Zn-Met Supplementation Research Articles

Effect of Dietary Zinc Methionine Supplementation on Growth Performance, Immune Function and Intestinal Health of Cherry Valley Ducks Challenged With Avian Pathogenic Escherichia coli.

This study was carried out to evaluate the effects of supplemental zinc methionine (Zn–Met) on growth performance, immune function, and intestinal health of meat ducks challenged with avian pathogenic Escherichia coli (APEC). A total of 480 1-day-old Cherry Valley male ducks were randomly assigned to 8 treatments with 10 replicates, each replicate containing 10 ducks. A 4 × 2 factor design was used with four dietary zinc levels (0, 30, 60, 120 mg Zn/kg in the form Zn–Met was added to the corn–soybean basal diet) and challenged with or without APEC at 8-days-old ducks. The trial lasted for 14 days. The results showed that a dietary Zn–Met supplementation significantly increased body weight (BW) of 14 days and BW gain, and decreased mortality during 7–14-days-old ducks (p < 0.05). Furthermore, dietary 30, 60, 120 mg/kg Zn–Met supplementation noticeably increased the thymus index at 2 days post-infection (2 DPI) and 8 DPI (p < 0.05), and 120 mg/kg Zn–Met enhanced the serum IgA at 2 DPI and IgA, IgG, IgM, C3 at 8 DPI (p < 0.05). In addition, dietary 120 mg/kg Zn–Met supplementation dramatically increased villus height and villus height/crypt depth (V/C) of jejunum at 2 DPI and 8 DPI (p < 0.05). The TNF-α and IFN-γ mRNA expression were downregulated after supplemented with 120 mg/kg Zn–Met in jejunum at 8 DPI (p < 0.05). Moreover, dietary 120 mg/kg Zn–Met supplementation stimulated ZO-3, OCLN mRNA expression at 2 DPI and ZO-2 mRNA expression in jejunum at 8 DPI (p < 0.05), and improved the MUC2 concentration in jejunum at 2 DPI and 8 DPI (p < 0.05). At the same time, the cecal Bifidobacterium and Lactobacillus counts were increased (p < 0.05), and Escherichia coli counts were decreased (p < 0.05) after supplemented with Zn–Met. In conclusion, inclusion of 120 mg/kg Zn–Met minimizes the adverse effects of APEC challenge on meat ducks by improving growth performance and enhancing immune function and intestinal health.

The effects of Zinc-Methionine on glucose metabolism and insulin resistance during late pregnancy in ewes

This study investigated the effects of dietary supplements of Zinc-Methionine (Zn-Met) on the zinc concentration of the blood and indices such as insulin resistance and glucose tolerance in late-pregnancy ewes to provide a practical solution to prevent metabolic diseases associated with energy status. In this research, 18 Makouei pregnant ewes were selected and randomized into 3 experimental groups: Group 1: Basal diet containing 10.3 mg Zn/kgDM and no zinc supplementation = CTR (Control); Group 2: Basal diet supplemented with low-dose zinc equivalent to the pregnancy requirements (30 mg Zn/kgDM) = LZN; Group 3: Basal diet supplemented with high-dose zinc (300 mg Zn/kgDM) = HZN. Blood samples for insulin resistance and glucose tolerance indices were collected according to standard methods. The results of this study indicated that supplementation of high-dose Zn-Met decreased (P < 0.05) blood glucose and tended (P < 0.1) to reduce the beta-hydroxybutyrate (BHB) concentrations. After intravenous injection of glucose and insulin, none of the glucose tolerance and insulin resistance indices were significant among groups (P > 0.05). However, the intravenous glucose tolerance test (IGTT) showed that the area under the curve (AUC) of serum glucose in the HZN group was numerically lower than that of the LZN and CTR groups. Furthermore, the numerically higher clearance rate (CR) of glucose and more negative glucose AUC following intravenous administration of insulin in Zinc-supplemented groups suggested that the ewes had greater insulin response than control group. The results showed a decrease in blood glucose concentration due to higher zinc intake after insulin injection and supported the evidence for improving insulin sensitivity. In addition, our results showed that ewes receiving zinc supplementation experienced a more favorable state of BHB or NEFA values. In conclusion, Zn-Met supplementation was found to have promising effects in improving energy metabolism in late pregnant ewes. However, further studies are needed to understand the mechanisms involved in regulating lipolysis and energy metabolism.

Zinc-methionine acts as an anti-diarrheal agent by protecting the intestinal epithelial barrier in postnatal Holstein dairy calves

