Effects of Phytase Supplementation to Diets with or without Zinc Addition on Growth Performance and Zinc Utilization of White Pekin Ducks

Effect of Zinc Oxide Nanoparticles as Feed Additive on Blood Indices, Physiological, Immunological Responses, and Histological Changes in Broiler Chicks

A feeding trial of 5-week duration was performed to assess the response of broiler chicks to dietary supplementation with different doses of myco-fabricated zinc oxide nanoparticles (ZONPs) on blood indices, physiological, immunological response, antioxidant status, intestinal microbial count, and histological changes in immune organs. A total of 162 3-day-old Ross 308 broiler chicks were weighed individually and distributed equally into 3 dietary treatments with 6 replicate of 9 chicks in each in a completely randomized design. Chicks were fed ad libitum a basal ration prepared as starter, grower, and finisher supplemented with 0 (T1, control), 40 (T2), and 60 (T3) mg zinc oxide nanoparticles (ZONPs)/kg feed. Results showed that supplementing with ZONPs at both studied levels increased the relative weights of the spleen, bursa, thymus, and liver and decreased the relative weight of the kidney, gizzard, and intestine. A significant increase in the concentrations of hemoglobin (Hb), hematocrit (PCV%), red and white blood cell counts, total protein (TP), globulin (GLOB), aspartate transferase (AST), alanine transferase (ALT), alkaline phosphatase (ALP), superoxide dismutase (SOD), glutathione peroxidase (GPx), and total antioxidant capacity (TAC) and a significant decrease in malonaldehyde (MDA), uric acid, and creatinine concentration were observed. Furthermore, all immunological organs showed histological alteration and increased both types of immunity in ZONPs groups with more pronounced effects in the T2 group.

CO2-based production of phytase from highly stable expression plasmids in Cupriavidus necator H16

BACKGROUND

Existing plasmid systems offer a fundamental foundation for gene expression in Cupriavidus necator; however, their applicability is constrained by the limitations of conjugation. Low segregational stabilities and plasmid copy numbers, particularly in the absence of selection pressure, pose challenges. Phytases, recognized for their widespread application as supplements in animal feed to enhance phosphate availability, present an intriguing prospect for heterologous production in C. necator. The establishment of stable, high-copy number plasmid that can be electroporated would support the utilization of C. necator for the production of single-cell protein from CO2.

RESULTS

In this study, we introduce a novel class of expression plasmids specifically designed for electroporation. These plasmids contain partitioning systems to boost segregation stability, eliminating the need for selection pressure. As a proof of concept, we successfully produced Escherichia coli derived AppA phytase in C. necator H16 PHB- 4 using these improved plasmids. Expression was directed by seven distinct promoters, encompassing the constitutive j5 promoter, hydrogenase promoters, and those governing the Calvin-Benson-Bassham cycle. The phytase activities observed in recombinant C. necator H16 strains ranged from 2 to 50 U/mg of total protein, contingent upon the choice of promoter and the mode of cell cultivation - heterotrophic or autotrophic. Further, an upscaling experiment conducted in a 1 l fed-batch gas fermentation system resulted in the attainment of the theoretical biomass. Phytase activity reached levels of up to 22 U/ml.

CONCLUSION

The new expression system presented in this study offers a highly efficient platform for protein production and a wide array of synthetic biology applications. It incorporates robust promoters that exhibit either constitutive activity or can be selectively activated when cells transition from heterotrophic to autotrophic growth. This versatility makes it a powerful tool for tailored gene expression. Moreover, the potential to generate active phytases within C. necator H16 holds promising implications for the valorization of CO2 in the feed industry.

Interactions of zinc with phytate and phytase in the digestive tract of poultry and pigs: a review

Phytase supplementation is gaining importance in animal nutrition because of its effect on phosphorus (P) digestibility and the increasing relevance of P for sustainable production. The potential inhibitors of phytase efficacy and phytate degradation, such as calcium (Ca) and zinc (Zn), have been a subject of intense research. This review focuses on the interactions of Zn with phytate and phytase in the digestive tract of poultry and pigs, with an emphasis on the effects of Zn supplementation on phytase efficacy and P digestibility. In vitro studies have shown the inhibitory effect of Zn on phytase efficacy. However, relevant in vivo studies are scarce and do not show consistent results for poultry and pigs. The results could be influenced by different factors, such as diet composition, amount of Zn supplement, mineral concentrations, and phytase supplementation, which limit the comparability of studies. The chosen response criteria to measure phytase efficacy, which is mainly tibia ash, could also influence the results. Compared to poultry, the literature findings are somewhat more conclusive in pigs, where pharmacological Zn doses (≥ 1000 mg kg-1 Zn) appear to reduce P digestibility. To appropriately evaluate the effects of non-pharmacological Zn doses, further studies are needed that provide comprehensive information on their experimental setup and include measurements of gastrointestinal phytate degradation to better understand the mechanisms associated with Zn and phytase supplements. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Approaches to determine the efficiency of novel 3-phytase from Klebsiella pneumoniae and commercial phytase in broilers from 1 to 14 d of age

