Zinc Amino Acid Complex Research Articles

Organic Zn and nano-Zn amino acids chelates modulate quality growth attributes and antioxidants activity for biofortified apple (Malus x domestica Borkh.) production

Zinc biofortification increase nutritional content of crops to combat Zn deficiency in human diets. Foliar Zn bio-organics can significantly improve Zn content of fruit crops. This method is efficient, can be tailored to specific crop needs, and is crucial for enhancing the nutritional quality of food crops, contributing to better human health outcomes. In order to evaluate the efficacy of foliar sprays in promoting plant growth and development, the study evaluated the comparative efficacy of zinc amino acid complexes with zinc sulphate in apple (Malus × domestica Borkh.) cv. Gala Schniga Schnico during the years 2022 and 2023. Different Zn nutrient sources namely, Zn glycinate (Zn-Gly), Zn gluconate (Zn-Glu), Zn amino acid chelate (Zn-AAC), nano Zn amino acid chelate (NZn-AAC) were applied at the rate of 200 and 400 mg/L each and conventional ZnSO4 at 1250 mg/L with three replicates. Foliar application of the Zn nutrient sources was executed at four stages i.e., 15 days before petal fall, petal fall, 15 days after petal fall, and after harvest. The results revealed that NZn-AAC at 400 mg kg-1 registered the maximum increase in vegetative growth and flowering traits. The superior treatment also exhibited highest fruit set (62.90 %) and fruit yield (5.62 kg/tree) in apple. Fruit quality parameters, in terms of TSS, total sugars, ascorbic acid and anthocyanin contents were increased by 22.9, 17.8, 50.2, and 16.6 per cent, respectively through superior treatment. Fruit flesh and peel nutrient content in terms of P, K, Ca, Mg and Zn also showed improvement through NZn-AAC400 compared to control. Maximum decrease in phytic acid (1.09 %) and increase in ursolic acid (273.95 µg/mL) were also reported with NZn-AAC400. The differences between Zn nutrient sources were analysed using PCA, which explained 95.70 per cent (PC1), 97.81 per cent (PC2), 99.11 per cent (PC3), 99.42 per cent (PC4) and 99.63 per cent (PC5) of the cumulative variance based on Eigen value (>1). In accordance with the results, Zn amino acid complexes emerged as beneficial environment-friendly Zn source for improving growth, fruit yield, quality with higher Zn bio-availability compared to ZnSO4.

201 The effects of the supplementation of a Zinc-amino acid complex in pig nursery diets with differing pharmacological levels of zinc oxide and complexity

Abstract Diet complexity (DC), which has significance in nursery pig production, generally refers to a greater number of highly digestible ingredients. Increased DC may have even greater significance in scenarios of reduction or withdrawal of zinc oxide (ZnO) in nursery diets. The objectives were to determine 1) the impact of adding Zn-amino acid complex (Zinpro ProPath Zn) to mid- (MC) and low-complexity (LC) diets on nursery pig performance and health compared with a high complexity (HC) diet, and 2) the impact of Zinpro ProPath Zn in diets with and without pharmacologic levels of ZnO. A total of 2,400 mixed-sex weanling pigs [initial body (BW) weight = 5.79 ± 0.15 kg] were assigned to 1 of 5 dietary treatments during nursery (42 d) as follows: 1) HC; MC diet with 2) MC+ZnO) or without 3) MC-ZnO) pharmacologic ZnO; and LC diet with 4) LC+ZnO) or without 5) LC-ZnO) pharmacologic ZnO. All diets except HC were supplemented with Zinpro ProPath Zn (125 mg/kg Zn) and ZnO [3,000, 2,000, and 0 mg/kg Zn during Phases I (14 d), II (14 d) and III (14 d), respectively]. Different DC were achieved by manipulating the inclusion of spray-dried plasma, soy protein concentrate, and whey protein. Growth performance, onset of feed intake, fecal dry matter, number of injectable treatments administered, and serum acute-phase response were assessed. Pigs fed HC (20.0 kg) had greater final BW (FBW) compared with pigs fed MC-ZnO (18.8 kg), which had greater FBW compared with pigs fed LC-ZnO (17.5 kg; SEM = 0.34; P < 0.05). Average daily feed intake (ADFI) was greater in pigs fed HC (0.46 kg/d) compared with MC-ZnO (0.43 kg/d) and LC+ZnO (0.42 kg/d), which had greater ADFI compared with LC-ZnO (0.39 kg/d; SEM = 0.01; P < 0.05). Similarly, average daily gain (ADG) and gain to feed ratio (G:F) were greater in pigs fed HC (0.33 kg/d, 0.72 kg/kg, respectively) compared with pigs fed LC (0.27 kg/d, 0.67 kg/kg, respectively), regardless of ZnO (SEM = 0.01; P < 0.05). There was no effect of dietary treatments on the fecal dry matter or on the onset of feed intake of pigs (P > 0.10). The number of injectable treatments administered was greatest in LC-ZnO (62.7%), followed by LC+ZnO (50.6%), MC regardless of ZnO (44.0%), and HC (36.7%; SEM = 1.04; P < 0.05). Serum alkaline phosphatase was less in LC-ZnO than the other groups (229.8 vs. 280.9 ± 11.9 IU/L; P < 0.05). Taken together, feeding HC diets during the nursery appears to be effective in improving performance and health of pigs, particularly when compared with MC and LC diets without ZnO. Moreover, the addition of Zinpro ProPath Zn may partially attenuate the negative effects of ZnO removal in MC, but not LC, diets.

