Effect of Green Tea By-product on Performance and Body Composition in Broiler Chicks

Effect of tea polyphenols on intestinal barrier and immune function in weaned lambs

Introduction

The purpose of this study was to explore the effects of tea polyphenols on growth performance, cytokine content, intestinal antioxidant status and intestinal barrier function of lambs, in order to provide reference for intestinal health of ruminants.

Methods

Thirty weaned lambs (average initial weight 9.32 ± 1.72 kg) were randomly divided into five groups with six lambs in each group. The control group did not add anything but the basic diet mainly composed of Pennisetum and Corn, and the other four groups added 2, 4, 6 g/kg tea polyphenols and 50 mg/kg chlortetracycline to the basic diet, respectively. The experiment lasted for 42 days.

Results

Dietary tea polyphenols improved the growth and stress response and reduced intestinal permeability of lambs (p > 0.05), while CTC did not affect the final lamb weight (p > 0.05). Both tea phenols and CTC significantly reduced inflammatory factors and enhanced the immune system (p > 0.05). Dietary tea polyphenols increased villus height, villus height/crypt depth, secretory immunoglobulin A (p > 0.05), and antioxidant enzymes, while decreasing MDA and apoptosis in the intestine (p > 0.05). However, compared with other groups, the content of T-AOC in jejunum did not change significantly (p > 0.05). Tea polyphenols also increased claudin-1 levels in the duodenum, jejunum, and ileum more than CTC (p > 0.05). CTC had a limited effect on the mRNA expression of Occludin and ZO-1, while tea polyphenols increased these in both the duodenum and ileum (p > 0.05).

Conclusion

This study demonstrated that tea polyphenols can effectively improve the intestinal barrier of weaned lambs, and that they have anti-inflammatory and antioxidant effects similar to those of antibiotics. Thus, tea polyphenols could be used to replace antibiotics in ensuring safety of livestock products and in achieving the sustainable development of modern animal husbandry.

Grape Pomace: Agrifood By-Product with Potential to Enhance Performance, Yolk Quality, Antioxidant Capacity, and Eggshell Ultrastructure in Laying Hens

Grape pomace (GP) is an industrial by-product of grape juice making and is commonly discarded as a waste product, even with its large quantity of phytochemicals. Thus, the objectives of this trial were to examine the effects of graded dietary GP on laying rate, egg quality, yolk lipid profile, oxidative stability, shell quality and ultrastructure, and serum biochemistry. Two hundred 35-week-old laying hens were allocated to four dietary treatments with ten replicates each. Four diets were formulated by mixing a standard basal diet with GP at 0 g/kg (control), 30 g/kg (GP_3%), 60 g/kg (GP_6%), and 90 g/kg (GP_9%). Egg production percent, egg weight, and egg mass were linearly improved (p < 0.01) due to adding GP to the diets of laying hens. Eggs obtained from laying hens fed with GP diets had (p < 0.01; linear, p < 0.01) greater Haugh units, yolk color, albumen index, and yolk index than those of the control. The GP_9% group had the greatest values (p < 0.05) for shell weight, thickness, and breaking strength. Electron microscopy scanning of eggshells indicated that the incremental dietary level of GP linearly augmented the thickness of the palisade layer but reduced both the mammillary layer and mammillary knob width (p < 0.01). Improved tibia-breaking strength and ash content were shown (p < 0.05) in the GP-fed laying hens. The dietary addition of GP by up to 90 g/kg linearly (p < 0.01) mitigated lipid oxidation and improved the antioxidant capacity in both the serum and stored eggs. A reduction in the percentages of saturated fatty acids was observed, while the contents of monounsaturated fatty acids, polyunsaturated fatty acids, and n-3 fatty acids were augmented because of increasing dietary GP levels (p < 0.001). Additionally, the eggs obtained from laying hens fed on the GP_6% and GP_9% had lower yolk cholesterol content (p < 0.001); this effect was confirmed by linear and quadratic responses (p < 0.001). Laying hens on GP diets had lower (p < 0.01) serum hepatic enzymes, cholesterol, triglycerides, and low-density lipoprotein but greater high-density lipoprotein compared to the control. To sum up, the addition of GP in the layers' diets by up to 90 g/kg increased laying performance, enriched the yolk with beneficial fatty acids, enhanced antioxidant potential in yolk lipids, and improved shell quality and ultrastructure.

Unraveling the Potential of Orange Pulp for Improving Laying Rate, Egg Quality, Oxidative Stability, Fatty Acids Composition, and Reproductive Tract Morphology of Laying Hens

The current study aimed to demonstrate the effects of dietary dried orange pulp (DOP) on the laying performance, egg quality, antioxidant status, yolk fatty acid composition, serum biochemistry, and reproductive tract morphology of laying hens. A total of 200 Lohman Brown Lite laying hens were randomly allotted into 4 dietary treatments with 10 replicates each. The experimental treatment groups were the control group, a basal diet containing 50 g DOP/kg feed (DOP_5%), a basal diet containing 70 g DOP/kg feed (DOP_7%), and a basal diet containing 100 g DOP/kg feed (DOP_10%). Data were statistically analyzed by one-way ANOVA following a completely randomized design, and the incremental levels of dietary DOP were tested by orthogonal polynomial contrasts. The body weight gain, feed intake, egg production%, egg weight, egg mass, and feed conversion ratio of laying hens fed the DOP_7% and DOP_10% diets were greater (p < 0.01) than those fed the control diet. Eggs obtained from the DOP_7% and DOP_10% groups had a heavier shell weight% and shell thickness, as well as a greater yolk color score (p < 0.01; linear, p < 0.01). Dietary DOP improved the egg yolk concentrations of PUFA, n-3 PUFA, and n-6 PUFA (linear, p < 0.001; quadratic, p < 0.05), whereas the content of SFA was reduced (p < 0.001; linear, p < 0.001). The egg yolk cholesterol and triglyceride levels were linearly decreased (p < 0.001) with the inclusion of DOP in the diets of hens. After storage for 40 days, the malondialdehyde (MDA) contents in the egg yolk were reduced, whereas the glutathione peroxidase content was increased (p < 0.01) due to dietary DOP. The DOP_7% and DOP_10% hens had an obvious reduction in the levels of serum total lipids, total cholesterol, triglycerides, low-density lipoprotein, and MDA, whereas high-density lipoprotein and GPx levels were increased (p < 0.01) compared with those fed the control diet. The relative weights of the ovary, oviduct, uterus, and follicle of hens receiving diets containing 7% and 10% DOP were heavier (p < 0.01) than those of the control hens. Moreover, the number of large yellow follicles was increased (p < 0.001; linear, p < 0.001) in the hens-fed diets containing 7% and 10% DOP. In conclusion, dietary DOP at up to 100 g/kg of feed improves laying performance, health status, antioxidant capacity, egg nutritive value, and egg shelf life in laying hens.

