Selenium Supplementation of Lactating Dairy Cows: Effect on Selenium Concentration in Blood, Milk, Urine, and Feces

Effects of selenium-enriched yeast dietary supplementation on egg quality, gut morphology and caecal microflora of laying hens

Selenium (Se) is an essential micronutrient for humans and animals and is a powerful antioxidant that can promote reproductive and immune functions. The purpose of this study was to evaluate the effects of supplemental dietary selenium-enriched yeast (SeY) on egg quality, gut morphology and microflora in laying hens. In total, 100 HY-Line Brown laying hens (45-week old) were randomly allocated to two groups with 10 replicates and fed either a basal diet (without Se supplementation) or a basal diet containing 0.2 mg/kg Se in the form of SeY for 8 weeks. The Se supplementation did not have a significant effect on egg quality and intestinal morphology of laying hens. Based on the 16S rRNA sequencing, SeY dietary supplementation effectively modulated the cecal microbiota structure. An alpha diversity analysis demonstrated that birds fed 100 mg/kg SeY had a higher cecal bacterial diversity. SeY dietary addition elevated Erysipelotrichia (class), Lachnospiraceae (family), Erysipelotrichaceae (family) and Ruminococcus_torques_group (genus; p < .05). Analysis of microbial community-level phenotypes revealed that SeY supplementation decreased the microorganism abundance of facultatively anaerobic and potentially pathogenic phenotypes. Overall, SeY supplementation cannot significantly improve intestinal morphology; however, it modulated the composition of cecal microbiota toward a healthier gut.

Combined Supplementation of Two Selenium Forms (Organic and Inorganic) and Iodine in Dairy Cows' Diet to Obtain Enriched Milk, Cheese, and Yogurt

This study evaluated the effects of dietary supplementation in dairy cows with two Se forms (organic and inorganic) and I at the maximum levels permitted in the European Union, with the aim to obtain naturally enriched milk and derived products. A total of 20 Holstein Friesian cows in lactation were fed 2 diets for 64 days: a control diet with a supply of 0.57 mg of inorganic Se and 0.57 mg of I per kg of ration in dry matter (DM), and an experimental diet (SeI) with a supply of 0.34 mg of inorganic Se, 0.23 mg of organic Se, and 5.68 mg of I per kg of ration in DM. The SeI diet did not modify the performance or, in general, the metabolic profile of cows. Se and I levels in milk were affected by diet type and time of measurement (p < 0.01). Thus, a marked increase of both microminerals was evident between the beginning and the end of the test, when the SeI diet was administered. For Se, this increase ranged from 1.95 to 3.29 μg/100 g of milk; and for I, from 19.69 to 110.06 μg/100 g of milk. The SeI diet increased (p < 0.01) the Se and I content in the cheese, reaching levels of 16.4 μg/100 g for Se and 269.7 μg/100 g for I. An increase in I was observed in yogurt from the SeI diet (p < 0.001). The supplementation of two forms of Se and I in the cows' ration, at the levels evaluated, produced milk and dairy products enriched in these microelements without altering their quality parameters. However, a responsible intake of these products is necessary to avoid risks of deficiencies or excesses that could negatively affect the health of consumers.

The effect of supplementary selenium source on apparent and true absorption, retention, performance, and selenium status in lactating Holstein cows

Selenium is an essential trace mineral for dairy cattle and can be provided in the diet in various forms that may differ in bioavailability. The objective of this study was to determine how source of Se affects animal performance, Se status, retention, and apparent and true absorption. Multiparous Holstein cows (n = 24; 597 ± 49 kg body weight) were blocked by days in milk (DIM; 161 ± 18) and randomly assigned to receive 0.3 mg Se/kg of dry matter (100% of NASEM requirements) of either organic Se (ORG; selenized yeast) or inorganic Se (INO; sodium selenite). The Se premix was top-dressed on a common total mixed ration fed daily and mixed into the top 15 cm directly before feeding. Following an 11-wk adaptation period, cows received simultaneous infusions of an intraruminal isotope dose of 77Se in the same chemical form as the premix, and an intravenous dose of 82Se in an inorganic form. Infusions were followed by a 4-d period of blood and rumen fluid sampling, and total collection of feces, urine, and milk. Daily dry matter intake (23 ± 0.6 kg), milk yield (35 ± 1.2 kg), and serum Se (0.11 ± 0.003 µg/g) were not different between treatments during the adaptation period, but milk Se concentrations were greater for ORG compared with INO. Serum 77Se maximum concentration (Cmax) and area under the curve (AUC) were not different between treatments for 72 h following infusion, but rumen fluid 77Se AUC was higher for ORG than INO. Apparent absorption (64 ± 1.4%), and retention (44 ± 1.5%) of the 77Se dose did not differ between treatments. True absorption was calculated using 82Se enrichment in serum and feces and was determined to be 69 ± 1.3% and did not differ between treatments. Fecal excretion of the 77Se dose was not different between treatments (36 ± 1.4%), but ORG had lower urinary excretion and higher milk excretion compared with INO. These results indicate that organic Se resulted in greater Se concentration of milk and lower urinary Se excretion into the environment, but absorption, Se status, and performance of the cow were not affected by Se source at this supplementation level.