Effects of zinc supplementation from organic and inorganic sources on growth, blood biochemical indices, and intestinal microarchitecture in broilers

In poultry nutrition, zinc supplementation is typically achieved through the addition of zinc oxide or zinc sulfate to the feed. The alternative approach of organic sources utilizes an organic ligand to bind zinc (Zn), resulting in higher bioavailability. Thus, a study was conducted to assess and compare the impact of a methionine-complexed Zn versus an inorganic Zn on growth, blood biochemical profile, gut histomorphology, and fecal excretion of Zn in broilers. The experimental design included two treatments: the addition of a zinc amino acid complex or zinc oxide to the basal diet. The zinc amino acid complex was supplemented at a dose equivalent to the inorganic zinc (Zn-80), while the organic zinc was provided at levels of 20, 40, and 80 mg/kg to a total of 400 broilers. There were five treatments in total, and each treatment was replicated four times. Broilers supplemented with an organic form of Zn at the level of 80 mg/kg had significantly (p < 0.05) higher body weight gain and lower feed conversion ratio (F/G). Significantly (p < 0.05) higher Zn excretion was recorded in broilers supplemented with inorganic Zn supplementation. Significantly (p < 0.05) higher villus length and width, their ratio, and lower (p < 0.05) crypt depth were observed in birds supplemented with 80 mg/kg organic Zn. From the results of the present study, it was concluded that Zn from an organic source at the rate of 80 mg/kg was superior in terms of growth performance, intestinal histomorphology and less excretion of Zn to the environment in broilers.

Evaluating the effect of optimal zinc amino-acid complex supplementation in laying pullets on performance and zinc retention.

This study investigated the optimal dietary intake of zinc amino acid complex (Zn-AAC) for white-layer pullets, focusing on their productive performance, biochemical profile, organ biometry, and body zinc retention. The study involved 360 Dekalb White pullets (average weight: 433 ± 4.42 g) aged from 6 to 16 weeks and distributed into 6 treatments with 6 replications each. The Zn-AAC inclusion levels ranged from 5 to 75 mg kg-1. Zinc intake was modeled using a nonlinear equation, Y = ∝ *1- e-βX, where α is the maximum response, β is the rate at which the response approaches the maximum (P < 0.05). The Zn-AAC supplementation had significant effects on average daily gain (ADG), average daily feed intake (ADFI), and feed convention ratio (FCR) (P < 0.01). Optimal intake levels of Zn-AAC were estimated at 0.234, 0.340, and 0.315 mg bird-1 day-1 (5.42, 7.87, and 7.30 mg kg-1) for ADG, ADFI, and FCR, respectively. The Zn-AAC supplementation affected the Zn body retention in pullets (P < 0.01), with an optimal ingestion at 1.86 mg bird -1 day-1, corresponding to a dietary supplementation of 43.10 mg kg-1. Additionally, supplementation affected alkaline phosphatase (ALP) activity (P < 0.01) without significant changes in aspartate aminotransferase, albumin, and globulin levels. The optimal Zn-AAC intake level for ALP activity was 1.45 mg bird -1 day-1, corresponding to dietary supplementation of 33.60 mg kg-1. Based on Zn body retention, we recommend up to 1.86 mg bird -1 day-1 of Zn-AAC, which is equivalent to 43.10 mg kg-1.

Optimal density-functional theory method for zinc-amino acid complexes determined by analyzing structural and Fourier-transform infrared spectroscopy data.