This study compared the effects of supplementation of postnatal Holstein dairy calves with low doses of zinc-methionine (Zn-Met) or zinc oxide (ZnO) on growth performance, diarrhea incidence, and the integrity of the small intestinal epithelial barrier. Twenty-four male newborn Holstein dairy calves with similar body weight (42.0 ± 1.2 kg) received raw milk and starter containing zinc at 4.05 mg/kg and 176 mg/kg dry matter, respectively. All animals were randomly allocated to one of three groups (n = 8 per group): a control group (CON, without extra zinc supplementation), a Zn-Met group (receiving 455 mg of Zn-Met per day, equivalent to 80 mg of zinc per day), or a ZnO group (receiving 103 mg of ZnO per day, equivalent to 80 mg of zinc per day). The experiment lasted for 14 days. Zn-Met and ZnO were mixed with milk and fed to the calves. Body weight, height, length, and heart girth were measured on the morning of days 1, 7, and 15. Feed intake and fecal scores were recorded daily during the experimental period. Blood samples were collected on day 15 before morning feeding. Thereafter, the animals were euthanized and their small intestines were collected for examination of intestinal morphology and the expression levels of mRNAs encoding jejunal mucosal tight junction (TJ) proteins. The two different sources of zinc did not influence growth performance or diarrhea incidence in dairy calves during days 1–7 or 1–14 after birth. However, Zn-Met supplementation reduced the diarrhea incidence (35.7 % [Zn-Met] vs. 58.9 % [CON]) and improved the average daily gain (ADG) (500 g/d [Zn-Met] vs. 422 g/d [CON]) and feed efficiency (feed-to-gain ratio: 2.05 [Zn-Met] vs. 2.47 [CON]) significantly during the second week after birth (P < 0.05). Supplementation with Zn-Met improved the integrity of the intestinal mucosa barrier, as indicated by increases in the height of the ileal villi and the expression levels of mRNAs encoding jejunal mucosal TJ proteins (claudin-1, occludin, and zonula occludens protein-1), as well as a reduction in serum D-lactate concentration (P < 0.05). By contrast, no significant differences in the parameters examined were observed between the ZnO and CON groups. Overall, these findings suggest that Zn-Met supplementation lowers the incidence of diarrhea in postnatal Holstein dairy calves by reducing intestinal permeability, which sheds light on the effectiveness of zinc application as a potential treatment for diarrhea during early life calf rearing.

Effects of prepartum zinc-methionine supplementation on feed digestibility, rumen fermentation patterns, immunity status, and passive transfer of immunity in dairy cows

The aim of this study was to determine the effects of prepartum supplementation of zinc-methionine (Zn-Met) on feed digestibility, rumen fermentation patterns, and immunity status in dams and passive immunity transfer in their calves. A randomized complete design was used in this study. Forty multiparous Holstein dairy cows in late pregnancy (60 d before the expected calving date) were blocked by parity (2.1 ± 0.3), body weight (651 ± 52 kg), and expected calving date, and randomly assigned to 1 of 4 treatments. Cows were supplemented with Zn as Zn-Met at 0, 20, 40, or 60 mg/kg of dry matter (DM) from 60 d before expected calving date to the calving day. Though the nutrient digestibility was not affected by Zn supplementation, DM intake, Zn digestibility, and Zn deposition increased linearly with increasing Zn-Met supplementation. Ruminal pH and molar proportion of individual volatile fatty acids were similar, whereas a linear decrease and increase were observed in ruminal ammonia and microbial crude protein concentration, respectively, with increasing Zn-Met supplementation. Maternal serum concentration of alkaline phosphatase, carboxypeptidase, Cu and Zn superoxide dismutase, and total antioxidant capacity were greater in cows supplemented with >40 mg of Zn/kg of DM compared with the control group. With increasing Zn-Met supplementation, maternal blood concentration of IL-1 decreased linearly, whereas IL-2 and IL-6 increased linearly, and no differences were observed in IL-4. Concentration of nonesterified fatty acids and β-hydroxybutyric acids in maternal blood was similar between treatments. No difference was observed in colostrum composition with increasing Zn-Met supplementation. Concentration of Zn and immunoglobulins (including IgA, IgG, and IgM) in maternal blood did not differ among treatments. However, Zn concentration in colostrum and blood of calves increased linearly. The concentration of IgA and IgM in colostrum increased linearly with increasing Zn-Met supplementation, whereas no differences in immunoglobulins were observed in calf blood. In conclusion, Zn supplementation as Zn-Met at 40 of mg/kg of DM may improve antioxidant activity of dam and potentially increase passive immunity transfer in calves.

Effect of the Source of Zinc on the Tissue Accumulation of Zinc and Jejunal Mucosal Zinc Transporter Expression in Holstein Dairy Calves.

Simple SummaryDiarrhea is the main cause of death in newborn calves and is associated with antibiotic use and economic loss for dairy farms. In this study, we evaluated the effects of different sources of the mineral zinc (zinc oxide (ZnO) and zinc methionine (Zn-Met)) on the growth, incidence of diarrhea, tissue zinc accumulation, gene expression of jejunal zinc transporters and serum concentrations of zinc-dependent proteins in newborn Holstein dairy calves. We found that Zn-Met supplementation promoted growth and reduced diarrhea from the second week after birth. It also increased the levels of zinc in the serum and liver, the level of the transporter protein ZIP4 in the jejunal mucosa, as well as the serum alkaline phosphatase and metallothionein concentrations compared to the control group. ZnO supplementation had similar but less marked effects to Zn-Met supplementation. These results suggest that Zn-Met supplementation may be an alternative to antibiotics for the treatment of newborn calf diarrhea.Zinc is considered to be an anti-diarrheal agent, and it may therefore reduce the incidence of diarrhea in young calves. In the present study, we aimed to compare the effect of zinc source on growth performance, the incidence of diarrhea, tissue zinc accumulation, the expression of zinc transporters, and the serum concentrations of zinc-dependent proteins in neonatal Holstein dairy calves. Eighteen male newborn Holstein dairy calves were fed milk and starter diet supplemented with or without 80 mg zinc/d in the form of Zn-Met or ZnO for 14 days, and were then euthanized. Zn-Met supplementation improved average daily gain and feed efficiency, and reduced the incidence of diarrhea, compared with control calves (p < 0.05). It also increased the serum and hepatic zinc concentrations and the mRNA expression of the ZIP4 transporter in the jejunal mucosa of the calves (p < 0.05). In addition, the serum alkaline phosphatase activity and metallothionein concentration were higher in Zn-Met-treated calves than in control calves (p < 0.05). ZnO supplementation had similar effects, but these did not reach significance. Thus, Zn-Met supplementation is an effective means of increasing tissue zinc accumulation and jejunal zinc absorption, and can be used as an anti-diarrheal strategy in neonatal calves.