Comparison of different organic selenium supplementations on selenium status and serum biomarkers in dairy cows

The objective of this study was to investigate the effects of two different organic selenium (Se) supplements, selenomethionine (Se-Met) and selenohomolanthionine (Se-Hlan), on the serum biochemical parameters and Se status of dairy cows. Different dietary Se supplementation treatments were set as follows: a control group (CON, adding sodium selenite at 0.3 mg Se/kg dry matter [DM]), 0.3 and 0.5 Se-Met (adding Se-Met at 0.3 and 0.5 mg Se/kg DM, respectively), as well as 0.3 and 0.5 Se-Hlan (adding Se-Hlan at 0.3 and 0.5 mg Se/kg DM, respectively). The experiment lasted 8 weeks. The serum measurements showed that both organic Se treatments resulted in higher uric acid than CON. Se-Met produced higher aspartate aminotransferase, glucose, urea, low-density lipoprotein cholesterol, and lactate dehydrogenase than Se-Hlan. Regarding the Se status, the highest milk Se values appeared in 0.5 Se-Met, with intermediate values in 0.3 Se-Met and 0.5 Se-Hlan, whereas the highest and lowest serum Se levels were presented in 0.5 Se-Met and 0.3 Se-Hlan, respectively. Our results suggest that Se-Hlan was not as efficient in boosting serum or milk Se as Se-Met and differences in serum biomarkers between Se-Met and Se-Hlan may be associated with distinct metabolic pathways for different forms of organic Se.

Effect of sustained-release antioxidant bolus on body condition score, blood parameters, uterine health, and some reproductive parameters in transition dairy cows under heat stress condition

The transition period for dairy cows is stressful, and if this occurs during heat stress conditions, it will become more challenging for them. This study aimed to evaluate the effect of sustained-release bolus (Each bolus consisted of a mixture of mineral salts including copper sulfate (8 g), sodium selenite (0.17 g), manganese sulfate (3.9 g), zinc sulfate (2.4 g), and vitamin A (0.47 g) on body condition score (BCS) change, serum metabolites, uterine health, and some reproductive parameters in transition cows with moderate or high pre-calving BCS. Four experimental treatments were (1) moderate BCS without bolus consumption (MB-Bo, n = 35), (2) moderate BCS with bolus consumption (MB + Bo, n = 35), (3) high BCS without bolus consumption (HB-Bo, n = 35), and (4) high BCS with bolus consumption (HB + Bo, n = 35). Results showed that after calving, negative energy balance occurred in all experimental groups. However, cows with high BCS (HB-Bo and HB + Bo) had greater (P = 0.02) BCS change during the postpartum period (0-40 days). Bolus administration decreased white blood cells count 14 days after calving (P = 0.02). Cows with moderate BCS (MB-BO and MB + Bo) had higher (P < 0.01) red blood cell count than cows with high BCS (HB-Bo and HB + Bo) on 14 days after calving. The cows in MB + Bo group had higher (P < 0.05) serum glucose and albumin and lower (P < 0.01) non-esterified fatty acids and beta-hydroxybutyrate. Moreover, this group of cows had higher (P < 0.05) serum total antioxidant capacity, glutathione peroxidase and superoxide dismutase, and lower malondialdehyde (P = 0.03) than other groups. In this regard, the increase in antioxidant capacity with the consumption of blues caused the HB-Bo group to have more incidence of metritis (P = 0.08) and endometritis (P = 0.08). The HB-Bo group had about 12 days longer (P < 0.01) days open than MB + Bo group. It was concluded that consumption of slow-release bolus containing antioxidant elements had positive effect on the metabolic and reproductive status of high-producing dairy cows under heat stress condition.