Metal-amino acid complexes are important compounds for the human body. Their nutritional value and anticancer, antibacterial, and catalytic properties are the focus of several studies. Density functional theory (DFT) can be used to predict their properties by optimizing their structures and performing electron population analyses. However, conventional computational methods cannot adequately determine the parameters of polymeric metal-amino acid complexes. Therefore, intermolecular interactions of polymers must be considered to correctly predict the properties of metal-amino acid and related metal complexes. In this study, different DFT protocols were used to acquire the infrared spectra and determine interatomic distances of two zinc-amino acid complexes, Zn(Gly)2 and Zn(Met)2. The results were compared to spectroscopic and X-ray crystallographic data, revealing that the M06 and M06-L functionals and the 6-311++G(d,p) basis set produced the smallest computational errors. Our results provide a foundation for future theoretical studies on other metal-amino acid and metal-organic complexes.

Responses to graded levels of zinc amino acid complex in Nile tilapia (Oreochromis niloticus).

Zinc (Zn) is an essential micronutrient that plays a crucial role in fish development and physiology. This study aimed to evaluate the effects on growth and health in Nile tilapia (Oreochromis niloticus) supplemented with graded levels of zinc amino acid complex (Zn-AA) and subjected to transport stress. Nile tilapia (21.78 ± 0.17g; (n = 12 fish per tank; stocking density of 1.045kg- 3) were fed with 0, 25, 50, 75, or 100mg Zn-AA kg- 1 (equivalent to 77.49, 102.69, 127.89, 153.09, or 178.29mg Zn kg- 1) in extruded diets (280g kg- 1 digestible protein; isoproteic and isocaloric) for 60 days. At the end of the experimental period, after growth performance measurements, the fish were transported by car for 3h, and blood collection was performed. The linear regression showed that the best growth performance (final weight, final biomass, weight gain, specific growth rate, and feed intake) was found in fish fed with 100mg Zn-AA kg diet- 1 (p < 0.05). The increased dietary Zn-AA increased linearly plasma triglyceride levels, hemoglobin, mean corpuscular hemoglobin, and leukocyte values and reduced plasma total protein, cholesterol (total and LDL), and aspartate aminotransferase levels (p < 0.05). According to quadratic regression, the highest plasma glucose and alanine aminotransferase values were found in the control group (p < 0.05). In conclusion, under the conditions of this study, 100mg Zn-AA kg diet- 1 is recommended for Nile tilapia as it can improve their growth, metabolism, physiology, and immunity.

Facile Synthesis of N-Doped Metal-Free Catalysts for Oxygen Reduction Reaction via a Self-Sacrificed Template Method Using Zinc Amino-Acid Complex

Facile Synthesis of N-Doped Metal-Free Catalysts for Oxygen Reduction Reaction via a Self-Sacrificed Template Method Using Zinc Amino-Acid Complex

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 120mgkg-1 Zn as ZnSO4, 30, 60, 90 or 120mgkg-1 Zn as ZnN, or 30mgkg-1 Zn as ZnA separately). Each group had six replicates, with 12 birds per replicate. The results showed that the addition of 60mgkg-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 30mgkg-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.

Effects of Zinc Status on Expression of Zinc Transporters, Redox-Related Enzymes and Insulin-like Growth Factor in Asian Sea Bass Cells.

Since Asian sea bass is one of the economically most important fish, aquaculture conditions are constantly optimized. Evidence from feeding studies combined with the current understanding of the importance of zinc for growth and immune defense suggest that zinc supplementation may be a possible approach to optimize aquacultures of Asian sea bass. To investigate the effects of zinc deficiency and zinc supplementation, cells from Asian sea bass were incubated in culture medium with different zinc contents. The expression of genes, important for zinc homeostasis, redox metabolism, and growth hormones was analyzed using RT-PCR. Zinc deficiency induced the expression of certain zinc transporters (ZIP14, ZIP10, ZIP6, ZIP4, ZnT4, ZnT9) as well as of SOD1, IGF I and IGF II, while expression of ZnT1 and metallothionein (MT) was reduced. Zinc supplementation decreased the expression of ZIP10, while expression of ZnT1 and MT were elevated. No differences in the effects of zinc supplementation with zinc sulfate compared to supplementation with zinc amino acid complexes were observed. Thus, extracellular zinc conditions may govern the cellular zinc homeostasis, the redox metabolism and growth hormone expression in cells from Asian sea bass as reported for other fish species. Our data indicate that supplementing aquacultures with zinc may be recommended to avoid detriments of zinc deficiency.

Effects of the dietary zinc source and vitamin E level on live weight and carcass yield and meat quality in male broilers reared under chronic cyclic heat stress conditions in the finisher phase.