Effects of different types of zinc supplement on the growth, incidence of diarrhea, immune function, and rectal microbiota of newborn dairy calves

Neonatal diarrhea in dairy calves causes huge economic and productivity losses in the dairy industry. Zinc is an effective anti-diarrheal agent, but high doses may pose a threat to the environment. Therefore, we aimed to evaluate the effects of low-dose zinc supplementation on the growth, incidence of diarrhea, immune function, and rectal microbiota of newborn Holstein dairy calves. Thirty newborn calves were allocated to either a control group (without extra zinc supplementation), or groups supplemented with either 104 mg of zinc oxide (ZnO, equivalent to 80 mg of zinc/d) or 457 mg of zinc methionine (Zn-Met, equivalent to 80 mg of zinc/d) and studied them for 14 d. The rectal contents were sampled on d 1, 3, 7, and 14, and blood samples were collected at the end of the study. Supplementation with ZnO reduced the incidence of diarrhea during the first 3 d of life, and increased serum IgG and IgM concentrations. The Zn-Met supplementation increased growth performance and reduced the incidence of diarrhea during the first 14 d after birth. The results of fecal microbiota analysis showed that Firmicutes and Proteobacteria were the predominant phyla, and Escherichia and Bacteroides were the dominant genera in the recta of the calves. As the calves grew older, rectal microbial diversity and composition significantly evolved. In addition, dietary supplementation with ZnO reduced the relative abundance of Proteobacteria in 1-d-old calves, and increased that of Bacteroidetes, Lactobacillus, and Faecalibacterium in 7-d-old calves, compared with the control group. Supplementation with Zn-Met increased the relative abundance of the phylum Actinobacteria and the genera Faecalibacterium and Collinsella on d 7, and that of the genus Ruminococcus after 2 wk, compared with the control group. Thus, the rectal microbial composition was not affected by zinc supplementation but significantly evolved during the calves' early life. Zinc supplementation reduced the incidence of diarrhea in young calves. In view of their differing effects, we recommend ZnO supplementation for dairy calves during their first 3 d of life and Zn-Met supplementation for the subsequent period. These findings suggest that zinc supplementation may be an alternative to antibacterial agents for the treatment of newborn calf diarrhea.

Impacts of feeding zinc-methionine or chromium-methionine on performance, antioxidant status and physiological responses to transportation stress on lambs

Context Road transportation of farm animals is an unavoidable activity in animal husbandry, which may lead to the stress. Metabolic modifiers, such as minerals, may be an effective strategy to improve the performance and immune system of animals. Aims The present study examined the effects of chromium-methionine (Cr-Met) and zinc-methionine (Zn-Met) supplementation on animal performance and response to transportation stress. Methods Eighteen lambs (18–20 weeks of age) were randomly assigned to the following three dietary treatments for 10 weeks: (1) basal diet (control, 0.021 g/kg Zn and 0.0001 g/kg Cr); (2) basal diet with addition of 10 Cr-Met mg/kg DM (containing 1 mg/kg Cr); and (3) basal diet with addition of 500 Zn-Met mg/kg DM (containing 50 mg/kg Zn). After a 6-week supplementation period, the lambs were transported by road for 3 h. Key results Mineral supplements did not affect final bodyweight, average daily gain or feed conversion ratio. The blood cortisol and aspartate aminotransferase concentrations were increased (P &amp;lt; 0.05) immediately after transportation (AT1) in all groups; however, they were lower in supplemented lambs than in the control (P &amp;lt; 0.05). Animals fed Cr-Met or Zn-Met diets had a higher albumin concentration at AT1 than did the control group (P &amp;lt; 0.05). Lambs on the Zn-Met diet showed a higher blood triiodothyronine and triiodothyronine to thyroxin ratio at AT1 and at 24 h after transportation (AT2) than did lambs receiving the control diet (P &amp;lt; 0.05). Lambs fed the Cr-Met diet had a lower blood malondialdehyde at AT1 and AT2 than did the control lambs (P &amp;lt; 0.05). Total antioxidant capacity (TAC) was higher in the Zn-Met-supplemented group than in other groups (P &amp;lt; 0.05). Supplementation with dietary Zn-Met increased serum TAC concentration in the kidney tissue compared with the control (P &amp;lt; 0.05), but had no effect on superoxide dismutase and glutathione peroxidase activities. The Cr-Met group showed also a lower malondialdehyde concentration (P &amp;lt; 0.05) and higher TAC, superoxide dismutase and glutathione peroxidase activities in the liver tissue (P &amp;lt; 0.05). Conclusions Dietary supplementation with 10 mg Cr-Met/kg (1 mg Cr) in comparison to 500 mg Zn-Met/kg (50 mg Zn) improved the stress response of lambs subjected to a short-time road transportation, whereas growth performance was not affected. Implications The administration of Cr-Met or Zn-Met to diet of lambs before transportation could reduce the adverse effects of road transportation stress.