Effect of sustained release bolus oral administration on body condition change, blood parameters, and uterine health in primiparous cows under heat stress

The transition period is very stressful for primiparous cows due to their first calving experience and will be more challenging if it occurs under heat stress conditions. Heat stress reduces the feed intake of dairy cows. Therefore, it reduces the consumption of minerals and vitamins. Oral administration of boluses through the provision of mineral-vitamin compounds can reduce metabolic abnormalities after calving. The present study aimed to evaluate effect of sustained-release bolus on body condition score (BCS) change, serum metabolites, uterine health, and reproductive status in primiparous cows. Heifers were selected at the beginning of the close-up period (n = 60, BCS = 3.35 ± 0.12). There were 2 experimental treatments at the time of calving: (1) heifers without bolus oral administration (H - Bo, n = 30); (2) heifers with bolus oral administration (H + Bo, n = 30). The results showed that although the rate of BCS loss was lower in the group receiving bolus, the effect of bolus was not significant. The effect of bolus on blood level of glucose, non-esterified fatty acids (NEFA), and beta-hydroxybutyrate (BHBA) was not significant; however, the highest concentration of albumin (P = 0.05) was observed in the H + Bo group on day 42 after calving. The concentration of aspartate transaminase (AST) tended to increase (P = 0.06) on day 14 after calving and entire the study. Total antioxidant capacity (TAC) was affected (P < 0.05) by bolus throughout the period of study, and the highest (P < 0.05) concentration of glutathione peroxidase (GPX) and superoxide dismutase (SOD) was observed in H + Bo group on day 42 after calving. The H + Bo group had the lowest (P < 0.05) vaginal discharge score (VDS). In general, oral administration of the sustained-release bolus in heifers significantly affected the antioxidant factors and uterine health, as well as had positive effects on liver function, body condition, and reproduction status.

Efficacy of feeding hydroxy-selenomethionine on plasma and milk selenium in mid-lactation dairy cows

In this study, we aimed to determine the amount of Se transferred to milk and blood of mid- to late-lactation dairy cows when supplemental Se from hydroxy-selenomethionine (OH-SeMet) was fed compared with an unsupplemented group and a group supplemented with a seleno-yeast (SY). Twenty-four lactating Holstein cows (178 ± 43 d in milk) were used in a complete randomized block design for 91 d (7-d covariate period and 84-d treatment period). Treatments were (1) basal diet with an analyzed Se background of 0.2 mg of Se per kg as-fed (control); (2) basal diet + 0.3 mg of Se/kg as-fed from SY (SY-0.3); (3) basal diet + 0.1 mg of Se/kg as-fed from OH-SeMet (OH-SeMet-0.1); and (4) basal diet + 0.3 mg of Se/kg as-fed from OH-SeMet (OH-SeMet-0.3). During the trial, plasma and milk were analyzed for total Se, and plasma was analyzed for glutathione peroxidase activity. The mean plasma and milk Se concentrations exhibited the same relationship, where OH-SeMet-0.3 resulted in the highest values (142 µg/L of plasma and 104 µg/kg of milk), followed by SY-0.3 (134 µg/L and 85 µg/kg), OH-SeMet-0.1 (122 µg/L and 67 µg/kg), and the control group had the lowest values (120 µg/L and 50 µg/kg). The increment of Se in milk induced by OH-SeMet-0.3 (+54 µg/kg) was 54% higher than that induced by SY-0.3 (+35 µg/kg). Additionally, dietary supplementation of 0.2 mg/kg Se from OH-SeMet in the total mixed ration was estimated to be similar to 0.3 mg/kg Se from SY in the total mixed ration when considering the level of Se in the milk. There was no difference in plasma glutathione peroxidase activity between groups; however, OH-SeMet-0.3 significantly decreased somatic cell count. The results confirmed that supplementation with organic Se increases milk and plasma Se concentrations. Moreover, when administered at the same level of supplementation, OH-SeMet was shown to be more efficient than SY in improving milk quality by increasing Se content and decreasing milk somatic cell count.

Preventive Supplementation of Vitamin E and Selenium as a Factor in Improving the Success Rate of Embryo Transfer in Cattle

The effects of stress on processes in the body are becoming an increasingly relevant research subject. The reproductive ability of bovine animals largely depends on these effects, whilst embryo transfer is increasingly being used as a reproduction method. In this study, we established the differences in the implantation ability of heifers that were treated (N=17) with selenium (Se) and vitamins AD3E, and non-treated heifers. Upon transfer, we took blood samples from both groups and used the total antioxidant status (TAS) value to analyze the presence of reactive oxygen species (ROS), the levels of non-esterified fatty acids (NEFA) and the levels of vitamin E and Se in blood plasma. In the study, we were able to demonstrate that preventive measures in the form of supplementation of vitamin E and Se, mitigate the effects of oxidative stress, strengthen the ability of an organism to improve the dynamic relationship between free radicals and antioxidants, improve the energy status of cattle, positively impact reproductive parameters and increase the success rate of embryo transfer. The difference in the number of successful embryo implantations between the control and treated group was statistically significant, with 64.7% of treated heifers being pregnant after embryo transfer and giving birth to healthy calves. In the control group, the implantation success rate was 41.2%. The supplementation of antioxidants in the form of a combination of vitamin AD3E and Se, proved to be a good method for strengthening the defense of an organism and an effective mean of preventive clinical approach for improving fertility parameters.