This study aimed to evaluate the effects of a laboratory 3-phytase (the expression of the phyK gene, Lab-Phy) and a commercial 6-phytase (Quantum Blue 40 P, Com-Phy) alone and in combination (corn-soy-based diets) in broilers. A total of 400, day-old Ross 308 male broilers were randomly assigned to 5 treatments with 10 replicate cages (8 chicks/cage) for a 14-day trial. Experimental treatments included the positive control (0.95% Ca and 0.48% nonphytate phosphorus (nPP), PC), negative control (0.90% Ca and 0.22% nPP, NC), and NC which was supplemented with Lab-Phy 250 FTU/kg and Com-Phy 250 FTU/kg alone or in combination of Lab-Phy 125 FTU/kg and Com-Phy 125 FTU/kg. The inclusion of Lab-Phy in the NC diet significantly improved the P and Ca content in the tibia compared to the NC group. Moreover, the inclusion of Com-Phy alone and in combination with Lab-Phy in the NC diet significantly increased the P and Ca content in the tibia compared to the Lab-Phy. The mRNA expression of NaPi-IIb was upregulated in the duodenum by the reduction of nPP and downregulated by the inclusion of any phytase, whereas other nutrient transporters were not influenced by the reduction of nPP or the addition of phytase in the small intestine mucosa. Broilers receiving the NC diet obtained the lowest body weight (BW) and body weight gain (BWG) at 8 to 14 and 1 to 14 d of age. The NC group showed the lowest villi height and surface area, Newcastle disease (ND) antibody titer, and digestibility of nutrients compared to the PC group at 14 d of age. Supplementing the NC diet with the Lab-Phy and Com-Phy individually, or in combination tended to improve BW, BWG, tibia characteristics, villi characteristics, ND, and retained CP and P, and apparent ileal digestibility of CP, P, methionine, and threonine. The present research indicated that the studied traits by the combination of phytases were slightly better than the average of the 2 individually, suggesting there might be some value in combining the laboratory and commercial phytases.

Health risk assessment of metals in chicken meat and liver in Egypt

This study aimed to evaluate the concentration of metals such as aluminum (Al), cadmium (Cd), lead (Pb), barium (Ba), bismuth (Bi), cobalt (Co), nickel (Ni), chromium (Cr), iron (Fe), copper (Cu), zinc (Zn), and selenium (Se) in 360 samples of poultry meat and liver from six brands (A, B, C, D, E, and F) in Assiut, Egypt; compare these concentrations with Egyptian and world permissible limits; and determine their safety for human consumption according to health risk assessment. Chest, thigh muscles, and liver were collected randomly from Assiut city markets, and the concentration of heavy metals was measured in the central laboratory of the faculty of agriculture at Assiut University using inductively coupled plasma mass spectrometry (ICP-MS). All the analyzed samples were positive for the tested metals and were far below the allowed maximum permissible limits except for Pb and Fe, which exceeded the Egyptian Organization for Standardization (EOS) permissible limits with 33% and 67%, respectively, as well as Pb and Cd, which exceeded FAO/WHO permissible limits with 94% and 17%, respectively. Health risk assessment revealed the safety and minimum health risk for human consumption of metal residues in poultry tissues and liver using estimated daily intake (EDI), target hazard quotient (THQ), hazard index (HI), and target cancer risk (TR). Even though the THQ and HI values were significantly lower than 1.0 during our study, heavy metal monitoring in poultry products and byproducts is required for human security and safety.

