جستجوی مقالات مرتبط با کلیدواژه "l- methionine" در نشریات گروه "علوم دام"

Introduction : 

Diarrhea is the main cause of calf mortality in the first two weeks after birth. Even when calves recover from diarrhea, they may subsequently show impaired growth. Considering this fact and especially following the ban of antibiotics in many countries, it is very important to identify effective anti-diarrheal supplements for use in suckling calves. Zinc is an effective anti-inflammatory and anti-diarrheal substance that improves the function of the immune system, reduces the number of pathogenic bacteria and increases the relative abundance of beneficial microbes in the digestive system. It is thought that the mechanisms of anti-diarrheal effect of zinc element are due to regulation of intestinal fluid transfer and mucosal integrity, strengthening of immunity and modulation of oxidative stress. The purpose of this experiment is to investigate the use of different proportions of organic (methionine-zinc) and inorganic (zinc oxide) sources of zinc to prevent diarrhea, improve the condition of the immune system and performance indicators of suckling calves. 

A total of 50 suckling Holstein calves were used over 70 days in a completely randomized design with 5 treatments and 10 replications. The experimental treatments were different proportions of organic and inorganic zinc supplements, including 1) zinc supplementation, 100% Methionine-zinc 2) combination of 75% methionine-zinc and 25% zinc oxide, 3) combination of 50% methionine-zinc and 50% zinc oxide, 4) combination of 25% methionine-zinc and 75% zinc oxide, and 5) 100% zinc oxide. All treatments received 1.96 mg of zinc supplementation per kilogram of body weight. Zinc supplements mixed with milk were fed to the calves from day one to day 14, and performance monitoring continued for 70 days. The stool score was evaluated on a scale of 1 to 4. Diarrhea was defined as the presence of grade 3 or 4 stools for 2 consecutive days. Data were analyzed in a completely randomized design using the GLM procedure of SAS. For variables measured over time (average daily gain, dry matter intake, and feed conversion ratio), time was added to the model as a repeated factor. 

The results showed that experimental treatments did not significantly effect the average daily gain, dry matter intake, and feed conversion ratio of the calves fed with Different ratios of mineral (zinc oxide) and organic (methionine-zinc) sources of zinc. In addition, the average of fecal consistency score did not differ significantly among the treatments. The results blood analysis demonstrated that treatment 100% methionine-zinc had higher level of concentration alkaline phosphatase. However, among the treatments contained methionine-zinc, a decrease in the ratio of methionine-zinc resulted in a decrease in Alkaline phosphatase concentration. Higher ratios of zinc oxide caused a significant decrease in the concentration of superoxide dismutase in the blood on the 14th and 70th day of the experiment. Also, on the 70th day of the test, the antioxidant capacity of whole blood was significantly higher in treatments containing methionine-zinc than in treatment %100 zinc oxide. The results showed that other blood parameters were not significantly influenced by the treatments in this study. In general, production performance did not change in different ratios of organic and mineral sources, the lack of effect of replacing zinc oxide with methionine-zinc on the performance of the present calves may be due to the provision of sufficient levels of zinc for all calves. So that the zinc supplement, taking into account its purity percentage, reached the same amount (1.96 mg of zinc supplement per kilogram of body weight) in all treatments. 

In the present study, overall production performance and blood parameter concentrations did not change with different ratios of organic and mineral sources. However, the activity of antioxidant enzymes was higher with higher ratios of the organic supplement (methionine-zinc) compared to the mineral source (zinc oxide). The lack of positive effect of replacing zinc oxide with methionine-zinc on the performance of the present calves may be due to the provision of sufficient levels of zinc for all calves. And it can be said that when a mineral is supplied at a sufficient level, the chemical form and bioavailability of resources are less important on performance.

Although minerals include a small part of the total cost of poultry feed, they perform special functions in the body. Given that today's birds are primarily raised under stressful conditions (including high production demands, environmental stress, heat, and exposure to various other stress factors), their nutrient metabolism, including the absorption of minerals, has changed. This has led to decreased feed consumption, reduced mineral absorption, and consequently, increased excretion of minerals. Minerals that serve as cofactors for many enzymes are crucial; thus, to support proper functioning and enhance the immune system's response, higher amounts of these nutrients are required in diets. Chromium (Cr) is a critical micronutrient for humans and animals. It contributes to physiological and nutritional efficiency. Chromium increases glucose glycogenesis, promotes glucose transport, and increases protein synthesis. Chromium is important in protein digestion and reduction of lipid peroxidation and increased growth production. Chromium deficiency is associated with reduced growth rate, and glucose, and protein metabolism. Under environmental, nutritional, and hormonal stress, the benefits of chromium supplementation clearly demonstrated. Considering that with the increase in age and egg size, the egg quality decreases, and also the function of the immune system decreases at the late phase of egg production. Therefore, supplementation of layer hen diets with some nutrients at the end of the production period can improve the egg quality and potentiate the humoral immune response. Thus, the subject of the current study was to investigate the effects of dietary supplementation of chromium-methionine on egg laying performance, egg quality traits at different storage times and temperatures, humoral immune response, and some blood biochemical parameters of laying hens at late–phase of the egg production cycle.