Correlations between Sodium Selenite and Vitamin E with Serum Macro-Minerals in Male Lambs

The effects of selenium and vitamin E (Vit. E) were evaluated on the macro-elements and their relationships were also surveyed. Lambs were divided into 4 groups of control, Vit. E, sodium selenite and sodium selenite/Vit. E (Se/E). Sodium selenite (0.1 mg.kg−1) and Vit. E (8 mg.kg−1) were administered. The mean blood selenium was high in sodium selenite. Selenium only in the Se groups was continuously increased. The lowest and highest blood selenium were in Vit. E and sodium selenite, respectively. The mean serum macro-minerals were within the normal range. The trend of calcium and magnesium in the selenium groups was to increase until day 60, but phosphorus was to decline. The lowest and highest calcium were observed in the control and sodium selenite groups, for magnesium in Vit. E and control groups, and for inorganic phosphorus were in the control group, respectively. The comparison of minerals showed that selenium had a significant increase from day 14 to 90 in sodium selenite. Selenium showed the most positive relationships with calcium and inorganic phosphorus in Vit. E and sodium selenite. Overall, selenium was correlated with macro-minerals on day 90 and overall sampling times were with calcium. In conclusion, administration of selenium with Vit. E increased selenium, which was more observed in the sodium selenite group. Sodium selenite alone or with Vit. E had no effect on the macro-minerals. The least correlation was observed between selenium and macro-minerals in the Se/E administration. The correlation between macro-minerals was positive. It was concluded that the effect of sodium selenite on treatment and prevention of selenium deficiency was more effective than other groups. Vit. E per selenium did not change the selenium concentration. Selenium administration was associated with an increase in calcium level and their co-administration is recommended.

Effects of Hydroxyselenomethionine with Symmetrical and Chelated Chemical Structure on Lactation Performances, Anti-Oxidative Status and Immunities, Selenium Transfer Efficiencies for Early-Lactating Dairy Cows

The current study was conducted to investigate effects of hydroxyselenomethionine (HMBSe) with symmetrical and chelated chemical structure, a novel organic selenium (Se) source, on lactation performance, anti-oxidative status and immunities, and transfer efficiencies for early lactation dairy cows compared with that of sodium selenite (SS). Forty-five multiparous early-lactating dairy cows with similar days in milk, 56.0 d and milk yield 36.1 kg/d, were fed with same basal diet containing 0.04 mg of Se/kg of dry matter (DM) basis. They were assigned to 1 of 3 treatments according to one-way ANOVA design: control (basal diet, without Se supplementation), SS (0.30 mg of Se/kg of DM), or HMBSe (0.30 mg of Se/kg of DM). The experiment lasted for 9 weeks, with the first week as adaptation. Results showed that the organic HMBSe cows increased the milk yield, 4% fat-corrected milk yield, the numbers of red blood cells in whole blood, Se concentrations in milk and serum, ratio of milk to serum significantly (P < 0.01); feed efficiency, energy-corrected milk yield, contents of superoxide dismutase in serum, hemoglobin, and the numbers of white blood cells in whole blood significantly (P < 0.05) compared to control and SS. Moreover, HMBSe cows had trends to increase glutathione peroxidase activities (P = 0.09), total antioxidant capacity (P = 0.06), and had trends to decrease the contents of malonaldehyde (P = 0.07) in serum compared to control and SS. In conclusion, HMBSe was more effective on the lactation performances, anti-oxidative status, and immunities and Se transfer efficiencies for early-lactating dairy cows compared to control and SS, which was very meaningful to develop the enriched Se milk products.

Milk selenium content and speciation in response to supranutritional selenium yeast supplementation in cows

The effects of selenium (Se) yeast supplementation on performance, blood biochemical and antioxidant parameters, and milk Se content and speciation were evaluated. Thirty-six mid-lactation Holstein dairy cows were randomly assigned to 1 of 3 treatments: 1) control (basal diet containing Se at 0.11 mg/kg DM), 2) basal diet + 0.5 mg supplemental Se/kg DM (SY-0.5), and 3) basal diet + 5 mg supplemental Se/kg DM (SY-5). Selenium was supplemented as Se yeast. The trial consisted of a 1-week pretrial period and an 8-week experimental period. Milk somatic cell score decreased with SY-5 supplementation (P < 0.05), but other performance parameters were not affected (P > 0.05). The serum Se concentration increased with the increasing levels of Se yeast supplementation (P < 0.05), however, blood biochemical parameters showed few treatment effects. The antioxidant capacity of dairy cows was improved with Se yeast supplementation reflected in increased serum glutathione peroxidase activity (P < 0.05) and total antioxidant capacity (P = 0.08), and decreased malondialdehyde concentration (P < 0.05). Milk total Se concentration increased with Se dose (P < 0.05). Also, the selenomethionine concentration increased with Se dose from 13.0 ± 0.7 μg/kg in control to 33.1 ± 2.1 μg/kg in SY-0.5 and 530.4 ± 17.5 μg/kg in SY-5 cows (P < 0.05). Similarly, selenocystine concentration increased from 15.6 ± 0.9 μg/kg in control and 18.9 ± 1.1 μg/kg in SY-0.5 to 22.2 ± 1.5 μg/kg in SY-5 cows (P < 0.05). In conclusion, Se yeast is a good organic Se source to produce Se-enriched cow milk with increased Se species including selenomethionine and selenocystine. The results can provide useful information on milk Se species when a high dose Se yeast was supplemented in the cow diet.

