Review on the role of dietary zinc in poultry nutrition, immunity, and reproduction

CYP24A1 and TRPC3 Gene Expression in Kidneys and Their Involvement in Calcium and Phosphate Metabolism in Laying Hens

Ca and P homeostasis across the egg-laying cycle is a complex process involving absorption in the small intestine, reabsorption/excretion in the kidneys, and eggshell gland secretion. Diets with inadequate calcium and phosphorus can interfere with their absorption and digestibility, resulting in eggshell quality losses and reduced productive life, affecting egg production and welfare. A better understanding of gene expression profiles in the kidneys of laying hens during the late egg-laying period could clarify the renal role in mineral metabolism at this late stage. Therefore, the performance, egg quality and bone integrity-related traits, and expression profiles of kidney candidate genes were evaluated in 73-week-old laying hens receiving different Ca and P ratios in their diet: a high Ca/P ratio (HR, 22.43), a low ratio (LR, 6.71), and a medium ratio (MR, 11.43). The laying hens receiving the HR diet had improved egg production and eggshell quality traits compared to the other two groups. Humerus length was shorter in the HR than in the other groups. The CYP24A1 and TRPC3 genes were differentially expressed (p.adj ≤ 0.05) among the groups. Therefore, their expression profiles could be involved in calcium and phosphate transcellular transport in 73-week-old laying hens as a way to keep mineral absorption at adequate levels.

Complexed amino acid minerals vs. bis-glycinate chelated minerals: Impact on the performance of old laying hens

The present study was to evaluate the effect of trace minerals (Zn, Mn, and Cu) from complexed amino acid minerals (ZMCAA) and bis-glycinate chelated minerals (ZMCGly) in laying hen diets on performance, internal and external egg quality, yolk mineral deposition, intestinal morphometry, and bone characteristics. From 78 to 98 weeks of age, 400 White LSL-Lite strain laying hens were distributed in a randomized design with 4 treatments with 10 replicates per treatment. Treatments were distributed in a 2 × 2 factorial arrangement using either Zn, Mn, and Cu of ZMCAA or ZMCGly source at 2 levels: low (20, 20, and 3.5 mg/kg of Zn, Mn, and Cu, respectively) or high (40, 40, and 7 mg/kg of Zn, Mn, and Cu, respectively). The analysis of variance was performed, and in cases where differences were observed, the means were compared using Tukey's test (P < 0.05). The source and level of trace mineral supplementation had a significant impact on the performance of laying hens. Hens fed ZMCAA had higher egg production (P = 0.01), egg weight (P = 0.02), egg mass (P = 0.01), and lower feed conversion ratio (P = 0.05) compared to those fed ZMCGly. The ZMCAA supplementation showed higher albumen height (P = 0.01), albumen weight (P = 0.01), and eggshell thickness (P < 0.01). The deposition of Zn (P < 0.01), Mn (P < 0.01), and Cu (P < 0.01) in the egg yolk was greater for hens received ZMCAA. Tibia weight (P = 0.04) and bone densitometry (P < 0.01) in the tibia were higher with ZMCAA supplementation. In the small intestine, ZMCAA resulted in longer villi (P = 0.02) and shorter crypt depth (P = 0.01) in the duodenum. Jejunum and ileum measurements were influenced by the level and source of trace minerals (P < 0.05). Laying hens fed ZMCAA exhibited superior performance, egg quality, deposition of trace minerals in the egg yolk, and bone density compared to hens fed ZMCGly. In this study, older laying hens supplemented with ZMCAA at lower levels demonstrated adequate levels of supplementation.

Effect of Zinc Amino Acid Complexes on Growth Performance, Tissue Zinc Concentration, and Muscle Development of Broilers

The present study aimed to evaluate the effects of zinc amino acid complexes on growth performance, tissue zinc concentration, and muscle development in broilers. A total of 504 day-old male arbor acres broilers were randomly divided into seven treatments (fed with a basal diet or a basal diet supplemented with 120 mg kg-1 Zn as ZnSO4, 30, 60, 90 or 120 mg kg-1 Zn as ZnN, or 30 mg kg-1 Zn as ZnA separately). Each group had six replicates, with 12 birds per replicate. The results showed that the addition of 60 mg kg-1 ZnN significantly increased (P < 0.05) the average daily gain (ADG) and breast muscle percentage of broilers. Zinc concentration of ZnN and ZnA added groups were higher than (P < 0.05) that in the Zn sulfate group under the same addition dose. Except for the 30 mg kg-1 ZnN group, the muscle fiber diameter and cross-sectional area (CSA) were significantly increased (P < 0.05) in the ZnN addition groups. Compared with the basal diet group, adding ZnN significantly increased (P < 0.05) the expression of MTOR, MYOD, and MYOG at day 21 and decreased (P < 0.05) the expression of Atrogin-1. The expression levels of AKT, MTOR, P70S6K, and MYOD were increased at day 42, while the expression levels of MuRF1 and Atrogin-1 were decreased. Adhesion, backbone regulation of actin, MAPK, mTOR, and AMPK were significantly enriched as indicated by KEGG pathway enrichment analysis. In conclusion, zinc amino acid complexes could improve growth performance, tissue zinc concentration, and regulate breast muscle development.

Unexpected Cu and Zn speciation patterns in the broiler feed-animal-excreta system revealed by XAS spectroscopy

Trace minerals such as copper (Cu) and zinc (Zn) are animal nutrition supplements necessary for livestock health and breeding performance, yet they also have environmental impacts via animal excretion. Here we investigated changes in Cu and Zn speciation from the feed additive to the broiler excreta stages. The aim of this study was to assess whether different Cu and Zn feed additives induce different Cu and Zn speciation patterns, and to determine the extent to which this speciation is preserved throughout the feed-animal-excreta system. Synchrotron-based X-ray absorption spectroscopy (XAS) was used for this investigation. The principal findings were: (i) in feed, Cu and Zn speciation changed rapidly from the feed additive signature (Cu and Zn oxides or Cu and Zn sulfates) to Cu and Zn organic complexes (Cu phytate and Zn phytate). (ii) in the digestive tract, we showed that Cu and Zn phytate were major Cu and Zn species; Cu sulfide and Zn amorphous phosphate species were detected but remained minor species. (iii) in fresh excreta, Cu sulfide and Zn amorphous phosphate were major species. These results should help to: (i) enhance the design of future research studies comparing different feed additive performances; (ii) assess Cu and Zn bioavailability in the digestive tract; (iii) gain further insight into the fate of Cu and Zn in cultivated soils when poultry manure is used as fertilizer.

Effect of zinc hydroxychloride supplementation combined with an anticoccidial drug on Eimeria tenella infection in broiler chickens

Background and Aim

Eimeria tenella is a causative agent of avian cecal coccidiosis resulting in bleeding, diarrhea, weight loss, high morbidity, and mortality in chickens. Zinc supplementation increases body weight gain, reduces mortality, and improves some immune response parameters of broilers infected with E. tenella. This study aimed to investigate the effects of zinc hydroxychloride (ZnOHCl) supplementation and ZnOHCl combined with an anticoccidial drug on E. tenella infection in broiler chickens.

Materials and Methods

Forty one-day-old broilers were randomly divided into five groups, the study was replicated twice and had four chickens per replicate. Group 1 was an uninfected and unmedicated control group, and Group 2 was an infected but unmedicated control group. Group 3 was infected and treated with 120 mg/kg ZnOHCl, Group 4 was infected and medicated with 7 mg/kg toltrazuril (TOL), and Group 5 was infected and treated with 120 mg/kg ZnOHCl and 7 mg/kg TOL. Body weight gain, feed intake, and feed conversion ratio were monitored on days 15, 21, and 28. Oocyst shedding, hematological data, and lesion scores were analyzed on 7 days post-infection.

Results

The average weight gain, feed intake, and packed cell volume of chickens treated with ZnOHCl and TOL were significantly higher than those of the infected and unmedicated controls (p ≤ 0.05). Lesion scores, oocyst output, and lymphocytes of the chickens treated with ZnOHCl and TOL were significantly lower than those of the infected and unmedicated controls (p ≤ 0.05).

Conclusion

This study demonstrated that zinc supplementation alone reduced only oocyst output. However, growth performance, lesion scores, and oocyst output were affected by the combination of ZnOHCl and TOL supplementation. This suggests that ZnOHCl supplementation combined with an anticoccidial drug can improve growth performance and lessen the severity of E. tenella infection.