A total of 120 Leghorn laying hens (Hy-line W36, 73 weeks- old) were assigned in a completely randomized design with 6 dietary treatments, 5 replicates and 4 laying hens in each replicate for 6 weeks. The experimental treatments were 6 levels of chromium-methionine supplementation (0, 400, 800, 1200, 1600, and 2000 μg/kg of diet) of corn-soybean meal-based diet. The hens were housed in a 60 × 60 × 40 cm cage. All hens were housed in an environmentally controlled house with temperature maintained at approximately 25ºC. The house had controlled ventilation and lighting (16L: 8D). All hens were supplied with feed and water ad libitum. The hen-day egg production, egg weight, egg mass, feed intake, and feed conversion ratio were recorded daily. The feed conversion ratio was expressed in kilograms of feed consumed per kilogram of the egg mass. The effects of organic chromium supplementation of laying hens on egg quality traits were evaluated every 2 weeks at 75, 77, and 79 weeks of age. The egg shape index was calculated by dividing egg length to egg width. At the end of the experiment, to measure certain blood parameters, one bird from each replicate was selected, and blood was drawn from the wing vein. After preparing the serum, the concentrations of triglycerides, cholesterol, total protein, albumin, globulin, uric acid, alanine transaminase, aspartate transaminase, glucose, and malondialdehyde were measured using Pars Azmoon kits according to the manufacturer's instructions.

Supplementing the diet with chromium-methionine had a significant effect on laying performance (including feed intake, feed conversion ratio, and egg production) and egg quality traits (such as eggshell weight, yolk color, yolk weight, albumen height, and Haugh unit). The results showed that birds fed 2000 µg/kg chromium-methionine had the lowest feed intake and the best feed conversion ratio and egg production percentage were observed with the addition of 1600 and 2000 g/kg organic chromium. By suppressing stress factors, chromium can increase the ovulation rate and increase the percentage of egg production. Addition of organic chromium except 2000 μg/kg improved albumen height and Haugh unit compared to the control group. The interaction effect between egg storage time and storage temperature on the yolk height and yolk percentage, albumen and yolk pH were significant. Carotenoids are responsible for the color of the yolk and they are a part of the fat-soluble compounds, so any factor that can improve the digestion and absorption of fats will probably lead to an increase in the color of the egg yolk. Haugh unit is a measure to determine the quality of egg white, which determines the quality of the egg. The higher HU means better egg quality (fresher, higher quality eggs have thicker whites). Blood serum cholesterol of chickens fed with 800 µg/kg of chromium-methionine decreased compared to the control group. The lowest serum concentration of malondialdehyde was observed using 1600 and 2000 µg/kg organic chromium. Addition of 1600 µg/kg of chromium-methionine increased total immunoglobulin production against sheep red blood cells. The effects of dietary chromium supplementation on improving immune responses can be attributed to its antioxidant activity. By enhancing antioxidant activity, chromium reduces the production of corticosterone, a potent suppressor of immune system function. This reduction in corticosterone levels prevents the decrease in lymphocyte production and proliferation, ultimately supporting the continued production of antibodies.

In total, dietary supplementation of 1600 μg/kg chromium-methionine can improve egg laying performance including feed conversion ratio, egg production, and egg mass, as well as egg quality traits such as egg shell weight and albumen height of laying hens at the late-phase of laying cycle. Supplementation of layer diets with 1600 μg/kg organic chromium improved the humoral immune response at the late-phase of egg production cycle by increasing the production of total immunoglobulin against sheep red blood cells.

Methionine is the first limiting amino acid in the poultry diet, and it plays essential roles in energy production and protein synthesis, increasing the growth performance of broiler chickens. This trial was conducted to compare the effect of L- and DL-Methionine on hatchability, productive performance and biochemistry of some blood parameters of broiler chicken from 1 to 7 day of age. On days 16 of incubation, 800 fertile egg (Ross 308) were randomly divided between 8 treatments (and 4 replicates) including 3 levels of L-Methionine (10, 20 and 30 mg), 3 levels of DL-Methionine (10, 20 and 30 mg) and two control treatments including negative (no injection) and positive (injection of 200 microliters of saline) control. Results showed that all treatments significantly (p<0.05) decreased the hatchability, without no effect on chick weight, chick to egg weight ratio and feed intake from 1 to 7 days of age. Birds received 30 mg L-Methionine showed the best BWG (27.3 g) and FCR (0.62). Likewise, 30 mg L-Methionine increased the carcass to live weight ratio (50.5) significantly (p<0.04). The applied treatments compare to the negative control group significantly (P<0.04) decreased triglyceride content of serum in the chickens. In general, the results of this research showed that injection of 30 mg of L-methionine compared to DL-methionine can lead to increased performance and improved carcass ratio in 7 days.