Heavy Metal Levels in Milk and Cheese Produced in the Kvemo Kartli Region, Georgia

Milk and dairy products are among the most important food sectors in Georgia, and milk is considered one of the most essential foods in the human diet according to Georgian food culture. Kvemo Kartli is one of the major regions in Georgia for milk production. This region suffers from heavy metal contamination in soil and water because of the mining industry. This study was conducted to determine the concentrations of cadmium, lead, iron, zinc, copper, chromium, manganese, cobalt, nickel, selenium and molybdenum in milk and cheese and to evaluate whether the concentrations of these elements correspond to the permissible levels of toxic elements in milk and cheese for Georgia and the EU. In total, 195 milk samples and 25 cheese samples (16 from Imeruli cheese and nine from Sulguni cheese) were collected from nine different villages in the Kvemo Kartli region in Georgia: Chapala, Vanati, Bolnisi, Mtskneti, Sabereti, Ratevani, Khidiskuri, Kazreti, Kvemo Bolnisi. The determination of heavy metal in all samples was carried out by inductively coupled plasma-mass spectrometry. The research results show that the concentration of these elements in most milk samples is fairly constant for all villages and is less than the permissible levels, except for seven samples from the following villages: Kvemo Bolnisi, Bolnisi, Mitskineti and Ratawani, where the concentration of lead in the milk samples was higher than the permissible limits mentioned in the literature, ranging from 0.027 to 1003 mg L⁻¹. As for copper, its concentration in milk in Sabereti and Vanati villages was above the permissible limits according to the EU limit, ranging from 0.42 to 1.28 mg L⁻¹. For cheese samples, the concentration of cadmium, lead, copper, Co and Ni in the two types of cheese was less than the permissible limit according to the laws of Georgia. Finally, the heavy metal concentrations in Imeruli and Sulguni cheese for manganese (Mn), chromium (Cr), selenium (Se), molybdenum (Mo) zinc (Zn) and iron (Fe) were above the permissible limit. Thus, the study results showed that the consumption of milk does not pose a direct and serious threat to the health of consumers. As for the two types of cheese, future studies and continuous monitoring are necessary to assess the cheese content of trace elements and the risk of its consumption to the consumer.

Revisiting the Effects of Different Dietary Sources of Selenium on the Health and Performance of Dairy Animals: a Review

Selenium (Se) is one of the most important essential trace elements in livestock production. It is a structural component in at least 25 selenoproteins such as the iodothyronine deiodinases and thioredoxin reductases as selenocysteine at critical positions in the active sites of these enzymes. It is also involved in the synthesis of the thyroid hormone and influences overall body metabolism. Selenium being a component of the glutathione peroxidase enzyme also plays a key role in the antioxidant defense system of animals. Dietary requirements of Se in dairy animals depend on physiological status, endogenous Se content, Se source, and route of administration. Most of the dietary Se is absorbed through the duodenum in ruminants and also some portion through the rumen wall. Inorganic Se salts such as Na-selenate and Na-selenite have shown lower bioavailability than organic and nano-Se. Selenium deficiency has been associated with reproductive disorders such as retained placenta, abortion, early embryonic death, and infertility, together with muscular diseases (like white muscle disease and skeletal and cardiac muscle necrosis). The deficiency of Se can also affect the udder health particularly favoring clinical and subclinical mastitis, along with an increase of milk somatic cell counts in dairy animals. However, excessive Se supplementation (5 to 8 mg/kg DM) can lead to acute toxicity including chronic and acute selenosis. Se is the most vital trace element for the optimum performance of dairy animals. This review focuses to provide insights into the comparative efficacy of different forms of dietary Se (inorganic, organic, and nano-Se) on the health and production of dairy animals and milk Se content.

Effect of a single, oral administration of selenitetriglycerides, at two dose rates, on blood selenium status and haematological and biochemical parameters in Holstein-Friesian calves

BACKGROUND

Selenitetriglycerides are biologically active, organic forms of selenium formed as a result of the modification of selenic acid and sunflower oil. Studies in rats have shown that they are well absorbed and of low toxicity. There are no published studies on selenitetriglycerides supplementation in calves.