Influence of water quality and pollution on broiler's performance, vaccine and antibiotic efficiencies

Good water quality for livestock is critical for preserving animal health, ensuring the quality of animal products, supplying safe food, and increasing food production economics. Higher water levels of toxic compounds than permitted can impair meat, fat, eggs, and milk production, lower fertility, and represent public health hazards. Water picks up pollutants from its surroundings and those caused by animal and human activities. Many physicochemical parameters were used to ensure water quality, including pH, salt, taste, color, alkalinity, odor, and hardness. Water quality, directly and indirectly, impacts livestock performance and, thus, the poultry industry. Employing drinking water as a carrier of drugs still faces substantial barriers. The effectiveness of vaccinations and drugs is affected by inadequate water quality. Furthermore, contaminated water and poor nutrition negatively affect broiler chicken immunity, survival, and production. Antibiotics are widely utilized in poultry production to preserve animal health and growth. They can eliminate harmful bacteria in the gut, reduce the load on the immune system, optimize the digestive system, and boost growth performance. However, the abuse of antibiotics in animal agriculture has resulted in antibiotic-resistant infections threatening people and animals. As a result of its positive impact on the metabolome and gut microbiome, the natural antimicrobial combination could be used as an alternative; improving broiler chicken growth performance without negatively affecting the environment is currently paramount.

Effects of dietary zinc chloride hydroxide and zinc methionine on the immune system and blood profile of healthy adult horses and ponies

The effects of dietary zinc on the immune function of equines have not been evaluated in detail so far. In the present study, eight healthy adult ponies and two healthy adult horses were fed a diet supplemented with either zinc chloride hydroxide or zinc methionine in six feeding periods of four weeks each (according to maintenance zinc requirement, 120 mg zinc/kg dry matter, and 240 mg zinc/kg dry matter, for both dietary zinc supplements, respectively). All animals received the six diets, with increasing amounts of zinc chloride hydroxide in the feeding periods 1-3, and with increasing amounts of zinc methionine in the feeding periods 4-6. At the end of each feeding period, blood samples were collected for a blood profile and the measurement of selected immune variables. Increasing dietary zinc chloride hydroxide doses increased the glutathione concentrations in the erythrocyte concentrate and the glutathione peroxidase activity in the erythrocyte lysate, decreased the numbers of total leukocytes and granulocytes in the blood, and also decreased the interleukin-2 concentrations in the plasma of the animals. The dietary supplementation of increasing doses of zinc methionine enhanced the mitogen-stimulated proliferative activity of peripheral blood mononuclear cells, and decreased the glutathione concentrations in the erythrocyte concentrate and the glutathione peroxidase activity in the plasma of the animals. The percentage of blood monocytes with oxidative burst after in vitro stimulation with E. coli decreased with increasing dietary zinc concentrations, independently of the zinc compound used. The blood profile demonstrated effects of the zinc supplements on the red blood cells and the bilirubin metabolism of the horses and ponies, which require further investigation. Overall, high doses of dietary zinc modulate the equine immune system, for the most part also depending on the zinc compound used.

Impact of Maternal and Offspring Dietary Zn Supplementation on Growth Performance and Antioxidant and Immune Function of Offspring Broilers

The current study investigated the effects of the maternal Zn source in conjunction with their offspring’s dietary Zn supplementation on the growth performance, antioxidant status, Zn concentration, and immune function of the offspring. It also explored whether there is an interaction between maternal Zn and their offspring’s dietary Zn. One-day-old Lingnan Yellow-feathered broilers (n = 800) were completely randomized (n = 4) between two maternal dietary supplemental Zn sources [maternal Zn−Gly (oZn) vs. maternal ZnSO4 (iZn)] × two offspring dietary supplemental Zn doses [Zn-unsupplemented control diet (CON), the control diet + 80 mg of Zn/kg of diet as ZnSO4]. oZn increased progeny ADG and decreased offspring mortality across all periods, especially during the late periods (p < 0.05). The offspring diet supplemented with Zn significantly improved ADG and decreased offspring mortality over the whole period compared with the CON group (p < 0.05). There were significant interactions between the maternal Zn source and offspring dietary Zn with regards to progeny mortality during the late phase and across all phases as a whole (p < 0.05). Compared with the iZn group, the oZn treatment significantly increased progeny liver and serum Zn concentrations; antioxidant capacity in the liver, muscle, and serum; and the IgM concentration in serum; while also decreasing progeny serum IL-1 and TNF-α cytokine secretions (p < 0.05). Similar results were observed when the offspring diet was supplemented with Zn compared with the CON group; moreover, adding Zn to the offspring diet alleviated progeny stress by decreasing corticosterone levels in the serum when compared to the CON group (p < 0.05). In conclusion, maternal Zn−Gly supplementation increased progeny performance and decreased progeny mortality and stress by increasing progeny Zn concentration, antioxidant capacity, and immune function compared with the same Zn levels from ZnSO4. Simultaneously, Zn supplementation in the progeny’s diet is necessary for the growth of broilers.

Meta-analysis of Zinc Supplementation on Laying Performance, Egg Quality Characteristics, and Blood Zinc Concentrations in Laying Hens

There are inconsistent results on the influence of zinc (Zn) supplementation levels on productive indices of laying hens. This study, therefore, uses meta-analysis to synthesis evidence on the effect of inclusion of Zn in chicken diets on performance, egg quality, and blood Zn status of laying hens. Eleven studies were identified and used to analyze the effect of diets with or without Zn supplementation on feed intake, feed conversion ratio (FCR), hen day egg production (HDEP), egg weight (EW), egg mass (EM), Haugh unit (HU) scores, eggshell thickness (EST), eggshell weight (ESW), and blood Zn concentrations in laying hens. Data extracted from the 11 studies included in the meta-analysis were pooled using a random-effects model and expressed as standardized mean differences (SMDs) at a 95% confidence interval (CI). Results indicate that dietary Zn supplementation reduced FCR (SMD =  - 0.50 g feed/g egg; 95% CI: - 0.68 to - 0.31) and increased HDEP (SMD = 0.33%; 95% CI: 0.18 to 0.48), EW (SMD = 0.14 g; 95% CI: 0.03 to 0.25) and EM (SMD = 0.58 g/hen/day; 95% CI: 0.22 to 0.95), HU (SMD = 0.64; 95% CI: 0.42 to 0.85), EST (SMD = 0.84 mm; 95% CI: 0.45 to 1.23), and plasma Zn concentration (SMD = 4.20 mg/dl; 95% CI: 2.99 to 5.40) compared with the controls. In contrast, feed intake and ESW were not significantly different from controls. Restricted subgroup analysis indicated that chosen moderators (age of hen, inclusion level, chicken breed/strain, and supplementation duration) influenced the results of this meta-analysis. There was evidence of significant heterogeneity, and meta-regression indicated that moderators explained most of the sources of heterogeneity. We conclude that dietary zinc supplementation had positive effect on feed conversion ratio, laying performance, aspects of egg quality traits, and blood zinc concentrations in laying hens. The findings from this meta-analysis will help in policy advancements and sustainable use of zinc in the egg production industry.

Comprehensive Approaches of Nanoparticles for Growth Performance and Health Benefits in Poultry: An Update on the Current Scenario

Currently, providing nutritious food to all people is one of the greatest challenges due to rapid human population growth. The global poultry industry is a part of the agrifood sector playing an essential role in food insecurity by providing nutritious meat and egg sources. However, limited meat production with less nutritional value is not fulfilling the higher market demands worldwide. Researchers are focusing on nanobiotechnology by employing phytosynthesized mineral nanomaterials to improve the growth performance and nutritional status of broilers as these mineral nanoparticles are usually absorbed in greater amounts from the gastrointestinal tract and exert enhanced biological effects in the target tissues of animals with greater tissue accumulation. These mineral nanoparticles are efficiently absorbed through the gastrointestinal tract and reach essential organs via blood. As a result, it enhances growth performance and nutritional value with less toxicity and tremendous bioavailability properties. In this review, the research work conducted in the recent past, on the different aspects of nanotechnology including supplementation of mineral nanoparticle in diet and their potential role in the poultry industry, has been concisely discussed.