Evaluation of an Innovative Zn Source on Feed Efficiency, Growth Performance, Skin and Bone Quality of Broilers Suffering Heat Stress

One thousand two hundred male broilers were used to evaluate the effect of different dosages of HiZox® on feed efficiency, growth performance and bone quality of broilers suffering from heat stress. A completely randomized design was used, with four treatments and ten replicates. Basal corn−soybean meal diets supplemented with 75, 100 and 125 mg/kg zinc from HiZox and 100 mg/kg zinc from regular ZnO were used to make four treatments. Heat stress was induced after the third week by keeping house temperature between 28−34 °C, from 1 pm until 5 pm. The body weights of the birds that received the diet supplemented with HiZox or ZnO showed no significant difference at 7 and 14 days. Body weight of heat stressed birds fed diets containing different levels of HiZox or ZnO were not different at 28 and 42 days of age. In comparison to the Ross 308 management guide, induced heat stress diminished body weight and feed intake by approximately 17 and 21%, respectively. At 28 days, chickens who received 125 mg/kg Zn from Hizox had better feed efficiency (p < 0.05). The mortality rate of heat-stressed male broiler chickens who received different dosages of HiZox was 2.85% less than that of the regular ZnO group (p < 0.06). The results showed that addition of HiZox to the diet of male broiler under heat stress doubled the skin resistance during feather plucking in the slaughter plant and improved carcass quality (p < 0.07). Tibia breaking strength, included elongation and extension were improved by consumption of a diet supplemented with 75 mg HiZox/kg (p < 0.09). The HiZox-75 fed broilers required higher amounts of energy (MJ) for tibia breaking at break and peak points at 42 days (p < 0.09; p < 0.07). Jejunum Zn concentrations reflected the quantity of ingested Zn (p < 0.0001). Gizzard Zn solubility was dependent on dietary treatment (p < 0.03). Solubility of Zn in the gizzard of chickens who received HiZox was higher (about 30%) than broilers fed regular ZnO. In conclusion, Zn from HiZox was more efficient in decreasing heat stress mortality, increasing skin resistance and bone breaking strength compared to a regular ZnO source.

The impact of multi-enzyme fortification on growth performance, intestinal morphology, nutrient digestibility, and meat quality of broiler chickens fed a standard or low-density diet

This research aimed to study the impact of supplementation of three multi-enzyme levels (0, 0.1, and 0.2% of feed) and two levels of dietary treatments [standard diet (SD) and low-density diet (LDD)] on growth performance, carcass traits, digestibility, and meat quality of broilers from 1 to 38 days of age. A total of 216 1-day-old Arbor Acres broiler chicks were randomly assigned to a factorial experiment (2 × 3) comprising six dietary treatments, each with six replicates and each replicate with six chickens. The results showed that the LDD significantly reduced body weight gain by 5.0%, compared with the SD. Multi-enzymes significantly improved body weight gain and the production index (PI) relative to the SD. The feed conversion ratio was significantly enhanced with increased multi-enzymes from 1 to 21 days. A significant relation between the multi-enzyme concentration and type of dietary treatment was observed in body weight gain and feed conversion ratio from 1 to 21 days of age. Nitrogen-free extract digestibility was significantly increased by using the SD diet compared with using the LDD. Multi-enzyme supplementation improved the digestibility of dry matter, crude protein, crude fiber, and nitrogen-free extract in the LDD. A significant relationship was found between the multi-enzyme concentration and type of dietary treatment on the pancreas, liver, and intestinal length percentages. The meat dry matter concentration was significantly higher in the LDD group than in the SD group. The low-density diet significantly reduced the total revenue compared with the SD, whereas broilers fed the SD recorded significantly higher total revenue and economic efficiency than those fed the LDD. The low-density diet significantly increased economic efficiency compared with the SD. Multi-enzymes significantly increased the total revenue, net revenue, and economic efficiency than the standard set. In conclusion, using multi-enzymes in broiler diets improved body weight gain. The LDD with multi-enzymes showed enhanced body weight gain compared with the SD without multi-enzymes.

Phytase Supplementation of Four Non-Conventional Ingredients Instead of Corn Enhances Phosphorus Utilization in Yellow-Feathered Broilers

The present study was conducted to evaluate the effects of unconventional feedstuff such as wheat, broken rice, distillers dried grains with soluble (DDGS), and wheat bran, replacing 15% of the corn in the basal diet and the supplementation of bacterial phytase on nutrition digestibility. A total of 500 yellow-feathered broilers with similar body weights of 1.65 ± 0.15 kg were divided into 10 dietary treatments with 5 replicates per treatment (5 male and 5 females per cage). The AME and AIDE were significantly higher when supplied with phytase (p < 0.01) in the DDGS group. The ileal and total tract digestibility of calcium and phosphorus were significantly increased in the phytase-supplied group (p < 0.001). Additionally, the ileal digestibility of CP was increased when phytase was supplemented (p < 0.001). The results infer that the wheat, broken rice, DDGS, and wheat bran had no negative effect when replacing 15% corn. Supplementing 0.02% phytase in their diets can effectively optimize nutrient digestibility in yellow broilers.