The objective of this study was to evaluate the effect of the interaction of the zinc source (ZnSO4 vs. zinc amino acid complex) and vitamin E level (50 IU/kg vs. 100 IU/kg) on meat yield and quality in broilers subjected to chronic cyclic heat stress in the finisher phase. A total of 1224 one-day-old male Ross 308 broilers were randomly distributed among four dietary treatments. Each treatment contained nine replicates of 34 birds, housed in floor pens in a temperature- and lighting-controlled room. Treatments were organized in a 2 × 2 factorial arrangement: two sources of zinc, 60 mg/kg of Zn as ZnSO4 or 60 mg/kg of Zn as zinc amino acid complexes (ZnAA), combined with two levels of vitamin E (50 or 100 IU/kg). From day 28 until day 37 (finisher phase), all birds were subjected to chronic cyclic heat stress (32 ± 2°C for 6 h daily). In the present study, it was observed that replacing ZnSO4 with ZnAA increased breast meat weight and yield of broilers reared under chronic cyclic heat stress conditions, whereas total slaughter yield was not affected. Moreover, it was observed that replacing ZnSO4 with ZnAA resulted in breast meat with a lower drip and thawing loss and a higher marinade uptake. In conclusion, replacing ZnSO4 with more readily available ZnAA can improve breast meat yield and increase the water-holding capacity of breast meat of broilers exposed to chronic cyclic heat stress at the end of the production cycle. However, as no thermoneutral group was included in the present study, the observed effects of the zinc source cannot be generalized as a solution for heat stress. Moreover, the beneficial effects of ZnAA on breast meat yield and quality seem to be independent of the vitamin E level, and increasing vitamin E level has no additional beneficial effects.

PSIV-B-19 Determining the Effect of Zinc Status on eye Health and its Relationship with Infectious Bovine Keratoconjunctivitis in Beef Calves

Abstract Crossbred beef calves (n = 30) were stratified by gender and BW and placed into 1 of 16 dry lot pens. Pens were allocated to either: 1) the control treatment (CON) with calves fed a basal ration containing 31 mg of zinc/kg DM; or 2) Zn supplemented treatment (SUP) with calves fed the basal ration supplemented with 30 mg of zinc/kg DM (provided as zinc amino acid complex). Growth performance was recorded every 28-d during the 143-d study. On d 115, cattle were given a commercial vaccine containing M. bovis and M. bovoculi bacterins. Blood samples were collected and analyzed for serum zinc, alkaline phosphatase activity (ALP, 28-d intervals), and vitamin A (d 0 and 143). Samples for serum and tear IgG concentrations specific for M. bovis and M. bovoculi were taken on d 115, 129, and 143. Data were analyzed as repeated measures, where appropriate, using the MIXED procedure of SAS. Dietary zinc status did not impact liver or zinc concentrations (P ≥ 0.36), BW (P ≥ 0.66) or ADG (P ≥ 0.14). There was no effect of treatment (P ≥ 0.16) or treatment by time interaction (P &amp;gt; 0.39) on tear IgG specific for either M. bovis or M. bovoculi. However, serum IgG concentrations specific for M. bovis were greater (P = 0.02) in CON calves compared with SUP calves, and serum IgG concentrations specific for M. bovoculi tended (treatment by time, P = 0.08) to increase more in CON calves. Both serum and tear IgG concentrations specific for either bacterin increased (day effect, P &amp;lt; 0.001) from d 115 to 143. Results did not support a relationship between dietary Zn and eye health in cattle. However, this could be explained by the similarity in liver and serum zinc concentrations.

Effects of Chromium-L-Methionine in Combination with a Zinc Amino Acid Complex or Selenomethionine on Growth Performance, Intestinal Morphology, and Antioxidative Enzymes in Red Tilapia Oreochromis spp.