Zinc supplementation improves antioxidant status, and organic zinc is more efficient than inorganic zinc in improving the bone strength of aged laying hens

Background

There have been some reports indicating that supplementation of zinc could alleviate the negative effects of age on egg quality in laying hens. However, information regarding these positive effects on health and zinc deposition in the body is limited.

Objectives

The aim of the present study was to investigate the effect of organic and inorganic sources of zinc on the antioxidant activity, bone strength, and zinc deposition in the tissues of older laying hens.

Methods

In a completely randomized design, 175 Leghorn laying hens (w36) aged 80 weeks were allocated into seven treatment groups and five replications: control (without zinc supplementation), zinc sulphate treatments (15, 30, and 45 mg/kg), and organic zinc treatments (15, 30, and 45 mg/kg).

Results

There was a significant increase in feed intake in the zinc sulphate and organic zinc treatments compared to the control treatment (p < 0.05). The egg mass in organic and sulphate zinc showed a significant increase. The feed conversion ratio was decreased significantly in the organic zinc treatments (p < 0.05). Both organic and sulphate zinc supplements enhanced serum superoxide dismutase activity as an antioxidant index (p < 0.05). The cortical thickness of the tibia was improved in laying hens receiving 30 mg/kg organic zinc. Supplementation of zinc could lead to an increase in zinc deposition in tissues, and organic zinc boosts bone strength.

Conclusion

Zinc supplementation can improve antioxidant activity, feed intake, and feed conversion ratio and enhance egg mass and optimal absorption of zinc in tissues. The use of 30 mg/kg organic zinc is recommended for improving the cortical thickness of the tibia in aged laying hens.

Relative Bioavailability of Broiler Chickens Fed with Zinc Hydroxychloride and Sulfate Sources for Corn-Soybean Meal

This study was conducted to determine relative bioavailability (RBV) of basic zinc chloride (BZC) compared to zinc sulfate monohydrate (ZSM) for broilers. A randomized design involving a 2 × 3 factorial arrangement of the different treatment regimens plus one negative control was set up for this study. A total of 630 newly hatched male AA broiler chicks were randomly allocated to 42 different pens (15 chickens/pen) and assigned to 7 dietary treatments in a completely randomized design. The diet was supplemented with 0, 20, 40, or 80 mg of Zn mg/kg of feed in the form of ZSM or BZC. The results showed that zinc supplementation altered average daily gain (ADG) and feed conversion ratio (FCR) (P < 0.05) for both zinc sources. It was observed that the weight gain increased linearly (P < 0.01) and FCR decreased linearly as dietary BZC and ZSM concentration increased. Moreover, compared with chickens fed with ZSM, chickens fed with BZC had higher ADG and lower FCR from days 0 to 14 (P < 0.05), and higher activity of plasma alkaline phosphatase (ALP) (P < 0.05), total superoxide dismutase (T-SOD), and CuZn superoxide dismutase (CuZn-SOD) (P < 0.01) in the plasma of chickens fed with BZC at zinc level 80 mg/kg at day 14. The pancreas divalent metal-ion transporter-1 (DMT1) mRNA expression of chickens fed with BZC was found to be significantly enhanced at day 28, and the pancreas metallothionein (MT) mRNA expression for BZC fed group was also markedly increased at Zn levels of 20 and 40 mg/kg respectively. The relative bioavailability (RBV) of BZC (Zn sulfate 100%) based on ADG in the starter phase was 110.82%, whereas the tibia zinc content, as well as the activities of plasma ALP and CuZn-SOD, and the pancreas MT mRNA level were in the range between 108 and 119%. It was thus concluded that BZC was more efficacious than Zn sulfate and could serve as a potentially novel zinc source in the broilers.

Feeding Zinc-Biofortified Wheat Improves Performance, Nutrient Digestibility, and Concentrations of Blood and Tissue Minerals in Quails

The present study aimed to investigate the effects of feeding zinc (Zn)-biofortified wheat on performance, digestibility, and concentrations of minerals in quails. Zinc biofortification of wheat has been realized in the field by ergonomically applying Zn to foliar two and three times, which increased grain Zn from 18 mg/kg (control) to 34 and 64 mg/kg. A total of 180 quails were divided into six groups, each containing 30 birds, and fed diets containing wheat grain with either 18, 34, or 64 mg/kg with or without zinc picolinate (ZnPic) supplementation. Bodyweight, feed intake, feed efficiency, and cold carcass weights were greater (P = 0.0001) when the quails were fed a diet containing the biofortified wheat-containing 64 mg Zn/kg. Nitrogen, ash, Ca, P, Zn, Cu, and Fe retentions were greater with the Zn-biofortified wheat-containing 64 mg Zn/kg (P ≤ 0.026). The nutrient excretions were low with feeding a diet containing biofortified wheat-containing 64 mg Zn/kg (P ≤ 0.023). Serum, liver, and heart Zn concentrations increased with feeding biofortified wheat-containing 64 mg Zn/kg (P ≤ 0.002). Thigh meat Fe concentrations increased with increasing Zn concentrations of the wheat samples used (P = 0.0001), whereas the liver Cu concentrations decreased with feeding the wheat-containing 64 mg Zn/kg (P = 0.004). The Zn-biofortified wheat-containing greater Zn concentrations, particularly 64 mg Zn/kg, is a good replacement for corn in the poultry diet as long as its availability and low cost for better performance, greater digestibility, and elevated tissue Zn and Fe concentrations.

Effects of Zinc Methionine Hydroxy Analog Chelate on Laying Performance, Serum Hormone Levels, and Expression of Reproductive Axis Related Genes in Aged Broiler Breeders

Inorganic zinc (Zn) supplements are commonly used in poultry feeds, but their low utilization results in the increase of Zn excretion. Thus, to provide a new perspective for the substitution of inorganic Zn, a novel Zn methionine hydroxy analog chelate (Zn-MHA) was studied in the present study to evaluate its effects on laying performance, serum hormone indexes and reproductive axis-related genes in broilers breeders. A total of 480 Hubbard breeders (56-week-old) were fed a basal diet (containing 27.81 mg Zn/kg) without Zn addition for 2 weeks, and then allocated to 4 groups with 6 replicates (each replicate consisting of 10 cages and 2 breeders per cage) for 10 weeks. Four treatment diets given to broiler breeders included the basal diet added with 25, 50, and 75 mg/kg of Zn-MHA and 100 mg/kg of Zn sulfate (ZnSO₄). The laying rate, egg weight and feed conversation ratio increased in the 75 mg/kg Zn-MHA group compared to the ZnSO₄ group. The eggshell thickness was not decreased with the addition of 50 mg/kg and 75 mg/kg Zn-MHA in the diet compared to the 100 mg/kg ZnSO₄ group. There was a significant improvement in the reproductive performance of breeders in the 75 mg/kg Zn-MHA group, including the fertility and 1-day-old offspring weight. Besides, serum sex hormone levels including FSH and P₄ increased significantly in 75 mg/kg Zn-MHA group. No significant effect on the ovarian weight or the number of follicles in broiler breeders was observed by supplementing Zn-MHA. Compared to the 100 mg/kg ZnSO₄ group, dietary supplementation with 75 mg/kg of Zn-MHA showed an up-regulation of the FSHR mRNA in the granular layer of follicles. However, dietary supplementation of Zn-MHA had no effects on mRNA expressions of the ovarian LHR and PRLR genes. These findings reinforce the suggestion that Zn-MHA (75 mg/kg) could replace ZnSO₄ (100 mg/kg) as a Zn supplement in diet of broiler breeders, which resulted in better laying and reproduction performances by regulating the expression levels of reproductive axis related genes and serum hormone levels.

The Effects of Nano and Micro Particle Size of Zinc Oxide on Performance, Fertility, Hatchability, and Egg Quality Characteristics in Laying Japanese Quail

The current trial was conducted by using the 288 Japanese quails to evaluate the effects of a zinc-deficient diet supplemented with nano and micro zinc oxide on performance, fertility, hatchability, and egg quality characteristics. In this experiment, birds were randomly allocated to 9 dietary treatments includes diets supplemented with nano or micro particles of zinc oxide (amount of ZnO supplement for each treatment) to supply 49, 74, 99, and 124 mg zinc per kilogram of diet in a factorial arrangement (2 × 4) and a control non supplemented diet (24 mg/kg) with four replicates of eight birds (six females and two males) in each pen. Birds were fed the experimental diets from 47 to 75 days of age and had free access to water and feed during the experimental period. Results showed that Zn supplementation, regardless of particle size, improved the eggshell thickness (P < 0.01). A significant (P < 0.05) interaction was observed between zinc level and ZnO particle size for Shell breaking strength. Quails fed diets supplement with ZnO showed significantly higher egg weight and eggshell surface (P < 0.05) as compared with birds fed a non-supplemented control diet. Results obtained here showed that supplementation of nano ZnO enhanced fertility considerably. Application of non-linear quadratic models showed that the maximum egg production percentage was achieved when 67 or 72 mg/kg of dietary zinc was supplied from nano and micro ZnO, respectively. This result indicated that nano ZnO could reduce the zinc requirement in laying Japanese quail.

