The effects of replacing wheat and soyabean meal with duckweed (Lemna minor) and including enzymes in the diet of laying hens on the yield and quality of eggs, biochemical parameters, and their antioxidant status.

Duckweed is a rapidly growing aquatic plant, which could be used in the diet of laying hens to enhance carbon capture and improve land use efficiency. Digestion may be improved by supplementation with exogenous enzymes. We replaced soyabean meal and wheat with duckweed in a 10-week study with 432, 60-week-old Hy-Line W-36 layers, divided into six isocaloric and isonitrogenous dietary treatments, each with eight replicates. Two factors were investigated: first, duckweed substituted for wheat gluten meal and soyabean meal at 0, 7.5 and 15% of the diet, and second, with and without a multi-enzyme supplement (500 mg/kg). Duckweed did not affect egg output or weight, but it improved yolk color (P = 0.01) and reduced the liver enzymes aspartate aminotransferase (P = 0.04) and alanine aminotransferase (P = 0.02) in serum, suggesting hepatoprotective effects. Enzyme addition did not alter the effects of including duckweed in the diet, but it increased feed intake (P = 0.03). It is concluded that, as well as offering the potential to increase land productivity, inclusion of duckweed in the diet of laying hens enhances egg yolk color and hepatoprotection, without detrimental effects on performance.

Immunomodulatory Effects of Natural Feed Additives for Meat Chickens.

Broiler chickens are increasingly kept in large numbers in intensive housing conditions that are stressful, potentially depleting the immune system. With the prohibition of the use of antibiotics in poultry feed spreading worldwide, it is necessary to consider the role of natural feed additives and antibiotic alternatives to stimulate the chickens' immune systems. We review the literature to describe phytogenic feed additives that have immunomodulatory benefits in broilers. We initially review the major active ingredients from plants, particularly flavonoids, resveratrol and humic acid, and then describe the major herbs, spices, and other plants and their byproducts that have immunomodulatory effects. The research reviewed demonstrates the effectiveness of many natural feed additives in improving the avian immune system and therefore broiler health. However, some, and perhaps all, additives have the potential to reduce immunocompetence if given in excessive amounts. Sometimes additives are more effective when given in combination. There is an urgent need to determine tolerance levels and optimum doses for additives deemed most suitable to replace antibiotics in the diet of broiler chickens. Effective replacement is most likely with readily available additives, such as olive oil byproducts, olive leaves and alfalfa. It is concluded that effective replacement of antibiotic function with plant-derived additives will be possible, but that further research is necessary to determine optimum doses.

A Comparison of the Effects of Raw and Processed Amaranth Grain on Laying Hens' Performance, Egg Physicochemical Properties, Blood Biochemistry and Egg Fatty Acids.

In order to investigate the effects of using different levels of either raw or processed amaranth (Amaranthus hybridus chlorostachys) grain on performance productivity, egg physicochemical properties, blood biochemistry and egg fatty acids, a trial was conducted using 168 Hy-line W-36 laying hens (67 week of age) in a completely randomized design with seven treatments and six replications of four birds for eight weeks. The trial treatments included the control group receiving no amaranth and the test groups receiving 5, 10 and 15% of raw or autoclaved (120 °C for 5 min) amaranth grain based on dry matter. The results showed that the use of processed amaranth up to the level of five and ten percent of the diet compared to raw amaranth resulted in a better performance than the control group (p < 0.05). The consumption of amaranth decreased blood glucose, cholesterol and triglyceride of trial birds without having a negative effect on their health and blood antioxidant status (p < 0.05). The use of different forms of amaranth in diets of laying hens had no negative effects on the physicochemical properties of eggs and led to the production of eggs with reduced yolk cholesterol and triglyceride; however, the omega-6 content in eggs and the ratio of omega-6/omega-3 increased (p < 0.05). In conclusion, the use of amaranth grain at low levels in the diet of laying hens can enhance the health of the bird and the production of quality and useful eggs.

Effect of Dietary Amaranth (Amaranthus hybridus chlorostachys) Supplemented with Enzyme Blend on Egg Quality, Serum Biochemistry and Antioxidant Status in Laying Hens.