Coccidiosis is a serious problem in the poultry industry, and medication is required continuously. There are several approaches to the control of coccidiosis. Several drugs have been used in the control of coccidiosis. The ionophore antibiotics such as lasalocid, maduramicin, monensin, narasin, and salinomycin are extensively used in poultry feed for the prevention or treatment of coccidiosis induced by Eimeria species. Unfortunately, the toxic effects of ionophores cause concern because of their narrow safety margin. Ionophores’ toxicity could be probably due to oxidative damage. Therefore, it can be prevented by the supplementation of antioxidants in the diet. It has been reported that 60 or 120 mg/kg of salinomycin caused some pathological changes in the liver, heart, kidney, and muscles, such as degeneration or necrosis of these tissues. However, administration of salinomycin with vitamin E or selenium showed that vitamin E decreases the pathological changes.  The present study aimed to investigate the effects of salinomycin administration in combination with some natural antioxidants on reducing salinomycin toxicity in laying chickens.
A total number of 400 day-old hy-line w36 chicks were used in a completely randomized design with five treatments and four replications for 35 days. Treatments were included: 1) control diet, 2) negative control diet containing 0.05% salinomycin sodium, 3) negative control + garlic powder (15 g/kg of diet), 4) negative control + selenium (450 mg/kg of diet) + vitamin E (2 g/kg of diet), and 5) negative control + zinc-methionine (160 mg/kg of diet). Body weight gain, feed intake, and body weight uniformity were measured weekly. Blood samples were taken to evaluate the levels of antioxidant enzymes, liver enzymes, electrolytes, and malondialdehyde levels at the end of the experimental period.
The results showed that the salinomycin diet (T2) decreased body weight and feed intake compared with the control diet in the total experimental period (P<0.05). But the addition of supplemental Zn-methionine to the diet (T5) led to improved body weight and feed intake (P<0.05). Significant differences were observed among various treatments for the relative weight of visceral organs (liver, heart, kidney, gizzard, proventriculus, intestine, and bursa of Fabricius), but there were no significant differences for spleen and lungs. Also, salinomycin increased the activity of liver enzymes including alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), and serum malondialdehyde (MDA) in the negative control group and control group, and decreased the level of serum antioxidant enzymes compared to the control group (P<0.05), but the addition of vitamin E + selenium to the diet, eliminated the negative effects of salinomycin on these parameters (P<0.05). Vitamin E plays important roles in various biochemical and physiological processes, including antioxidation. The protective effect of vitamin E against the alterations induced by salinomycin on these estimated parameters in this study could be attributed to the role of vitamin E as a fat-soluble antioxidant, which protects the biological membranes from oxidative damage and decreases osmotic fragility of erythrocytes. Selenium also exerts its protective effect against oxidative damage by a decline in free radicals and increasing the synthesis of glutathione peroxidase, which catalyze the breakdown of toxic hydrogen peroxide and lipid hydroperoxides. Salinomycin decreased serum chlorine and increased serum potassium compared to the control group (P<0.05), and only the use of vitamin E + selenium adjusted these changes (P<0.05). The T2 group reduced the serum level of chlorine and increased the serum level of potassium (P<0.05). But there is no significant effect on the level of blood calcium. Although all treatments with antioxidants changed the levels of these electrolytes. The changes in electrolyte balance can result in metabolic alkalosis and acidosis. However, the T4 group only reduced the serum levels of potassium and calcium and increased the serum level of chlorine significantly, compared to the T2 group (P<0.05). However, there were no significant differences in the serum sodium and creatinine levels among various treatments.
Salinomycin administration in the diet of laying chicken induces undesirable effects on some estimated parameters probably due to oxidative damage. But, the supplementation of pullet diets with vitamin E and selenium can reduce the possible side effects of salinomycin.

 Zinc is part of more than 300 enzymes involved in immunity, metabolism, growth and reproductive functions. This element is essential for the metabolism of nucleic acids, proteins, carbohydrates, the development and proper functioning of immune cells. Therefore, zinc deficiency can affect the performance of animals by reducing appetite and growth and immune system disorders.Fat supplementation in milk replacer or starter diets has been suggested to improve the energy density of calf diets. Linoleic and alpha-linolenic are two essential fatty acids precursors of eicosanoids, important molecules in regulation of inflammation. Eicosanoids derived from linoleic acid has the inflammatory effects, while Eicosanoids derived from alpha-linolenic acid has anti-inflammatory effects. Adding alpha-linolenic acid in the form of Ca-salt of flaxseed oil to calf starter improves daily weight gain and feed efficiency. It seems to decreasing the ratio of linoleic acid to alpha linolenic acid in the diet have positive effects on the health and immune system of dairy calves.Zinc has a direct effect on modulating the activity of desaturase enzymes in fatty acid metabolism and also indirectly affects the absorption, oxidation and composition of fatty acids. In addition, zinc participates in the structure of superoxide dismutase, which is an important enzyme in the oxidative process of lipids. Free radicals reaching the cytoplasm are neutralized by this enzyme. The aim of this study was to evaluate the effect of organic supplementation of zinc and dietary Ca-salt of flaxseed oil on growth performance, health status and some blood parameters of Holstein calves.

A total of Twenty-eight 3-day-old female Holstein calves with a starting average weight of 35.7±2 kg were used based on a completely randomized design with a 2×2 factorial arrangement of treatments and 7 replications per treatment for 49 days (before weaning). The experimental treatments were: 1) Control (CON), 2) diet containing 0.1% Zn-methionine supplement (+Zn), 3) diet containing 2.5% Ca-salt of flaxseed oil supplement (+Fat) and 4) diet containing 2.5% Ca-salt of flaxseed oil supplement with 0.1% Zn-methionine supplement (+Fat +Zn). The calves were housed in individual pens and fed with whole milk and had free access to the feed starter and water. Milk was offered 4 L/d in two equal meals daily at 07:00 and 19:00. All the calves were weighed at the beginning of the experiment and days 14, 28, 42 and 49. Daily weight gain and feed efficiency (gain to feed) were calculated. Apparent digestibility was determined by the internal marker method of acid-insoluble ash. Changes in skeletal growth and health scores from birth to 42 days were recorded. Blood samples were collected from the jugular vein on last week of the trial (3 h after the morning feeding). Blood parameters data were analyzed using the PROC GLM procedure of SAS (9.1v). Repeated measured data (body weight, feed intake and feed efficiency) were analyzed using the PROC MIXED procedure and health scores were analyzed using a multivariable logistic mixed model (GLIMMIX). Significance among treatments was determined by the Tukey test and results were considered as significant the P-value was less than 0.05.