Effects of organic macro and trace minerals in fast and slower growing broiler breeders' diet on offspring growth performance and tibia characteristics

This study was designed to evaluate effects of source of macro and trace minerals (inorganic vs. organic) in fast and slower growing broiler breeders' diets on egg and hatchling mineral content and on offspring tibia morphological, biophysical, and mechanical characteristics. After 10 wk feeding the breeders (at 30 wk of age), eggs were collected and incubated. Eggs and hatchlings were analysed on mineral content. Male chickens were assigned to 32 pens with 12 chickens per pen. At approximately 1,700 and 2,600 gram BW, three chickens per pen were slaughtered. Tibia characteristics were determined. Organic minerals in the broiler breeder diet resulted in higher Fe and Se concentration in the egg and in higher Se concentration in the hatchling. Despite effects of mineral source on mineral concentration in the eggs and hatchlings were limited, organic minerals in the slower-growing broiler breeder diet resulted in higher offspring BW (d 42, Δ = 115 g; P = 0.03) and advanced tibia development (higher thickness (∆ = 0.38 cm; P < 0.001), osseous volume (∆ = 5.1 cm³; P = 0.01), and mineral density (Δ = 0.13 g/cm³; P = 0.03) at 2,600 g BW), but this was not observed in fast-growing chickens. This suggests that 1) the difference in feed intake of the breeders between strains might affect offspring performance, which might indicate that current slower-growing breeder diets might be suboptimal in minerals or that transgenerational mineral availability in slower growing chickens appears to be more effective on bone development, which might be related to time available for bone development. 2) transgenerational mineral availability in offspring appears to play a role via other mechanisms than via absolute mineral concentrations.

Effect of methionine chelated Zn and Mn and corn particle size on Large White male turkey live performance and carcass yields

Most turkey research has been conducted with a regular corn particle size set through phase-feeding programs. This study's first objective was to determine the effect of increasing corn particle size through the feed phases on performance, processing yield, and feed milling energy usage in Large White commercial male turkey production. Zinc (Zn) and manganese (Mn) are essential microminerals for animals' healthy growth. The source in which these elements are supplied to the bird will determine their bioavailability, effect on bird growth, and subsequent environmental impact. This study's second objective was to measure both inorganic and chelated Zn and Mn sources on turkey performance, turkey carcass processing yields, and subsequent litter residues. Twelve hundred Nicolas Select male poults were randomly assigned to 48 concrete; litter-covered floor pens. The experimental design was a completely randomized block design with a 2 × 2 factorial arrangement of 2 sources of minerals (organic blend vs. inorganic) formulated to match breeder recommendations and 2 types of corn mean particle size (coarse corn [1,000-3,500 µm] vs. fine corn [276 µm]). The ASABE S319.4 standard was used to measure corn mean particle size. Bird performance, carcass processing yield, litter content of Zn and Mn, and pellet mill energy consumption were analyzed in SAS 9.4 in a mixed model. There was a reduction of pellet mill energy usage of 36% when coarse corn was added post-pelleting. Birds fed increasing coarse corn mean particle size were 250 g lighter on average in body weight (BW) than birds fed a constant control mean particle size. No difference was found in feed intake (FI) or feed conversion ratio (FCR). Birds fed methionine chelated Zn and Mn blended with inorganic mineral sources were 250 g heavier on average than birds fed only an inorganic source of minerals. In addition, feeding an organic blend of Zn and Mn resulted in greater breast meat yield. Litter from birds fed the control corn mean particle size, and inorganic minerals had a higher concentration of Zn in the litter but were not different when the chelated Zn/Mn were fed. In conclusion, increasing the corn mean particle size and adding it post pellet could save money during feed milling; however, birds might have a slightly lower BW. A combination of inorganic and chelated Zn and Mn may improve performance and increase total breast meat yields.

Effects of Zinc on Cell Proliferation, Zinc Transport, and Calcium Deposition in Primary Endometrial Epithelial Cells of Laying Hens In Vitro

For birds, the uterus is an important part for eggshell mineralization, and the establishment of the endometrial epithelial cell (EEC) model was beneficial to the study of uterine function. This study was conducted to establish a culture model of primary EECs of laying hens and explore the effects of zinc on primary EEC proliferation, zinc transport, and calcium deposition in vitro. The EECs were isolated and cultured via type I collagenase digestion, and in the logarithmic phase during 2-5 days, and then reached the plateau phase on the 7th day of inoculation. Results showed that the proliferation of EECs treated by 50 μM ZnSO₄ or zinc-methionine (Zn-Met) were markedly promoted at 24-h or 48-h treating time (P < 0.05). In later experiments, the EECs were divided into three groups, involving a control group (no zinc treated), ZnSO₄ group (50 μM zinc treated) and a Zn-Met group (50 μM zinc treated). Results showed the relative fluorescence intensity of Ca²⁺ in the Zn-Met group was significantly higher than that in the control group (P < 0.05). As for zinc transporters, it was only observed that mRNA levels of metallothionein (MT) in EECs showed a significant difference (P < 0.05) between the Zn-Met group and the control. In conclusion, the EECs of laying hens isolated by scraping and digested collagenase I were with better adherent growth. Moreover, Zn-Met can increase intracellular Ca²⁺ concentration and upregulate expressions of MT mRNA in the EECs of laying hens.

Efficacy of Trace Mineral-Amino Acid Complexes in a Necrotic Enteritis Challenge Model

Necrotic enteritis (NE) is a common and costly disease of poultry caused by virulent toxigenic strains of Clostridium perfringens. Although the importance of trace minerals for intestinal integrity and health is well documented, there is little information on their role in ameliorating the effects of NE. The two studies reported here examined the effects of replacing a portion of the dietary zinc (Zn), copper (Cu), and manganese (Mn) supplied as sulfates in the control diets with metal-amino acid-complexed minerals in a NE-challenge model consisting of coccidiosis and Clostridium perfringens. In a 28-day battery study, the treatments were the following: (1) no additional Zn or Mn, unchallenged (negative control); (2) no added Zn or Mn, challenged (positive control); (3) added ZnSO4 and MnSO4 at 100 ppm each, challenged; (4) additional ZnSO4 at 60 ppm, Availa-Zn at 40 ppm (Low), and MnSO4 at 100 ppm, challenged; (5) added ZnSO4 at 60 ppm, Availa-Zn at 60 ppm (high), and MnSO4 at 100 ppm, challenged; and (6) added ZnSO4 at 60 ppm, Availa-Zn at 40 ppm, MnSO4 at 60 ppm, and Availa-Mn at 40 ppm, challenged. None of the treatments ameliorated gross lesion scores, but all reduced NE-associated mortality compared with the positive control. At 28 days, the group supplemented with Availa-Zn at 40 ppm (low) had a lower body weight than challenged groups supplemented with Zn and the negative control. In a floor pen study, the five treatment groups were the following: (1) Zn, Mn, and Cu from sulfate sources at 100, 100, and 20 ppm respectively; (2) Zn, Mn, and Cu from sulfate sources at 40, 100, and 20 ppm, respectively, plus Zn from Availa-Zn at 60 ppm; (3) Zn and Mn from sulfate sources at 40 and 100 ppm, respectively, plus Zn from Availa-Zn at 60 ppm and Cu from Availa-Cu at 10 ppm; (4) Zn, Mn, and Cu from sulfate sources at 60, 60, and 20 ppm, respectively, plus Zn and Mn from Availa-Zn/Mn at 40 and 40 ppm, respectively; and (5) bacitracin methylene disalicylate at 55 g/metric ton with Zn, Mn, and Cu from sulfate sources at 100, 100, and 20 ppm, respectively (Zoetis, Inc., Kalamazoo, MI). None of the treatments reduced lesion scores. The Availa-Zn and Availa-Zn/Mn had lower mortality than the sulfate-supplemented feed, whereas Availa-Zn/Cu and bacitracin methylene disalicylate were intermediate and did not differ from the other groups. Considering both trials together, and by using NE mortality as the discriminating factor, we found that adding Zn and Mn exceeding National Research Council requirements reduced NE-associated mortality, and in the floor pen study, complexed Zn and complexed Zn plus Mn appeared to be superior to sulfates.