RESULTS

In this study, selenitetriglycerides were administered once orally on the 2nd day of life at a dose of 0.5 or 1 mg Se/kg body weight to each of six Holstein-Friesian calves while six control calves were not supplemented. Blood for determination of selenium concentration, glutathione peroxidase activity, haematological parameters, aspartate aminotransferase, creatine kinase, and lactate dehydrogenase activities and glucose, total protein, albumin, triglycerides, cholesterol, urea, and creatinine concentration was collected before supplementation (day 0) and 1, 2, 5, 10 and 14 days after supplementation. Selenitetriglycerides administration increased (P < 0.01) serum selenium concentration in supplemented calves as early as day1, from a mean of 63.4 to 184.22 µg/l in calves receiving selenium at a dose of 0.5 mg/kg BW, and from 63.17 to 200.33 µg/l in calves receiving 1 mg/kg. Serum selenium concentrations remained significantly higher compared to the control group throughout the experiment. Glutathione peroxidase activity was higher in supplemented than control calves, significantly so in animals receiving the 1 mg/kg dose of Se on the 10th and 14th days (P < 0.05). There were no significant differences in the haematological and biochemical parameters between the groups.

CONCLUSIONS

This experiment showed that supplementation with selenitetriglycerides could significantly improve blood selenium status in calves without adverse effects on haematological or biochemical parameters. These findings are essential prerequisites for future studies on selenitetriglycerides supplementation to manage clinical selenium deficiency in calves.

The Efficacy of a Long-Acting Injectable Selenium Preparation Administered to Pregnant Ewes and Lambs

Simple Summary

Lack of selenium (Se) is a global problem that leads to increased exposure of animals to various diseases, as well as a reduction in productive and reproductive performance. Mineral supplementation can improve the immune system and could therefore be of assistance for lambs. We studied the effects of injectable supplementation with selenium. Supplementation of the Se lead to improved immune status, blood parameters, body weights, and average daily gain of lambs.

Abstract

The aim of this study was to evaluate the effects of a long-acting selenium (Se) preparation administered to sheep. The experiment was conducted on 30 dams and 36 lambs divided into three equal groups of 10 dams and 12 lambs each: Control—C, and two experimental groups—E (Se administered to pregnant ewes) and EI (Se administered directly to lambs after the colostral period). The Se preparation (Barium Selenate Injection, BVP Animal Care, 50 mg/mL) was administered by injection at 1 mL/50 kg (1 mg Se/kg) body weight (BW) to group E ewes in the third month of pregnancy (between 70 and 90 days) and to group EI lambs between 4 and 7 days of age. The following parameters were determined: Se concentration in the blood of ewes, milk yield, milk composition, Se concentration in milk; hematological, biochemical, and immunological parameters and Se concentration in the blood of lambs; growth rate and in vivo measurements of lean meat and fat content in lambs. Barium selenate significantly improved the Se status of dams and lambs, regardless of whether it was administered to pregnant ewes or directly to lambs in the first week of their life. The milk of ewes receiving the Se preparation was characterized by higher concentrations of fat and dry matter. The Se preparation induced significant changes in immunological parameters, thus enhancing defense mechanisms in lambs. The Se preparation exerted more stimulatory effects on humoral and cellular immune responses when administered directly to lambs after the colostral period (group EI) than to pregnant ewes (group E). The results of this study indicate that the long-acting Se preparation delivers benefits to sheep by boosting their immunity and, therefore, improving performance.

Selenium supplementation improves nutrient intake and digestibility, and mitigates CH4 emissions from sheep grazed on the mixed pasture of alfalfa and tall fescue

Low selenium (Se) in soil and forage can adversely affect on the quality of animal-derived foods, and hence on human health. Lambs grazed on mixed pastures of alfalfa (Medicago sativa) and tall fescue (Festuca arundinacea) were supplemented with five levels of Se [0, 3, 6, 9 and 12 µg/kg body weight (BW)]. The intake of dry matter (DM) and organic matter (OM) varied with the level of Se supplementation, with a peak at 6 µg Se per kg BW (p ≤ 0.05). Gross energy (GE) intake, digestive energy (DE) intake and metabolic energy (ME) intake were higher at 6 µg Se per kg BW than at other Se levels (p < 0.01); in addition, methane energy (CH₄ -E) output was lower at 6 µg Se per kg BW. Supplementation with Se significantly increased nitrogen (N) intake, faecal N and urine N, for which the peak values were 20.2 g N/, 5.62 g N/day and 7.92 g N/day, respectively, at 6 µg Se per kg BW. Se intake, blood Se, faecal Se, urine Se and retained Se were negatively correlated with forage crude protein (CP) content (p < 0.001) but were positively correlated with the content of neutral detergent fibre (NDF) (p < 0.001) and acid detergent fibre (ADF) (p < 0.001). Thus, we recommend the addition of 6 µg Se per kg BW to sheep grazed on pastures in regions with low soil Se.