 This study results showed that the use of Zn-methionine and Ca-salt of flaxseed oil had no significant effect on dry matter intake and growth performance. Daily weight gain tended to increase from day 29 to day 49 in treatments containing fat supplement. Fat supplementation increased dry matter and organic matter apparent digestibility. Addition of zinc-methionine supplement to diets had no effect on apparent nutrient digestibility. Skeletal growth indices did not affect by dietary treatments. Attitude score, nasal discharge, days with fever, days with diarrhea and days with poor attitude were not affected by experimental treatments. Ca-salt of flaxseed oil reduced rectal temperature and improved fecal consistency. Organic Zn did not improve calf health status. Decreased rectal temperature as a result of consuming the source of alpha-linolenic acid may be due to the effects of alpha-linolenic acid and its derivatives eicosanoids in reducing the incidence of inflammatory responses. Interaction among fat and Zn-methionine tended to affect alanine aminotransferase enzyme concentration. Zn-methionine supplement increased the concentration of alkaline phosphatase. Alkaline phosphatase has four Zn element in its active site. This enzyme is involved in calcium absorption and animal growth and is considered as indicator of Zn status. The increase in alkaline phosphatase concentration in the present study can be attributed to the increase in zinc uptake from the source of the organic zinc-methionine.

 It seems that feeding of Ca-salt of flaxseed oil with high levels of unsaturated fatty acids in dairy calves have a positive effect on calf health status and apparent feed digestibility.

In this experiment, nano DL-methionine was synthesized from commercial DL-methionine and used in broiler diets to evaluate the effects on growth performance, carcass characteristics, blood parameters and small intestine morphology. A total of 200 one-day-old broilers (Arian) were used in a completely randomized design with five treatments and four 4 replicates of 10 birds for a period of 40 days. Experimental treatments included: 1) a control diet consisted of DL-methionine, 2) a diet included 75% of DLM of the control+2.5% nano-methionine, 3) a diet included 50% of DLM of the control+5% nano-methionine, 4- a diet included 25% of DLM of the control+7.5% nano-methionine, and 5- a diet included 10% nano-methionine. The results showed that replacing DLM with NM caused no significant difference between treatments for live responses, carcass characteristics and activities of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase. There was no significant difference between treatments for serum uric acid, height and width of villi in duodenum and jejunum. However, groups with 7.5% and 10% NM manifested a significant increase (P < 0.05) in breast weight and villus height and width and its absorptive surface area compared to the control. In conclusion, the use of NM could save up to 90% of DLM requirements.

This study was conducted to evaluate the effects of particle size of chromium-methionine (Cr-Met) on growth performance, carcass traits and meat quality of broiler chicks under physiological stress conditions. A total of 288 broiler chicks (male) were used in a 2 × 3 factorial arrangment with two stress status (no stress, stress) and three levels of Cr-Met (no Additive, 2000 ppb of Cr-Met, and 2000 ppb of Cr-Met milled) in a completely randomized design with six treatments, four replicates and 12 birds per each pen. Dexamethasone was added to diets (1.5 mg/kg diet) for a week (18-24 d) to induce physiological stress. Feed intake and body weight were measured weekly and feed conversion ratio was calculated. The malondialdehyde content and the water holding capacity of meat were measured at 24 and 46 d of age. Also, breast meat pH was measured at 46 d. Physiological stress decreased feed intake, weight gain, carcass yeild, relative weight of spleen, bursa, heart and liver, but increased FCR and water holding capacity of meat bereast (P<0.05). In stressed birds, both forms of dietary Cr- Met improved FCR and increased the meat pH (P<0.05). There were no differences between the effects of particle size of Cr-Met on the studied parameters. According to the results of this experiment, dietary supplementation of 2000 ppb Cr-Met in different sizes reduced the negative effects of physiological stress and improved the FCR and carcass yield of birds under physiological stress.

Chromium (Cr) plays an important role in ruminant’s metabolism. Situations such as accelerating growth, stress and low bioavailability of Cr in feedstuffs, result in depletion of chromium stores of body, therefore, metabolic disorders and growth retardation occurs. Chromium is an essential element for animals and humans It functions as cofactor for insulin and it is assumed to be essential for activation of certain enzymes and stabilization of proteins and nucleic acids Therefore, impaired carbohydrate and protein metabolism, decreased insulin sensitivity in peripheral tissues and thereby decreased weight gain would be expected in Cr-deficient individuals especially under stressful conditions. Chromium improves health by reducing free radicals and also stimulates the immune system and makes the body more resistant to diseases during stress by lowering blood cortisol levels. The aim of this study was to investigate the Effects of chromium-methionine on growth performance, blood parameters and health of Holstein suckling calves under heat stress.