Growth performance, meat quality, and blood characteristics of finisher crossbred pigs fed diets supplemented with different levels of green tea (Camellia sinensis) by-products

Background and Aim

Dietary supplementation with green tea by-product shows special effects on animal parameters. This study aimed to assess the effects of green tea by-products (GTBP) in the diet on some blood parameters, growth performance, and carcass characteristics of finishing pigs and on meat quality, and nutritional composition of pork.

Materials and Methods

One hundred and sixty crossbred pigs with an initial body weight of 65.15 ± 0.38 kg, were distributed into four dietary treatments, with four replicates of 10 pigs each. The dietary treatments were a basal diet (control diet, CON), and three experimental diets (GTBP8, GTBP16, and GTBP24) based on the CON diet supplemented with GTBP at 8, 16, and 24 g/kg of feed. The studied parameters were examined during the experimental period of 10 weeks.

Results

No statistical differences in average daily feed intake, average daily gain, and feed conversion ratio were observed between the diet treatments (p > 0.05). Backfat thickness decreased (linear, p < 0.05) according to the GTBP levels but no other carcass parameters. Meat quality was not influenced by the GTBP levels (p > 0.05). However, pigs fed with GTBP had a decrease in cholesterol content and an increase in crude protein and total omega-3 content of pork compared to the CON diet (p < 0.05). Moreover, dietary supplementation with GTBP significantly decreased plasma cholesterol (p < 0.05), and trends for the decrease in low-density lipoprotein cholesterol and urea nitrogen were observed (linear, p = 0.08).

Conclusion

Up to 24 g/kg GTBP in the diet for finishing pigs does not impair animal performance and makes carcass leaner with softer meat as well as positive effects on cholesterol and fatty acid metabolism. Further experiments are needed to determine the optimal levels of GTBP addition in finishing pig diet to produce higher meat quality.

Effect of Green Tea on Weight Gain and Semen Quality of Rabbit Males

The goal of the current study was to evaluate the action of the green tea plant (Camellia sinensis, L) on male rabbit reproduction and some non-reproductive indexes. Male rabbits were fed either a standard diet (control group) or a diet enriched with green tea powder (experimental groups; E): 5 g (E1) or 20 g (E2) per 100 kg of the milled complete feed mixture. Weight gain, sperm concentration, total and progressive motility, as well as haematological, and biochemical parameters and changes in testicular tissue histomorphology were evaluated. Feeding with green tea, at both tested concentrations, decreased weight gain per week and the total average weight gain compared to the control group (p < 0.05). Furthermore, green tea decreased sperm concentration, motility and progressive motility in the group fed with a lower dose (5 g) of green tea powder (p < 0.05), whilst a higher dose (20 g) was neutral. Some haematological and biochemical indexes, like medium-size cell count (MID), mean corpuscular haemoglobin concentration (MCHC), platelet percentage (PCT), levels of phosphorus (P) and total proteins (TP) were decreased in one or both experimental groups (p < 0.05), whilst the triglyceride level (TG) was increased in the E2 group (p < 0.05). The thicknesses of the testicular seminiferous tubules and epithelial layer were not affected by any concentration of green tea powder (p > 0.05). These observations suggest that green tea in the diet may have an adverse effect on rabbit growth and sperm quality, but their effect may be potentially dose-dependent.

Dietary Flavonoids as Modulators of Lipid Metabolism in Poultry

Flavonoids, naturally-occurring compounds with multiple phenolic structures, are the most widely distributed phytochemicals in the plant kingdom, and are mainly found in vegetables, fruits, grains, roots, herbs, and tea and red wine products. Flavonoids have health-promoting effects and are indispensable compounds in nutritional and pharmaceutical (i.e., nutraceutical) applications. Among the demonstrated bioactive effects of flavonoids are anti-oxidant, anti-inflammatory, and anti-microbial in a range of research models. Through dietary formulation strategies, numerous flavonoids provide the ability to support bird health while improving the nutritional quality of poultry meat and eggs by changing the profile of fatty acids and reducing cholesterol content. A number of such compounds have been shown to inhibit adipogenesis, and promote lipolysis and apoptosis in adipose tissue cells, and thereby have the potential to affect fat accretion in poultry at various ages and stages of production. Antioxidant and anti-inflammatory properties contribute to animal health by preventing free radical damage in tissues and ameliorating inflammation in adipose tissue, which are concerns in broiler breeders and laying hens. In this review, we summarize the progress in understanding the effects of dietary flavonoids on lipid metabolism and fat deposition in poultry, and discuss the associated physiological mechanisms.

Green Tea (Camellia sinensis) Products as Alternatives to Antibiotics in Poultry Nutrition: A Review

The overuse and misuse of antibiotics in poultry feeds increase the total cost of production and compromise the quality of poultry products, which poses a serious threat to human health. Globally, health-conscious poultry consumers have long called for the alternate use of natural additives to mitigate the development and spread of multidrug resistant pathogens. Phytogenic plants, such as green tea (Camellia sinensis) products, contain putative nutraceuticals with antibiotic properties that can be used as alternatives to therapeutic, metaphylactic, prophylactic, and growth-promoting antibiotics. However, there are limited studies in the literature that have evaluated the potential of green tea (GT) products when used as replacements to in-feed antibiotics, with most studies focusing on their potential as sources of dietary nutrients in poultry feeds. Thus, this review paper discusses the potential of GT products to replace various antibiotics in poultry diets while presenting GT bioactive substances that can improve the growth performance, carcass and meat quality traits, and health status of the birds. We postulate that the utilisation of GT products in place of antibiotics could deliver sustainable, organic poultry production systems that would contribute significantly to global food and nutrition security.