Simple SummaryThe purpose of this study was to develop diet optimization for the growth and health of fish under intensive aquaculture systems, with a focus on the farming of Nile tilapia and red tilapia in Thailand. Diets and proper nutrition are more important than ever in raising healthy, antibiotic-free fish. Organic trace minerals have been used to promote the growth and health status of fish in aquafeeds. In this investigation, we studied the effects of chromium-L-methionine, in combination with a zinc amino acid complexor in combination with selenomethionine, on the growth performance, feed utilization, and immune responses of red tilapia. The results for the combination of chromium-L-methionine with a zinc amino acid complex showed beneficial effects for red tilapia in terms of growth performance, feed utilization, and intestinal morphology. The results for the combination of chromium-L-methionine with selenomethionine demonstrated that the levels of antioxidative enzymes, especially glutathione, could be increased to provide an innate immune response in red tilapia.To consider diet optimization for the growth and health of fish under intensive aquaculture systems, with a focus on the farming of Nile tilapia and red tilapia in Thailand, we conducted an experiment based on a completely randomized design (CRD), with three treatments and four replicates. Three diets, supplemented with different trace minerals, were applied to selected groups of fish: (a) a control diet, without organic trace minerals supplementation; (b) a T1 diet of chromium-L-methionine at 500 ppb, in combination with a zinc amino acid complex at 60 parts per million (ppm); and (c) a T2 diet of chromium-L-methionine at 500 ppb in combination with selenomethionine at 300 ppb. Red tilapia with an initial mean weight of 190 ± 12 g/fish were randomly distributed into cages of 2 × 2 × 2.5 m in a freshwater pond (12 cages in total), with 34 fish per cage and a density of 17 fish/m3. During the 8 week feeding trial, the fish were fed 3–4% of their body weight twice a day. The fish were weighed, then blood samples were collected to study their immune responses. The intestines were collected, measured, and analyzed at the end of the feeding trial. The results showed that the red tilapia that were fed with diets of chromium-L-methionine in combination with a zinc amino acid complex in the T1 treatment had significantly (p < 0.05) higher final weights, weight gains, average daily gains (ADGs), and better feed conversion ratios (FCRs), compared with fish that were fed with the control diet without organic trace minerals and with fish that were fed with the T2 diet (p < 0.05). The midgut and hindgut villus heights of the group fed with chromium-L-methionine in combination with a zinc amino acid complex in the T1 treatment were significantly higher than those of the other groups (p < 0.05). The levels of the antioxidative enzyme superoxide dismutase (SOD) and lysozyme activity were not significantly different from those of fish that were fed with the control diet (p > 0.05), whereas the glutathione level tended to increase (p < 0.1) in fish that were fed with chromium-L-methionine in combination with selenomethionine in the T2 treatment. Therefore, we concluded that chromium-L-methionine in combination with a zinc amino acid complex or selenomethionine clearly enhanced red tilapia’s growth performance and feed utilization through the promotion of antioxidative enzyme activity and immune response.

Effect of chelated source of additional zinc and selenium on performance, yolk fatty acid composition, and oxidative stability in laying hens fed with oxidised oil

ABSTRACT 1. The following study determined whether the effects of the combined addition of zinc amino acid complex (ZA) and selenomethionine (SM) was superior to their single addition in controlling the oxidative stress induced by dietary oxidised fat in laying hens. 2. Two hundred and forty 32-week-old laying hens were divided into the following dietary treatments (each consisting of six replicates of eight birds): 1) a fresh soy oil (FSO) diet; 2) an oxidised soy oil (OSO) diet; 3) an OSO diet plus 20 mg zinc as ZA/kg (OSO+ZA); 4) an OSO diet plus 0.2 mg selenium as SM/kg (OSO+SM); and 5) an OSO diet plus ZA and SM (OSO+ZA+SM). 3. After 10 weeks of feeding hens, feed intake, egg production, and egg mass in the OSO+ZA+SM group were similar to the FSO group but better (P < 0.05) than those in the OSO group. Shell thickness and shell breaking strength were significantly improved by the OSO+ZA and OSO+ZA+SM treatments. 4. Increases in the yolk concentrations of palmitic acid and total saturated fatty acids (SFA), and decreases in yolk linoleic acid, n-6 polyunsaturated fatty acids (PUFA), total PUFA, and PUFA/SFA ratio were induced by dietary oxidised fat which were normalised (P < 0.05) by OSO+SM and OSO+ZA+SM. 5. An increase (P < 0.05) in malondialdehyde and a decrease in 2,2-diphenyl-picrylhydrazyl radical scavenging activity in the yolk, induced by dietary oxidised fat, was significantly improved by all dietary supplementations, but only birds fed the OSO+ZA+SM diet exhibited similar values to those fed FSO. 6. In conclusion, the simultaneous inclusion of organic zinc plus selenium in the oxidised fat diets was beneficial for improving egg-laying performance, yolk fatty acid profile, and oxidative stability, but not for internal egg quality, compared with either zinc or selenium alone in laying hens.

Zinc(II) Complexes of Amino Acids as New Active Ingredients for Anti-Acne Dermatological Preparations.

Zinc compounds have a number of beneficial properties for the skin, including antimicrobial, sebostatic and demulcent activities. The aim of the study was to develop new anti-acne preparations containing zinc–amino acid complexes as active ingredients. Firstly, the cytotoxicity of the zinc complexes was evaluated against human skin fibroblasts (1BR.3.N cell line) and human epidermal keratinocyte cell lines, and their antimicrobial activity was determined against Cutibacterium acnes. Then, zinc complexes of glycine and histidine were selected to create original gel formulations. The stability (by measuring pH, density and viscosity), microbiological purity (referring to PN-EN ISO standards) and efficacy of the preservative system (according to Ph. Eur. 10 methodology) for the preparations were evaluated. Skin tolerance was determined in a group of 25 healthy volunteers by the patch test. The preparations containing zinc(II) complexes with glycine and histidine as active substances can be topically used in the treatment of acne skin due to their high antibacterial activity against C. acnes and low cytotoxicity for the skin cells. Dermatological recipes have been appropriately composed; no irritation or allergy was observed, and the preparations showed high microbiological purity and physicochemical stability.