For this experiment, 30 newly-born Holstein calves (average age 1-8 days), average weight 39±1 kg) were used in a completely randomized arrangement with 2 treatments and 15 replications. The experimental treatments were: 1) Basal diet without any additive (control), 2) Basal diet with 0.05mg of chromium-methionine. Daily feed intake were recorded daily and body weight were recorded at birth days, 30, 60 and 65 breeding periods and feed conversion ratio was calculated for each group. The average maximum temperature–humidity index was 91.2 U, indicating severe environmental heat load.

The results showed that the use of chromium methionine supplementation in calves under heat stress had not a significant effect on feed intake, final weight, daily weight gain, feed conversion ratio and skeletal growth during the first, second and entire breeding months. The blood concentration of glutathione peroxidase was affected by chromium methionine supplementation, while the blood concentration of glutathione in calves receiving chromium supplementation was 57.78 versus 47.19 u/g (P <0.04). Respiration rate, breaths/min and heart rate in calves receiving chromium were low, so that numerically the number of breaths and heart rate in chromium-methionine-supplemented calves was 50.50 versus 54.40 per minute and 10 / 98 were in front of 10/50 times. Rectal temperature and fecal score were not affected by chromium intake in calves.

Results of this experiments showed that the use of chromium methionine in suckling calves improved glutathione peroxidase concentration, fecal score and rectal temperature but had no effect on growth performance and skeletal size

An experiment was conducted to determine the effect of in ovo injection (IOI) of different sources of organic and inorganic of zinc on post-hatch parameters, bone characteristics, and broiler chickens performance. Fertile eggs (n=480) were weighted, distributed into 6 groups of 80 eggs in force-draft incubator. On 17th days of incubation, 2 groups were injected with 0.5 ml of 80 or 100 µg zincsulfate dissolved in physiology serum. Other 2 groups were injected with 0.5 ml of 80 or 100 µg methionine-zinc dissolved in physiology serum. Rests two groups were used as sham control (injected with 0.5 ml physiology serum) and un-injected control. After hatching, hatched chickens (2 chickens per each replicate) were randomly selected and parameters were measured. The results showed no significant differences were in the hatched chick’s weight. The highest percentage of hatching was related to IOI 100 µg methionine-zinc and 80 µg mg zincsulfate (p < 0.05). In addition, the IOI of organic and inorganic source of zinc increased tibia zinc (p < 0.05).The IOI 80 µg of zinc-methionine increased tibia weight (P <0.05) The IOI 80 or 100 µg zinc-methionine increase the tibia zinc content at 21 days of age (P <0.05). Also, tibia length increased with IOI 100 µg zincsulfate and IOI 80 µg zinc-methionine compared to other treatments (P <0.05). There was no difference in the apparent ileal digestibility of zinc and performance (feed intake, weight gain, and feed conversion ratio) in response to IOI different levels of organic and inorganic sources of zinc.

In order to study theeffects of various levels of organic chromium on performanceand egg quality characteristics oflaying hens reared at high stock density, an experiment was done using twolevels of density (three and five birds per cage) and four levels of organic chromium (0, 300, 600and 900 ppb) with 192 laying hens (Hy-line W-36) in a completely randomizeddesign with factorial arrangement of 4×2 with six replicates. The results showed that dietarysupplementation of chromium at normal and high stock density had notsignificant effect on performance of layers. Egg weight significantly increasedat levels of 600 and 900 ppb (56.96 and 56.91 g) and feed intake significantlydecreased (99.34 vs. 105.05) in birds reared at high stock densitycompared to the birds reared at normal stock density (P<0.05). In thefirst four, second, and whole periods of sampling, dietary inclusion ofchromium at normal and high stock density, increased significantly egg yolkcolor and egg shell strength compared to the control (P<0.05). Dietarysupplementation of chromium at normal and high stock density had notsignificant effect on blood parameters and tibia charachteristics of layers. Ingeneral, the results of the experiment showed that by increasing dietarysupplementation of chromium at high stock density up to 900 ppb, egg yolk colorand egg shell strength significantly increased in laying hens.

The role of trace minerals in animal production is an area of strong interest for producers, feed manufactures, veterinarians and scientists. Zn (Zn) is one of the most important elements that has been recognized as a essential catalytic factor for more than 300 enzymes enzyme. Zinc also has an essential role in metabolism of nucleic acids, proteins, lipids, and carbohydrates. The National Research Council (1985 and 2007) recommended about 30 mg/kg zinc for ewes and growing lambs. However, the soil status and zinc concentration in native plants are also affected. In many regions of Iran, the Zn content of soil and plants is commonly low (less than 0.8 mg/kg). As a result, health and performance of animals reared on mainly homegrown roughage and grains may be affected as a consequence of nutritional deficiency. Recently, the use of organic sources of mineral supplements (complexes, chelates and proteinates) has increased. However, the results of organic and inorganic sources in ruminants are contradictory. Furthermore, few studies have investigated the effect of zinc on lipid parameters in ruminants. Therefore, the aim of the present study was to compare the effect of supplementation of 30 mg/kg Zn from the three organic sources and conventional inorganic source on performance, hematological parameters and mineral profile of Mehraban growing lambs.

