Effects of sunflower meal supplementation in the diet on productive performance, egg quality and gastrointestinal tract traits of laying hens

Interaction between energy level and starch:fat ratio on intestinal energy metabolism of layer pullets

During the growing period, the gastrointestinal tract of layer pullets is not yet well developed and may be susceptible to dietary energy level. The energy level and composition might impact the intestinal energy metabolism of layer pullets. To test this hypothesis, a total of 480 "Jing Tint 6" layer pullets were used in an 8-week study and allocated to 4 groups, each consisting of 8 replicates, with 15 birds per replicate. Pullets were treated with low or high starch:fat ratios (LS, 10:1; HS, 20:1) in a 2 × 2 factorial arrangement with regular energy (RE, 11.85 and 11.68 MJ/kg for birds from 6 to 10 weeks of age and 11-14 weeks of age, respectively) or low energy (LE, 0.55 MJ/kg lower than RE) levels. A significant interaction (P < 0.05) showed that HS increased glandular stomach weight and the jejunal villus length to crypt depth ratio (VCR) in LE diets, but decreased these parameters in RE diets. Dietary energy reduction impaired energy metabolism in the ileum (P < 0.05) mainly via decreasing the gene expression of enzymes involved in the tricarboxylic acid (TCA) cycle (α-ketoglutarate dehydrogenase complex [α-KGDH]; isocitrate dehydrogenase (NAD (+) [IDH] catalytic; citrate synthase [CS]) and adenosine triphosphate (ATP) synthesis, reducing contents of phosphoenolpyruvate (PEP) and adenylate energy charges (AEC) and down-regulating the adenosine monophosphate-activated protein kinase (AMPK) pathway. HS stimulated AMPKα phosphorylation, increased protein abundance of peroxisome proliferator activated-receptor gamma coactivator 1α (PGC1α) and improved contents of amino acids (aspartate, glutamate, glutamine, alanine and threonine) and malate in the ileum regardless of energy levels (P < 0.05). By an interaction (P < 0.05), the transition from LS to HS diets up-regulated ileal gene expression of AMPKα1 and decreased content of adenosine monophosphate (AMP), accompanied by higher AEC but only in birds fed with LE diets. Collectively, these results suggest that low energy feeding may not be enough for maintaining intestinal energy homeostasis in layer pullets and emphasizes the importance of a relatively high starch:fat ratio in restoring energy metabolism in the ileum.

Dietary Fiber-Rich Spartina anglica Improves Intestinal Health and Antioxidant Capacity of Zhedong White Geese

Spartina anglica (SA), a plant rich in dietary fiber, has demonstrated considerable potential for enhancing gut health and antioxidant capacity in animals. This study investigates the integration of SA as a novel dietary ingredient for Zhedong white geese, with a specific focus on evaluating its effects on growth performance, nutrient digestibility, antioxidant capacity, intestinal health, and cecal microbiota composition. A total of 360 1-day-old Zhedong white geese with an average weight of 114.94 ± 0.81 g were randomly allocated to 4 dietary treatments, with 6 replicates per treatment and 15 geese per pen. The 4 dietary treatments included different SA supplement levels: a control group receiving a basal diet (CON), and three experimental groups supplemented with 3% SA (SA3), 6% SA (SA6), and 12% SA (SA12). Supplementation with 6% SA significantly enhanced the final body weight, average daily gain, and feed conversion ratio (FCR) compared to the CON group (p < 0.05). In contrast, the SA12 group exhibited reduced digestibility of crude protein and ether extract, relative to the SA3 and SA6 groups (p < 0.05). The highest antioxidant capacity was observed in the SA6 and SA12 groups, while the lowest was recorded in the CON group. SA supplementation did not significantly influence serum biochemical parameters or organ indices but increased cecum length (p < 0.05). Notably, SA supplementation markedly improved intestinal morphology, although excessive levels appeared to compromise these benefits. Additionally, SA supplementation significantly enhanced the richness and diversity of cecal microbiota and increased short-chain fatty acid concentrations. In conclusion, SA at an optimal supplementation level of 6% may be effectively utilized in Zhedong white geese diets to improve growth performance, gut health, and antioxidant capacity.

Determination and prediction of the apparent and standardized ileal amino acid digestibility in soybean meal fed to the pullets

This experiment was conducted to evaluate the chemical composition, apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of amino acid (AA) in 10 different sources of soybean meal (SBM) fed to the pullets and established prediction equations based on the chemical composition of SBM. 792 Hy Line Brown hens aged 12-15 weeks were divided into 11 diet groups, the diets included one nitrogen-free diet (NFD) used to measure the basal endogenous losses of AA and 10 SBM test diets containing 35.2 % SBM as the sole source of AA. The 0.5 % titanium dioxide (TiO2) was used as an indigestible marker. The results shown that there was considerable variation in crude ash (Ash), ether extract (EE), and acid detergent fiber (ADF) content in the 10 SBM samples with a coefficient of variation greater than 10 %. The AID and SID of both indispensable and dispensable AA except for the Cys and Ala among the 10 SBM differed (P < 0.05). The AID of AA was correlated with the dry matter (DM), gross energy (GE), crude protein (CP), EE, Ash, and reactive Lys (rLys) (P < 0.05), and SID of AA was correlated with the GE, CP, EE, CF, neutral detergent fiber (NDF) and rLys (P < 0.05). With R2 values exceeding 0.39, significant linear regression equations for the AID of Met, Phe, Lys, Asp, and Gly, as well as SID of Met, Phe, Lys, Ser and Tyr were obtained. The best fit equation for the AID of Asp was the DM, GE, Ash and rLys (R2 = 0.820, P = 0.042), and the SID of Lys was the GE, CP, CF, Ash, ADF and rLys (R2 = 0.989, P = 0.005), respectively. In conclusion, this experiment suggested that the rLys can be used to predict the AID and SID of AA in SBM with reasonable accuracy together with the basal chemical composition, and prediction equations for AID and SID could be used to evaluate the digestibility of SBM in the pullets.

The Influence of Dietary Supplementation with Dried Olive Pulp on Gut Microbiota, Production Performance, Egg Quality Traits, and Health of Laying Hens

This study examines the dietary effect of dried olive pulp (OP) on the overall performance, egg quality, health, and gut microbiota of laying hens during a 36-week trial. A total of 180 Isa Brown layers, aged 23 weeks, were assigned to 15-floor pens and divided into three feeding groups (CON, OP4, and OP6) based on the dietary level of OP. Egg quality and biochemical parameters were assessed in 39- and 59-week-old hens. Fecal samples were collected for microbiota analysis. Data were analyzed with an Analysis of Variance. The percentage of broken eggshells was found to be 15-34% lower in the OP groups compared to the CON groups. At 59 weeks of age, a significant reduction in shell thickness was observed in the CON eggs compared to the OP eggs (p < 0.05). At 39 weeks of age, OP6 eggs had the darkest yolk color of all groups (p < 0.05). Fecal microbial diversity was affected only by hens' age. However, an enrichment in bacterial species belonging to the genera Megasphaera and Megamonas was found in the OP groups at 59 weeks of age. Our results demonstrate that OP feeding beneficially affects egg quality and promotes the proliferation of bacteria involved in the degradation of complex plant compounds, potentially contributing to the overall health of the gut microbiota.

Feeding sunflower meal with pullets and laying hens even at a 30% inclusion rate does not impair the ileal digestibility of most amino acids

The use of locally available protein sources in poultry nutrition is challenging for feed manufacturers and farmers. Sunflower meal (SFM) is available in high quantities in several European countries and could be used as a poultry feedstuff at higher inclusion rates. However, its maximum inclusion rate in the diets of different poultry species and age categories is unknown. Pullets and laying hens can probably tolerate higher amounts of SFM, but only limited information is available on these poultry groups. Therefore, a digestibility trial was carried out with 8-week-old layer type pullets and 50-week-old laying hens. Beside a basal diet, SFM was fed at 10, 20 and 30% inclusion rates. Feeding SFM significantly improved the digestibility of essential amino acids (AA) of threonine, valine, lysine, tyrosine, glycine, aspartic acid, and arginine in the pullet diets. No such improvement was found in laying hens. Only the absorption of the two branch-chain AAs, leucin (pullets) and isoleucine (hens), declined due to SFM. The AA digestibility of the SFM itself was also calculated by linear regression. The coefficients were, in all cases, higher in hens than in pullets. Comparing the measured digestibility coefficients of SFM with table values, it can be concluded that high variance exists because of the differences in the methodology and the test animals in the digestibility trials. From the present trial, it can be concluded that SFM can entirely replace extracted soybean meal in pullet and layer diets, without negative effects on the protein digestion of birds.

Sunflower cake associated with crude glycerin in white laying hens diets: Performance and quality, antioxidant activity and lipid oxidation of eggs

The objective of this study was to evaluate the effects of sunflower cake inclusion and its association with crude glycerin in the diet of laying hens. A total of 320 laying hens with 39 weeks of age were distributed in a completely randomized design in a 4 × 2 factorial scheme with 5 replications of 8 birds. The studied factors were 4 inclusion levels of sunflower cake and 2 levels of crude glycerin. The inclusion of 210 g/kg of sunflower cake reduced egg mass and worsened feed conversion, and after the level 70 g/kg there was reduction in yolk coloration and specific density of eggs with or without the addition of glycerin in the diet. The addition of 70 g/kg of crude glycerin reduced the specific density of eggs in all levels of sunflower cake. There was increase in phenolic compounds, antioxidant capacity and antioxidant activity in eggs and reduction in lipid oxidation of yolks from fresh and stored eggs, with the inclusion of sunflower cake. The addition of crude glycerin increased the lipid oxidation of egg yolks. Therefore, it is possible to include up to 140 g/kg sunflower cake in the diet of laying hens, with or without crude glycerin, without impairing performance and egg quality, obtaining higher antioxidant capacity of eggs and lower lipid oxidation in yolks from fresh and stored eggs. The inclusion of 70 g/kg crude glycerin does not affect laying hens performance, however, it worsens shell quality and increases lipid oxidation in the liver and egg yolks.

Sunflower and rapeseed meal as alternative feed materials to soybean meal for sustainable egg production, using aged laying hens

1. This study assessed the impact of replacing two thirds of a soybean meal (SBM) based diet with an alternative protein (AP) based diet (sunflower and rapeseed meal), when fed to end of production Hy-Line Brown laying hens.2. Diets were fed in seven cages, each containing six birds aged from 75 to 83 weeks old. Measured variables included bird performance, egg production, quality variables of fresh eggs, total tract digestibility of dry matter (DMD), neutral detergent fibre (NDFD), fat (FD), and nitrogen corrected apparent metabolisable energy (AMEn).3. No significant differences were observed (P > 0.05) for egg production, egg composition or egg quality. However, birds fed the AP diet had darker yolks (P < 0.05), possibly linked to natural pigments in AP.4. The SBM diet had higher AMEn, DMD and NDFD (P < 0.05), although FD was higher in the AP diet (P < 0.05).5. Diets based on AP sources can be fed to aged laying hens without deteriorating productive performance, providing care is taken in formulating diets (e.g. amino acid levels, balance etc). Using AP sources may reduce reliance on SBM associated with land use change, contributing towards sustainability for the egg industry.

Natural Products of Plants and Animal Origin Improve Albumen Quality of Chicken Eggs