A perspective review on the effect of different forms of zinc on poultry production of poultry with special reference to the hazardous effects of misuse

Zinc (Zn) is a unique micro-mineral because it is an essential component in many enzymes such as superoxide dismutase, carbonic anhydrase, and alkaline phosphatase, as well as being important for regulation of proteins and lipids metabolism, and sex hormones. This mineral is applied in poultry production in three forms; inorganic, organic, and nanoparticle form. The nano-form of Zn is preferable in application to other conventional forms with regard to absorption, bioavailability, and efficacy. Broilers fed on diets supplemented with Zn showed improvement of growth performance, carcass meat yield, and meat quality. In addition, Zn plays an important role in enhancing of both cellular and humeral immune responses, beside its antimicrobial and antioxidant activities. In laying hens, dietary addition of Zn improves the eggshell quality and the quantity of eggs. Moreover, Zn has a vital role in breeders in terms of improving the egg production, fertility, hatchability, embryonic development, and availability of the hatched chicks. Therefore, this review article is focused on the effects of using Zn on the performance and immunity of poultry, as well as its antimicrobial and antioxidant properties with special reference to the hazardous effects of the misusing of this mineral.

Effect of Supplemental Zinc on Performance, Nutrient Digestibility, Jejunum Architecture, and Immune Response in Broiler chickens Fed Wheat-Soy Diets

The present study was conducted to evaluate the effect of dietary zinc (Zn) levels on growth performance, carcass characteristic, nutrient digestibility, jejunum architecture and immune responses in broiler chickens fed wheat-soy diets. In addition the Zn requirement to optimize responses were estimated through regression models. A total, of 250 day-old male Ross-308 broiler chicks were randomly allocated to a completely randomized design experiment with five dietary treatments of five replicates of 10 birds each. Birds were fed diets containing 30, 70, 110, 150, and 190 mg/kg Zn from 1 to 35 days of age. A Zn level of 70 mg/kg diet was adequate to acquire typical growth performance, the nutrient digestibility, and carcass yield. First antibody titres response to sheep red blood cell inoculation, cutaneous basophil hypersensitivity elicited by phytohemagglutinin-P intradermal injection increased linearly by the increase in dietary Zn level. The Zn requirement estimated by the quadratic and linear broken-line models was varied between 63-70 mg/kg to optimize growth performance criteria. It is concluded the basal Zn concentration in wheat-soy diet is inadequate to fulfill the broiler chickens genetic potential in growth and a minimum of 70 mg/kg dietary Zn concentration is suggested to optimize broiler chickens performance.

Age features and reference intervals for the concentrations of some essential and toxic elements in laying hens

Background and Aim: Micronutrient imbalances pose a severe threat to the health and productivity of livestock and poultry. In this regard, a further stage in feeding science development will control and optimize the intake of mineral substances, including determining the elemental composition in some biosubstrates. One of these biosubstrates can be a feather. However, the amount of available information on the content of trace elements in laying hens is limited, complicating the laboratory data interpretation. Therefore, this study established reference intervals for the concentrations of the main essential and toxic elements in laying hens in different periods of ontogenesis. Materials and Methods: The study was conducted on clinically healthy Hisex Brown laying hens at the age of 10 (n=150), 30 (n=150), 120 (n=150), 150 (n=150), and 210 (n=150) days. All examined birds were born and raised on the territory of the South Ural biogeochemical province of Russia. The sampling of feathers was carried out by plucking the flight feathers of the wing. Inductively coupled plasma dynamic reaction cell mass spectrometry determined the elemental composition of the feather according to 25 parameters. Results: The results showed that at the minimum age (10 days), the highest concentrations of chemical elements were observed in laying hens. Subsequently, as they grew older, in the period from the 30th to the 120th day, there was a significant decrease in these indicators. Later, from the 120th to the 150th day, a statistically significant increase in concentrations was replaced. Little growth and relative concentration stability were observed in the last part of the experiment (150-210 days). Chemical element concentrations in feathers were computed in reference ranges for each age group. Conclusion: The calculated ranges of chemical element concentrations in laying hens can be used to compile norms for their content in the body; however, it is worth noting that these ranges can vary depending on the biogeochemical province of breeding and the bird's age.