Anadara granosa shell powder improves the metabolism, testosterone level, and sound frequency of Pelung chickens

Background and Aim:

Pelung chickens make unique, pleasant, and rhythmic sounds in addition to having strong muscle mass. Performance is controlled by testosterone. A natural aromatase blocker is an agent capable of blocking the aromatase enzyme, which consequently prevents testosterone from being changed into estradiol. Such a condition results in consistently high testosterone levels. The aim of this study was to determine the effect of the administration of the shell powder of Anadara granosa on the testosterone level, frequency and quality of sounds, and metabolism of Pelung chickens within set parameters of thyroid hormone levels, the triiodothyronine (T₃)/thyroxine (T₄) ratio, and weight gain.

Materials and Methods:

This study used four Pelung chickens aged 14 months. Control data consisted of data before treatment (day 0). Shell powder of A. granosa was administered for 56 days. Body weight (BW) was measured, and blood samples were drawn. In addition, the sounds from Pelung chickens were recorded once every 2 weeks on days 14, 28, 42, and 56. The blood samples were analyzed using the enzyme immunoassay method to determine testosterone, T₃, and T₄ levels. The sounds of Pelung chickens were recorded using the Hagemon touch method and analyzed using the Audacity application.

Results:

The results showed a significant difference (p<0.05) in the levels of testosterone, BW, and sound frequency after the administration of A. granosa shell powder, but the administration did not have a significant effect on the levels of T₄ and T₃ hormones (thyroid hormone), T₃/T₄ ratio, or sound duration. The testosterone content and BW of Pelung chickens increased from day 14 to day 56, whereas T₃ was indicative of the same profile as the T₄ hormone. However, T₃ and T₄ levels and the T₃/T₄ ratio decreased and increased, respectively. The sound frequency of Pelung chickens increased from day 0 to day 14, although sound duration decreased.

Conclusion:

The administration of A. granosa shell powder at 0.9 mg/kg BW orally could improve the metabolism, testosterone level, BW, and sound frequency of Pelung chickens.

Reference intervals for Cu, Mg, and Zn in captive gyrfalcons and other falcon species in the United Arab Emirates

Falconry is a long-standing tradition in the United Arab Emirates (UAE), and in 2016, falconry was included by UNESCO in the list of intangible cultural heritage of humanity. The health and wellness of falconry raptors is a priority for the local culture; plasma chemistry analysis plays an important role in monitoring, assessing, and managing diseases in avian patients. Imbalances of Cu, Mg, and Zn have been linked to several diseases in avian species; therefore, determining the reference intervals (RIs) of these minerals has important implications in the clinical management of falcons. We determined the RIs in plasma for Cu, Mg, and Zn in captive (falconry-managed) falcons according to the Quality Assurance and Laboratory Standards Committee of the American Society for Veterinary Clinical Pathology, and the Clinical Laboratory Standards Institute guidelines. Blood chemistry analyses were carried out on 252 clinically healthy falcons examined at the Dubai Falcon Hospital in the UAE: 124 gyrfalcons (Falco rusticolus) and 128 falcons of other species. We observed no significant variation in RIs of Cu (1.5-7.0 µmol/L), Mg (0.49-0.78 mmol/L), or Zn (11.8-34.1 µmol/L) based on different species or sex.

Zinc hydroxychloride supplementation improves tibia bone development and intestinal health of broiler chickens

This study was conducted to investigate the effects of zinc (Zn), as a combination of oxide (ZnO) and sulfate (ZnSO₄), compared with incremental levels of zinc hydroxychloride (ZH) on tibia traits, intestinal integrity, expression of selected jejunal genes, cecal short chain fatty acids and microbial composition in broilers. Day-old male Ross 308 chicks (n = 784) were randomly allocated to seven dietary treatments, each replicated seven times with 16 chicks per replication. The dietary treatments included a negative control diet (NC) with no supplemental Zn, a positive control (PC) with 100 mg/kg supplemental Zn from an ionic bound source combination (50 mg/kg ZnO + 50 mg/kg ZnSO₄), and the NC diet supplemented with one of 20, 40, 60, 80, or 100 mg/kg Zn as ZH. The diets were fed over starter (1–14 d) and grower (14–35 d) phases, with tissue and digesta samples collected from 3 birds per replicate on days 14 and 35. The results showed that dietary Zn level had a significant effect on tibia breaking strength on d 35 (P < 0.05), and tibia Zn concentration both on d 14 and d 35 (P < 0.01). Dietary Zn levels linearly (P < 0.01) increased cecal lactic acid production, increased Lactobacillus, and decreased Bacillus and total bacteria counts (P < 0.05). Inclusion of 80 and 100 mg/kg Zn as ZH tended to upregulate the expression of claudin-1 (P = 0.088) and tight junction protein-1 (P = 0.086). The results obtained in this study suggest that a non-Zn supplemented diet can negatively influence tibia development and gut microbiota composition in broiler chickens. Higher supplemental Zn in the diet alters cecal microbiota population in favor of Lactobacillus and can decrease the total bacterial load. Supplemental Zn level in the feed have the potential to manipulate the jejunal gut integrity at a molecular level.

Intestinal digestibility of selected minerals, growth performance and meat quality in turkeys fed diets supplemented with different sources and levels of zinc

The aim of this study was to determine whether dietary supplementation with zinc oxide nanoparticales (NP-ZnO) as a substitute for the conventional ZnO affects the intestinal digestibility of selected minerals, growth performance and meat quality in turkeys. The replacement of ZnO with NP-ZnO had no effect on the intestinal digestibility of Zn, Cu, Fe and Ca, whereas the lowest dose of supplemental Zn reduced Zn digestibility. The applied inclusion levels and sources of Zn had no effect on the growth performance (except the feed intake) of turkeys, including liveability. No differences in the relative weights of the heart, spleen and bursa of Fabricius (except the liver), or the weights of the femur and tibia were found between the dietary treatments. Neither the dose nor the source of supplemental Zn influenced carcass dressing percentage or the share of breast, thigh and drumstick muscles in the carcass. In comparison with the highest and moderate doses of Zn, the lowest inclusion level of Zn contributed to increased yellowness of breast meat (P=0.005). The analyzed doses and sources of supplemental Zn exerted varied effects on the redox status of fresh and frozen breast meat. In conclusion, the growth performance of turkeys, carcass yield and composition as well as the redox status of fresh and frozen breast meat were generally similar, regardless of the dietary source and level of Zn. The beneficial effect of Zn addition at 100 mg/kg was improved Zn and Ca digestibility, and increased redness of breast meat.

The prophylaxis and treatment potential of supplements for COVID-19

The global impact of the new coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), infection that caused COVID-19 has been evident in the last few months from the unprecedented socioeconomic disruption to more than 600,000 deaths. The lack of vaccine and effective therapeutic agents for the disease prompted world-wide effort to test those antiviral therapeutics already in use for other diseases. Another interesting approach has been based on the pathological sequel of the disease that involve severe inflammatory reaction (or the cytokine storm) associated with pneumonia in critically ill patients. This article outlines the prophylaxis therapeutic potential of supplements vitamins and micronutrients in COVID-19. By ameliorating the inflammatory and oxidative stress associated with the disease and some direct antiviral effects, the application of these agents as adjuvants and other alternative approaches are discussed. Available clinical trials including those currently registered on these supplements are scrutinized.