Effect of vitamin E level and dietary zinc source on performance and intestinal health parameters in male broilers exposed to a temperature challenge in the finisher period.

The objective of this study was to evaluate the interaction of zinc source (ZnSO4 vs. zinc amino acid complex) and vitamin E level (50IU vs. 100IU) on performance and intestinal health of broilers exposed to a temperature challenge in the finisher period. A total of 1224dayold male Ross 308 broilers were randomly distributed among 4 dietary treatments (9 replicates per treatment). Dietary treatments were organized in a 2×2 factorial arrangement: two sources of zinc, 60mg/kg of Zn as ZnSO4 .7H2 O or 60mg/kg of Zn as zinc amino acid complexes (ZnAA) combined with two levels of vitamin E (50 or 100IU/kg). Zinc and vitamin E were added to a wheat/rye-based diet that was designed to create a mild nutritional challenge. From day 28 until day 36 (finisher period), all birds were subjected to chronic cyclic high temperatures (32°C±2°C and RH 55-65% for 6h daily). The combination of ZnAA and 50IU/kg of vitamin E improved weight gain in the starter (day 0-10), finisher (day 28-36) and overall period (day 0-36) and feed conversion ratio in the starter (day 0-10) and finisher phase (day 28-36). Providing Zn as ZnAA significantly improved villus length and villus/crypt ratio in the starter, grower and finisher period and decreased infiltration of T-lymphocytes and ovotransferrin leakage in the finisher period. In conclusion, providing broilers with a diet supplemented with ZnAA and a vitamin E level of 50IU/kg, resulted in better growth performance as compared to all other dietary treatments. Interestingly, under the conditions of this study, positive effects of ZnAA on performance did not occur when vitamin E was supplemented at 100IU/kg in feed. Moreover, providing zinc as zinc amino acid complex improved intestinal health.

The effects of zinc amino acid complex on biomarkers of gut integrity, inflammation, and metabolism in heat-stressed ruminants

Study objectives were to evaluate the effects of replacing 40 mg/kg of dietary Zn from Zn sulfate (ZS) with Zn amino acid complex (ZA; Zinpro Corporation, Eden Prairie, MN) on inflammation and intestinal integrity in heat-stressed and pair-fed (PF) ruminants. Forty Holstein steers (173.6 ± 4.9 kg) were randomly assigned to 1 of 5 dietary-environmental treatments: (1) thermoneutral (TN) ad libitum with 75 mg/kg of dry matter (DM) ZS (ZSCON); (2) TN pair-fed with 75 mg/kg DM ZS (ZSPF); (3) TN pair-fed with 40 mg/kg DM ZA and 35 mg/kg DM ZS (ZAPF); (4) heat stress (HS) ad libitum with 75 mg/kg DM ZS (ZSHS); and (5) HS ad libitum 40 mg/kg DM ZA and 35 mg/kg DM ZS (ZAHS). Before study initiation, calves were fed their respective diets for 21 d. Following the pre-feeding phase, steers were transferred into environmental chambers and were subjected to 2 successive experimental periods. During period 1 (5 d), all steers were fed their respective diets ad libitum and housed in TN conditions (20.2 ± 1.4°C, 30.4 ± 4.3% relative humidity). During period 2 (6 d), ZSHS and ZAHS steers were exposed to cyclical HS conditions (27.1 ± 1.5°C to 35.0 ± 2.9°C, 19.3 ± 3.5% relative humidity), whereas the ZSCON, ZSPF, and ZAPF steers remained in TN conditions and were fed ad libitum or pair-fed relative to their ZSHS and ZAHS counterparts. Overall, steers exposed to HS had markedly increased rectal temperature (0.83°C), respiration rate (26 breaths per min), and skin temperature (8.00°C) relative to TN treatments. Rectal temperature from ZAHS steers was decreased (0.24°C) on d 4 to 6 of HS relative to ZSHS steers. Regardless of diet, HS decreased DMI (18%) relative to ZSCON steers. Circulating glucose from HS and PF steers decreased (16%) relative to ZSCON steers. Heat stress and nutrient restriction increased circulating nonesterified fatty acids 2- and 3-fold, respectively, compared with ZSCON steers. Serum amyloid A increased ~2-fold in PF relative to ZSCON and HS steers. We detected no treatment effect on blood pH; however, ZAHS steers had increased HCO3 relative to ZSHS. Relative to ZSHS, ZAHS steers had increased jejunum villi height (25%), a tendency for increased ileum villi height (9%), and decreased duodenal villi width (16%). In summary, ZA supplementation has some beneficial effects on thermal indices, intestinal architecture characteristics, and biomarkers of leaky gut in heat-stressed steers, indicative of an ameliorated heat load, and thus may be a nutritional strategy to minimize negative consequences of HS.