 Thirty male lambs with 4-5 months of age and 30.8±2.8 kg average in weight randomly allotted to 5 groups. Treatments were: 1) Basal diet without zinc supplement (containing 19.72 mg/kg DM zinc); 2) Basal diet+30 mg/kg DM zinc as zinc methionine; 3) Basal diet +30 mg/kg DM zinc as zinc proteinate; 4) Basal diet +30 mg/kg DM zinc as zinc glycinate, and 5) Basal diet +30 mg/kg DM zinc as zinc sulfate. This trial lasted for 70 days. The dry matter intake, daily gain and feed conversion ratio were determined. Blood samples were taken on days 0, 35 and 70 before the morning meal. Chemical composition of experimental samples including (crude protein, neutral detergent fiber, acid detergent fiber, and dry matter) and blood parameters including (hematological, mineral and lipid profiles) were measured according to standard methods. This experiment was analyzed in a completely randomized design.

Average daily gain and dry matter intake for all groups fed the supplement were significantly higher than control group and feed conversion ratio also improved (p

Zinc has a role in many cases such as rumen microbial activity, immunity, and blood metabolites. But, there is no sufficient information on the effect of nano and organic Zn supplements on microbial protein synthesis and immunity variables in Holstein calves. Thus, this study was conducted to assess the effect of using nano-ZnO and Zn-methionine instead of ZnO (equal to or twice NRC 2001-recommended level) on urinary purine derivatives, microbial protein, immunoglobulins and nitrogenous compounds of the blood in pre- and post-weaning calves.

Sixty suckling Holstein calves were assigned into one of the 6 experimental groups (10 replications) in a completely randomized design. The experimental treatments were the diets containing: 1- ZnO equal to NRC recommendation, 2- Zn-methionine equal to NRC recommendation, 3- nano-ZnO equal to NRC recommendation, 4- ZnO twice NRC recommendation, 5- Zn-methionine twice NRC recommendation, and 6- nano-ZnO twice NRC recommendation. During 7 to 30 days of age, the calves were fed with milk and starter concentrate according to the above treatments. From days 31 to 70, milk and mixed alfalfa-starter (at the ratio of 10:90) were provided for the calves. Weaning was done at 70 days of age and during post-weaning period (71 to 100 days of age), the calves were freely fed with experimental diets (alfalfa and starter concentrate at the ratio of 20:80). During pre- and post-weaning periods, the urinary purine derivatives, microbial N synthesis, total globulin, IgM, IgG, total protein, albumin, urea-N, creatinine and glucose of the blood were determined. Data were analyzed in a factorial experiment (3×2) using PROC MIXED of SAS (2001).

Urinary purine derivatives and microbial N synthesis were not affected by replacing ZnO with nano-ZnO and Zn-methionine during pre- and post-weaning periods. Zinc chemical form had no significant effect on the blood concentrations of total globulin, IgM and IgA. Total protein, albumin, urea-N, creatinine and glucose in the blood of the calves fed with inorganic, nano or organic Zn supplements were the same. Moreover, increasing Zn level in the diet had no effect on urinary purine derivatives, microbial N synthesis, total globulin, IgM, IgA, total protein, urea-N, creatinine and glucose.

Using nano-ZnO and Zn-methionine instead of ZnO and also the increasing dietary Zn level had no effect on microbial protein synthesis, IgM, IgA, nitrogenous compounds and glucose in the blood of the calves. Thus, feeding the conventional inorganic Zn source (ZnO) at the NRC-recommended level was sufficient to supply the calves’ requirement during pre- and post-weaning periods and the other sources are not recommended.

 Selenium (Se), as an antioxidant element, is a neutralizing mineral for oxidative stress and urging apoptosis in stressed biological systems. Selenium is a necessary trace element for ruminants that participates in varied biological processes like antioxidant defense, production of thyroid hormone, and response of immune system. In recent years, researches have focused on the best supplementary sources of selenium to maximize biological performance. The studies about reproductive performance, such as that of Gabryszuk and Klewiec (2002), showed that injecting ewes with Se four weeks before breeding and again during the last four weeks of gestation caused a 32% increase in lambing percentage compared with Se-deficient ewes. Furthermore, adequate Se status of the newborn lambs not only ensures prevention of nutritional myopathy, but also decreases losses in lamb productivity. Lambs from Se-supplemented ewes showed faster progression to stand and nurse compared with lambs from unsupplemented ewes and leading to an overall decrease in lamb mortality (Muñoz et al. 2009). It has been observed that selenium mineral supplements, such as sodium selenite and sodium selenate, have the same bioavailability. However, organic selenium supplements such as yeast selenium more effectively increase the concentration of selenium in blood and milk and may have a better bioavailability. However, the recently developed red elemental selenium has promising uses in the environmental protection from the pollution of the excessive selenium (Zhang et al. 2007). Zhang et al. (2007) synthesized nano red elemental selenium (nano-Se) with the size of 5 – 100 nm and observed that nano-Se had a similar bioavailability in rat and much less acute toxicity in mice compared with selenite. Recently, Wang et al. (2007) showed that nano-Se (20 – 60 nm) possesses equal efficacy in increasing the activities of GSH-Px in plasma and liver from male Kunming mice compared with selenomethionine. The periparturient period is the foremost necessary stage in farm animals about health standing and production. The objective of this study was to determine the effect of different sources of selenium on blood and serum selenium concentration of Khalkhali goats during late pregnancy, as well as the effect of these sources on the concentration of selenium in their kids up to four weeks and serum and colostrum immunoglobulin concentration (IgG) of mothers and kids (immediately after birth).