Reproductive and Productive Efficiency of Maghrebi Dairy She-Camels Fed Diets Supplemented with Zinc-Methionine.

This study is aimed at evaluating the effect of dietary zinc-methionine (Zn-Met) supplementation during 3months prepartum up to 9months postpartum on reproductive performance, blood biochemical, and milk production of lactating she-camels besides growth performance of their calves. Twenty pregnant Maghrebi she-camels (439.49 ± 11.57kg; 3-5 parties) were divided into four similar groups. Animals were fed the basal diet (G1) or the basal diet supplemented with Zn-Met at levels of 30mg (G2), 40mg (G3), and 50mg (G4)/kg diet. Results revealed that IgA, IgM, and IgG concentrations in colostrum, monthly milk yield, and lactation period were significantly increased in Zn-Met-supplemented groups. Milk contents of fat, ash, and total solids improved (P < 0.05) in G4 as compared with other groups. Pre- and postpartum Zn, T3, T4, P4, and E2 concentrations in plasma and milk Zn level were higher (P < 0.05) in all Zn-Met-supplemented groups. Postpartum first estrus interval, number of services/conception, days open, pregnancy rate, duration of placental drop, and calving interval improved (P < 0.05) in G4. Weaning weight and average daily gain of calves were enhanced all in Zn-Met-supplemented groups. Conclusively, the inclusion of Zn-Met especially at a level of 50mg/kg diet, 3months prepartum up to 9months postpartum, led to better productive and reproductive performance, immunity of she-camels, and growth performance of their offspring.

Effects of dietary Zn-methionine supplementation on the laying performance, egg quality, antioxidant capacity, and serum parameters of laying hens.

This study was to determine the effects of dietary Zn-methionine (Zn-Met) supplementation on the laying performance, egg quality, antioxidant capacity, and serum parameters of laying hens. Jingh ong-1 strain laying hens (n = 720, 49 wk of age) were randomly assigned to 6 treatments with 6 replications of 20 birds. The control was fed a basal diet supplemented with 80mg of Zn/kg as Zn sulphate of diet and the 5 groups were fed a basal diet supplemented with 20, 40, 60, 80, and 100mg of Zn/kg as Zn-Met of diet for 10 wk, respectively. At the terminal experiment, there were significant differences between control and 80mg/kg Zn-Met group in feed intake (P < 0.05) and feed conversion ratio (FCR) (P < 0.01). Egg weight (P < 0.05) and albumen height (P < 0.01) reduced and were not significantly influenced by supplemental 80mg/kg Zn-Met group until being stored 15 d as compared to the control. Zn-Met group in 100mg/kg significantly increased haugh unit (P < 0.05) as compared to the control. The activity of MDA in serum had a linear decrease in 20 to 100mg/kg Zn-Met. The activity of CAT in liver and GSH-Px in serum had quadratic effects in response to the Zn-Met treatments. Compared to the control, 60mg/kg Zn-Met group increased the T-AOC, GSH-Px activity in serum (P < 0.01), and the T-AOC (P < 0.05), CuZnSOD (P < 0.01), GSH-Px (P < 0.01) activity in liver. Compared with the control, the concentration of serum ionic Ca in 80, 100mg/kg Zn-Met treatments reduced (P < 0.01) significantly while the activity of serum alkaline phosphatase (AKP) increased in the Zn-Met groups of 40, 60, and 80mg/kg (P < 0.01), and 100mg/kg (P < 0.05). In conclusion, dietary Zn-Met supplementation at 60 to 80mg/kg had more positive effects on performance, egg quality, and antioxidant capacity in laying hens as compared to 80mg/kg ZnSO4.