Research Note: Effects of organic zinc on broiler intestinal permeability and integrity in Clostridium perfringens–challenged condition

This study evaluates the effects of a zinc–amino acid complex on broiler's intestinal permeability and integrity challenged with Clostridium perfringens. A total of 180 Arbor Acres 1-day-old male broilers were assigned to 6 treatments in a completely randomized 2 × 3 factorial design. The experiment investigated the comparative effects of inorganic and organic zinc supplements, that is (ZnSO4 treatment: 80 mg zinc/kg from ZnSO4; iso-dose replacement group. (ISO) treatment:40 mg zinc/kg from ZnSO4 plus 40 mg zinc/kg from a zinc–amino acid complex; and organic treatment: 40 mg zinc/kg from a zinc–amino acid complex) on C. perfringens–challenged broilers. C. perfringens, on the one hand, compromised intestinal mucosal barrier function by increasing the intestinal permeability of fluorescein isothiocyanate–labeled dextran (P < 0.05) and plasma endotoxin level, on the other hand, decreased both the transepithelial electrical resistance and the relative expression of occludin levels in the ileum at day 21 (P < 0.05). However, zinc supplement alleviates C. perfringens-induced pathologic changes in the intestinal permeability. ISO treatment, in particular, enhanced the villus height–to–crypt depth ratio and transepithelial electrical resistance and also reduced plasma endotoxin levels. In addition, zinc supplement relatively enhanced the expression of occludin levels in the ileum compared with the C. perfringens–challenged group. ISO treatment had the highest relative expression of occludin levels in the ileum. Thereby, the results indicated that partial replacement of ZnSO4 with a zinc–amino acid complex in the broiler diet could promote intestinal mucosal barrier function during C. perfringens infection via increased expression of occludin in the ileum.

Effect of the level and source of supplementary dietary zinc on egg production, quality, and zinc content and on serum antioxidant parameters and zinc concentration in laying hens.

Zinc is vital for proper functioning of an animal. Two sources of zinc are commonly supplemented in animal feed, organic and inorganic zinc, and there are reports that the former is absorbed to a greater extent than the latter. We hypothesized that supplementary zinc would increase zinc content in eggs of laying hens and that organic zinc would be more effective than inorganic zinc. To test these hypotheses, we examined the effect of levels and sources of supplemental dietary zinc on average daily feed intake (ADFI), egg production, and zinc content in eggs and on serum antioxidant capacity and zinc concentration in laying hens. A total of 720 Roman laying hens (21-week-old) were randomly assigned to 5 treatment groups with 6 replicates, with 24 hens in each replicate. Two sources of zinc, organic (zinc amino acid complex) and inorganic (zinc sulfate), each with 2 levels, low (35 mg/kg) and high (70 mg/kg), comprised 4 treatment groups, and a control group without supplementary zinc was the fifth group. Seven days were allowed for adjustment to the conditions, and then measurements were taken over 42 D. There was no difference in ADFI, average egg weight (EW), ADFI-to-EW ratio, and egg quality (P > 0.05) among the 5 treatment groups; supplemental zinc increased serum concentrations of Zn2+ and Cu-Zn superoxide dismutase and tended to increase superoxide dismutase content (P = 0.065). Zinc content in eggs increased linearly with supplementary organic zinc (N = 18, R2 = 0.363, P = 0.008) and with supplementary inorganic zinc (N = 18, R2 = 0.366, P = 0.008) treatment, but there was no difference between the source treatments of zinc. Therefore, our first hypothesis was supported, but our second one was not supported. We concluded that zinc supplementation is effective in enhancing zinc content in eggs and in improving antioxidant capacity in laying hens.