Supplementation of different zinc sources to low-CP diets and its effect on performance, carcass traits, liver and kidney functions, immunological, and antioxidant parameters of quail chicks

The present study was performed to evaluate the influence of low crude protein (CP) levels, zinc sources (organic as zinc methionine-Zn-Met and inorganic as zinc oxide-ZnO) and their interactions on growth performance, carcass traits, and blood components of growing Japanese quail. A total of 450 one-wk-old Japanese quail with the same body weights were randomly distributed into 9 groups of 50 birds. The 9-diet treatments comprised 3 levels of CP (20, 22, and 24%) and 3 Zn source (0 g of Zn/kg diet, 0.1 g ZnO/kg diet, and 0.1 g Zn-Met/kg diet). The results obtained from this study showed that there were no significant differences among the groups, except for differences in body weight (BW) and body weight gain (BWG) at 3 to 5 – and 1 to 5 wk of age for quail supplemented with 24% and 20% CP. All the studied biochemical parameters were significantly influenced by different levels of CP and Zn, except urea and creatinine, which were affected by CP levels only. In conclusion, dietary protein level for growing Japanese quails could be reduced to 20% without negative effects on their performance, carcass traits, and blood metabolites.

Nanominerals: Fabrication Methods, Benefits and Hazards, and Their Applications in Ruminants with Special Reference to Selenium and Zinc Nanoparticles

Simple Summary

Nanomaterials can contribute to the sustainability of the livestock sector through improving the quantitative and qualitative production of safe, healthy, and functional animal products. Given the diverse nanotechnology applications in the animal nutrition field, the administration of nanominerals can substantially enhance the bioavailability of respective minerals by increasing cellular uptake and avoiding mineral antagonism. Nanominerals are also helpful for improving reproductive performance and assisted reproductive technologies outcomes of animals. Despite the promising positive effects of nanominerals on animal performance (growth, feed utilization, nutrient bioavailability, antioxidant status, and immune response), there are various challenges related to nanominerals, including their metabolism and fate in the animal’s body. Thus, the economic, legal, and ethical implications of nanomaterials must also be considered by the authority.

Abstract

Nanotechnology is one of the major advanced technologies applied in different fields, including agriculture, livestock, medicine, and food sectors. Nanomaterials can help maintain the sustainability of the livestock sector through improving quantitative and qualitative production of safe, healthy, and functional animal products. Given the diverse nanotechnology applications in the animal nutrition field, the use of nanomaterials opens the horizon of opportunities for enhancing feed utilization and efficiency in animal production. Nanotechnology facilitates the development of nano vehicles for nutrients (including trace minerals), allowing efficient delivery to improve digestion and absorption for better nutrient metabolism and physiology. Nanominerals are interesting alternatives for inorganic and organic minerals for animals that can substantially enhance the bioavailability and reduce pollution. Nanominerals promote antioxidant activity, and improve growth performance, reproductive performance, immune response, intestinal health, and the nutritional value of animal products. Nanominerals are also helpful for improving assisted reproductive technologies (ART) outcomes by enriching media for cryopreservation of spermatozoa, oocytes, and embryos with antioxidant nanominerals. Despite the promising positive effects of nanominerals on animal performance and health, there are various challenges related to nanominerals, including their metabolism and fate in the animal’s body. Thus, the economic, legal, and ethical implications of nanomaterials must also be considered by the authority. This review highlights the benefits of including nanominerals (particularly nano-selenium and nano-zinc) in animal diets and/or cryopreservation media, focusing on modes of action, physiological effects, and the potential toxicity of their impact on human health.

High levels of copper and zinc supplementation in broiler diets on growth performance, carcase traits and apparent ileal mineral absorption

1. This study investigated the effects of hydroxy trace minerals (HTM) compared to sulphate trace minerals (STM) supplementation on growth performance, carcase parameters and mineral retention in broilers.2. A total of 1792 male Cobb 500 d-old were allocated in a completely randomised trial design to one of eight dietary treatments with eight replicates per treatment. The HTM sources used were two levels of Cu hydroxychloride (CHC) (low and high), combined with three levels of Zn hydroxychloride (ZHC) (low, med and high) and two additional treatments STM; Cu sulphate monohydrate (CSM) (low and high) combined with high Zn sulphate monohydrate (ZSM). At 21 and 42 d-old growth performance was evaluated. Additionally, at 42 d-old the carcase traits, meat quality, apparent ileal absorption and activity of antioxidant enzymes were accessed.3. A data showed that broilers receiving high-CHC had higher body weight, weight gain and better feed conversion ratio as compared to low-CHC at 21 d-old. On day 42, the feed conversion ratio was improved for birds supplemented with high-CHC in diets containing med-ZHC, as compared to low-CHC.4. Dietary Cu increased the redness of breast colour at the level of high-CHC compared to low-CHC. Greater results were observed on carcase traits for the med-ZHC group as compared to low- or high-ZHC. The ceruloplasmin activity in serum increased in the high-CSM diets containing high-ZSM as compared to low-CSM. The AIA of Cu was higher in broilers supplemented with high-CHC containing med-ZHC as compared to low-CHC. Otherwise, the AIA of Zn increased in broilers fed low-CHC containing low- or med-ZHC as compared to high-CHC.5. The trial showed that mineral trace supplementation of broilers diets with high-CHC (150 mg/kg) and low-ZHC (80 mg/kg) was a good alternative to replace sulphate mineral sources in diets.

Effects of dietary alfalfa protein concentrate on lipid metabolism and antioxidative status of serum and composition and fatty acid profile and antioxidative status and dietetic value of muscles in broilers

The aim of this study was to determine the effect of addition of alfalfa protein concentrate (APC) at the dose of 15 g or 30 g per 1 kg on the chemical composition, fatty acid profile, dietary value, and antioxidant status in muscles and serum of Ross 308 chickens. The experiment involved 150 1-day-old Ross 308 broiler chickens allocated into 3 groups in 5 replications (10 birds per pen). A 1-way system with 2 levels of APC, 15 g or 30 g per 1 kg of a complete diet, was used. Group C receiving a standard feed mixture without APC was the control. The addition of 15 and 30 g APC increased the CP content in the breast muscle and in the thigh muscle, and reduction in the cholesterol and fat level was noted. Higher content of polyunsaturated fatty acids from the n-6 group was noted in the breast muscles of the 30-g APC-supplemented chickens. The thigh muscles with APC were characterized by more favorable values of the atherogenic index, thrombotic index, and hypocholesterol-to-hypercholesterol ratio.The supplementation with 30 g APC reduced the cholesterol and triacylglycerol levels, increased the high-density lipoprotein level, and decreased the low-density lipoprotein level and improved the antioxidant parameters in plasma (increase in superoxide dismutase and in glutathione peroxidase and reduction of malondialdehyde), compared with group C. The results of this study indicate that the supplementation with 30 g APC improved the metabolic functions of the organism, meat resistance to oxidative processes, and the composition and profile of fatty acids. Therefore, APC can be a potential alternative to synthetic feed additives and soya protein in production of healthier poultry meat.

Effects of Saccharomyces cerevisiae and phytase co-fermentation of wheat bran on growth, antioxidation, immunity and intestinal morphology in broilers

OBJECTIVE

The aim of this study was to investigate the effects of different amounts of wheat bran (WB) inclusion and postbiotics form by Saccharomyces cerevisiae and phytase cofermented wheat bran (FWB) on the growth performance and health status of broilers.

METHODS

Study randomly allocated a total of 300 male broilers to a control and 4 treatment groups (5% WB, 5% FWB, 10% WB, and 10% FWB inclusion, respectively) with each pen having 20 broilers and 3 pens per treatment.

RESULTS

The WB does not contain enzymes, but there are 152.8, 549.2, 289.5, and 147.1 U/g dry matter xylanase, protease, cellulase and β-glucanase in FWB, respectively. Furthermore, FWB can decrease nitric oxide release of lipopolysaccharide stimulated chicken peripheral blood mononuclear cells by about two times. Results show that 10% FWB inclusion had significantly the highest weight gain (WG) at 1 to 21 d; 5% FWB had the lowest feed conversion rate at 22 to 35 d; 10% WB and 10% FWB inclusion have the highest villus height and Lactobacillus spp. number in caecum; and both 5% and 10% FWB can increase ash content in femurs. Compared to control group, all treatments increase mucin 2, and tight junction (TJ), such as occludin, claudin-1, zonula occludens-1, and mRNA expression in ileum by at least 5 folds. In chicken peripheral blood mononuclear cells, nicotinamide adenine dinucleotide phosphate-oxidase-1 mRNA expression decreases from 2 to 5 times, and glutamate-cysteine ligase catalytic subunit mRNA expression also increases in all treatment groups compared to control group. The mRNA expression of pro-inflammatory cytokines, including interleukin-6 (IL-6), nuclear factor-κB, and IL-1β, decreases in 5% and 10% FWB groups compared to control group.

CONCLUSION

To summarize, both WB and FWB inclusion in broilers diets increase TJ mRNA expression and anti-oxidation and anti-inflammation, but up to 10% FWB groups have better WG in different stages of broiler development.

Evaluation of Heavy Metal Content in Feed, Litter, Meat, Meat Products, Liver, and Table Eggs of Chickens

We assessed the concentrations of Fe, Cu, Zn, Mn, Se, Co, Cr, Pb, Cd, and Ni in chicken meat and meat products, feed, and litter, as well as laying hens' eggs, feed and litter to monitor the quality of products on the market and their safety for human consumption as judged by recommended daily allowance (RDA) and tolerable upper levels. Samples were chosen as the most popular poultry products in Saudi Arabia. A total of 45 broiler samples of frozen or fresh meat, liver, burger, or frankfurter were chosen from the same brand. Additionally, 60 table eggs from four commercial brands were collected, and the edible parts of these were used to determine levels of minerals and toxic elements. Furthermore, 30 feed and litter samples were collected from the starter, grower, and layer diets of broilers and laying hens. The results indicated that there were significant levels of most of the trace elements and heavy metals in the different meat sources. Furthermore, the liver contained the highest levels of elements, except for Cr, Co, and Ni. The highest Cr level was detected in the fresh meat, followed by frozen meat. Trace elements (Mn and Co) and heavy metals (Ni and Pb) were not detected in either the frozen or the fresh meat. The chicken burger and the frankfurter exhibited similar trace-element and heavy-metal contents, except for Zn and Mn, as the frankfurter showed higher concentrations than the burger. Differences in most of the trace and toxic elements among the different sources of eggs were not found to be significant, except for Zn. Differences between the broiler meat and table eggs were only substantial for Fe and Zn. Fe was significantly higher in meat than in eggs, and the opposite trend was found for Zn. The liver contained higher heavy metals than the eggs, except for Cr. In addition, the burger had higher concentrations of essential (Cu and Co) and heavy metals (Pb and Ni) than the eggs but had lower levels of Zn and Cr. The frankfurter exhibited significantly higher levels of Fe, Cu, Mn, Co, Pb, and Ni than the eggs but lower levels of Zn and Cr. To summarize, Cd, Pb, As, and Se were not detected in the broiler meat or eggs, indicating no risks from these toxic elements. Conversely, the liver exhibited the highest content of heavy metals, except for Cr, indicating that the intake of Pb and Cd was above the recommended daily allowance (RDA) for adults. The meat products exhibited higher Pb, Cd, and Ni levels than the broiler meat and the table eggs, suggesting that they posed a health threat to humans, and the intake of Pb in the meat products was higher than the RDA. Thus, chicken meat and table eggs, which are primary protein sources, are safe sources of human nutrition, while liver and meat products may present potential health hazards through the food chain.

Microbial and Fungal Phytases Can Affect Growth Performance, Nutrient Digestibility and Blood Profile of Broilers Fed Different Levels of Non-Phytic Phosphorous

Simple Summary

To reduce the environmental pollution is a must to preserve the health of the world. The environmental impact of poultry farming is receiving an increasing attention due to several emissions among these is phosphorus. This element is in general present in the commercial diets of broilers or laying hens in an amount exceeding the real needing of the animals, and, therefore, a great amount of phosphorus ends in the excreta. Thus, optimizing the amount of phosphorous in the diets of poultry could partially alleviate the environmental impact of these farms.

Abstract

A total of 420 day old chicks were divided into seven groups (5 replicates of 12 chicks/group) fed isoproteic and isoenergetic diets. The control group was fed diets containing 0.50%, 0.45% and 0.40% of non-phytic phosphorous (nPP) in starter (1–35), grower (37–56) and finisher (57–64 d) periods, respectively. The three intermediate nPP (IntnPP) groups were fed diets with 0.40%, 0.35% and 0.30% nPP according to the growth period and were submitted to three dietary treatments: unsupplemented; supplemented with 500 FTU/kg diet of an Aspergillus niger phytase (IntnPP_fp) and supplemented with 500 FTU/kg diet of an Escherichia coli phytase (IntnPP_bp). The three low nPP groups fed diets contained 0.30%, 0.25% and 0.20% nPP and were submitted to the same dietary treatments than IntnPP to obtain LnPP, LnPP_fp and LnPP_bp groups. IntnPP and LnPP groups had lower body weight gain and feed, crude protein (CP) and metabolizable energy (ME) intake (p < 0.05) than the control. Feed conversion ratio of IntnPP was more favorable (p < 0.01) than the LnPP group. CP and ME conversion ratios worsened (p < 0.01) in IntnPP and LnPP groups in comparison to the control. The nPP conversion ratio improved (p < 0.01) from the control to the LnPP group. Fungal phytase reduced (p < 0.05) feed, CP, ME and nPP intake than the bacterial one. IntnPP and LnPP diets had a lower digestibility of CP (p < 0.01) and CF (p = 0.01) than the control. IntnPP and LnPP groups showed a higher (p < 0.05) economic efficiency than the control. Blood total protein was the lowest (p < 0.05) in the LnPP group, the control group showed the lowest (p < 0.05) level of albumin and IntnPP group had the lowest (p < 0.01) globulin level. The use of bacterial phytase increased (p < 0.01) total protein and globulin and decreased (p < 0.05) the plasma cholesterol in comparison to fungal phytase. Decreasing nPP levels in colored slow-growing broilers diet negatively affects growth performance and the use of phytase can partly alleviate these negative effects, but the efficiency of different enzyme sources (bacterial or fungal) was tied to the dietary nPP levels.

Effect of Different Levels of Multienzymes on Immune Response, Blood Hematology and Biochemistry, Antioxidants Status and Organs Histology of Broiler Chicks Fed Standard and Low-Density Diets

This study was executed to investigate the effect of supplementing three multienzyme levels (0, 0. 1, and 0.2%) with two types of diet [standard diet (SD) vs. low-density diet (LDD)] on immune response, blood hematology and biochemistry, antioxidant status, and organ histology of broilers during 1–38 days of age. A total of 216 unsexed 1-day-old Arbor Acres broiler chicks were randomly distributed, on a factorial design (2 × 3), to six treatments each with six replicates. There were six chicks per replicate. Results showed that LDD significantly decreased body weight gain (BWG) of broilers, but did not affect the European Production Efficiency Index (EPEI). Addition of multienzymes at both levels (0.1 and 0.2%) significantly increased BWG and improved EPEI, compared to the control diet. Alanine aminotransferase (ALT), aspirate aminotransferase (AST), malondialdehyde (MDA), lymphocyte, lymphocyte transformation test (LTT), and phagocyte activity (PA) were significantly higher for LDD than the SD, but eosinophil was lower. Supplementation of multienzymes significantly decreased ALT, AST, and MDA, compared to the control group, but increased packed cell volume (PCV), hemoglobin (Hgb), lymphocytes, and monocytes. Immune organs, such as spleen, thymus, and the bursa of Fabricius were significantly increased with multienzyme supplementation. It could be concluded that multienzyme supplementation at either 0.1 or 0.2% to SD or LDD improved EPEI and immune status of broiler chicks.

Fatty acid profile, antioxidative status and dietary value of the breast muscle of broiler chickens receiving glycine-Zn chelates

In the present study we aimed to examine the effect of glycine-Zn chelates (ZnGly) used in amounts corresponding to 0, 100, 50 or 25% of the requirement of this element on the fatty acids profile, antioxidative status, and dietetic value (atherogenic index (AI), thrombogenic index (TI), hypocholesterolemic/hypercholesterolemic ratio (h/H)) of breast muscles in broiler chickens. Two hundred 1-day-old Ross 308 male chicks were split into four equipotent experimental groups (assigned to 20 cages, 10 chicks in each, replicated five times): control, ZnGly-100, ZnGly-50 and ZnGly-25. The broilers received feed and water ad libitum. The experiment lasted 42 days. Significant differences in the content of respective fatty acids in the meat of chickens receiving ZnGly were observed in comparison to the control group; but they were not directional changes. A positive effect (P &lt; 0.05) of Zn-Gly on certain indices of meat determined by the oxidoreductive status of the body or regulating such status was noted: superoxide dismutase, catalase and malondialdehyde. A significant effect of ZnGly on the dietetic value of broiler chickens’ breast meat was noted: the highest (P &lt; 0.05) AI value was found in the ZnGly-50 and ZnGly-25 groups, and TI value in the ZnGly-25 group. The h/H relationship can be presented as ZnGly-25 &lt; ZnGly-50 &lt; ZnGly-100 &lt; control group. To improve the dietetic value and to increase the oxidative stability of breast muscle meat, broiler chickens must receive ZnGly in an amount corresponding to more than 25% of the requirement of this element.