Growth Performance, Antioxidant Activity, Immune Status, Meat Quality, Liver Fat Content, and Liver Histomorphology of Broiler Chickens Fed Rice Bran Oil

Simple Summary

There are numerous approaches for enrichment of broiler’s meat with valuable nutrients, for instance the enrichment with polyunsaturated fatty acids (PUFA). The addition of vegetable oils in the diets of broilers is an appropriate strategy to enrich the chicken meat with beneficial FA, however, this enrichment is accompanied by a lipid peroxidation with a resultant decrease in the nutritional value, quality, and shelf-life of the meat, and for that reason, the dietary supplementation with antioxidants becomes necessary. What places rice bran oil (RBO) on top of other vegetable oils is its antioxidant components and unique fatty acid profile and it is reported to induce substantial lipid-reducing effects and antioxidant properties. Therefore, this study was performed to determine the influence of RBO inclusion in the diets of broiler chickens on performance, carcass characteristics, blood parameters, meat quality, antioxidant activity, liver lipid content, and liver histological structure. RBO inclusion had a positive effect on the growing performance, dressing percentage, and immune status. Furthermore, RBO supplementation decreased the abdominal fat yield and EE content in the meat, while it increased the content of PUFA in the meat, which may be beneficial for consumers. RBO improved the antioxidant capacity of the meat and the liver, whereas it reduced the concentration of cholesterol and triglycerides in the blood, meat and liver. RBO could be used as an efficient ingredient in broiler chickens’ diets to improve performance, immune status, antioxidant activity, blood lipid profile, and the nutritive value of meat.

Abstract

This trial was performed to determine the effect of rice bran oil (RBO) inclusion in diets of broiler chickens on performance, carcass characteristics, blood parameters, meat quality, antioxidant activity, liver lipid content, and liver histological structure. The 35-day feeding trial was conducted on 240 one-day-old Ross 308 broiler chickens, allocated to four treatment groups with six replicates each. RBO was examined at different inclusion levels, 0% (control), 1% (RBO_1%), 1.5% (RBO_1.5%), and 2% (RBO_2%) in a completely randomized design. The results showed that at the end of the trial (35 days) the RBO supplementation had positive effects (p < 0.001) on the productivity parameters, but the feed intake was linearly decreased due to RBO inclusion. In addition, RBO supplementation linearly improved (p < 0.05) the dressing percentage, breast yield, immune organs relative weights, and meat glutathione concentration, while it decreased (p < 0.01) the abdominal fat yield and meat crude fat, triglycerides, cholesterol, and Malondialdehyde (MDA) contents in broiler’s meat. Moreover, serum total protein, globulin, and high-density lipoprotein contents improved noticeably (p < 0.01) due to offering an RBO-supplemented diet, but serum total lipids, total cholesterol, triglyceride, low-density lipoprotein, and aspartate aminotransferase concentrations linearly reduced (p < 0.01). The RBO supplementation augmented (p < 0.05) the phagocytic index, phagocytic activity, and antibody titer compared to control. On the other hand, RBO inclusion had no effect on the breast, thigh, or abdominal fat color parameters. Moreover, RBO supplementation reduced (p < 0.01) the content of total saturated FA (SFA), but increased (p < 0.01) the content of total monounsaturated FA (MUFA), and polyunsaturated FA in both breast and thigh meat. Chemical analysis of the liver tissue samples revealed that the inclusion of RBO linearly reduced (p < 0.05) hepatic cholesterol, triglyceride, and MDA contents. Histologically, the lipid percentage and number of lipid droplets (p < 0.01) were markedly lessened in the RBO-supplemented groups. The histological structure of the liver asses by light and electron microscope were normal in all groups without any pathological lesions. It is concluded that RBO could be used as a valuable ingredient in broiler chickens’ diets to stimulate the growing performance and immune status, enhance the antioxidant activity and blood lipid profile, augment liver function, and improve the nutritive value of the meat.

Maximum levels of cross-contamination for 24 antimicrobial active substances in non-target feed. Part 12: Tetracyclines: tetracycline, chlortetracycline, oxytetracycline, and doxycycline

The specific concentrations of tetracycline, chlortetracycline, oxytetracycline and doxycycline in non-target feed for food-producing animals, below which there would not be an effect on the emergence of, and/or selection for, resistance in bacteria relevant for human and animal health, as well as the specific antimicrobial concentrations in feed which have an effect in terms of growth promotion/increased yield were assessed by EFSA in collaboration with EMA. Details of the methodology used for this assessment, associated data gaps and uncertainties are presented in a separate document. To address antimicrobial resistance, the Feed Antimicrobial Resistance Selection Concentration (FARSC) model developed specifically for the assessment was applied. The FARSC for these four tetracyclines was estimated. To address growth promotion, data from scientific publications obtained from an extensive literature review were used. Levels in feed that showed to have an effect on growth promotion/increased yield were reported for tetracycline, chlortetracycline, oxytetracycline, whilst for doxycycline no suitable data for the assessment were available. Uncertainties and data gaps associated with the levels reported were addressed. It was recommended to perform further studies to supply more diverse and complete data related to the requirements for calculation of the FARSC for these antimicrobials.

The Effect of Green Tea (Camellia sinensis) Leaf Powder on Growth Performance, Selected Hematological Indices, Carcass Characteristics and Meat Quality Parameters of Jumbo Quail

Green tea leaves contain a wide range of active bio-compounds that are essential for sustainable quail intensification; however, its feed value is not known for the Jumbo quail. Therefore, this study evaluated the effect of different levels of green tea leaf powder (GTLP) on physiological and meat quality parameters of the Jumbo quail. One-week-old chicks (n = 350; 56.1 ± 2.12 g live-weight) were evenly distributed to 35 replicate pens and reared on five experimental diets formulated as follows: a standard grower diet with zinc-bacitracin (PosCon), a standard grower diet without zinc-bacitracin (NegCon), and NegCon diet treated with 10 (GT10), 25 (GT25) and 50 g/kg (GT50) of GTLP. Weight gain linearly decreased in week 2 but increased in week 4, whereas feed conversion efficiency linearly declined in weeks 2 and 3 as GTLP levels increased. Overall feed intake, carcass yield, and caecum and colon weights showed a linear increase with GTLP levels. Hematological parameters fell within the normal ranges reported for healthy quail. The GT10 group showed larger liver weights than the PosCon and NegCon groups. It was concluded that dietary inclusion of GTLP enhances overall feed intake and carcass performance but not feed efficiency, hematological and meat quality parameters of Jumbo quail.