A feeding trial was performed to assess the effects of dietary raw amaranth (Amaranthus hybridus chlorostachys) grain (RAG), with or without an enzyme blend, on the productive performance, blood biochemistry, and antioxidant status in laying hens. The trial was conducted following a completely randomized design by factorial method, including five levels of RAG (0, 10, 20, 30, and 40%, respectively) and two levels of enzyme blend (0 -E and 0.025 +E %). A total of 960 White Leghorn (Hy-line W-36) laying hens (56 weeks of age) were divided into 10 groups with eight repetitions, including 12 birds. The trial period was ten weeks. Results showed that RAG levels in feed (>10%) led to a significant decrease in blood total cholesterol (TC), but they also significantly decreased feed conversion ratio (FCR) (p ˂ 0.05) as measured by feed intake (FI), hen daily production (HDP), egg weight (EW), and mass (EM), leading to overall worse productivity compared to the control group. On the contrary, the addition of the enzyme blend led to an improvement in the investigated production traits (p ˂ 0.05), with the exception of HDP. The enzyme blend was also capable of recovering productive performance when combined with low concentrations of RAG (10%) (p ˂ 0.05), and RAG × enzyme blend groups showed the lowest values of TC (p ˂ 0.05). Moreover, the interaction effects for atherogenic index (LDL/HDL) indicated a significant and promising reduction in response to the addition of RAG both in the presence and absence of the enzyme blend (p ˂ 0.05), and this additive also significantly reduced levels of egg yolk cholesterol (p ˂ 0.05). In summary, the evidence gathered in this trial showed that dietary RAG had positive effects on egg quality characteristics, leading to the production of low-cholesterol eggs, and, at the same time, it may improve the health status of laying hens. Furthermore, the addition of an enzyme blend allowed feeding up to 10% RAG in the diet, leading to an optimal balance between animal productivity and the beneficial effects of RAG.

Effects of Using Processed Amaranth Grain with and without Enzyme on Performance, Egg Quality, Antioxidant Status and Lipid Profile of Blood and Yolk Cholesterol in Laying Hens.

The objective of this study was to investigate the effects of feeding Amaranthus hybridus chlorostachys grain (AG) with (+E) and without enzyme (−E) on performance, egg quality, antioxidant status and lipid profile of blood serum and yolk cholesterol in laying hens. A total of 960 white leghorn (Hy-line W-36) commercial layers (56 weeks) were divided into 10 groups with 8 replicates per group (12 birds per replicate, including 3 adjacent cages with 4 birds each). A completely randomized design was implemented with a 5 × 2 factorial arrangement of treatments consisting of five levels of AG (0, 100, 200, 300 and 400 g/kg) and two levels of multienzyme complex addition (0 −E and 0.25 +E g/kg) fed to the hens for 12 weeks (2 wk. adaptation + 10 wk. main experiment). Feed intake (FI) and percentage of hen day production (HDP) were not affected by main effect of the AG level, but egg mass (EM) and egg weight (EW) were decreased (p < 0.01), and the feed conversion ratio (FCR) was impaired (p < 0.01). EM, EW and FCR were improved by enzyme addition (p < 0.01). EM, EW and FCR were affected (p < 0.01) by the interaction of AG and enzyme addition. The highest value of EM and the lowest value of FCR were observed in hens on the diet containing 200 g/kg AG with enzyme addition. Egg yolk cholesterol content was reduced (p < 0.05) by up to 10% with increasing levels AG in experimental diets. The egg quality traits, including Haugh units of protein quality, strength and shell thickness, were not affected by the main effects or interaction of AG and enzyme consumption. Amaranth feeding led to a decrease (p < 0.05) in triglyceride (TG) and low-density lipoprotein (LDL) while also promoting increases (p < 0.05) in the high-density lipoprotein (HDL) and total antioxidant capacity (TAC) of the blood. A comparison of the effects of contrasts showed that functional parameters (except FI), yolk cholesterol, antioxidant parameters (except MDA) and blood lipid profile had differed significantly (p < 0.05) between the hens fed amaranth versus those not fed amaranth. These findings indicate that feeding a diet containing up to 200 g/kg of AG with enzyme addition can improve EW, EM and FCR. Feeding laying hens diets containing AG also positively influenced blood traits and antioxidant status in laying hens while reducing egg yolk cholesterol content.