Nano-selenium Supplementation Increases Selenoprotein (Sel) Gene Expression Profiles and Milk Selenium Concentration in Lactating Dairy Cows

Supplementation with selenium is common for dairy cows, but the importance of selenium source is not clear. This study aimed to compare nano-selenium (Nano-Se) and sodium selenite supplements for dairy cows on lactation performance, milk Se levels and selenoprotein (Sel) gene expression. Twelve multiparous Holstein cows were randomly divided into two groups: a control group fed a basal diet plus 0.30 mg Se/kg of DM as sodium selenite or Nano-Se for 30 days. Dry matter intake, milk yield and composition were not affected by dietary Se source (P > 0.05); however, the milk total Se levels and milk glutathione peroxidase (GSH-Px) activities were higher with Nano-Se supplementation than sodium selenite (P < 0.05). At the end of the experiment, Nano-Se supplementation significantly increased plasma Se levels and GSH-Px activity, compared with the sodium selenite supplement. The mRNA expression levels of glutathione peroxidase 1, 2 and 4; thioredoxin reductase 2 and 3; and selenoproteins W, T, K and F were markedly upregulated (P < 0.05) in the mammary gland of the Nano-Se group. Thus, the source of selenium plays an important role in the antioxidant status and in particular the Sel gene expression in the mammary glands of dairy cows, both being stimulated by nano sources.

Can Moderate Levels of Organic Selenium in Dairy Cow Feed Naturally Enrich Dairy Products?

Simple Summary

Milk and dairy products, such as cheese and yogurt, can be useful sources of selenium-enriched products to increase human Se intake. We studied the effect of dairy cow feed supplementation with inorganic plus organic Se on milk yield, and on the Se enrichment of milk and dairy products to obtain naturally enriched products. Two groups of lactating cows were assigned to two feeding treatments, both with 0.240 mg Se/kg of ration dry matter: One was supplemented with inorganic Se, the other with a 60/40 ratio of inorganic Se/organic Se. The results showed that the inclusion of inorganic plus organic Se did not affect the yield or basic chemical composition of milk; however, the Se content of milk was higher with inorganic plus organic Se supplementation. Cheese from cows fed inorganic plus organic Se had a higher Se content, although this effect was not observed for yogurt. At a moderate level in the diet, sodium selenite plus Se yeast may be more effective than only inorganic Se, increasing the Se concentration in milk and cheese.

Abstract

This work studied the effect of dairy cow ration supplementation with inorganic plus organic Se on metabolic status, milk yield, and the quality of milk and dairy products, especially its Se content. Twenty multiparous Holstein Friesian lactating cows were assigned to two feeding treatments. The cows were fed with 22.5 kg dry matter (DM) of total mixed ration (11.75 kg DM of forage plus 10.75 kg DM of concentrate) by head. There were two different concentrates with the same Se content (0.240 mg/kg of ration DM) but with different Se sources: The control (CON) was supplemented with inorganic Se (sodium selenite); and the other (IOSe) was supplemented with sodium selenite plus organic Se (Sel-Plex^®), at 0.144 and 0.096 mg Se/kg of ration DM, respectively. The results indicated that, in general, the IOSe treatment did not modify the metabolic profile, and even decreased the total oxidant status (p < 0.05) and did not lead to a deterioration of quality and yield of milk. However, milk and cheese from IOSe had higher Se content (an increase of 29.7% and 38.2%, respectively) than CON (p < 0.01), but this effect was not observed in yogurt. In general, physical or sensorial parameters of cheeses did not show differences between treatments. Moderate inorganic plus organic Se supplementation may be more effective than inorganic Se, increasing the Se content in milk and cheese, without causing a deterioration in quality or productive parameters.

Effects of Selenium-Enriched Yeast on Performance, Egg Quality, Antioxidant Balance, and Egg Selenium Content in Laying Ducks