Green tea dietary supplementation in broiler chickens: Effect on the development of chicken intestine

This experiment explored the dietary effects of green tea (Camellia sinensis) in feed supplementation on the development of broiler chicks. Totally, two hundred and seventy-day-old male broiler chicks were assigned to 27 broiler groups each with 10 individuals (initial mean body weight 44.2 ± 1.3 g) in a 4 × 2 factorial arrangement. Each chicken group was supplemented with the feed additives of green tea powder. The trial data were measured and obtained based on the records of carcass traits and intestine characteristics of broiler chicken fed with four different additive levels of green tea (0.25%, 0.50%, 0.75%, and 1.00%). The experiment lasted for two trial periods of 21 days and 42 days for each treatment of the green tea supplement with full records of broiler traits. There were interesting results recorded in the majority of broiler intestinal traits between the two trial periods. There are a few significant differences (p < .05) observed among multiple comparisons of some intestinal traits in broiler chicks such as colon diameter (p = .022) and jejunum width (p = .01). The most significant differences exist in these intestinal traits of chicken right and left cecum among broiler chicks fed with dietary green tea powder (p < .05). The other intestinal characteristics of broiler chicks were recorded from single treatment are insignificantly distinguished compared with the control groups. There are also some near significant differences of chicken intestinal carcass traits and characteristics. These results and experimental data of this study extend the current knowledge on the dietary effects of green tea in chicken raising and feeding with dietary supplementation.

Impact of Dietary Supplementation with Moringa oleifera Leaves on Performance, Meat Characteristics, Oxidative Stability, and Fatty Acid Profile in Growing Rabbits

Simple Summary

Rabbit meat is mostly preferred by consumers owing to its high nutritive value and potential health benefits. However, rabbit meat is commonly more prone to lipid peroxidation during storage, with negative effects on quality traits of meat, due to its elevated level of unsaturation of fatty acids. Moringa oleifera leaves have gained great interest owing to their high nutritional value and low anti-nutritional factors. Moringa oleifera leaves could possibly avoid oxidation damage and exhibit antioxidant activities that can conquer free radicals and reactive oxygen species synthesis. Therefore, the objective of the current study was to evaluate the effects of feeding Moringa oleifera leaves on performance, carcass characteristics, antioxidant capacity, blood biochemical constituents, meat quality, and fatty acids profile of growing rabbits. Moringa oleifera leaves supplementation improved weight gain, feed conversion ratio, antioxidant status, and meat quality characteristics. Dietary Moringa oleifera leaves supplementation enhanced PUFA contents, n-3 fatty acid, crude protein, and color of meat, but lowered the relative content of ether extract of the meat. Our findings suggested that Moringa oleifera could be used at a level of 1.5 g/kg of the growing rabbits’ diets with beneficial impacts on performance and the nutritional value of the meat.

Abstract

Moringa oleifera leaves (MOL) have gained great interest as a non-traditional feed ingredient due to their unique nutritional value. Therefore, the objective of the current study was to evaluate the effects of graded dietary supplementation levels with MOL on performance, carcass characteristics, antioxidant capacity, blood biochemical constituents, meat quality, and fatty acids profile of growing rabbits. A total of 120 weaned New Zealand white rabbits (6 weeks old) were randomly allotted into 4 dietary groups with 5 replicates each (n = 6), which were fed for 42 days with a basal diet as control or 3 experimental diets supplemented with 5, 10, or 15 g/kg MOL. The results showed that, compared to the control group, the dietary inclusion of MOL at a level of 10 and 15 g/kg DM linearly increased (p < 0.01) final live weight (2403.3 and 2498.2 vs. 2166.6) and average daily weight gain (36.5 and 35.51 g/d vs. 28.72 g/d), and enhanced feed conversion ratio (2.49 and 2.50 vs. 3.14). The dietary supplementation with MOL linearly increased dressing out percentage, spleen index, intestinal length, and decreased abdominal fat index (p < 0.01). Greater serum levels of total protein and globulin, but lower alanine aminotransferase and aspartate aminotransferase were observed in the MOL-fed rabbits (p < 0.01). Serum levels of total triglycerides, cholesterol, and low-density lipoprotein (p < 0.05) were decreased linearly and quadratically in the MOL groups compared with the control. Glutathione peroxidase activity increased (p < 0.01), whereas malondialdehyde decreased (p < 0.01) linearly and quadratically in both serum and meat, in response to dietary MOL supplementation. Dietary MOL supplementation increased the meat crude protein content but lowered the relative content of ether extract in the meat (p < 0.05). The relative content of the meat n-3 PUFA was increased by about 33.71%, 29.46%, and 24.36% for the MOL_0.5%, MOL_1%, and MOL_1.5% groups compared to control. In conclusion, MOL could be used at a level of 1.5g/kg of the growing rabbits’ diets with beneficial impacts on performance, antioxidant capacity, and the nutritional value of the meat.

Effects of dietary supplementation with Taiwanese tea byproducts and probiotics on growth performance, lipid metabolism, and the immune response in red feather native chickens

Objective

This study compared the catechin composition of different tea byproducts and investigated the effects of dietary supplementation with green tea byproducts on the accumulation of abdominal fat, the modulation of lipid metabolism, and the inflammatory response in red feather native chickens.

Methods

Bioactive compounds were detected, and in vitro anti-obesity capacity analyzed via 3T3-L1 preadipocytes. In animal experiments, 320 one-day-old red feather native chickens were divided into 4 treatment groups: control, basal diet supplemented with 0.5% Jinxuan byproduct (JBP), basal diet supplemented with 1% JBP, or basal diet supplemented with 5×10⁶ colony-forming unit (CFU)/kg Bacillus amyloliquefaciens+5×10⁶ CFU/kg Saccharomyces cerevisiae (BA+SC). Growth performance, serum characteristics, carcass characteristics, and the mRNA expression of selected genes were measured.