Alteration of growth performance, meat quality, antioxidant and immune capacity of juvenile Litopenaeus vannamei in response to different dietary dosage forms of zinc: Comparative advantages of zinc amino acid complex

An 8-week feeding trial was conducted to investigate the effects of different dietary dosage forms of zinc on growth performance, meat quality, antioxidant and immune capacity of juvenile Pacific white shrimp, Litopenaeus vannamei. Four isonitrogenous and isolipidic diets were formulated to contain different dosage forms of zinc, the control diet (no-supplemented zinc), I-Zn diet (120 mg kg−1 zinc from zinc sulfate), M-Zn diet (60/60 mg kg−1, zinc sulfate/zinc amino acid complex = 1:1) and Availa-Zn diet (60 mg kg−1 zinc from zinc amino acid complex), respectively. A total of 480 shrimp juveniles with initial weight 1.84 ± 0.02 g were randomly divided into four diets with four replications, each replication consisted of 30 shrimp. The results revealed that shrimp fed the M-Zn diet had significantly higher percent weight gain (PWG), specific growth rate (SGR), feed efficiency (FE), protein efficiency ratio (PER) and protein retention efficiency (PRE) than those fed the other diets. The significantly higher concentration of glucose (GLU) in hemolymph was observed in shrimp fed the M-Zn diet. Shrimp fed the diets supplemented with zinc amino acid complex had significantly lower values of drip and thawing losses of whole shrimp or muscle compared to those fed the control and I-Zn diets, which indicated that shrimp fed the diets supplemented with zinc amino acid complex had a better water-holding capacity. Moreover, shrimp fed the Availa-Zn diet had significantly higher the activities of alkaline phosphatase (AKP), acid phosphatase (ACP) and lysozyme (LZM) in hepatopancreas than those fed the control and I-Zn diets. Meanwhile, shrimp fed the M-Zn and Availa-Zn diets showed an up-regulation of expression levels of Cu-Zn sod, akp, acp and lzm in hepatopancreas. Principal component analysis (PCA) and multivariate correlation analysis demonstrated that shrimp fed the experimental diets exhibited significant variations and shrimp fed the M-Zn diet showed better growth response and meat quality. These findings could contribute to provide scientific evidences into the business application of zinc amino acid complex.

Zinc amino acid complex in association with chromium methionine improves the feed efficiency of finished Nellore cattle in the feedlot

Trace minerals are vital to the metabolism and performance of beef cattle and may improve meat quality. The objective of this study was to evaluate the effects of a Zn amino acid complex (ZnAA) fed alone or in association with a Cr methionine complex (CrMet) on the performance and meat quality of Nellore cattle finished in a feedlot. Three hundred thirty-six Nellore bulls were blocked by body weight (BW; 342 ± 24.5 kg) and assigned to one of the following three dietary treatments: a control diet containing 54 mg/kg of Zn from an inorganic source of minerals (CON); a diet providing 21.6 mg/kg of Zn from an inorganic source with 32.4 mg/kg of a Zn amino acid complex (ZnAA); and a diet providing 21.6 mg/kg of Zn from an inorganic source with 32.4 mg/kg of a Zn amino acid complex combined with 0.36 mg/kg of a CrMet complex (ZnCr). The total number of days on the diets was 130 days, with an initial 35-d period for dietary acclimation to the finishing diet. Statistical analysis was performed using the MIXED procedure of SAS with the pen as the experimental unit (36 pens). Blood parameters and meat quality were analyzed as repeated measures (from 72 animals; 2 animals/pen). The final BW, dry matter intake (DMI), and average daily gain (ADG) was similar among the treatments (P ≥ 0.261). The overall mean DMI, final BW, and ADG were 9.15 kg/d, 535 kg, and 1.49 kg/d, respectively. Feeding ZnCr improved efficiency (P = 0.011) compared with the ZnAA and CON bulls. Leucocytes, aminotransferase, β-hydroxybutyric acid, cholesterol, glucose, and cortisol were affected (P ≤ 0.038) by time but not by dietary treatment. Flight speed and serum cortisol level were unaffected (P ≥ 0.518) by dietary treatment. No significant treatment effects (P ≥ 0.169) were detected for hot carcass weight, fat, pH, temperature, liver, kidney, or KPH. Treatment tended to alter the area of the Longissimus muscle (P = 0.081). The Longissimus muscle area was greater for bulls fed ZnCr than for bulls fed ZnAA or CON (80.6 vs. 77.5 cm2). There was a tendency (P = 0.073) for decreased Warner-Bratzler shear force in animals fed ZnCr. Tenderness was improved by 12.3 % compared with CON. Individual fatty acids (P ≥ 0.171) and total fatty acids (saturated and unsaturated; P ≥ 0.392) did not differ among the treatments. These data suggest that finishing Nellore bulls fed ZnCr in a feedlot setting exhibited greater efficiency and tended to exhibit improved meat tenderness compared with bulls fed ZnAA.