145 Effect of Dietary Organic Zinc Levels on Boar (Sus scrofa domesticus) Sperm DNA Fragmentation Dynamics

Zinc (Zn) is essential for the development and activity of sperm, although its cytotoxic effect on sperm has been little studied. This study evaluated the effect of organic Zn; that is, Zn-methionate (Zn-Met), on the DNA fragmentation of boar sperm. Domestic boars (York × Landrace, Sus scrofa domesticus; n = 15) were randomly allocated into 3 levels of Zn dietary concentrations: 25 (Control), 150, or 200 ppm. Sperm DNA fragmentation dynamics were evaluated over an 8-wk period after Zn-Met supplementation. The Sperm-Sus-Halomax® Kit (Halosperm SL, Madrid, Spain), a 1:1 mixture of SYBR I (10×; Invitrogen Molecular Probes, Thermo Fisher Scientific, Waltham, MA, USA) in Vectashield Mounting Medium (Vector Laboratories Inc., Burlingame, CA, USA) for DNA staining, and fluorescence microscopy (Nikon Eclipse 80i; Nikon, Tokyo, Japan) were used to analyse DNA fragmentation dynamics; that is, sperm chromatin dispersion (SCD) test, of the boar sperm. Samples were diluted 2:10 (v:v) in either (a) Beltsville Thawing Solution (BTS) extender, or (b) PBS, to determine the effects, if any, of extender. Extended sperm were stored at 15°C for 8 days for daily SCD testing. Data were analysed as a completely randomised design with repeated-measures serially in time (SAS Institute Inc., Cary, NC, USA). Main effects of the variables (i.e. dietary Zn and extender) and their interaction were studied. Means were compared using Tukey´s test, with significance set at the &lt;0.05 α-level. Supplementation of the diet with 200 ppm of Zn-Met had an adverse effect on the integrity of pig sperm DNA from the beginning of supplementation to the last day of the experiment (i.e. fresh ejaculate 0 h = 9.44% fragmented, motility = 79.6%). However, Control and 150 ppm Zn-Met dietary levels did not significantly affect sperm DNA integrity (i.e. fresh ejaculate 0 h = 1.43% and 1.73% fragmented and motility = 84.1% and 84.5%, respectively). With regard to the semen extenders BTS and PBS, there was no difference (P &gt; 0.05) in sperm DNA fragmentation dynamics for the first 3 days in extender: Day 3 = 4.09 and 6.45%, respectively. However, the sperm DNA fragmentation index was different (P &lt; 0.05) between extenders BTS and PBS based on extended sperm for Day 4: 4.28 and 7.28%, respectively, through Day 8 (5.52 and 10.02%). These results demonstrated the importance of providing the correct amount of organic Zn in boar diets and potential impacts on reproduction.

Effects of Dietary Supplementation of Zinc Oxide and Zinc Methionine on Layer Performance, Egg Quality, and Blood Serum Indices.

The objective of this study was to evaluate the effectiveness of dietary zinc oxide (ZnO) and zinc methionine (Zn-Met) supplementation on layer performance, quality of egg, some blood constituents, and oxidative status in blood of laying hens. A total of 120 laying hens (Hisex Brown) 22-week-old were indiscriminately allotted into five groups of 24 hens with six replications (four birds/replicate). A complete randomized design experiment was performed including control (basal diet), two levels of ZnO (50 and 100mg/kg basal diet), and two levels of Zn-Met (50 and 100mg/kg basal diet) through 22 to 34weeks of age. Supplementation of 100mg of Zn-Met significantly (P=0.001) increased feed intake compared to other treatment groups. The groups supplemented with 50mg of ZnO and 100mg of Zn-Met reported the significantly higher egg production rate (P=0.002) and egg mass (P<0.001) compared to other treated groups. All traits of egg quality were not statistically (P<0.05 or 0.01) affected by ZnO or Zn-Met supplementation except shell thickness, Haugh unit score, and yolk to albumin ratio. Dietary supplementation of either ZnO or Zn-Met did not affect the oxidative parameters in serum except the activity of Cu-Zn-SOD. Serum triglyceride, total cholesterol, and LDL cholesterol (low-density lipoprotein) were significantly (P<0.05) affected by Zn supplementation, while HDL cholesterol (high-density lipoprotein) did not affect. Compared to the control group, supplementation of ZnO or Zn-Met increased serum content of zinc with no differences among supplemental zinc doses. It could be concluded that dietary inorganic (ZnO) and organic (Zn-Met) supplemented up to 50 and 100mg/kg, respectively, can be used as effective supplements to improve productivity of laying hens, serum zinc level, lipid profile (triglyceride and LDL cholesterol), and activity of Cu-Zn-SOD.

Effect of dietary supplementation of organic zinc on laying performance, egg quality and some biochemical parameters of laying hens

This study was conducted to evaluate the effects of zinc methionine (Zn-Met) supplementation on the performance, egg quality, antioxidant status and some biochemical parameters of blood serum in laying hens from 22 to 34weeks of age. A total of 120 Hisex Brown laying hens of 22-week-old were randomly allocated into five treatments with six cage replicates for each (four hens/replicate). Dietary treatments consisted of the basal diet with no Zn-Met supplementation (control group) and basal diet supplemented with 25, 50, 75 or 100mg Zn-Met/kg diet. No significant differences were observed on body weight, body weight gain or feed conversion ratio due to dietary Zn-Met supplementation. However, highly significant impact was observed on daily feed intake. Egg number, egg weight and egg mass were increased in the group fed diet supplemented with the highest level of Zn-Met (100mg/kg of diet) as compared to other groups. All egg quality traits were statistically (p>.05 or .01) affected as a response to dietary Zn-Met supplementation except egg shape index, shell percentage and yolk index. In comparison with the control group, dietary supplementation of 25, 50, 75 or 100mg Zn-Met/kg decreased serum triglyceride and LDL-cholesterol levels. Serum cholesterol level was increased with all dietary levels of Zn-Met in comparison with the control group. Dietary Zn-Met supplementation increased the serum content of zinc, where the highest values were recorded with 50 and 100mg Zn-Met/kg diet. Dietary Zn-Met levels did not affect the antioxidant indices in blood serum except for the activity of copper-zinc superoxide dismutase (Cu-Zn-SOD). The activity of Cu-Zn-SOD was increased with Zn-Met supplementations with no differences among supplemental zinc levels. It is concluded that dietary Zn-Met supplementation reduced serum triglyceride, LDL-cholesterol and increased Zn status and resulted in promoting antioxidant ability of laying hens, and the addition of 100mg Zn-Met/kg to layer diet was appropriate for improving the above parameters in addition to egg production indices and Haugh unit score.

Effects of organic zinc supplementation in weaned calves

The aim of the study was to investigate the effect of organic zinc supplementation in calves on serum zinc (Zn) concentrations, selected metabolic profile indicators and serum immunoglobulin (Ig) concentrations. The trial included 2 groups (n = 10) of weaned female calves. The Zn-Methionin calves (group Zn-Met) were supplemented with 30 mg Zn-Met/kg dry matter (DM)/day (BIOPLEX® Zn, Alltech, USA) for 90 days; the control calves (group C) received the same diet without organic zinc supplementation. Compared to the control group, organic Zn treatment significantly increased serum Zn concentration (P &lt; 0.05), superoxide dismutase (SOD) activity (P &lt; 0.01) and total Ig (P &lt; 0.01) in the group Zn-Met at the beginning (7 days from the start of Zn-Met supplementation) of the trial. At the end of the trial (day 90) serum total protein (TP) (P &lt; 0.05), albumin (P &lt; 0.01), urea (P &lt; 0.01), SOD (P &lt; 0.01), copper (Cu) (P &lt; 0.05), Zn (P &lt; 0.01) and Ig (P &lt; 0.05) concentrations were significantly higher in the Zn-Met calves. In the control group alkaline phosphatase (ALP) activity was significantly (P &lt; 0.01) higher on day 90. A positive correlation between zinc concentrations, ALP, and SOD activities in serum, and a negative correlation between zinc and copper concentrations were demonstrated. Dietary Zn-Met supplementation in calves markedly influenced the metabolic profile and serum immunoglobulin concentrations. Compared to the control group, the Zn supplemented group showed a significantly (P &lt; 0.05) lower ALP and significantly greater SOD serum activity (P &lt; 0.01) at the end of the trial. Total Ig concentrations were significantly higher in the Zn treated group (day 7: P &lt; 0.01 vs. day 90: P &lt; 0.05).

Dose–responses of zinc–methionine supplements on growth, blood metabolites and gastrointestinal development in sheep

The effects of zinc-methionine (Zn-Met) supplementation on growth, blood metabolites and gastrointestinal development were investigated in two experiments with sheep. The objective of Experiment 1 was to determine the effects of Zn-Met supplementation on hormones and metabolites involved in growth and energy balance regulation, while Experiment 2 aimed to determine the effects of Zn-Met on feed intake, body weight, gastrointestinal development and liver glycogen concentration in lamb. The animals were assigned to groups with different concentrations of dietary Zn-Met (0, 0.4, 0.8 and 1.2g/day) in both experiments. In Experiment 1, feeding different doses of Zn-Met increased plasma insulin-like growth factor 1 (IGF-1) concentration, but it linearly decreased plasma growth hormone (GH). No differences were observed in blood cortisol, insulin and glucose concentrations among the treatments. In Experiment 2, addition of Zn-Met to the diets did not lead to changes in the body weights of the lambs. Both average daily gain and dry matter intake (DMI) increased linearly with increasing concentrations of dietary Zn-Met. Lambs receiving Zn-Met showed higher liver glycogen concentrations than the control. While significant increases were observed in the villus height and crypt depth in the duodenum and jejunum as a result of Zn-Met supplementation, no change was detected in blood glucose concentrations (p>0.05). Our findings suggest that dietary Zn-Met may improve growth, energy balance and gastrointestinal development in sheep.

Immunological Responses of Broiler Chicks Can Be Modulated by Dietary Supplementation of Zinc-methionine in Place of Inorganic Zinc Sources

Male broiler chicks were fed graded levels of organic zinc (zinc-methionine) supplementation to investigate the effects of partial or complete substitution of the organic zinc source for inorganic ones on the development of lymphoid organs and immunological responses. A total of 450 day-old male broilers were distributed into groups of 10 chicks and randomly assigned to nine experimental diets during a 42-day feeding trial. Dietary treatments consisted of two basal diets supplemented with 40 mg/kg added zinc as feed-grade Zn sulfate or Zn oxide in which, Zn was replaced with that provided from zinc-methionine (ZnMet) complex at the levels of 25, 50, 75 or 100%. Two randomly-selected birds from each pen replicate were bled and then slaughtered by cervical cutting on the final day of the trial to measure leukocyte subpopulations and relative weights of lymphoid organs. Among lymphoid organs, only thymus weight was affected (p<0.05) by dietary treatments. The sulfate-supplemented birds were heavier (p<0.01) in relative weight of thymus than oxide-supplemented birds. The 10 days of age-assessed cutaneous hypersensivity reaction was stronger in chicks fed ZnMet-containing diets. Dietary ZnMet supplementation caused (p<0.05) an increase in proportion of lymphocytes and consequently a decrease in heterophil to lymphocyte ratio. Diet fortification by zinc-methionine complex increased (p<0.01) Newcastle antibody titer at 19 days of age. Also, a similar response was observed in antibody titers at 6 and 12 d after infectious bronchitis vaccine administration. There was no significant effect of replacement of dietary zinc on antibody titer against infectious bursal disease virus (IBDV) at the 6 th d post-vaccine inoculation; however, at d 12 after vaccination, ZnMet-fortified diets improved antibody titer against IBDV. Although dietary inclusion of ZnMet had no marked effect on primary antibody titer against sheep erythrocytes, effective responses were observed during secondary reaction from the viewpoint of both total antibody and immunoglobulin Y (IgY) titers. From the present findings, it can be concluded that dietary supplementation with organic zinc improves both cellular and humoral immune responses. It is necessary to replace 75% of supplemental inorganic zinc with organic ZnMet complex to achieve the optimum immunological responses in broiler chicks.

Bioavailability of zinc from zinc sulfate and different organic zinc sources and their effects on ruminal volatile fatty acid proportions

Twenty-four Angus steers were used to determine the effects of dietary zinc (Zn) level and source on Zn metabolism and ruminal volatile fatty acid (VFA) patterns. All steers were fed a low Zn diet (18.8 mg Zn per kg) for 42 days prior to assignment to dietary treatments. Treatments consisted of: (1) control (low Zn diet), (2) Zn sulfate (ZnSO 4), (3) Zn methionine complex (ZnMet) and (4) Zn glycine complex (ZnGly). The Zn sources were added to provide 20 mg of supplemental Zn per kg diet. A 5-day total collection of feces and urine was conducted beginning on day 14 of the study. Liver biopsy samples were obtained on days 0 and 42 for Zn analysis, and ruminal fluid was collected on day 42 for VFA and ruminal soluble Zn determination. Plasma samples were obtained on days 0, 2, 19, 21, and 42 for determination of plasma Zn and alkaline phosphatase activity. Urinary excretion of Zn was higher ( P<0.05) in steers supplemented with ZnMet or ZnGly than in controls. Apparent absorption and retention of Zn were not significantly affected by treatment, but tended to be higher in steers receiving ZnGly. Liver Zn concentrations were higher ( P<0.05) on day 42 in steers supplemented with ZnGly, compared to steers receiving control, ZnMet or ZnSO 4 treatments. Plasma Zn concentrations were higher ( P<0.05) for the ZnGly and ZnMet treatments compared to the control on day 42. Plasma alkaline phosphatase was not affected by treatment. Ruminal soluble Zn concentrations were higher ( P<0.05) in steers fed ZnMet compared to those fed the control or ZnSO 4 diets. Total VFA concentrations were higher ( P<0.05) in steers fed the control and ZnSO 4 treatments than in those receiving ZnGly or ZnMet. Steers supplemented with ZnMet had a higher ( P<0.05) molar proportion of propionate and lower ( P<0.05) molar proportions of butyrate and valerate than controls. Compared to the control treatment, valerate was the only VFA affected by ZnSO 4 or ZnGly supplementation. Results suggest that Zn from ZnGly was more bioavailable than ZnSO 4 or ZnMet. However, ZnMet supplementation resulted in the highest ruminal soluble Zn concentrations and altered ruminal VFA proportions to the greatest extent of the Zn sources evaluated.

Effects of dietary supplements of zinc-methionine on milk production, udder health and zinc metabolism in dairy goats.

Twenty-two Murciano-Granadina dairy goats were used to investigate the effects of organic Zn supplementation of a diet containing a high level of inorganic Zn. Goats were kept in pens, machine milked once a day throughout lactation and fed a diet based on a dehydrated mixture of whole-plant maize and alfalfa ad libitum, alfalfa pellets, barley grain and a concentrate mixture. Treatments were: (1) control, and (2) supplemented with 1 g/d Zn-Methionine (Zn-Met) included in the concentrate mixture. After parturition, goats were blocked in week 3 and dietary treatments were applied until week 23. From weeks 3-20, feed intake, milk yield, milk composition, milk somatic cell count (SCC), and udder health were measured. In week 21, all goats were injected intraperitoneally with 1 g/d DL-methionine for 5 d to establish the effects of methionine under the conditions of udder stress induced by hand milking on the second day. During weeks 22 and 23, diet digestibility, and N and Zn balance were determined. Dry matter intake, milk yield, and milk contents of total solids, fat, total and true protein, and casein did not differ between treatments, but whey protein and non-protein nitrogen contents were significantly lower for the Zn-Met group. Milk SCC tended to decrease as a result of Zn-Met supplementation but differences between treatments were not significant when halves with persistent infection were excluded. Hand milking increased SCC in both groups, but udders of supplemented goats showed a lower reaction. Apparent absorption of N significantly increased and Zn retention tended to increase in Zn-Met supplemented goats. We conclude that Zn-Met supplementation can enhance resistance to udder stress in dairy goats. Effects were attributed to the organic Zn and not to the methionine component. Zn retention and protein utilization were also improved by the Zn-Met supplement.

Effects of Supplementary Mineral Methionine Chelates (Zn, Cu, Mn) on the Performance and Eggshell Quality of Laying Hens

A layer experiment was conducted to determine the effects of supplementary methionine chelates (Cu, Zn and Mn), individual or in combination, on laying performance, eggshell quality, gizzard erosion, and IgG level of serum for 8 weeks. Five hundred 96-wk-old force molted ISA Brown layers were assigned to five dietary treatments. Basal diet was formulated to meet or exceed the nutrients requirements listed in NRC (1994). Five experimental diets were control, Zn-methionine chelate (Zn-Met) supplemented, Cu- methionine chelate (Cu-Met) supplemented, Zn-Mn-methionine chelate (Zn-Mn-Met) supplemented and Zn-Mn-Cu-Met supplemented diet. Each treated diet was supplemented with respective mineral(s) at the level of 100 ppm in the form of methionine chelate. Egg production was increased by Cu-Met supplementation but decreased by Zn-Met supplementation. Egg weight was significantly (p<0.05) lower in Cu-Met treatment than those of the control and Zn-Met treatment. Specific gravity of eggs and eggshell strength were highest and soft egg production was lowest in Cu-Met treatment. Gizzard erosion index was significantly increased by supplementation of Cu- Met, Zn-Mn-Met or Zn-Mn-Cu-Met. Zinc content in liver significantly increased by Zn-Met, but not by Zn-Mn-Cu-Met treatment. In conclusion, 100 ppm Cu in Cu-Met chelate improved laying performance and eggshell quality but also increased gizzard erosion index. Supplementation of Zn-Met or its combination with other mineral chelates had no beneficial effects on laying performance and eggshell quality. (Asian-Aust. J. Anim. Sci. 2003. Vol 16, No. 12 : 1804-1808)

Effects of zinc-methionine on performance of Angora goats

Effects of supplementation with zinc-methionine (Zn-Met), a source of potentially rumen protected methionine and zinc (Zinpro 40, Edina, MN), on mohair growth, BW gain and blood metabolites were investigated in Angora goats. Forty yearling Angora goats (20 wethers and 20 doelings) were offered a basal diet (11.2% CP, 22 ppm Zn, 2.3 Mcal/kg DM) at 4% BW of DM for 120 days. The treatments (1–5) were: 1, 3 and 5 g/day of Zn-Met, 150 mg/day of zinc oxide and control (no supplementation). Supplementation of the diet with Zn-Met (1, 3 and 5 g/day of Zn-Met) increased ( P < 0.07) ADG (65.5 versus 55.9 g/day for control). ADG for goats receiving ZnO was lower ( P < 0.04) than for goats receiving a similar amount of Zn from 3 g/d Zn-Met (50.5 versus 62.9 g/day), although Zn-Met inclusion in the diet numerically ( P = 0.13) increased clean mohair production, which also changed quadratically ( P < 0.09) as Zn-Met level increased (1.59, 1.51, 1.62, 1.60 and 1.59 kg in 120 days) for treatments 1, 2, 3, 4 and 5, respectively. Supplementation of the diet with Zn-Met increased ( P < 0.03) plasma Zn concentration (0.92 versus 0.72 mg/l for control); there were no differences in plasma Zn concentration between goats receiving the ZnO supplement and goats receiving a similar amount of Zn from Zn-Met (0.87 versus 0.92 mg/l; P > 0.56). Plasma methionine concentration was not affected by Zn-Met supplementation ( P > 0.53). In summary, supplementation of a Zn-adequate diet with Zn-Met increased ADG by yearling Angora goats regardless of level of Zn-Met added. Supplementation of 1 g Zn-Met may have positive effect on ADG and mohair growth when diet contains about 20 ppm Zn.

Influence of Dietary Zinc Methionine Supplementation on Eggshell Quality in Laying Hens under Hot Climate Environment.

We have examined the influence of dietary zinc-methionine (Zn-Met ; Zn 80 g/kg, Met 160 g/kg) supplementation (500 mg Zn-Met/kg diet) on eggshell quality in laying hens under hot climate environment. The experiment was started from June 15, 1995 and continued for 12 weeks. The egg production and the quality of eggshell were measured at 0, 4, 8 and 12 weeks of experiment.The average of daily maximum temperatures in the first week was 25.5°C and then increased gradually until 8 weeks of experiment (37.5°C). Thereafter it was kept for 3 weeks and then decreased toward the end of the experiment. The rate of egg production at 4 weeks of experiment was significantly lower than that at the beginning of experiment. The number of abnormal eggs changed similarly to the variation of ambient temperatures. Eggshell weight decreased significantly from 0 to 8 weeks of experiment and thereafter increased significantly. Eggshell thickness at 8 weeks of experiment was the thinnest through the experimental period. Eggshell strength decreased gradually from 4 to 8 weeks of experiment and then increased significantly. Dietary Zn-Met supplementation did not affect eggshell quality. These results suggest that poor eggshell quality under hot climate environment was not improved by dietary Zn-Met supplementation at the level tested.