Results

This study compared several cultivars of tea, but Jinxuan showed the highest levels of the anti-obesity compound epigallocatechin gallate. 3T3-L1 preadipocytes treated with Jinxuan extract significantly reduced lipid accumulation. There were no significant differences in growth performance, serum characteristics, or carcass characteristics among the groups. However, in the 0.5% JBP group, mRNA expression of fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC) were significantly decreased. In the 1% JBP group, FAS, ACC and peroxisome proliferator-activated receptor γ levels were significantly decreased. Moreover, inflammation-related mRNA expression levels were decreased by the addition of JBP.

Conclusion

JBP contained abundant catechins and related bioactive compounds, which reduced lipid accumulation in 3T3-L1 preadipocytes, however there was no significant reduction in abdominal fat. This may be due to a lack of active anti-obesity compounds or because the major changes in fat metabolism were not in the abdomen. Nonetheless, lipogenesis-related and inflammation-related mRNA expression were reduced in the 1% JBP group. In addition, dietary supplementation with tea byproducts could reduce the massive amount of byproducts created during tea production and modulate lipid metabolism and the inflammatory response in chickens.

L-theanine: an astounding sui generis amino acid in poultry nutrition

L-theanine (γ-Glutamylethylamide) is a nonprotein water soluble amino acid (AA) mostly found in leaves of Camellia sinensis (green tea). This is a key component of green tea and is considered as the most abundant form of total AAs in green tea (i.e., about 50%). L-theanine is an exclusive taste ingredient of tea producing an attractive flavor and aroma in tea. It has biological effects such as antioxidant, growth promoter, immune booster, anti-stresser, hepatoprotective, antitumor, antiaging, antimicrobial, anti-inflammatory, and antianxiety activities that are worth noticing. It could reduce the oxidative impairment by reducing the synthesis of reactive oxygen species, oxidative parameters, and lipid damage as well as increasing the activity of antioxidant enzymes. The oral ingestion of L-theanine enhanced γδ T-cell proliferation. Therefore, it is being considered an essential compound of green tea that has the ability to improve immune function. The L-theanine can be used as a potential treatment for hepatic injury and immune-related liver diseases via the downregulation of the inflammatory response through the initiation of nitric oxide synthesis and glutathione production which are likely to be critical for the control of hepatic diseases as well as for the improvement of immune function. In addition, it could be used as a best natural feed additive with a potent antistressor by decreasing the levels of corticosterone, dopamine, and noradrenaline. After systematically reviewing the literature, it is noticed that most studies were carried out on mice, pig, human, and butterfly; while dietary supplementation studies of L-theanine in animal and poultry especially among broilers are very limited because of less awareness of this AA. So, the aim of this review is to encourage the veterinarian and poultry researchers to conduct more research at the molecular level about this AA to expose its more beneficial effects and its mechanism of absorption for potential use of this unique green tea AA in poultry nutrition.

Effects of Fermented Tea Residue on Fattening Performance, Meat Quality, Digestive Performance, Serum Antioxidant Capacity, and Intestinal Morphology in Fatteners

Simple Summary

Tea residue is the remaining residue of tea after drinking or deep processing. With the annual consumption of tea, a large amount of discarded tea residue is produced. If the tea residue is not effectively utilized, it will cause not only environmental pollution, but also represent a waste of resources. In this study, strains of Bacillus subtilis, Aspergillus niger, and Saccharomyces cerevisiae were used to produce fermented tea residue (FTR). Different levels of FTR were used instead of corn and soybean meal. The resulting product was used to feed pigs bred for rapid growth, also known as fatteners. We explored its effects on growth performance, digestion performance, meat quality, serum antioxidant capacity, and intestinal morphology in fatteners. The aim is to provide a scientific basis for the future use of FTR as a feed material.

Abstract

This study investigated the dietary supplementation of tea residue fermented by Bacillus subtilis, Aspergillus niger, and Saccharomyces cerevisiae, to explore its effects on growth performance, digestion performance, meat quality, serum antioxidant capacity, and intestinal morphology in pigs bred for rapid growth, also known as fatteners. One hundred and ninety-two healthy “Duroc × Landrace × Yorkshire” ternary hybrid pigs (body weight 70 ± 1.0 kg) were randomly divided into four groups according to the feeding test requirements, with four replicates in each group, and 12 fatteners per replicate. The control group (CG) was fed the basal diet. Treatments 1 (T1), 2 (T2), and 3 (T3), comprising ratios of 10%, 15%, and 20% of tea residue were added to the basal diet. The test period was 60 days. The results showed that supplementation of FTR in fatteners’ diets increased final body weight (FBW), average daily gain (ADG), and feed conversion ratio (FCR) in the T1 and T2 groups (p < 0.05). Compared with the other groups, the lightness (L*) and pH were significantly affected in the T2 group (p < 0.05). Compared with the CG, dietary supplementation of FTR significantly increased the nutrient digestibility of crude protein (CP), ether extract (EE), calcium (Ca), and phosphorus (P), improved the lipase and trypsin activities, and reduced drip loss and the shear force of fatteners (p < 0.05). Glutathione peroxidase (GSH-Px) and total antioxidant capacity (T-AOC) were significantly increased in the T2 and T3 groups compared with the other groups (p < 0.05). Supplementation of FTR in the jejunum significantly increased the villi height of the T2 group and the ratio of villi height to crypt depth of the FTR groups. Compared with the other two groups, the T2 and T3 groups significantly reduced the ratio of the villous height to crypt depth in the duodenum (p < 0.05). In conclusion, the tea residue after fermentation was shown to have beneficial effects on the fattening performance, digestion performance, meat quality, serum antioxidant capacity, and intestinal morphology of fatteners.

Nutritional applications and beneficial health applications of green tea and l-theanine in some animal species: A review

Green tea (Camellia sinensis) is a popular herbal plant with abundant health benefits, and thus, it has been used as a potent antioxidant for a long time. Based on the available literature, the diversity and the availability of multifunctional compounds in green tea offer its noteworthy potential against many diseases such as liver and heart diseases, inflammatory conditions and different metabolic syndromes. Owing to its bioactive constituents including caffeine, amino acids, l-theanine, polyphenols/flavonoids and carbohydrates among other potent molecules, green tea has many pharmacological and physiological effects. The effects of green tea include anti-oxidative, anti-inflammatory, anti-arthritic, anti-stress, hypolipidaemic, hypocholesterolaemic, skin/collagen protective, hepatoprotective, anti-diabetic, anti-microbial, anti-infective, anti-parasitic, anti-cancerous, inhibition of tumorigenesis and angiogenesis, anti-mutagenic, and memory and bone health-improving activities. Apart from its utilization in humans, green tea has also played a significant role in livestock production such as in dairy, piggery, goatry and poultry industries. Supplementation of animal feeds with green tea and its products is in line with the modern concepts of organic livestock production. Hence, incorporating green tea or green tea by-products into the diet of poultry and other livestock can enhance the value of the products obtained from these animals. Herein, an effort is made to extend the knowledge on the importance and useful applications of green tea and its important constituents in animal production including poultry. This review will be a guideline for researchers and entrepreneurs who want to explore the utilization of feeds supplemented with green tea and green tea by-products for the enhancement of livestock production.

Effects of Supplementation of Branches and Leaves Trimmed from Tea Plant on Growth Performance, Rumen Fermentation and Meat Composition of Nanjiang Yellow Goats

Simple Summary

The effects of supplementation of branches and leaves trimmed from tea tree (BLTT) on growth performance, rumen fermentation characteristics and meat composition of fattening Nanjiang Yellow goats were studied. Supplementation of 4% BLTT increased final body weight of goats and also increased the activity of superoxide dismutase, while glutathione peroxidase and malondialdehyde followed the quadratic curve. Quadratic curves were also observed for villus height, crypt depth and the ratio of villus height to crypt depth in the jejunum. The quadratic effect was obtained for total essential amino acids, and individual amino acids threonine and leucine. Supplementation of 4% BLTT decreased the saturated fatty acid C16:0, and a quadratic effect was observed for polyunsaturated fatty acid C18:3 (n−3). From the present study, it is concluded that BLTT supplementation has a positive effect on body antioxidative status, gastrointestinal development, rumen fermentation characteristics and overall hence growth performance and meat composition in goats.

Abstract

Thirty-two 6-month-old, healthy Nanjiang Yellow goats (34.6 ± 4.16 kg) were randomly divided into four treatments to evaluate the supplementary effects of branches and leaves trimmed from tea tree (BLTT) on growth performance, rumen fermentation characteristics, and meat composition in fattening goats. The control goats were fed a basal diet. Treatments 1, 2 and 3 were fed 2%, 4% and 6% of BLTT respectively. After a 60 d feeding trial, blood samples were collected for the analysis of the antioxidant profile and goats were slaughtered to obtain the rumen fluid and carcass samples for determination of rumen fermentation characteristics and meat composition perameters. Increased final body weight was observed in goats fed 4% BLTT compared with control. The activity of superoxide dismutase was increased in the 4% BLTT-treated group, while glutathione peroxidase and malondialdehyde followed the quadratic curve. Quadratic curves were also observed for villus height, crypt depth and the ratio of villus height to crypt depth in the jejunum. The quadratic effect was obtained for total essential amino acids, and individual amino acids threonine and leucine. The saturated fatty acid C16:0 was decreased with 4% of BLTT supplementation, and a quadratic effect was observed for polyunsaturated fatty acid C18:3 (n−3). To sum up, our findings revealed that BLTT supplementation has a positive effect on body antioxidative status, gastrointestinal development, rumen fermentation characteristics and overall growth performance and meat quality in goats.

Green tea can supress rabbit ovarian functions in vitro and in vivo

The aim of present study was to evaluate the action of green tea and its constituents on rabbit ovarian functions and some non-reproductive indexes. In in vitro experiments, rabbit ovarian fragments were cultured with green tea constituents - epigallocatechin-3-gallate (EGCG), green tea polyphenols (GTPP) and resveratrol (RSV) (at 0, 1, 10 or 100 μg/mL medium). The accumulation of an apoptosis marker - caspase 3 and the release of progesterone (P4) and testosterone (T) were measured. In in vivo experiments, does were fed a standard diet or a diet enriched with green tea powder. The weight gain, mortality, ovarian length and weight, conception and kindling rate, number of liveborn, stillborn, and weaned pups, diameter of ovarian follicles and some blood haematological and biochemical parameters were analysed. Culture of ovarian fragments with EGCG increased accumulation of caspase 3, whilst both GTTP and RSV decreased it. EGCG inhibited both P4 and T output, GTPP stimulated P4 and inhibited T, whilst RSV promoted release of both P4 and T. Feeding with green tea increased ovarian length and diameter of ovarian non-ovulated peri-ovulatory haemorrhagic but not of primary and secondary growing follicles. Furthermore, green tea reduced conception and kindling rate, the number of liveborn and weaned pups, increased female mortality but not their weight gain. It reduced platelet distribution width, but it did not affect other haematological and biochemical indexes. These observations suggest that dietary green tea can reduce rabbit doe's viability, ovarian functions and fecundity, perhaps due to changes in ovarian cell apoptosis, steroid hormones release and blockade of the ovulation of large ovarian follicles. The anti-reproductive action of green tea could be due to its constituent - EGCG with pro-apoptotic and anti-steroid hormone properties.

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.

Effect of amount and duration of waste green tea powder on the growth performance, carcass characteristics, blood parameters, and lipid metabolites of growing broilers

This study has evaluated the possible effect of waste powder of green tea (Camellia sinensis) in feed supplementation on the growth performance, carcass characteristics, blood parameters, and lipid metabolites of growing broilers (chicks) in both the amount and duration aspects of dietary additives during the finisher phases. In the experiment, growth performance, carcass characteristics, blood parameters, and lipid metabolites of broiler chicks have been fully recorded and explored. The diet of 271 day-old Ross 308 male broiler chicks has been supplemented with 0, 0.25, 0.50, 0.75, and 1.00% (w/w) green tea powder in addition to normal feeding additives. The experiment lasted for 21 and 42 days, respectively, for each value of the green tea supplement and for separate groups of animals. Broiler feed has been supplemented with different levels of green tea powder to assess the trial effect and potential beneficial dose on selected growth performance, carcass characteristics, and blood parameters of broiler chicks. Although there are almost no differences of broiler parameters and characteristics measured from one point of view of single treatment factor (amount or duration), against the control groups during the three trial periods, the overall effect of amount and duration of feeding green tea powder is positive on growth performance, carcass characteristics, blood parameters, and lipid metabolites of growing broilers, although there are nearly no differences in some broiler parameters and characteristics. However, there are a remarkable interactive effect of amount and duration of different feeding levels of green tea powder and obvious differences observed in all the parameters and characteristics of growing broilers. Especially, usage of feeding green tea powder largely decreased the abdominal fat content and some lipid metabolites, including VLDL cholesterol, LDL cholesterol, triglycerides, and AST of broiler chicks. While additional data are still needed to evaluate and analyze the optimum supplement feed doses, it can be concluded that dietary green tea is a positive feed supplementation to reduce abdominal fat and lipid metabolites and induce antioxidants.