The experiment was conducted using 40 Khalkhali goats in a completely randomized design devided into four groups with 10 goats per each group. The goats were randomly allocated to four treatments to receive supplementations of 0 (control), 0.6 mg Se head−1</sup> day−1</sup> of seleno-methionine (SM), 0.6 mg Se head−1</sup> day−1</sup> of nano-selenium (SN), and 0.6 mg Se head−1</sup> day−1</sup> of sodium selenite (SS) from four weeks before the expected day of delivery. Their blood samples were taken at that time and on the kidding day. In addition, colostrums were collected in pre-cleaned polyethylene bottles from the goats as immediately as possible after kidding. Instantly after delivery, newborn kids were taken apart from their dams. The control group did not receive any supplement and received only the basal ration containing 0.1 mg Se kg-1</sup> DM. Blood samples were collected from goats three weeks before the expected kidding. Blood samples of kids were taken from the jugular vein on the day of birth and 7 days after birth. Blood samples were centrifuged at 3000 rpm for 15 minutes to prepare the serum. The ELISA method was used to determine the concentration of IgG and selenium concentration was measured using the ICP-OES device. The weight of kids at the birth and up to four weeks, colostrum production in the first three days and milk production of goats for four weeks were recorded and analyzed.

 There were no significant differences in birth weight, weight of kids up to four weeks, colostrum production in the first three days, and milk production until the fourth week in goats. There was a significant difference between the groups in serum IgG concentration, colostrum IgG, and blood IgG concentration of kids (P<0.05). No significant differences were observed between mineral selenium, nano-selenium, and control group. However, seleno-methionine had a significantly better performance than nano-selenium and sodium selenite. Serum and blood selenium concentrations were similar before kiding, but the concentration of selenium in serum and blood of supplemented goats was significantly higher than the control ones (P> 0.05). The results of this experiment showed that serum and blood selenium concentrations in nano-selenium recieved goats were significantly higher compared with other groups (P<0.05). Serum and blood selenium concentrations of kids at birth and colostral selenium concentration in the experimental groups were significantly higher than the control group (P <0.05), except for the goats supplemented with selenium nanoparticles, which significantly decreased compared to the control goats. The serum selenium and blood levels of selenomethionine recieved group showed the highest selenium levels in comparison with other groups. Selenium blood levels increased significantly in the first week of life of the kids only in the organic supplementation treatment (P <0.05).

Organic selenium supplementation in late pregnancy was effective in transferring blood immunity from the goats to the kids and led to changes in serum and colostrum IgG levels of goats. The supplementation of different Se forms (sodium selenite, selenomethionine and elemental nano-Se) into pregnant goats’ diet increased Se status in the whole blood and serum compared with controls. Among Se sources, nano-selenium exhibited an excellent increasing Se status in pregnant goats. Current results showed differences in the transplacental Se transfer capacities of sodium selenite, selenium nanoparticles, and selenomethionine. When comparing these three Se sources, the results of the study clearly demonstrated that kids from goats receiving selenomethionine had higher whole-blood and serum-Se concentrations compared with kids from goats receiving sodium selenite and selenium nanoparticles. There was a failure of nano-selenium to increase newborn Se concentrations as compared with control. Seleno-methionine had higher transplacental transfer of Se and also resulted in higher Se concentrations in colostrum. Goats supplemented with seleno-methionine had greater colostral Se concentrations than goats supplemented with sodium selenite and selenium nanoparticles.

In ovo feeding is considered as a useful tool to overcome the growth limitations during embryonic growth and after hatching in domesticated poultry. Therefore, the purpose of the present study was to investigate the effect of different levels of DL- methionine on the morphology of small intestine in ROSS 308 broiler chicks. In this regard, the total number of 240 eggs from Ross 308 broiler breeder were used according to a completely randomized design (CRD) with 8 experimental groups and 30 eggs per each treatment. The experimental treatments included different levels of DL-methionine amino acid (0.19, 0.38, 0.57, 0.76, 0.95 and 1.14 %), along with a sham-control group (sterile water injection) and a control group (without injection) which were injected into the amniotic fluid on the 14th d of incubation. After hatching, the chicks were weighed and slaughtered to measure small intestine morphological characteristics. Results of the study indicated that in ovo feeding of DL-methionine had a significant effect (p<0.05) on hatchability, weight and relative weight of jejunum, small intestine weight, as well as crypt diameter (except for duodenum), villus height, crypt depth, villus height to crypt depth ratio, and villus thickness in duodenum, jejunum, and ileum. On the other hand, no effect of treatments (p>0.05) was observed on chick weight and weight and length indexes of duodenum and ileum. Based on the results of this study, the best morphological response was observed in 76% DL-methionine treatment.

In the present study, fifteen Kermani male lambs with average body weight of 31.9±1.2 kg were used in a completely randomized design with 3 treatments and 5 replicates each, for 10 weeks including 2 weeks of adaptation to basal diet and 8 weeks of data collection. The experimental groups were (1) control group (without chromium-methionine (Cr-Met) supplementation), (2) lambs fed with 1.5 mg Cr/kg diet of Cr-Met, and (3) lambs received 3 mg Cr/kg of Cr-Met supplement. The results showed that average daily feed intake of lambs received 1.5 (p=0.002) and 3 (p =0.0004) mg/kg of Cr supplement was higher than that of the control animals. Chromium supplement had no influence on final body weight and average daily gain, however, feed conversion ratio decreased in lambs fed with 3 mg/kg diet of Cr supplement (p=0.04). The digestibility coefficients of dry matter, organic matter, fat and neutral detergent fibre (NDF) were not affected by the experimental treatments; however, acid detergent fibre (ADF) digestibility was higher in lambs fed with 1.5 (p=0.003) and 3 (p=0.02) mg Cr/kg of diet than those fed the control diet. Chromium supplement had no significant effects on pH and ammonia nitrogen (NH3-N) concentration of ruminal fluid. Similarly, serum glucose, total protein, albumin, globulin, triglyceride and urea concentrations were not different among experimental groups. It can be concluded that feeding 3 mg/kg diet of Cr-Met supplement improves feed conversion efficiency of fattening lambs. Moreover, both Cr-Met levels decrease feed intake and increase ADF digestibility.

The aim of this study was to determine the effects of Zn-methionine (Zn-Met) and Zinc sulfate (ZnSo4) supplementation on growth performance, carcass characteristics, serum zinc and copper and zinc concentrations in some tissue i.e. length, weight, internal and external offal items in Sanjabi lambs. All lambs were slaughtered at end of fattening period and biometry of carcass was determined, also zinc concentration in five carcass tissues were analyzed. The results showed that ZnSo4 supplementation reduced dry matter intake, final body weight, carcass weight without fat-tail and carcass length as compared to the control group (P<0.05). The hind leg and fore leg length increased in the Zn-Met group (p=0.001). The Zn concentration of Quadriceps femoris and Longissimus dorsi were not significantly affected by organic and inorganic Zn supplementations, however, pancreas, lounges and heart concentrations of Zn were higher (P<0.01) in organic Zn groups as compared to other groups. The Zn concentration of feces showed that zinc sulfate bioavailability was lower compared to the Zn-Met group (p=0.001). The concentrations of Zn and Cu of serum were not affected by Zn supplementation in treated lambs (P> 0.05). The result of this study showed that zinc sulfate supplementation reduced lams growth and DMI, however feed efficiency ratio was not affect by treatments. The Zn-Met was not affected on growth of lamb, however the lounges and heart Zn concentrations increased.

In this study, the effect of different levels of ZnO, nano-ZnO and Zn-methionine, in pre- and post-partum diets, on feed intake, Zn absorption, microbial protein, as well as metabolites and IgG, IgM and IgA in the blood and colostrum of ewes and suckling lambs were investigated. Experiment was conducted from 50 days before to 30 days after lambing. Sixty pregnant Khorasan-Kurdish ewes were divided into six experimental groups (10 replicates) in a randomized complete block design. Experimental diets contained ZnO, nano-ZnO and Zn-methionine to meet NRC recommendation, or higher than NRC-recommended level. Replacing ZnO with nano-ZnO or Zn-methionine had no effect on different variables in ewes, but increasing Zn level in the diet of ewes resulted in an increment of daily Zn intake, a decline of Zn absorption coefficient and an increase of fecal Zn excretion (P<0.05). Feeding mother ewes with different Zn sources had no effect on blood metabolites and immunoglobulins of the suckling lambs. Overall, nano-ZnO had no positive or negative effects on ewes and suckling lambs and using Zn-methionine instead of ZnO did not improve the metabolic condition of the animals. On the other hand, the increasing dietary Zn concentration increased zinc excretion in the environment. In practice, using the conventional ZnO at the NRC recommendation level is sufficient to provide the requirement, and to maintain the immunity of pre- and post-partum ewes and there is no need for additional Zn from other sources.

In order to investigate the effects of in ovo injection of different sources of manganese on performance and tibia characteristics of broilers, a total of 480 fertile eggs from ROSS 308 were assigned to 6 treatments, 4 replicates of 20 eggs per replicate in a completely randomized design. The experimental treatments included non-injected (negative control, NC), injection of1 ml serum physiology(positive control, PC), 1 ml of manganese sulfate (MnS), 1 ml of manganese- methionine (MnM), 1 ml of nano manganese (NMn) and 1 ml of nano manganese methionine (NMnM). The results showed that the in ovo injection of different sources of manganese lead to improvement in broilers growth. The highest and lowest body weight gain in entire production period were recorded for NMn and PC group, respectively (P<0.05). NMn and NMnM groups showed the best feed conversion ratio in whole experimental period (P<0.05). The tibia length at 21 day of age was significantly higher in treatment containing MnS and fresh and dry weights of tibia at 21 and 42 days of age were significantly increased with NMn (P<0.05). The tibia breaking strength at 21 and 42 days of age was significantly increased in treatments containing NMnM and NMn (P<0.05). The tibia volume, density and ash percentage were not affected by experimental treatments on 21 and 42 days of age (P>0.05). According to these results, it seems that the in ovo injection of manganese nanoparticles as a feed additive has positive effects on performance and tibia characteristics of broilers.