Albumen quality is recognized as one of the major yardsticks in measuring egg quality. The elasticity of thick albumen, a strong bond in the ovomucin-lysozyme complex, and excellent biological properties are indicators of high-quality albumen. The albumen quality prior to egg storage contribute to enhance egg’s shelf life and economic value. Evidence suggests that albumen quality can deteriorate due to changes in albumen structure, such as the degradation of β-ovomucin subunit and O-glyosidic bonds, the collapse of the ovomucin-lysozyme complex, and a decrease in albumen protein-protein interaction. Using organic minerals, natural plants and animal products with antioxidant and antimicrobial properties, high biological value, no residue effect and toxicity risk could improve albumen quality. These natural products (e.g., tea polyphenols, marigold extract, magnolol, essential oils, Upro (small peptide), yeast cell wall, Bacillus species, a purified amino acid from animal blood, and pumpkin seed meal) are bio-fortified into eggs, thus enhancing the biological and technological function of the albumen. Multiple strategies to meeting laying hens’ metabolic requirements and improvement in albumen quality are described in this review, including the use of amino acids, vitamins, minerals, essential oils, prebiotics, probiotics, organic trace elements, and phytogenic as feed additives. From this analysis, natural products can improve animal health and consequently albumen quality. Future research should focus on effects of these natural products in extending shelf life of the albumen during storage and at different storage conditions. Research in that direction may provide insight into albumen quality and its biological value in fresh and stored eggs.

Dietary fiber in poultry nutrition and their effects on nutrient utilization, performance, gut health, and on the environment: a review

Dietary fiber (DF) was considered an antinutritional factor due to its adverse effects on feed intake and nutrient digestibility. However, with increasing evidence, scientists have found that DF has enormous impacts on the gastrointestinal tract (GIT) development, digestive physiology, including nutrient digestion, fermentation, and absorption processes of poultry. It may help maintain the small and large intestine's integrity by strengthening mucosal structure and functions and increasing the population and diversity of commensal bacteria in the GIT. Increasing DF content benefits digestive physiology by stimulating GIT development and enzyme production. And the inclusion of fiber at a moderate level in diets also alters poultry growth performance. It improves gut health by modulating beneficial microbiota in the large intestine and enhancing immune functions. However, determining the source, type, form, and level of DF inclusion is of utmost importance to achieve the above-noted benefits. This paper critically reviews the available information on dietary fibers used in poultry and their effects on nutrient utilization, GIT development, gut health, and poultry performance. Understanding these functions will help develop nutrition programs using proper DF at an appropriate inclusion level that will ultimately lead to enhanced DF utilization, overall health, and improved poultry growth performance. Thus, this review will help researchers and industry identify the sources, type, form, and amount of DF to be used in poultry nutrition for healthy, cost-effective, and eco-friendly poultry production.

Effects of Sunflower Meal Supplementation as a Complementary Protein Source in the Laying Hen’s Diet on Productive Performance, Egg Quality, and Nutrient Digestibility

The practical usage of untraditional feedstuffs such as sunflower meal (SFM) in laying hens nutrition in developing countries has received considerable attention. SFM is a by-product of the sunflower oil industry and has been progressively added to bird’s diets. Sunflower meal (SFM) is gaining great interest as a feed ingredient due to its eminent crude protein content, low anti-nutritional compounds, and low price. The current experiment was aimed to assess the production efficiency, egg quality, yolk fatty acids composition, and nutrient digestibility of laying hens fed SFM. A total of 162 Bovans Brown laying hens aged 60 weeks old were randomly allocated using a completely randomized design into three experimental groups of nine replicates each (n = six/replicate) for eight weeks. The dietary treatments involved a control (basal diet) and two levels of SFM, 50 and 100 g/kg feed. The dietary treatments did not influence live weight gain, feed intake, and egg mass. On one hand, the laying rate was increased; on the other hand, the feed conversion ratio and broken eggs rate of laying hens were decreased (p < 0.05) by the dietary inclusion of SFM. Dietary treatments had no effect on the egg’s quality characteristics except the yolk color and yolk height were larger (p = 0.01) for laying hens fed SFM compared with those fed the control. Dietary inclusion of SFM decreased (p < 0.05) the content of cholesterol in the egg yolk. Still, it increased the yolk contents of vitamin E, calcium, linoleic acid, linolenic acid, and oleic acid (p < 0.05). Furthermore, the dietary inclusion of SFM increased crude protein and calcium digestibility, but decreased the ether extract digestibility. In conclusion, our results suggested that the dietary inclusion of SFM, up to 100 g/kg at a late phase of laying, could improve the production performance, some of the egg quality traits, and nutrient digestibility while decreasing egg yolk cholesterol.