Effect of catechins on fattening performance, meat quality, some antioxidant and blood parameters and fattening costs in Japanese quail (Coturnix coturnix japonica)

The aim of this study was to investigate the effect of dietary supplementation of green tea (Camellia sinensis) catechins in quail (Coturnix coturnix japonica). Quail were fed with a basal diet, and the treatment groups were fed on the basal diet with 1.25 or 2.50 g/kg catechin supplementation for 30 d. Fattening performance and meat quality of the quail were estimated. Serum total antioxidant status (TAS), plasma and liver malondialdehyde (MDA) and some serum biochemical parameters were measured. The results showed that catechin supplementation did not affect live weight, feed intake, feed conversion ratio, carcass weight, carcass dressing or the nutrient composition of breast and thigh meats. The water holding capacity (WHC) of breast meat was increased in the 2.50 g/kg catechin treatment. Catechin supplementation increased the serum TAS, but decreased plasma MDA and liver MDA concentration as well as serum glucose and total cholesterol levels. Serum triglyceride and total protein levels were not affected by catechin supplementation. In conclusion, catechins have effective antioxidant hypoglycaemic and hypocholesterolaemic properties, as well as having the potential to increase meat quality in fattening quail. On the other hand, catechin supplementation did not have any negative effect on the fattening performance, meat nutrient composition and fattening costs in fattening quail.

Heterogeneous photodegradation of methylene blue with iron and tea or coffee polyphenols in aqueous solutions

Recently, we developed two new Fenton catalysts using iron (Fe) and spent tea leaves or coffee grounds as raw material. In this study, Fe-to-tea or Fe-to-coffee polyphenol complexes were successfully tested as heterogeneous photo-Fenton catalysts. The photodegradation efficiency of methylene blue solutions with Fe-to-polyphenol complexes was higher than that of homogeneous iron salts in the photo-Fenton process. Furthermore, the tested Fe-to-polyphenol complexes could be reused by simply adding H2O2 to the solutions. After three sequential additions of H2O2, the conventional catalysts FeCl2·4H2O and FeCl3 removed only 16.6% and 53.6% of the dye, while the catalysts made using spent coffee grounds and tea leaves removed 94.4% and 96.0% of the dye, respectively. These results showed that the complexes formed between Fe and chlorogenic acid, caffeic acid, gallic acid and catechin, which are the main polyphenols in tea and coffee, can be used to improve the photo-Fenton process.

Seamustard (Undaria pinnatifida) Improves Growth, Immunity, Fatty Acid Profile and Reduces Cholesterol in Hanwoo Steers

The study was designed to evaluate the effect of 2% seamustard (Undaria pinnatifida) by-product (SW) on growth performance, immunity, carcass characteristics, cholesterol content and fatty acid profile in Hanwoo steers. A total of 20 Hanwoo steers (ave. 22 months old; 619 kg body weight) were randomly assigned to control (basal diet) and 2% SW supplemented diet. Dietary SW supplementation significantly (p<0.05) improved average daily gain and gain:feed ratio as well as serum immunoglobulin G concentration. Chemical composition and quality grade of meat and carcass yield grades evaluated at the end of the trial were found to be unaffected by SW supplementation. Dietary SW significantly reduced meat cholesterol concentration (p<0.05). Dietary SW supplementation significantly reduced the myristic acid (C14:0) and palmitoleic acid (C16:ln-7) concentration, while SW increased the concentration of stearic acid (C18:0) and linolenic acid (C18:3n-3) compared to control (p<0.05). Dietary SW supplementation had no effect on saturated fatty acids (SFA), unsaturated fatty acids, poly unsaturated fatty acid (PUFA) or mono unsaturated fatty acid content in muscles. A reduced ratio of PUFA/SFA and n-6/n-3 were found in SW supplemented group (p<0.05). In conclusion, 2% SW supplementation was found to improve growth, immunity and fatty acid profile with significantly reduced cholesterol of beef.

Evaluation of fermented Alisma canaliculatum with probiotics as potential feed additives for finishing Hanwoo (Bos taurus coreanae) steers

The present study was conducted to develop a functional feed additive, Alisma canaliculatum probiotic (ACP), for beef cattle, using the medicinal plant Alisma canaliculatum along with probiotic strains. A three-step fermentation process was developed for the manufacture of ACP. The effects of dietary ACP on growth performance, carcass characteristics, meat composition and oxidative stability in Hanwoo steers were investigated. Twenty-four Hanwoo steers (average 592.91 ± 10 kg bodyweight) were randomly assigned to three dietary treatments: control (basal diet), ACP 0.5% (basal diet + 0.5% ACP) and ACP 1.0% (basal diet + 1.0% ACP). Overall, dietary ACP resulted in significant elevation of bodyweight gain and feed efficiency compared with the control (P < 0.01). No significant differences in carcass characteristics were found among the dietary treatments, although carcass quality grade was improved by the ACP 0.5% diet (P = 0.007). Moisture, crude ash and crude protein contents were unaffected; however, crude fat and cholesterol contents were lower in steers fed ACP 0.5% (P < 0.05). Whereas the calcium of Hanwoo beef was unaffected by the dietary treatments, iron and magnesium contents were elevated by the ACP 0.5% diet compared with the control or ACP 1.0% diet (P < 0.01). Further, the ACP 0.5% diet improved the meat fatty acid profile by reducing saturated fatty acid content, especially myristic acid (P ≤ 0.05), as well as by increasing unsaturated fatty acid and n-3 polyunsaturated fatty acid content, especially α-linolenic acid (P < 0.10). The ACP diet was found to have positive effects on unsaturated fatty acid/saturated fatty acid and n-6/n-3 ratios (P ≤ 0.05). Thiobarbituric acid reactive substance values of the control group were higher compared with either of the ACP diet groups (P < 0.001). Overall, these data indicate that dietary ACP conferred beneficial effects on the growth performance, fatty acid profile, meat composition and oxidative stability in Hanwoo steers. Therefore, ACP may be used as a feed additive for beef cattle.

Evaluation of green tea by-product and green tea plus probiotics on the growth performance, meat quality and immunity of growing–finishing pigs

The present study was conducted to evaluate the effects of green tea by-product (GTB) and green tea plus probiotics (GT+P) on the growth performance, carcass characteristics, meat quality, blood parameters and immunity of growing–finishing pigs. In total, 80 crossbreed growing pigs were assigned to receive four dietary treatments for a period of 8 weeks. The dietary treatments were a basal diet (control), basal diet supplemented with 0.003% chlortetracycline (antibiotic), basal diet with 0.5% GTB (GTB) and basal diet containing 0.5% GT+P (GT+P). The results of our study indicated that bodyweight gain increased (P < 0.05) in response to the addition of GT+P to the basal diet. Crude protein and crude ash content, and shear values of loin meat were significantly (P < 0.05) increased in the GT+P group, although moisture and juiciness were decreased (P < 0.05). The GTB group had higher (P < 0.05) serum glucose concentrations, whereas the GT+P exhibited lower (P < 0.05) insulin concentrations. The values of thiobarbituric acid-reactive substances of fresh loin meat and meat that had been preserved for 1 week were lower (P < 0.05) in the GT+P group than those of the control and GTB groups. The growth of spleen cells incubated in concanavalin A (Con A) and lipopolysaccharide (LPS) medium was statistically higher (P < 0.05) for the GT+P group than for the GTB or antibiotic group. IL-6 and TNF-α production by spleen cells induced by Con A and LPS was increased in the GTB and GT+P group (P < 0.05) compared with the antibiotic group. Taken together, the results of the present study indicated that GT+P exerts positive effects on weight gain, meat composition, blood parameters and immunity in pigs, and could be used as an alternative to antibiotics for growing–finishing pig feeds.

Dietary strategies to improve nutritional value, oxidative stability, and sensory properties of poultry products

Consumers demand both safer and more nutritious food products exempt of non-natural origin preservatives or other food additives. In this frame, products with lower fat content and/or a higher ratio in unsaturated fatty acids, especially n-3 fatty acids, are desired because these lipids can help prevent the development of cardiovascular and inflammatory pathologies. The intake of meat products is of interest because they are an excellent source of vitamins and minerals. In addition, the shelf-life of meat products can be extended by the presence of natural antioxidants coming from different sources such as plant extracts. Therefore, different strategies have been studied to improve the nutritional value, oxidative stability, and sensory characteristics of meat products and eggs through different mineral and natural dietary supplements. In comparison to other strategies, dietary supplements present the advantage that first the living animals may efficiently distribute the compounds throughout the tissues and second, the dietary supplementation is safer because the resulting enriched meat products and eggs ensure tolerable amounts in humans. Poultry meats and eggs are widely consumed and their fatty acid profile and tocopherol content can be easily modified through different dietary strategies thus being excellent models to improve their nutritional value and oxidative stability.

Epigallocatechin-3-gallate from green tea negatively affects swine granulosa cell function

The use of herbs as additives in livestock nutrition as an alternative to antibiotics is becoming a new goal in animal production. It is known that green tea exerts antimicrobial activity owing to specific flavonoid compounds named catechins, primarily represented by epigallocatechin-3-gallate (EGCG). Remarkably, despite many potential benefits of green tea and EGCG consumption, it is also important to get an insight on the possible reproductive-related consequences of feeding supplementation. To this purpose, granulosa cells were harvested from follicles > 5mm and treated with 5 and 50 microg/ml of EGCG in order to evaluate the effects on the main parameters of granulosa cell function: steroidogenesis, by measuring progesterone and estradiol-17beta production, and proliferation, one of the major feature of ovarian follicular growth. Moreover, as the genesis of new vessels has been demonstrated to be fundamental for follicle development, we evaluated the effect of EGCG on the production of the main angiogenetic factor, VEGF, by swine granulosa cells. Finally, since reactive oxygen species (ROS) might be involved in the control of female reproductive activity, we studied the effect of EGCG on superoxide anion (O2-) and hydrogen peroxide (H2O2) production by swine granulosa cells and on the activity of the scavenging enzyme superoxide dismutase (SOD). EGCG significantly (p < 0.05) inhibited proliferation, steroidogenesis, VEGF and O2- production by swine granulosa cells; on the contrary, H2O2 levels and SOD activity were stimulated (p < 0.05) by the catechin. Therefore, since our data demonstrate that EGCG has a negative effect on reproductive performances in swine, feeding supplementation should be carefully considered.

EGCG, a major component of green tea, inhibits VEGF production by swine granulosa cells

Vascular Endothelial Growth Factor (VEGF) plays a pivotal role in the physiological ovarian angiogenic process: its production appears to be stimulated by the hypoxic environment which takes place during follicle development. Recently, epigallocatechin-3-gallate (EGCG) from green tea has been used in livestock nutrition as an alternative to antibiotics. However, despite many potential benefits of EGCG consumption, it is also important to get an insight on the possible reproductive-related consequences of feeding supplementation: in fact this substance has been found to inhibit angiogenesis, a process fundamental for follicle development. Therefore, we evaluated the effect of EGCG (5 and 50 microg/ml) on the production of the main angiogenetic factor, VEGF, by swine granulosa cells cultured in normoxia (19% O2), partial (5% O2) or total hypoxia (1% O2). In addition, we studied the effect of the catechin on cell proliferation. Our data demonstrate that both partial and total hypoxia stimulated VEGF production. EGCG reduced VEGF production independently of the O2 condition: 50 microM was the most effective doses. Granulosa cell proliferation was inhibited by EGCG even if only by the highest concentration. This effect might possibly be due to the decrease induced in VEGF production. Therefore feeding supplementation with EGCG should be carefully considered.