This study investigated the effects of dietary selenium-enriched yeast (Se yeast) supplementation on the laying performance, egg quality, plasma antioxidant balance, and egg selenium (Se) content in laying Longyan ducks. A total of 480 32-week-old ducks were randomly divided into four dietary treatments, each consisting of six replicates of 20 ducks. The dietary treatments were a control basal diet and basal diets with supplementation of 0.05, 0.15, and 0.25 mg Se/kg via Se yeast. The analyzed Se contents of the four diets were 0.15, 0.21, 0.36, and 0.43 mg Se/kg, respectively. Dietary Se yeast supplementation had no apparent effects on laying performance and egg quality (p > 0.05), but it improved the antioxidant balance of ducks, as inferred by greater glutathione peroxidase and catalase activities, and decreased the malondialdehyde content in plasma of ducks (p < 0.05). It was suggested that the Se content in the basal diet containing 0.15 mg/kg of Se requirement is adequate for productive performance, but not for the antioxidant balance of laying ducks. Besides that, the Se contents in the yolk, albumen, and whole egg increased linearly as the Se supplementation levels increased. With more feeding days, the Se contents in the yolk and whole egg from non-Se-yeast-supplemented ducks increased linearly (p < 0.05), while those from Se-yeast-supplemented ducks showed a quadratic relationship (p < 0.05). In conclusion, the Se content of the basal diet at 0.15 mg/kg was adequate for laying performance and egg quality traits in laying ducks. Dietary Se yeast supplementation is beneficial to improve the antioxidant balance of laying ducks and increase the Se deposition in eggs for producing Se-enriched eggs. Based on the quadratic model or the quadratic broken-line model analyses, supplemental 0.19 mg Se/kg via Se yeast, with a total equivalent of 0.34 mg Se/kg in the diet, could provide the optimum antioxidant balance in laying ducks. Dietary supplementation of 0.25 mg Se/kg via Se yeast, with a total equivalent of 0.40 mg Se/kg in the diet, could lead to achieving the desired Se content in the whole egg.

Preliminary study on Se-enriched Lentinula edodes mycelium as a proposal of new feed additive in selenium deficiency

The presence of selenium in European soil is low and this causes its deficiency in livestock and, in consequence, in humans. This study aimed to obtain Lentinula (L.) edodes mycelium with the maximum content of selenium. This species was used for experiment based on its documented medicinal properties. Calves were fed with selenium-enriched L. edodes mycelium, and serum selenium concentration, average daily weight gains and selected immune parameters were estimated. The selenium-enriched mushroom was found to be safe based on cytotoxicity tests (MTT and LDH tests) and for this reason it was used for further experiments. The mean quantity of selenium in the serum of calves fed with selenium-enriched L. edodes mycelium was significantly higher than that of control calves. Additionally, the calves fed with selenium-enriched L. edodes mycelium had higher body weight gains than those of control calves. White blood cell counts and subpopulations of lymphocytes in the experimental and control calves were within the reference range. The administration of L. edodes enriched with selenium had a beneficial effect on state of health of the calves.

Selenium biofortified alfalfa hay fed in low quantities improves selenium status and glutathione peroxidase activity in transition dairy cows and their calves

The hypothesis of the study was that feeding a relatively low amount of Se biofortified alfalfa hay during the dry period and early lactation would improve selenium status and glutathione peroxidase activity in dairy cows and their calves. Ten Jersey and 8 Holstein primiparous dairy cows were supplemented with Se biofortified (TRT; n = 9) or non-biofortified (CTR; n = 9) alfalfa hay at a rate of 1 kg/100 kg of BW mixed with the TMR from 40 d prior parturition to 2 weeks post-partum. Se concentration in whole blood, liver, milk, and colostrum, the transfer of Se to calves, and the glutathione peroxidase (GPx) activity were assessed. TRT had 2-fold larger (P < 0.05) Se in blood v. CTR that resulted in larger Se in liver and colostrum but not milk and larger GPx activity in plasma and erythrocytes but not in milk. Compared to CTR, calves from TRT had larger Se in blood but only a numerical (P = 0.09) larger GPx activity in plasma. A positive correlation was detected between Se in the blood and GPx activity in erythrocytes and plasma in cows. Our results demonstrated that feeding pregnant primiparous dairy cows with a relatively low amount of Se-biofortified alfalfa hay is an effective way to increase Se in the blood and liver, leading to greater antioxidant activity via GPx. The same treatment was effective in improving Se concentration in calves but had a modest effect on their GPx activity. Feeding Se biofortified hay increased Se concentration in colostrum but not in milk.

Selenium requirements in grazing dairy cows: a review

In New Zealand, the recommended intake of Se for dairy cattle (0.03 mg/kg dry matter (DM)) is lower than in the United Kingdom and Australia (0.1 and 0.04 mg/kg DM, respectively), and much lower than in the United States of America (0.3 mg/kg DM). Advisors in New Zealand often suggest that New Zealand intake recommendations are far too low and that recommendations from the United States of America should be used. This has created confusion as farmers are given very different advice depending on which recommendations their advisor uses. In this review, we assess whether the published evidence supports the existing dietary requirements and associated Se status thresholds, or if change is required. We focus particularly on the evidence-base in cattle fed a primarily pasture-based diet, as it is critical that dietary recommendations are derived from data created using cows fed similar diets. