selenium

The aim of this study was to investigate the effect of feeding top dress Hydroxy Seleno Methionine (HSM) as organic Selenium and cotton seed bioactive peptide (CSBP) on body condition, health of the reproductive system and subsequent pregnancy of dairy cows. For this purpose, one hundred and eighty multiparous Holstein cows at the day 21 prior to the expected calving date were assigned to one of four experimental treatments in a randomized complete block design in a 2x2 factorial arrangement: 1) Basal diet (containing mineral selenium as per NRC (2001) recommendations without peptide; 2) Basal diet plus 300 g bioactive peptide; 3) Basal diet plus 1.2 mg organic selenium per kg of dry matter without bioactive peptides; 4) Basal diet plus 1.2 mg organic selenium per kg of dry matter plus 300 grams of bioactive peptide. The inclusion of HSM during the prepartum period resulted in a higher BCS in postpartum and smaller increase in BCS during prepartumd (P < 0.01). Additionally, there was a significant interaction effect between HSM and CSBP on BCS (P < 0.02) and its changes (P < 0.01) during the post-partum periods. The presence of ovarian cysts, number of inseminations per pregnancy, the endometrium and uterine regression scores and pregnancy during the first insemination was not influenced by any of the experimental treatments (P > 0.1). However, HSM had a positive effect on pregnancy during the second insemination (P < 0.05). It can be concluded that supplementing HSM could reduce the BCS changes before and after parturition and  subsequent to that, it leads to an enhancement in the pregnancy during the second insemination.

Iodine is a structural component of thyroid hormones (T3 and T4), which are essential for the life of mammals. Iodine deficiency leads to insufficient production of thyroid hormones, which is primarily due to the lack of iodine in the soil. Selenium is also involved in the metabolism of thyroid hormones by participating in the construction of selenoproteins that convert the inactive form of T4 into the active form of T3. The aim of this study was to investigate the effects of iodine supplementation on thyroid hormone concentrations of in ewes exposed to iodine deficiency under selenium deficient or sufficient conditions.

A flock of sheep was selected in an area where selenium and iodine deficiency had been identified. In this flock, 30 young ewes (2-3 births) of Farahani breed with similar body weight (47 ± 6 kg) were randomly divided into three groups, including a control group and two experimental groups. The first and second experimental groups received 390 mg of iodine in the form of fatty acid ethyl ester from safflower oil at the end of gestation at the end of winter season, and the second experimental group received 10 ml of selenium supplement in the form of subcutaneous injection. The concentration of thyroid hormones, including triiodothyronine and thyroxine, inorganic iodine in serum and selenium concentration in blood serum were measured and compared before the beginning of the experiment and monthly until the third month in the experimental groups.

The inorganic iodine concentration in the serum of the experimental animals at the beginning of the experiment was 15.53 μg /L and the selenium concentration in the blood serum was 79.73 ng/ml, both of which were in the deficiency range. Iodine supplementation caused a significant increase in the concentration of inorganic iodine in blood serum in the experimental groups compared to the control group in all three months of sampling (P < 0.01). Selenium supplementation also caused a significant increase in blood serum selenium concentration in the selenium+ iodine-supplemented group compared with baseline and the control and iodine supplemented groups in all months of the experiment (P < 0.01). In the first experimental month after iodine supplementation, an increase in T4 hormone concentration was observed in the iodine-supplemented group and in the iodine + selenium supplemented group compared with baseline and the control group. The concentration of T4 hormone was higher in the iodine supplementation group than in the control group and in the iodine + selenium supplementation group in the second and third months. Iodine supplementation increased T3 concentration in the first and second months of the trial compared with baseline, and selenium supplementation also significantly increased T3 concentration in the first and second months of the trial in the iodine + selenium supplemented group compared with the iodine supplemented group and the control group. The increase in the concentration of thyroid hormones after iodine supplementation showed that the production of these hormones was affected by iodine deficiency. Selenium supplementation increased the concentration of T3 in the first and second months and decreased the ratio of T4 to T3 in the second month. It showed that the effect of iodine supplementation is better in the conditions of selenium sufficiency.

The results indicate the effect of iodine supplementation to increase inorganic iodine concentration in serum, and the increase in thyroid hormone concentration after iodine supplementation indicates the limiting effect of iodine deficiency on the production of these hormones under iodine deficiency conditions. In selenium deficiency, the effect of iodine supplementation on T3 hormone production may be limited.

In this research, the effect of zinc and selenium synthesized from nano-mineralized probiotics was investigated on yield characteristics, egg quality characteristics, antioxidant status, and immune response of laying hens. A number of 576 high-line laying hens at the peak of production (from 25 to 37 weeks of age in three four-week periods) were used as a completely randomized design with a 3x3 factorial experiment with eight replications and eight birds per replication. Experimental treatments are 1. The control diet (without selenium and zinc), 2. Control diet + selenium chelate, 3. Control diet + zinc chelate, 4. Control diet + zinc synthesized from probiotics, 5. Control diet + selenium synthesized from probiotics, 6. Control diet + zinc chelate + selenium chelate, 7. Diet Control + zinc chelate + selenium synthesized from probiotic, 8. Control diet + zinc synthesized from probiotic + selenium chelate, 9. Control diet + zinc synthesized from probiotic + selenium synthesized from probiotic. The results showed that using zinc and selenium synthesized from probiotics increased production percentage, average egg weight, and improved feed conversion ratio (P<0.05). The serum concentration of cholesterol, triglyceride and malondialdehyde in chickens receiving probiotic zinc and selenium was the lowest. The serum HDL concentration and total antioxidant index were the highest compared to other treatments (P<0.05). In general conclusion, zinc and selenium synthesized from nano-mineralized probiotics have a better performance in laying hens.

Soybean meal (SBM) is the main protein source in diets for poultry due to its high protein and excellent amino acid quality and profile, in addition to its high availability of amino acids. However, in some countries, other protein sources are available at lower prices and can be included in least-cost formulations instead of SBM. Rapeseed meal (RM) is the second most important oil-producing crop after soybean. Recently, there has been increasing interest in rapeseed production in countries around the world including Iran. Although RM has a good amino acid profile, its crude protein content (36% to 39%) is lower than that of SBM (44% to 48%). Despite higher levels of methionine and cysteine in RM, its lysine content is lower than SBM. The use of RM has been limited by its low available protein and energy contents relative to SBM. The main factor affecting the levels of available crude protein and energy content is the fibrous hull of RM. RM also contains non-starch polysaccharides and glucosinolates. Excessive levels of RM and thus high dietary glucosinolate content could lead to abnormalities in thyroid function activities and consequently a retardation in growth performance. Therefore, the objectives of the current study were to determine the effects of dietary selenium (Se) and levothyroxine (LT) supplementation on performance, carcass characteristics, and thyroid hormone concentration in broiler chickens fed diets containing RM.
This experiment was performed to evaluate the effect of dietary Se and LT supplementation on performance, carcass characteristics, weight of internal organs, and thyroid hormone concentration in broiler chickens of commercial strain Ross 308. The experimental treatments were: 1) diet based on SBM and corn grain (positive control), 2) diet with 10% RM (negative control 1, NG1), 3) diet with 20% RM (negative control 2, NG2), 4) NG1+ 0.3 mg Se/kg diet, 5) NG2+ 0.3 mg Se/kg diet, 6) NG1+ 80 µg LT/kg diet, 7) NG2+ 80 µg LT/kg diet, 8) NG1+ 0.3 mg Se and 80 µg LT/kg diet, and 9) NG2+ 0.3 mg Se and 80 µg LT/kg diet. Nine dietary treatments with four replications and 15 chickens in each replication were allocated to the experimental pens in a completely randomized design. During the experimental period (1 to 42 days), average feed intake, body weight gain, and feed conversion ratio were measured. At day 38, two birds from each pen were selected and blood was taken from their axillary vein for measuring thyroid hormones. At the end of the experiment (day 42), two birds from each replicate were selected, weighed, and slaughtered for carcass and internal organs weight determination.
The results showed that there were no significant differences between the treatments receiving RM and the positive control treatment in terms of growth performance. The percentage of abdominal fat and the relative weight of the internal organs, except the gizzard, were not significant between the dietary treatments. The treatment of 10% RM supplemented with Se and LT had the highest relative weight of the thymus. The treatment with 20% RM had the highest and the treatment with 10% RM + LT and 10% RM + LT and SE had the lowest relative weight of bursa Fabricius. The relative weight of the spleen was not affected by the experimental treatments. The treatment containing 20% RM showed the lowest carcass weight and the positive control treatment had the highest percentage of breast muscle. The use of RM at 20% caused a significant increase in thyroid weight compared to the positive control group (group without RM). The thyroid weight was reduced by SE and LT supplementation to diets containing RM. Rapeseed meal had no significant effect on T4 hormone levels, but treatments supplemented with SE increased and treatments supplemented with LT decreased T3 hormone levels. Also, the level of TSH hormone in the treatments receiving RM was lower than that in the treatments without RM. Chickens receiving RM with SE and LT had the highest levels of antioxidant enzymes of glutathione peroxidase and superoxide dismutase.
According to the results of the present experiment, supplementing RM with SE and LT decreased the weight of the thyroid gland and increased the level of antioxidant enzymes, which suggests the positive effects of the use of these compounds in the diet based on RM on the function of the thyroid gland.

In mammals, the need for minerals increases during the pregnancy period for the growth and development of the fetus and reaches to its maximum level at the end of the pregnancy period. Therefore, it is vital to supplement pregnant ewes with sufficient quantity of micro-minerals to preserve the fetus and improve the growth of the newborn lambs. Selenium and cobalt are two essential elements for ruminants, which play a major role in animal performance. Selenium is necessary to maintain the normal physiological functions of the body, it also plays an important role in the production of thyroid hormones and the conversion of thyroxine to triiodothyronine. Cobalt is one of the essential elements that presents in the structure of vitamin B12. Therefore, the present study aimed to investigate the effects of using slow-release bolus of selenium and cobalt on milk production and composition, reproductive performance and some blood parameters of Lori Bakhtiari's ewes.

One hundred Lori-Bakhtiari ewes with an average age of three to four years and an average weight of 47.55 ± 5.44 kg were used in a completely randomized design. Experimental treatments included: 1) control ewes without receiving slow-release bolus, 2) ewes receiving slow-release selenium bolus with a release rate of 0.3 mg per day, 3) ewes receiving slow-release cobalt bolus with a release rate of 0.3 mg per day and 4) the ewes receiving slow release bolus containing selenium and cobalt with a release rate of 0.3 mg of selenium and cobalt per day. Blood samples were collected at 76 days post-breeding (mid-gestation) and 30 days postpartum from all ewes, and analyzed for serum concentrations of selenium, zinc, iron, triiodothyronine, thyroxine and creatine-phospho-kinase activity. The number and percentage of pregnant ewes, number and percentage of healthy lambs born, number and percentage of twining, number and percentage of lambs with white muscle disease and number and percentage of lambs survived after 70 d were also recorded.

Supplementing ewes with slow-release boluses of selenium and cobalt had no effect on the number of pregnant ewes, lambs born healthy, twins, lambs with clinical symptoms of white muscle and the number of live lambs up to the age of 70 days (P<0.05). Milk production was higher in ewes receiving slow-release cobalt and selenium-cobalt tablets compared to other treatments (P<0.05). Milk fat percentage in the ewes receiving slow-release cobalt and selenium-cobalt bolus was significantly lower than other treatments (P<0.05). The percentage of milk protein in the treatment receiving slow-release selenium-cobalt bolus was significantly higher than the control treatment (P<0.05), but there was no significant difference with the other treatments (P<0.05). Serum concentration of selenium in ewes receiving slow-release selenium and selenium-cobalt boluses was significantly higher than other treatments (P<0.05). Serum concentrations of zinc, iron and serum creatine phosphokinase activity were not affected by the experimental treatments (P<0.05). Serum concentration of vitamin B12 in ewes receiving slow-release cobalt and selenium-cobalt boluses was significantly higher than the other treatments (P<0.05). Serum concentrations of triiodothyronine and thyroxine were not affected by the experimental treatments, but the ratio of thyroxine to triiodothyronine was significantly lower in ewes receiving selenium and selenium-cobalt than the other ewes (P<0.05).

The results showed that supplementing ewes with slow-release boluses containing selenium and cobalt at the time of estrus synchronization increased serum concentrations of selenium and vitamin B12 before and after parturition, and increased milk production and milk protein content.

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.

To compare the effects of injection different levels of selenium and vitamin E in late pregnancy on thyroid hormone metabolism and biochemical parameters of Holstein cows and their calf performance, 28 pregnant Holstein cows were selected in 8 weeks before calving and randomly assigned to 4 treatments and 7 replications. Cows were then injected with selenium and vitamin E four and two weeks before the expected time for calving. Treatments included: injection of 0 (contro), 15, 30 and 45 ml of selenium and vitamin E supplements. Each ml of supplement contained 0.5 mg of selenium in the form of sodium selenite salt and 50 international units of vitamin E in the form of DL alpha tocopherol acetate. Cows were balanced in terms of age, weight and calving time. The results showed that injection of selenium and vitamin E in pregnant cows affected the weight performance of their calves (P<0.05) so that the daily weight gain and weight of calves at 30 and 45 days of age in Selenium and vitamin E treatments increased, compared to the control group (P<0.05). Receiving of selenium and vitamin E makes pregnant cows resistant to low blood glucose and triglycerides in the postpartum period. At one week after delivery. The concentration of glucose and blood triglycerides in the injected cows increased compare to the control treatment (P<0.05). Also, one week before and after delivery, with increasing the dose of selenium and vitamin E, the activity of glutathione peroxidase and the concentration of tetrahydrotyronine and triiodothyronine increased (P<0.05). In general, according to the present results, at least 30 ml of selenium and vitamin E at the end period of pregnancy for Holstein cows, could be recommended.

This experiment was conducted to evaluate the effects of supplementation of zinc and inorganic selenium in diets containing oxidized oil on performance, antioxidant enzymes activity, and meat quality of broiler chickens. A total of 480 day-old Ross 308 broiler chickens were randomly attributed into 12 treatments with four replicates each with 10 chickens in 2×3×2 factorial arrangement, includes: The thigh was dissected and muscles were removed to assess the malondialdehyde (MDA) content. The results showed that the birds’ average daily FI and FCR were not significantly influenced by dietary treatments. Inversely, the average daily BWG showed a significant difference among treatments over the experimental period (P <0.05). The birds received dietary Zinc at the level of 100 mg showed a higher activity of SOD enzyme (P <0.05). The lowest amounts of GPX was observed in birds fed diets containing oxidized oils, no dietary zinc and selenium at the level of 3.0 mg/kg. The highest and lowest levels of thigh meat MDA levels were noted in birds received diets containing oxidized oil with no dietary zinc and those had given fresh oil diets with supplementary zinc at 100 mg kg zinc and supplementary Se at 0.3 mg/kg, respectively. The results of this study revealed no synergistic effects between zinc and selenium on oxidative enzymes and MDA levels. It is recommended to supplement 100 mg / kg of zinc and 0.3 mg / kg of selenium to reduce the peroxidation effects of dietary oxidized oil.

Selenium is one these trace mineral elements which is essential for health, immunity and maximum production performance of animals. Selenium is an essential trace element, and its importance for animal health and productivity has been well confirmed. Selenium has known to be involved in enzyme activity and preventing oxidative damage to body tissue. Selenium plays important roles in antioxidant defence systems, prevents cell damage and is necessary for growth, fertility, and immune system in farm animals. Recently, nano -elemental Se has attracted wide spread attention due to its high bioavailability and low toxicity, because nanometer particulates exhibit novel characteristics, such as great specific surface area, high surface activity, a lot of surface active centres, high catalytic efficiency and strong adsorbing ability and over and above the character of low toxicity of Se0. Dietary selenium is an essential trace element for animals and humans with a variety of biological functions. It plays important roles in the regulation of thyroid hormone metabolism, cell growth and antioxidant defence systems thus, together with alpha-tocopherol prevents cells against oxidative stress damage, also these compounds are necessary for growth, fertility, and immune system health in animals and humans. The in situ and in vitro usually use for determining of effect of additives on digestibilities of t feeds. Regarding to the importance of TMR feeding on dairy cattle nutrition, determining of its digestibilities with additive and without additive is necessary. The aim of this study was to investigate the effects of different forms of selenium sources on digestibility of high production lactating dairy cows TMR in vitro and in situ Techniques.

3 male ruminally cannulated sheep, average 43±4.8 kg of BW, were used in a replicated 3×3 Latin square experiment. Sheep were fed twice daily (08:00 and 18:00 h) at maintenance nutrition requirements with a basal diet consisting of 400 g/kg (dry matter) DM of basal concentrates and 600 g/kg DM of forage. Sheep were placed in metabolic cages individually and fresh water was freely available during the experimental period. This experiment was conducted in three periods of 28 days with 21 d adaptation period and 7 d for data tacking. Treatments were: 1. Basal diet + 0.3 ppm nano selenium, 2. Basal diet + 0.3 ppm organic selenium, 3. Basal diet + 0.3 ppm inorganic selenium. In gas production method, 300 mg of each treatment weighted and incubated for 2, 4, 6, 8, 12, 16, 24, 36, 48, 72, 96 hours. The Nylon bag method used to estimate ruminal disappearance of dry matter. Ruminal degradability was measured using nylon bag technique on day 22–28 of the experimental period. The samples 5 g of feed were weighed in 6 cm×12cm nylon bags made of monofilament Pecap polyester . Samples were incubated separately in duplicate bags and suspended in the rumen of each sheep and removed after 0, 2, 4, 8, 12, 16, 24, 36, 48 and 72 hours. All removed bags were rinsed in cold water until the bags were clean; the bags immediately were dried in an oven at 65◦C for 12 h, then 105 ◦C for 24 h in order to determine DM disappearance. in three steps digestion method, about 5 g of feed stuffs weighted in 6 cm×10cm nylon bags made of monofilament Pecap polyester . Samples were incubated separately in duplicate bags and suspended in the rumen of each sheep and removed after 12 hours. All removed bags were rinsed in cold water until the bags were clean; the bags immediately were dried in an oven to determine DM disappearance.

During most of incubation hours, the volume of produced gas was higher in nano selenium, organic selenium, inorganic selenium and control treatments, respectively. However, significant differences between treatments were occurred after 36 h of incubation. The most gas production potential (A) was measured in nano selenium, organic selenium and inorganic selenium compared with control treatments. There were not any significant differences between nano selenium and organic selenium in gas production potential. there wasn’t any significate differences between treatments in degradability of TMR dry matter. In three steps digestion experiment, nano treatment was higher than inorganic treatment in post ruminal digestion of TMR dry matter.

The results showed that the addition of various sources of selenium to the diet may improve rumen function.

Utilization of minerals and vitamins is essential for maximum production and animal health. Vitamin E and selenium perform important functions in the cow. Deficiencies of one, or both, of these nutrients have been implicated in white muscle disease, retained placentas, oxidized milk, lower immune function and mastitis.The roles of these two nutrients are closely related. Both selenium and vitamin E protect cells from the detrimental effects of oxidation but they do so in different ways. Vitamin E, an antioxidant present in the cell membrane, prevents the formation of harmful free radicals. Selenium functions throughout the cell to destroy peroxides, another harmful compound. This explains why selenium will correct some deficiency symptoms of vitamin E and not others. Although feeding large amounts of selenium does reduce the need for vitamin E and vice versa, high levels of one nutrient does not eliminate the need for the other. Selenium and vitamin E have positive and important effects on the growth and maintenance of normal physiological function in animals, especially suckling calves. As recommended by the National Research Association (NRC,2001) the daily requirement of growing calves for Selenium is about 0.30 mg and 40 IU for vitamin E, and the Agricultural Research Association (ARC,1980) for 0.10 mg and 15 IU for selenium and Vitamin E is recommended for growing suckling calves. Selenium as an essential but Low Consumption mineral is important in light of its variation in ruminant vegetable sources (Belali et al 2008) as well as soil selenium deficiency in many parts of the world and Iran (Kajouri & Shirazi 2007, Malekuti et al 2002 and Mehri et al. 2011), on the other hand, since selenium uptake in ruminants is lower than in non-ruminant animals. The importance of providing enough selenium in ruminants' rations doubles and consequently a lack of it can lead to negative changes in the health status and performance of animals. The objective of this study was performed to compare the levels of selenium and vitamin E recommended in NRC and ARC by oral and injectable methods on some blood metabolites, digestibility, performance and Skeletal Growth Indices of suckling Holstein Calves. Twenty five Holstein calves with mean weight of 40±2.7 and 20±5 days and selenium and vitamin E levels of 0.3 mg and 40 IU (as recommended by NRC) and 0.1 mg and 15 IU (as recommended by ARC) respectively, were recruited for this experiment. Were used in a completely randomized design with 5 treatments and 5 replications. Experimental treatments included: 1) control (no selenium and vitamin E), 2) selenium and vitamin E injections as recommended by NRC, 3) selenium and vitamin E injections as recommended by ARC, 4) oral selenium and vitamin E as recommended by NRC, 5 Oral Selenium and Vitamin E were as per ARC recommendation. The duration of the experiment was 35 days. During the experiment, calves were kept in separate locations. The rations were based on NRC (2001). The rations were provided by TMR in calves at 8 am and 16 pm and also had free access to water. Milk feeding was also performed in the morning and evening (10% of body weight). Animals were weighed weekly. To determine the dry matter digestibility of the diets, the calves' feed and faeces were sampled for six consecutive days and kept at -29 ° C until the experiment. Digestibility was determined according to AOAC (1990) methods. Three days a week, the calves' faeces was randomly evaluated. Faeces scores were determined according to the method of Khan et al (2011). On the last day, three hours after morning meal, calves were sampled from the veins and blood parameters, glutathione peroxidase activity and tetrodotyronine and triiodothyronine hormone levels were determined using Pars Test automated analyzer and kit. Measurement of skeletal growth in the body by standard meter and caliper according to the method of Khan et al. (2007). The results of this experiment showed There was no significant difference between treatments in terms of weight performance, dry matter intake, feed conversion ratio and dry matter digestibility (P >0.05). Intake of selenium and vitamin E did not show significant differences between different treatments of glucose, cholesterol, urea nitrogen, total protein, albumin and blood globulin (P>0.05). But blood triglyceride concentration was higher in calves receiving selenium and vitamin E than control (P <0.05). Glutathione peroxidase enzyme activity and blood levels of tetradotyronine and triiodothyronine were also increased in calves receiving selenium and vitamin E compared to control (P <0.05). The results also show that selenium and vitamin E injections orally and according to NRC and ARC recommendation were no significantly different from the control group in terms of faeces score, number of calves with diarrhea and days of calf diarrhea. Did not (P >0.05).There was no significant difference between calves for different skeletal growth indices (P >0.05). Finally, Using selenium and vitamin E in both oral and intravenous methods and both NRC and ARC recommendation did not differ in functional parameters, digestibility and blood metabolites but use of selenium and vitamin E According to the NRC method, the highest increase in blood triglyceride concentration and increased activity of whole blood glutathione peroxidase enzyme and concentration of tetradotyronine hormones and serum triglyceride hormones were higher than other treatments. Overall, the results of this study showed that the use of selenium and vitamin E in both oral and intravenous methods and both NRC and ARC recommendations caused differences in weight gain, dry matter digestibility, stool consistency, skeletal growth and metabolite indices. Blood transfusions are not possible, but the use of selenium and vitamin E injectable and according to the NRC recommends the highest increase in blood triglyceride concentration and increased activity of whole blood glutathione peroxidase enzyme and the concentration of tetradotyronine hormones and other thyridothyronine ratios. It has consequences. Overall, it can be suggested that selenium and vitamin E may be used in suckling calves Nutrition whit Injection, probably because of their higher absorption and according to the NRC method.

In order to study the effect of different levels of zinc and selenium in diets containing oxidized oil on humoral and cellular immunity and relative weight of lymphoid organs in broilers, an experiment performed in a 2×3×2factorial arrangement in a completely randomized design(two Zero and 2% oxidized oil levels, three levels of 0, 40 and 100 mg / kg zinc sulfate, two levels of zero and 0.3 mg / kg selenium) using 480 one-day-old Ross 308 chicks with 12 treatments and 4 replicate per treatment  and 10 chicks per each treatment. To evaluate the immune system, changes in antibody titers were performed by injection of Sheep red blood cell (SRBC) at two times (21 and 28 days) and blood sampling at two times (28 and 35 days). The relative weights of bursa, spleen and thymus were measured at 42 days after slaughter. Cutaneous basophil hypersensitivity (CBH) test was used to evaluate cellular immune system. The results of total antibody titer in first and second times showed significant difference (P <0.05). Maximum grade of primary and secondary total antibodies in chicks fed with 100 mg / kg zinc and 0.3 mg / kg selenium and chicks oil). Containing 100 mg / kg zinc and 0.3 mg / kg selenium and the effect of zinc, Selenium, and their combined supplementation on the initial total antibody grade response was also significant, with 100 mg / kg zinc and 0.3 mg / kg. Selenium significantly increased the initial total antibody titer response. The effect of different experimental groups on IgM antibody response was significant at the first and second time (P <0.05). The cellular immune response of CBH test was not affected by different experimental diets. The effect of treatments on the relative weight of different lymph nodes was not significantly different. The results demonstrated that supplementation of zinc sulfate and sodium selenite improved the immune system of broilers.

This research was carried out to investigate the effects of dietary selenium (Se) sources on hatchability traits in commercial female broiler breeders. The experimental treatment diets were: control (basal diet, none-selenium), basal diet + 0.5 mg sodium selenite (SS), basal diet + 0.5 mg Selenomethionine (S-Meth) and basal diet + 0.5 mg microencapsulated selenium (MS-Met) per kg diet. The total of 100 female and 20 roosters broiler breeder (Arbor Acres® Plus, 38 weeks of age) were considered for present experiment. Semen was collected from roosters by using abdominal massage. Incubation parameters (fertility, hatching, hatch of fertile egg, embryonic mortality, and A-grade chick) were evaluated at 44wk (younger) and 54wk (older) of age. The results indicated that the birds fed an organic sources of selenium (MS-Meth, S-Meth) the percentage of fertility and hatchability was increased (P<0.05) compared to inorganic selenium (SS) and the highest result were obtained in the birds received M-S-Meth diet. Also, the results indicated that embryonic mortality was reduced (P<0.05) in birds fed Se supplemented diet. In conclusion, the use of organic selenium supplementation in diet of could be recommended for improving of hatchability traits in commercial broiler breeders.

The aim of the present experiment was to investigate the effect of diets containing organic and inorganic selenium on growth performance, carcass traits and blood metabolites in geese chickens. A total of 96 one day old native geese were used in a completely randomized design with 3 treatments of 4 replicates with 8 each. The experimental diets were basal diet, basal diet plus 0.3 mg organic Se per kg of diet (Sel-plex) and basal diet plus 0.3 mg inorganic Se per kg of diet (selenite sodium). Growth performance biweekly was calculated by recording during 1-56 days. Phytohemagglutinin test used for the evaluation of cellular immunity at 8 weeks of geese. Bodyweight gain was increased over 2 to 6 weeks and decreased thereafter. Feed conversion rate (FCR) was improved by both selenium sources and the highest FCR value related to the control group in the 8th week. Carcass traits were not affected by various inorganic and organic sources of selenium (P <0.05). Diet supplementation with organic and inorganic Se increased phenolic content and the amount of saturated and unsaturated fatty acids and decreased lipid oxidation after 9 days of storage at 4°C in the refrigerator (P<0.05). Selenium supplementation decreased total blood cholesterol (P <0.05). The cellular immune response was improved in the organic selenium group compared to inorganic selenium and control group (P<0.05). In conclusion, the results of this study suggest that dietary selenium especially organic selenium has desirable potential for improving the performance, immune, and meat quality of goose chickens.

Some previous researches have shown that dietary supplementation with some vitamins and trace elements can increase the ability of animals semen preservation during liquid storage or freezing. Therefore, the aim of this study was to investigate the effect of dietary supplementation of organic selenium and chromium on ram semen quality during liquid storage at 4 °C.

Numbers of 16 Mehraban rams, with ages ranging from 2-4 years and 69.75±10.44 kg average body weight, were divided into four groups of four and were fed by a basal diet consist of 70% forage and 30% concentrate. The experimental design was 2×2×4 factorial experiment based on randomized complete block design. The experiment lasted for 60 days. In this experiment, three factors were including selenium at two levels (0 and 600 µg/day/ram selenium as yeast-selenium), chromium at 2 levels (0 and 1000 µg/day/ram chromium as chromium-methionin) and time at 4 levels (0, 24, 48 and 72 hours after storage). Chromium was fed to rams using edible capsule shells and also selenium by drencher after dissolving in distilled water. In the last three weeks of the experiment, semen samples were collected 3 times. Semen samples after collection was diluted with tirs-egg yolk base extender and stored at 4°C for 72 h. Sperm cells viability, membrane integrity, abnormal morphology, total motility and progressive motility and some motion parameters is detected by computer-assisted sperm analysis at 0, 24, 48 and 72 hours after storage.

The effects of chromium, time and their interaction and also selenium × chromium interaction, selenium × chromium × time interaction were significant for sperm viability and membrane integrity (p < 0.05). The effect of selenium and selenium × chromium interaction was not significant for viability (p>0.05) but, the effect of chromium, selenium and time and also their interaction for membrane integrity was significant (p < 0.05). The viability reduced over time significantly (p < 0.05) and sperm viability in rams receiving the diet contained 1000 μg chromium, was higher than diet without chromium after storage at 4°C for 48 and 72 hours (p < 0.05). In addition, sperm viability in rams receiving the diet contained 600 μg selenium was higher than diet without selenium after storage at 4°C for 48 hours (p < 0.05). Adding 1000 μg chromium to diet containing 600 μg selenium, increased significantly sperm viability after storage at 4°C for 48 and 72 hours (p < 0.05). The membrane integrity reduced over time significantly (p < 0.05) and sperm membrane integrity in rams receiving the diet contained 1000 μg chromium was higher than other groups after storage at 4°C for 24 and 48 hours (p < 0.05). The effect of selenium and chromium and also their interaction was not significant for computer detected parameters (p < 0.05). Interaction of selenium and chromium for abnormal morphology was significant (p < 0.05) but the effects of chromium, selenium, time and their interaction was not significant (p>0.05). Total motility, velocity in curvilinear line, velocity in straight line, velocity in average path decreased over time during semen storage at 4°C (p < 0.05) and diet supplementation of selenium and chromium did not change these parameters (p>0.05). Progressive motility, abnormal morphology and straightness did not affected by time, selenium and chromum.

Generally, dietary supplementation of organic selenium and chromium in rams leads to increased sperm viability and membrane integrity during chilled liquid storage. Dietary supplementation of selenium and chromium did not change computer detected parameters during semen storage at 4°C. In general, the use of organic selenium and chromium in the diet of rams may increase the ability of sperm storage for artificial insemination.

The aim of present study was to produce selenium enriched yeast and determine its optimum level on morphology and biometry of internal and reproductive organs in broiler breeder hens in comparison to Selemax (commercial organic sodium selenite) and mineral selenite. This study was done in two parts, in the 1st experiment; selenium-enriched yeast was produced. In the 2nd experiment, a total of 150 Ross 308 broiler breeder hens (49 weeks of age) were used in 6 treatments of 5 replicates with 5 hens each. The treatments were included: 1) Control group (without selenium), diet containing; 2) 0.15; 3) 0.30 and 4) 0.45 mg/kg of produced selenium enriched yeast (SY0.15, SY0.3, SY0.45, respectively), 5) 0.30 mg/kg Selemax, and 6) 0.30 mg/kg sodium selenite (SS). At the end of the experiment, three hens from each replication were slaughtered. In the 1st experiment, the amount of selenium per kilogram of dry selenium-enriched yeast was 2823 mg. In the 2nd experiment, the number of large follicles in the SY0.45 group was significant higher compared to control, SY0.15 and SS groups. The weight of the abdominal cavity fat of the SY0.45 group was significantly lower compared to control group. Therefore, using of 0.45 mg/kg of produced organic selenium in the broiler breeder diet increased number of large follicles and decreased abdominal cavity fat. Of course, further studies are needed to assessment of other performance and reproductive parameters.

The effects of different sources of selenium supplementation and rosemary essential oil on growth performance, microflora population and intestinal morphology in broiler chicken with using of 480 male broiler chicks in a factorial arrangement (2x5) with 10 treatments and 4 replicates were investigated. Two experimental factors consisted of different sources of selenium (level of 0.3 mg/kg of diet from selenomethionine, nanoselenomethionine, selenitsodium, nano selenium bonza and without selenium) and rosemary essential oil (0 and 300 mg/kg of diet). Results showed that broilers received diet of without Se and rosemary essential oil had lower weight gain and feed intake.Broilers received diet of nano selenium bonza with rosemary essential oil had lower feed conversion ratio as compared to the other broilers (P<0.05). Broilers fed on diets of nanoselenomethionine with rosemary essential oil and nano selenium bonza with rosemary essential oil were increased villus height in jejunum (P<0.05). The crypt depth of intestinal in birds which received nanoselenium was more than the birds that consumed other sources of selenium in the diet (P<0.05). Crypt diameter nano selenium bonza with rosemary essential oil treatment was higher as compared to other treatments (P<0.01). Selenomethionine and nanoselenomethionine alone and in combination with rosemary essential oil treatments had high lactobacillus population and lactobacillus population to total microbial population ratio of ileum as compared to without Se and rosemary essential oil treatment (P<0.05). Based on the results, inclusion nanoselenium (0.3 mg/kg) supplement with rosemary essential oil (300 mg/kg) into the diet of broiler chicken can improve performance, gut morphology and microflora.

Generally, most feeds used in livestock nutrition are deficient in some nutrients, and require nutritional supplements. Among the supplements, micro and macro minerals are particular importance. Selenium (Se) plays an important role in the reproductive function and immune system and is known as an antioxidant and catalyst for the production of thyroid hormone. It is believed that low selenium absorption in ruminants is due to the deficiency of selenium in ration and its conversion into insoluble form. Nano-particles are smaller and more active than larger particles. The importance of Selenium for rumen microorganisms are not entirely clear. Also, selenium is an essential trace element, and its importance for animal health and productivity has been well confirmed. Selenium has known to be involved in enzyme activity and preventing oxidative damage to body tissue.  Selenium plays important roles in antioxidant systems, prevents cell damage and is necessary for growth, fertility, and immune system in farm animals. Recently, nano -elemental Se has attracted wide spread attention due to its high bioavailability and low toxicity, because nanometer particulates exhibit novel characteristics, such as great specific surface area, high surface activity, a lot of surface active centers, high catalytic efficiency and strong adsorbing ability and over and above the character of low toxicity of Se0. Dietary selenium is an essential trace element for animals and humans with a variety of biological functions. It plays important roles in the regulation of thyroid hormone metabolism, cell growth and antioxidant systems thus, together with alpha-tocopherol prevents cells against oxidative stress damage, also these compounds are necessary for growth, fertility, and immune system health in animals and humans. The objective of this research was to investigation the effects of different sources of selenium on digestion characteristics of concentrate mixture of diets in high producing lactating dairy cows using in vitro gas production technique.

Four male ruminally fistulated sheep, average 43±4.8 kg of BW, were used in a replicated 4×4 Latin square experiment. Sheep were fed twice daily (08:00 and 18:00 h) at maintenance nutrition requirements with a basal diet consisting of 400 g/kg (dry matter) DM of basal concentrates and 600 g/kg DM of forage. Sheep were placed in metabolic cages individually and fresh water was freely available during the experimental period. This experiment was conducted in four periods of 28 days with 21 d adaptation period and 7 d for data tacking. Treatments were: 1. Basal diet 2. Basal diet + 0.3 ppm nano selenium, 3. Basal diet + 0.3 ppm seleno methionine, 4. Basal diet + 0.3 ppm selenite sodium. The rumen fluid was mixed with artificial saliva (1:2 ratio, respectively) in lab, and then nano-Selevels and seleno methionine added to it. In gas production method, 300 mg of each treatment weighted and incubated for 2, 4, 6, 8, 12, 16, 24, 36, 48, 72, 96 hours.  In order to determine the effects of different forms of selenium on rumen parameters, concentrations of VFA and NH4, value of pH and population of protozoa were examined. Samples of rumen fluid were collected through the cannula at 4 h after feeding on days 19 and 20 of each collection period for pH, NH3-N, and volatile fatty acids (VFAs) determination. Ruminal pH was immediately measured using an electric pH meter. The samples were subsequently stored frozen at −20 ◦C until analyses.

 Potential of gas production (fraction A) of nano, organic and inorganic treatments were higher (201.9, 344.0, 321.7 and 319.8 ml in control, nano, organic and mineral treatments, respectively) compared to control treatment (P<0.05). The nano selenium treatment had higher VFA concentration (109.83, 98.00 and 89.83 mmol/l in nano, organic and mineral treatments, respectively) when compared with organic and inorganic treatments (P<0.05). Rumen NH4 concentration was not effected by treatments. The organic treatment caused a significant increase in total protozoa population when compared with nano and inorganic treatments (P<0.05).

 The results indicated that selenium supplementation in ruminant diet improves ruminal nutrients degradability's compared to control. Therefore, the use of nano-Se resulted to increase digestibility and fermentation of nutrients resulted improved rumen microorganisms activities. Although nano and organic selenium was better than inorganic treatment in ruminal degradability and rumen parameters, however there was not any significant differences between these two treatments.