Effect of dietary flaxseed meal supplemented with dried tomato and grape pomace on performance traits and antioxidant status of laying hens.

This study was carried out to determine the effect of dietary flaxseed meal (FSM) supplemented with dried tomato pomace (DTP) and dried grape pomace (DGP) on performance, egg quality, biochemical parameters traits and antioxidant status of laying hens. Birds (1825 ± 87 g of body weight) were divided into 12 dietary groups with six replicates per group (eight birds per replicate), under a completely randomized design with factorial arrangement 2 × 3 × 2 consisted of two levels of DTP (0 and 15%), three FSM levels (0, 4 and 8%) and two levels of DGP (0 and 5%). As a result of this study, there were no significant differences in egg production and weight as well in feed conversion ratio (FCR) among treatments (p > 0.05). Feeding of DGP reduced significantly feed intake and egg mass when compared to control group (p < 0.05). There was no effect (p > 0.05) of dietary treatment on shell thickness and strength, shape index, Haugh unit and egg specific gravity. Hens consuming 15% DTP and 5% DGP revealed a significantly higher yolk color compared to the other dietary treatments (p < 0.05). Moreover, there was no difference among dietary treatments in terms of serum low-density lipoprotein cholesterol (LDL) and high-density lipoprotein cholesterol (HDL) cholesterol, atherogenic index, triglycerides, total cholesterol levels (p > 0.05). Serum antioxidant parameters as glutathione peroxidase (GSH-Px) activity, malondialdehyde (MDA), total superoxide dismutase (TSOD) and total antioxidant capacity (T-AOC) were not influenced by treatments (p > 0.05). Based on findings, FSM and DTP supplements did not significantly impact most of hens' performance indicators and egg quality parameters, whereas significant improvements were observed by feeding of 15% DTP and 5% DGP on egg traits, in particular on egg-yolk color that plays a key-role in consumer's choice. However, the supplementation of FSM and DTP or DGP even in laying hen diet is still controversial and further research is needed.

Effects of Horsetail (Equisetum arvense) and Spirulina (Spirulina platensis) Dietary Supplementation on Laying Hens Productivity and Oxidative Status.

The purpose of this study was to examine the effect of dietary horsetail (Equisetum arvense) and spirulina (Spirulina platensis) supplementation on performance, egg quality, serum biochemical and antioxidant status of laying hens. A total of 648, 63-week-old Hy-Line W-36 layers were divided into nine groups with eight replicates per group (nine birds per replicate). A feeding trial was conducted under completely randomized design with factorial arrangement 3 × 3 consisting of three different dietary levels of horsetail supplementations (0, 0.25, and 0.50%, respectively) in combination with three levels of spirulina (0, 1, and 2%, respectively). Results showed that feed intake, egg production, egg weight and mass, and feed conversion ratio were not significantly affected by the dietary treatments. Eggshell thickness, strength, and yolk color were significantly improved in diets supplemented with 0.5% horsetail and 2% spirulina and their interactions. Egg yolk cholesterol was not significantly different among groups; however, a significant reduction was found when fed 2% spirulina. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) concentration decreased by supplementing 2% spirulina in diet; also, spirulina increased total superoxide dismutase (TSOD) and total antioxidant capacity (TAC) in laying hens. Overall, the findings indicated that the combination of horsetail and spirulina could have potential for improving the egg's physical parameters, whereas spirulina was more effective in improving blood traits and oxidative status.

Effect of dietary sesame (Sesame indicum L) seed meal level supplemented with lysine and phytase on performance traits and antioxidant status of late-phase laying hens.

OBJECTIVE: This study was performed to investigate the effects of supplementing sesame seed meal (SSM) with phytase and lysine on performance, egg quality, blood biochemical and antioxidant status of laying hens. METHODS: A total of 960, 56-wk-old laying hens were divided into 12 dietary groups with eight replicates per group (10 birds per replicate). A completely randomized design with factorial arrangement 2×3×2 consisted of two levels of lysine supplement (0 and 10% over requirement), three SSM levels (0, 10 and 20%) with or without phytase (0 and 300 g/ton). The feeding trial lasted 10 weeks. RESULTS: From findings, birds fed diets with 10% SSM had higher feed intake than groups fed 0 and 20% SSM. The addition of phytase to experimental feeds, improved feed conversion ratio (FCR), increased egg weight and mass (P&lt;0.01). Egg quality criteria was not affected by supplementing phytase; however, supplementing 300 g/ton phytase to hens diet, led to a significant (P&lt;0. 05) increase in egg shell strength. Egg yolk cholesterol and serum low-density lipoprotein cholesterol (LDL-C), atherogenic index and total cholesterol were decreased (P&lt;0.01) by diet containing 20% SSM. The high-density lipoprotein cholesterol (HDL-C) was increased (P&lt;0.05) in serum of hens fed 20% SSM than the other groups. It was also observed that total antioxidant capacity (TAC) and total superoxide dismutase (TSOD) content of hens fed 20% SSM was significantly upper than control group (P&lt;0.05). CONCLUSION: As from results, dietary supplementation of SSM and phytase had no negative effects on laying hens performance or egg quality improving also the egg oxidative stability.

The impact of in ovo injection of l-arginine on hatchability, immune system and caecum microflora of broiler chickens.

The present article was conducted to evaluate the effect of in ovo injection of arginine on hatchability, immune system and caecum microflora of broiler chickens. For this reason, 300 fertile eggs were used in a completely randomized design with three experimental treatments. The experimental groups included: 1%-0.5% l-arginine (100 eggs), 2%-1% l-arginine (100 eggs), 3- control [included both sham control (injection of distilled water; 50 eggs) and control (no injection; 50 eggs)], which were injected on d 14 of incubation. After hatching, chicks of each experimental group (0.5% l-arginine, 1% l-arginine, and control groups) were randomly divided into four equal groups (as replicates) and reared for 30 days. Weight and feeding of chickens were recorded. Next, blood samples of chickens were collected on day 30 to evaluate antibody titre. Also, chickens were slaughtered on 24 and 30 days of the experiment to evaluate immune system organs and caecum microflora. Based on the results, in ovo injection of l-arginine had no significant effect on hatchability, body weight, antibody titre, spleen, bursa of Fabricius and thymus weight (p > .05). On the other hand, treatments significantly affected feed intake and feed conversion ratio (p < .05). As a novel finding, in ovo injection of l-arginine increased caecal Lactobacillus (p < .01), while decreasing Coliform and Escherichia Coli bacteria (p < .01). However, treatments did not influence caecal Enterococcus (p > .05). The overall results indicated that in ovo injection of 0.5% l-arginine had a better improving effect on caecal microflora and then considered as a recommended level of the present experiment.

Effects of Using Artemisia annua Leaves, Probiotic Blend, and Organic Acids on Performance, Egg Quality, Blood Biochemistry, and Antioxidant Status of Laying Hens.

This study was performed to investigate and compare the effects of using Artemisia annua leaves, probiotic, and organic acid on the performance, egg quality, blood biochemistry, and antioxidant status of laying hens. In total, 288 Hy-Line W-36 commercial layers (32 weeks old) were divided into six groups with six replicates per group (eight birds per replicate) and were fed one of six experimental diets. The hens were fed either a corn-soybean meal basal diet (control) or the basal diet supplemented with 2.5% A. annua leaves (AA1), 5% A. annua leaves (AA2), 7.5% A. annua leaves (AA3), 0.1% probiotic (Pro), and 0.005% organic acid (Org), respectively. The experiment lasted 10 weeks. Results showed that there were differences in the feed conversion ratio (FCR) among experimental groups (P<0.05). The highest yolk color index and shell thickness were observed in hens fed AA3 and AA2 diets (P<0.05). Egg yolk cholesterol was decreased (P<0.01) by the diet containing AA3 and Pro compared to the other groups. The atherogenic index was lower (P<0.01) in the plasma of hens fed AA3 than those in other groups. The glutathione peroxidase activity (GSH-Px) and malondialdehyde (MDA) contents in layers fed AA3 were lower and higher (P<0.05), respectively, than in layers fed the other diets. Moreover, the concentration of plasma cholesterol was decreased (P<0.05) in layers fed AA3 and Pro. In conclusion, feeding laying hens with A. annua leaves positively influenced the plasma antioxidant status, and the dietary inclusion of A. annua leaves plus a probiotic significantly decreased the egg yolk cholesterol, with no adverse effect on the egg productive traits.