RNA-based thermoregulation of a Campylobacter jejuni zinc resistance determinant

RNA thermometers (RNATs) trigger bacterial virulence factor expression in response to the temperature shift on entering a warm-blooded host. At lower temperatures these secondary structures sequester ribosome-binding sites (RBSs) to prevent translation initiation, whereas at elevated temperatures they "melt" allowing translation. Campylobacter jejuni is the leading bacterial cause of human gastroenteritis worldwide yet little is known about how it interacts with the host including host induced gene regulation. Here we demonstrate that an RNAT regulates a C. jejuni gene, Cj1163c or czcD, encoding a member of the Cation Diffusion Facilitator family. The czcD upstream untranslated region contains a predicted stem loop within the mRNA that sequesters the RBS to inhibit translation at temperatures below 37°C. Mutations that disrupt or enhance predicted secondary structure have significant and predictable effects on temperature regulation. We also show that in an RNAT independent manner, CzcD expression is induced by Zn(II). Mutants lacking czcD are hypersensitive to Zn(II) and also over-accumulate Zn(II) relative to wild-type, all consistent with CzcD functioning as a Zn(II) exporter. Importantly, we demonstrate that C. jejuni Zn(II)-tolerance at 32°C, a temperature at which the RNAT limits CzcD production, is increased by RNAT disruption. Finally we show that czcD inactivation attenuates larval killing in a Galleria infection model and that at 32°C disrupting RNAT secondary structure to allow CzcD production can enhance killing. We hypothesise that CzcD regulation by metals and temperature provides a mechanism for C. jejuni to overcome innate immune system-mediated Zn(II) toxicity in warm-blooded animal hosts.

Mineral requirements in ducks: an update

Mineral nutrition plays a critical role in growth and bone mineralization in meat ducks as well as reproductive performance in duck layers and duck breeders. In addition to improving production performance parameters, minerals are also essential to support several enzymatic systems to enhancing antioxidant ability and immune function. This review explores the biological function and metabolism of minerals in the body, as well as mineral feeding strategy of various species of ducks. Topics range from mineral requirement to the physiological role of macroelements such as calcium and phosphorus and microelements such as zinc and selenium, etc. As with the improvement of genetic evolution and upgrade of rearing system in duck production, mineral requirements and electrolyte balance are urgent to be re-evaluated using sensitive biomarkers for the modern duck breed characterized by the rapid growth rate and inadequate bone development and mineralization. For duck breeders, mineral nutrition is not only required for maximal egg production performance but also for maintaining normal embryonic development and offspring's performance. Therefore, the proper amounts of bioavailable minerals need to be supplemented to maintain the mineral nutritional state of duck species during all phases of life. In addition, more positive effects of high doses microelements supplementations have been revealed for modern meat ducks subjected to various stresses in commercial production. The nutritional factors of mineral sources, supplemental enzymes, and antinutritional factors from unconventional ingredients should be emphasized to improve the effectiveness of mineral nutrition in duck feed formulation. Organic mineral sources and phytase enzymes have been adopted to reduce the antagonistic action between mineral and antinutritional factors. Therefore, special and accurate database of mineral requirements should be established for special genotypes of ducks under different rearing conditions, including rearing factors, environmental stresses and diets supplemented with organic sources, phytase and VD₃.

Progress and Prospect of Essential Mineral Nanoparticles in Poultry Nutrition and Feeding-a Review

Nanobiotechnology is a growing field in animal and veterinary sciences for various practical applications including diagnostic, therapeutic, and nutritional applications. Recently, nanoforms or nanoparticles (NP) of essential minerals have been explored for growth performance, feed utilization, and health status of animals. Various mineral NP, such as calcium, zinc, copper, selenium, and chromium, have been studied in different farm animals including poultry. Because mineral NP are smaller in size, and show different chemical and physical properties, they are usually absorbed in greater amounts from gastrointestinal tract and exert enhanced biological effects in the target tissues of animals. In various studies, mineral NP have been comparatively studied relating to its larger inorganic and organic particles in poultry. There are contradictory findings among the studies on comparative improvement of production performance and other mineral functions perhaps due to different sizes, shapes, and properties of NP, and interactions of minerals present in basal diets. There are not many studies correlating physical and chemical properties of mineral NP and their biological functions in the body. Nonetheless, it appears that mineral NP have potential for their uses as mineral supplements in preference to inorganic mineral supplements for their better absorption avoiding antagonistic interactions with other minerals, growth performance, and physiological functions, especially at lower doses compared with the doses that are recommended for their larger particles. Supplementation of mineral NP in diets could be a promising option in the future. This review summarizes the studies of different essential mineral NP used as mineral supplements for feed intake, growth performance, egg production and quality, and blood variables in poultry.

Effect of Dietary Zinc Level on Egg Production Performance and Eggshell Quality Characteristics in Laying Duck Breeders in Furnished Cage System

In order to investigate the effect of dietary Zn levels on laying performance, eggshell quality, and eggshell microstructure in Muscovy duck breeders under furnished cages. Firstly, the effects of age (35 weeks vs 40 weeks) and rearing system (littered floor vs furnished cage) on eggshell quality of laying duck breeders were studied (Exp. 1). Then, a total of 324 30-week-old Muscovy duck breeders were allotted into 3 dietary Zn groups with 6 replicates (18 ducks per replicate), including 0 mg Zn/kg (control-Zn group, C-Zn), 40 mg Zn/kg (normal-Zn group, N-Zn), and 140 mg Zn/kg (high-Zn group, H-Zn). The experimental period for 6 weeks was divided into 3 periods of 30-32, 32-34, and 34-36 weeks of age (Exp. 2). In Exp. 1, duck breeder eggs in the furnished cage system had lower the average shell thickness than birds in the littered floor system at 40 weeks of age (P < 0.05), not at 35 weeks of age. In Exp. 2, N-Zn and H-Zn groups had greater egg weight, egg production, and egg to feed ratio of duck breeders than C-Zn group (P < 0.05). Additionally, H-Zn group had higher laying rate, qualified egg ratio, and Haugh unit as well as lower mammillary cone width than C-Zn group (P < 0.05), with no differences between C-Zn and N-Zn groups (P > 0.05). Diet supplemented with 140 mg Zn/kg increased shell thickness and palisade layer thickness of duck breeders at 36 weeks of age (P < 0.05), but not at 32 and 34 weeks of age. In conclusion, diets with 40 or 140 mg Zn/kg improved egg production performance and egg quality of laying duck breeders during 30-36 weeks of age in a furnished cage system. Dietary supplementation of 140 mg Zn/kg level increased the ultrastructural palisade layer thickness contributing to greater eggshell thickness of duck breeders at 36 weeks of age.

Impact of dietary nano-zinc oxide on immune response and antioxidant defense of broiler chickens

This study aimed to elucidate the response of broiler chickens to the dietary nano-zinc supplementation in terms of immune response and antioxidant activity. Ninety-one-day-old chicks (Ross 308) were randomly assigned to one of three dietary treatments in three replicates, in a feeding trial that lasted for 5 weeks. Birds were fed a basal diet supplemented with inorganic zinc oxide at 40 mg/kg diet (control), zinc oxide nanoparticles (ZnONPs) at 40 mg/kg diet (ZN1), or ZnONPs at 80 mg/kg diet (ZN2). Birds were injected with DNP-KLH at the 7th and 21st days from the beginning of the experiment, and blood samples were collected on days 7, 14, 21, 28, and 35 to determine the levels of immunoglobulin Y (IgY) and malondialdehyde as well as the antioxidant enzyme activities. Cellular immunity was assayed by estimation of phagocytic percentage and index of peripheral monocytes of blood and estimation of the T lymphocyte activity using a lymphocyte transformation test. The results showed that feeding broiler chickens a diet supplemented with ZnONPs increased (p < 0.05) the activity of superoxide dismutase and catalase and decreased the concentration of malondialdehyde compared to the control diet, without significant differences between NZ1 and NZ2 diets. Moreover, the chicks fed diets supplemented with ZnONPs showed a significant increase (p < 0.05) in serum IgY, total lymphocyte count, and macrophages compared to the control. A higher significant response for antibodies IgY concentration was observed in birds fed the NZ2 vs NZ1 diet. Also, there was a significant increase in phagocytic activity and phagocytic index in ZnONP-fed groups with a higher significance in the group fed NZ1 than with NZ2 diet as compared with the control. In conclusion, ZnONP application up to 80 mg/kg in the diet is safe for broiler chickens and could improve their antioxidant defense and cellular immunity.

Dietary zinc and growth, carcass characteristics, immune responses, and serum biochemistry of broilers

Context Zinc (Zn) is an essential trace element, and plays an important role in growth, bone formation, feathering and appetite of broilers. Accurate supplementation of this mineral is the aim of the animal husbandry. Thus, it is crucial to optimise the Zn concentration in the diet of broilers. Aims The present study was performed to investigate the effects of dietary supplementation of Zn on the growth performance, carcass characteristics, immune responses and serum biochemistry of broilers. Methods A total of 180 1-day-old male broilers (Arbor Acres) were randomly allotted by bodyweight to one of five treatments with six replicates of six birds each. The birds were fed a Zn-unsupplemented corn–soybean meal basal diet (27.75 or 26.88 mg/kg Zn by analysis) or one of the four Zn-supplemented diets, which were the basal diet supplemented with 40, 80, 120, or 160 mg Zn /kg as Zn sulfate (reagent grade ZnSO4•7H2O), for 42 days. Key results No differences were detected on growth performance or carcass characteristics among treatment groups. However, the total protein concentration and albumin concentration tended (P = 0.09) to increase with an increasing concentration of dietary Zn. The antibody titer of Newcastle disease (ND), and alkaline phosphatase (ALP) in serum on Day 21 were significantly increased (P &lt; 0.05) as the Zn supplementation increased in broiler diets. Conclusions These results indicated that dietary Zn supplementation improves the serum antibody titer of ND and ALP activity of broilers, and 86 mg Zn/kg was appropriate for broilers when fed a corn–soybean meal diet in the early stage. Implications The present results have provided scientific basis for broiler production, and accurate supplementation of Zn would effectively improve the growth performance and reduce production costs.

Organic trace minerals improve eggshell quality by improving the eggshell ultrastructure of laying hens during the late laying period

The objective of this study was to investigate the effects of low inclusion levels of organic trace minerals (iron, copper, manganese, and zinc) on performance, eggshell quality, serum hormone levels, and enzyme activities of laying hens during the late laying period. A total of 405 healthy hens (HY-Line White, 50-week-old) were randomly divided into 3 treatments, with 9 replications per treatment and 15 birds per replication. The dietary treatments included a basal diet supplemented with inorganic trace minerals at commercial levels (CON), a basal diet supplemented with inorganic trace minerals at 1/3 commercial levels (ITM), and a basal diet supplemented with proteinated trace minerals at 1/3 commercial levels (TRT). The trial lasted 56 D (8 wk). Compared with the CON group, the ITM group showed decrease in (P < 0.05) egg production, eggshell strength, eggshell palisade layer, palisade layer ratio, serum estrogen, luteinizing hormone, glycosaminoglycan concentration, and carbonic anhydrase activity and increase in (P < 0.05) egg loss and mammillary layer ratio. However, the TRT group almost kept all the indices close to the CON group (P > 0.05). Furthermore, hens fed with low inclusion levels of organic trace minerals had smaller mammillary knobs (P < 0.05) than those in the CON and ITM groups. In conclusion, hens fed with low inclusion levels of proteinated trace minerals had better performance and eggshell strength than those fed with identical levels of inorganic compounds; organic trace minerals improved eggshell quality by improving the eggshell ultrastructure of laying hens during the late laying period.

Estimation of dietary zinc requirement for laying duck breeders: effects on productive and reproductive performance, egg quality, tibial characteristics, plasma biochemical and antioxidant indices, and zinc deposition

This study evaluated the effects of different dietary zinc (Zn) levels on productive and reproductive performance, egg quality, tibial characteristics, plasma biochemical and antioxidant indices, and zinc deposition in laying duck breeders. A total of 504 Longyan duck breeders aged 21 wk were randomly allocated to 6 treatments and fed a basal diet (Zn, 27.7 mg/kg) or that basal diet supplemented with Zn (as ZnSO₄·H₂ O) at 10, 20, 40, 80, or 160 mg Zn per kg of feed for 20 wk. Each group had 6 replicates of 14 ducks each. Dietary Zn supplementation affected (P < 0.05) the egg production, FCR, and shell thickness of laying duck breeders from 21 to 40 wk, and there was a quadratic (P < 0.05) effect between them. Dietary Zn supplementation affected (P < 0.05) and quadratically (P < 0.001) increased the breaking strength, density, and dry defatted weight of tibias. Alkaline phosphatase, calcium, phosphorus, total superoxide dismutase, glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) activities or content in plasma were affected (P < 0.05), and quadratically (P < 0.01) changed by dietary Zn levels. Dietary Zn supplementation affected (P < 0.01) and increased the Zn deposition in egg yolk (linear, P < 0.05; quadratic, P < 0.001) and tibia (linear, P < 0.05). The dietary Zn requirements, in mg/kg for a basal diet containing 27.7 mg/kg Zn, for Longyan duck breeders from 21 to 40 wk of age were estimated to be 65.4 for optimizing egg production, 68.6 for FCR, 102 for hatchling BW, 94.7 for eggshell thickness, 77.2 for tibial breaking strength, 81.4 for tibial density, 78.9 for tibial dry defatted weight, 69.5 for plasma GSH-Px activity, 72.4 for plasma MDA content, and 94.6 for Zn content in tibia. Overall, dietary Zn supplementation, up to 160 mg/kg feed, affected the productive performance, eggshell thickness, tibial characteristics, plasma antioxidant status, and Zn deposition of layer duck breeders. Supplementing this basal diet (27.7 mg/kg Zn) with 70 to 80 mg/kg additional Zn was adequate for laying duck breeders during the laying period.

The Role of Zinc in Poultry Breeder and Hen Nutrition: an Update

Zinc (Zn) is an essential trace mineral in breeder hen diets and functions in diverse physiological processes, including reproduction, immunity, antioxidant ability, and epigenetic processes. In this paper, five main aspects of Zn nutrition in poultry breeder birds and hens, including semen quality, molting, egg production and egg quality, hatchability and embryonic development, and offspring performance, are reviewed. Zn deficiency in poultry breeder birds led to lower semen quality (reducing around 10% sperm motility) and egg production (lowering 3-10 g/day/bird egg mass) as well as poor offspring development and growth performance (increasing 9-10% weak chick ratio and 10% mortality of progeny). Adequate maternal or higher Zn supplementation was adopted not only to induce molting with a greater postmolt performance (rising 4-7% laying rate) but also to enhance progeny immune response and antioxidant ability via epigenetic mechanisms. Therefore, it is necessary to reevaluate the optimal Zn requirement for egg production as well as the embryonic development and offspring chick performance of breeder hens. In the last 10 years, greater attention has been focused on the effectiveness of organic Zn for improving the reproductive performance of breeders and progeny viability and immune status. In fact, organic Zn sources are not always beneficial to the above aspects. So far, it has been very important to know the exact mechanisms of greater bioavailability and the epigenetic role of organic Zn sources in the augmentation of immune status and antioxidant abilities in poultry breeder birds and offspring. Therefore, a comprehensive analysis of these key points will not only aid in maintaining the beneficial effects of Zn nutrition for breeders and their progeny under stable conditions but will also support birds under stressful conditions such as disease as well as provide a better understanding of the integrated nutrition of breeder-offspring.

Accumulation of trace elements in feathers of the Kentish plover Charadrius alexandrinus

A non-invasive study of trace element accumulation in tail feathers of the Kentish plover (Charadrius alexandrinus) was performed along the coastline of the northern littoral strip of the Venice Lagoon, with the aim to verify whether contamination may be a factor affecting conservation status of Kentish plover populations. Body burdens in feathers of 11 trace elements including toxic metals/metalloids and essential elements (As, Cd, Co, Cr, Cu, Hg, Ni, Pb, Se, V, Zn) were quantified by ICP-MS, then concentrations were normalized to feather's age calculated using ptilochronology in order to obtain daily deposition rates. Mercury emerged as a major threat to the conservation of the species, since average feather concentration was clearly above the adverse-effect threshold associated with impairment in the reproductive success in a number of bird species. Also Cd and Se occurred at levels that may impact on the conservation status of the studied species at local scale, even if to a lesser extent than Hg. Gender-related differences in trace element accumulation emerged only for As, although for this element the risks associated to environmental exposure seem to be negligible.

Organic trace minerals on productive performance, egg quality and immune response in Bovans White laying hens

This study was performed in 360 laying Bovans White hens and aimed to evaluate the effect of Carbo-Amino-Phosphate-Chelates (CAFQ) as a mineral premix and its 30% reduction by compared to inorganic trace minerals (ITM) concerning its performance, egg quality, tibia breaking strength and immunity. Sixty-week-old hens were assigned into three treatments with 10 replicates of 12 birds each. Treatments were as follows: (a) (100% ITM), (b) (100% CAFQ) and (c) (70% CAFQ). Based on the results obtained during 12 weeks, under the current test conditions, improved yolk colour (p < 0.05); shell breaking strength (p < 0.05); and storage time (p < 0.05) were observed in hens fed with a diet reduced by 70% in CAFQ inclusion showed similar performance behaviour and better egg breaking strength regarding with ITM, suggesting the possibility of minimizing the inclusion of trace minerals in laying hen diets improving environmental impact, in contrast to the use of inorganic sources of minerals.

Optimization of Dietary Zinc Requirement for Broiler Breeder Hens of Chinese Yellow-Feathered Chicken

Simple Summary

China is the second-largest global producer of chicken meat, almost half of which is from the Chinese yellow-feathered breed; a systematic program has been initiated to improve its feeding standards. This study evaluated the optimal requirement of dietary zinc for maximal egg production, egg quality, tibial quality, and antioxidant indices of laying broiler breeders. The results revealed several beneficial effects of supplementary zinc on egg production, feed conversion ratio, yolk zinc content, tibial quality and the antioxidant indices in the serum, liver and ovary. The optimal zinc requirement was estimated based on a regression model.

Abstract

This study aimed to establish the optimal dietary zinc requirement of Chinese yellow-feathered Lingnan broiler breeders. A total of 576 breeder hens aged 58 weeks were randomly assigned to six treatments, each with 6 replicates of 16 birds (n = 96/treatment). The hens were fed either a basal diet (22.81 mg/kg Zn) or the same basal diet supplemented with additional 24, 48, 72, 96, and 120 mg Zn/kg up to 65 weeks of age. Compared to the results of birds fed the basal diet (22.81 mg Zn/kg), the dietary supplementation with additional Zn (mg/kg) showed higher egg laying rate (at 48–120 mg), EM (at 96 mg/kg), yolk Zn content (at 24–120 mg/kg), fertility (at 48–120 mg/kg), hatchability (at 48–96 mg/kg), tibial breaking strength (at 24–48 mg/kg), tibial ash content (at 48 mg/kg), serum CuZnSOD activity (at 72 mg/kg) and T-AOC (at 48 mg/kg), and ovarian CuZnSOD and GSH-Px activities (at 96–120 mg/kg), and lower FCR (at 96 mg/kg). The regression model showed that the optimal supplemental Zn for maximal egg laying rate, yolk Zn content, fertility, and hatchability of Chinese yellow-feathered broiler breeders aged 58 to 65 weeks were 71.09, 92.34, 94.44 and 98.65 mg/kg diet, respectively.

Low-dose of organic trace minerals reduced fecal mineral excretion without compromising performance of laying hens

OBJECTIVE

The objective of this study was to investigate the effects of low doses of organic trace minerals (iron, copper, manganese, and zinc) on productive performance, egg quality, yolk and tissue mineral retention, and fecal mineral excretion of laying hens during the late laying period.

METHODS

A total of 405 healthy hens (HY-Line White, 50-week-old) were randomly divided into 3 treatments, with 9 replicates per treatment and 15 birds per replicate. The dietary treatments included feeding a basal diet + inorganic trace minerals at commercial levels (CON), a basal diet + inorganic trace minerals at 1/3 commercial levels (ITM), and a basal diet + proteinated trace minerals at 1/3 commercial levels (TRT). The trial lasted for 56 days.

RESULTS

Compared to CON, ITM decreased (p<0.05) egg production, daily egg mass, albumen height, eggshell strength, yolk Fe concentration, serum alkaline phosphatase activity and total protein, and increased (p<0.05) egg loss and feed to egg ratio. Whereas with productive performance, egg quality, yolk mineral retention, and serum indices there were no differences (p>0.05) between CON and TRT. The concentrations of Fe and Mn in the tissue and tibia were changed notably in ITM relative to CON and TRT. Both ITM and TRT reduced (p<0.05) fecal mineral excretion compared to CON.

CONCLUSION

These results indicate that dietary supplementation of low-dose organic trace minerals reduced fecal mineral excretion without negatively impacting hen performance and egg quality.

The Influence of the Partial Replacing of Inorganic Salts of Calcium, Zinc, Iron, and Copper with Amino Acid Complexes on Bone Development in Male Pheasants from Aviary Breeding

Simple Summary

A significant problem of birds reared in farms and then reintroduced to natural living environment is their survival, which is usually much lower than that of the free-living ones. Behavioral and physiological deficiencies rather than morphological anatomy decide about failure, nevertheless, the birds’ body condition, including quality and maturity of skeletal system, are also important. In this context, the problem of proper nutrition for growing game birds is a major one. The level and source of microelements, as well as the source of protein are the main factors affecting bone growth in young captive-reared birds. Since calcium, zinc, iron, and copper are critical nutrients in all practical diets, this experiment was undertaken to determine the possibility of the partial inclusion of organic forms of these elements to the diet of pheasants in order to improve their bone development and survival.

Abstract

This study analyzed the effects of partial replacing of Ca, Fe, Zn, and Cu salts with glycine chelates on the measures of bones health in 16-week-old captive-reared male pheasants, allocated to one of the three experimental groups supplemented with Ca, Fe, Zn, and Cu in forms of inorganic salts (the control group) or groups receiving from the ninth week 25% and 50% of supplemented elements as glycine chelates. At the end of rearing birds receiving chelates were heavier (p < 0.001) and their tibia showed an increase of numerous mechanical parameters: yield and ultimate force (p = 0.028, p < 0.001, respectively), stiffness (p = 0.007), Young modulus (p < 0.001), compared to the control animals. The bones of birds receiving chelates in 50% were also heavier (p < 0.001) and longer (p = 0.014), with thinner cortical bone in midshaft (p = 0.027) and thicker proximal trabeculae (p < 0.001) compared to the control. While both doses of chelates increased mineral density in midshaft (p = 0.040), bone content of Cu and Zn decreased (p = 0.025, p < 0.001, respectively). The content of immature collagen in cancellous bone and articular cartilage increased in groups receiving chelates (p < 0.001, p = 0.001, respectively). In conclusion, glycine chelates probably enhanced development of the skeletal system in male pheasants as bones were denser and more resistant to mechanical damage.

Effect of dietary zinc pectin oligosaccharides chelate on growth performance, enzyme activities, Zn accumulation, metallothionein concentration, and gene expression of Zn transporters in broiler chickens1

This study was to investigate the effect of zinc pectin oligosaccharides chelate (Zn-POS) on growth performance, serum enzyme activities, tissue zinc accumulation, metallothionein (MT) concentrations, and gene expression of zinc transporters (ZnT) in broilers. Five hundred forty 1-d-old Arbor Acres broiler chicks were randomly assigned to 5 dietary groups with 6 replicates of 18 birds per replicate. The diets were formulated with the same supplemental Zn level (80 mg/kg diet) but different amount of the Zn-POS: 0, 200, 400, 600, and 800 mg Zn-POS/kg diet. ZnSO4 was used to adjust to the desired amount of the Zn (80 mg/kg) in the Zn-POS diets. Broilers were fed with the experimental diets for 42 d including the starter (days 1 to 21) and grower (days 22 to 42) phases. Our results showed that dietary supplementation of Zn-POS linearly and quadratically increased (P < 0.05) the average daily gain and gain-to-feed ratio during 22 to 42 d and 1 to 42 d as well as body weight on day 42, whereas reduced (P < 0.05) the sum of mortality and lag abnormalities in broilers on day 42. Besides, serum alkaline phosphatase and copper-zinc superoxide dismutase activities increased (P < 0.05) linearly and quadratically in response to dietary Zn-POS supplemental level on day 42. Dietary Zn-POS supplementation increased Zn accumulation in serum (linear, P < 0.05), liver (linear, P < 0.05), and pancreas (linear and quadratic, P < 0.05). In addition, Zn-POS supplementation linearly and quadratically increased (P < 0.01, P < 0.05, respectively) MT concentrations in liver and pancreas of broilers. Pancreatic mRNA levels of MT, ZnT-1, and ZnT-2 increased (P < 0.05) linearly and quadratically, and the mRNA expression of metal response element-binding transcription factor-1 increased linearly (P < 0.05), in response to dietary Zn-POS supplementation. In conclusion, supplementation of Zn-POS in the diet increases Zn enrichment in the metabolic organs such as liver and pancreas and promotes productive performance in broilers.