ratio (FCR) in relation to dietary treatments was observed. Carcass yields were positively improved in QT birds (p < 0.05). No adverse responses were recorded in total blood protein and liver weight. Dietary QT might be safely used up by to 2.5% in 42- to 84-d aged male Muscovy ducks.

Effect of Breed and Diet Type on the Freshness and Quality of the Eggs: A Comparison between Mos (Indigenous Galician Breed) and Isa Brown Hens

Eggs are a nutritious food, offering a balanced source of essential amino and fatty acids, minerals, and vitamins. Genetic and diet factors can modify hen egg traits. Thus, the effects of breed and feed on egg quality using two laying hens, Mos (autochthonous breed) and Isa Brown (commercial hybrid), and three feeds, commercial fodder (CF), corn/pea/triticale (CPT) and corn/wheat (CW), were investigated. Freshness parameters (egg weight, eggshell weight and thickness, albumen height, Haugh units and yolk color), chemical composition, color and textural parameters, as well as fatty acid profile, were assessed on a total of 288 eggs, from the two breeds. The samples were divided in 96 eggs, corresponding to each of the three dietary treatments. There were significant differences (p < 0.001) in albumen height and Haugh units, obtaining the highest values for Isa Brown genotype; meanwhile, laying hens fed with CF had the highest weight, as well as the greatest eggshell thickness. Cooked yolks of Isa Brown eggs presented the highest values of luminosity, while the yellowness was higher for Mos eggs. Regarding the texture of eggs, genotype was again the parameter having the greatest impact, obtaining higher values in hardness, gumminess and chewiness in those eggs from the Mos breed. Concerning egg chemical composition, it was affected by breed and diet type, but Mos eggs were characterized by a significantly (p < 0.001) higher contents of fat (9.53% vs. 7.58%), protein (12.31% vs. 11.66%) and ash (1.10% vs. 1.04%) than Isa Brown ones. Finally, diet type influenced the fatty acid profile, mainly affecting oleic and linoleic acids, which showed significantly (p < 0.05) highest values (42.90 and 14.66 g/100 g of total fatty acids) in CW and CF diets, respectively. Overall, breed and bird diet factors had a strong effect on egg quality and nutritional profile. Moreover, eggs from Mos hens had more attractive nutritional indices, and they could even be improved more by changing the diet.

Dietary supplementation of chestnut and quebracho tannins mix: Effect on caecal microbial communities and live performance of growing rabbits

The interest in antimicrobial compounds as feed additives is currently increasing. Among different options, tannins seem to have several beneficial effects when employed in animals diet. The present study aimed at investigating the influence on caecal microbial communities of the supplementation of a chestnut and quebracho tannins mix in meat rabbit's diet, also considering animals live performances. Four groups of rabbits were fed with a different diet: a control diet (C); a control diet with coccidiostat (CC), and two experimental diets with 0.3% (T0.3) and 0.6% (T0.6) chestnut and quebracho tannins mix. For microbial analysis, culture-dependent and culture-independent methods were employed. Live performances were not significantly affected by tannins mix supplementations, as well as culturable microbial loads of E. coli, Enterobacteriaceae, Bacteroides spp. and Bifidobacterium spp. C. perfringens was always under the detection limit. A consistent result was obtained by qPCR. As for PCR-DGGE analysis, the Richness and evenness (Shannon-Weiner index) of bacterial communities in caecum resulted significantly higher in control samples (C and CC) than in those from rabbit fed with tannin-containing diets. Sequencing analysis revealed that the phylum Firmicutes was less represented in samples from control groups. As for the methanogen archaeal DGGE, no significant differences were found in richness and diversity among different groups, all dominated by Methanobrevibacter spp.. This work highlights the potential antimicrobial effect of chestnut and quebracho tannins mix in an in vivo system revealed by molecular analysis.

Natural Phenol Polymers: Recent Advances in Food and Health Applications

Natural phenol polymers are widely represented in nature and include a variety of classes including tannins and lignins as the most prominent. Largely consumed foods are rich sources of phenol polymers, notably black foods traditionally used in East Asia, but other non-edible, easily accessible sources, e.g., seaweeds and wood, have been considered with increasing interest together with waste materials from agro-based industries, primarily grape pomace and other byproducts of fruit and coffee processing. Not in all cases were the main structural components of these materials identified because of their highly heterogeneous nature. The great beneficial effects of natural phenol-based polymers on human health and their potential in improving the quality of food were largely explored, and this review critically addresses the most interesting and innovative reports in the field of nutrition and biomedicine that have appeared in the last five years. Several in vivo human and animal trials supported the proposed use of these materials as food supplements and for amelioration of the health and production of livestock. Biocompatible and stable functional polymers prepared by peroxidase-catalyzed polymerization of natural phenols, as well as natural phenol polymers were exploited as conventional and green plastic additives in smart packaging and food-spoilage prevention applications. The potential of natural phenol polymers in regenerative biomedicine as additives of biomaterials to promote growth and differentiation of osteoblasts is also discussed.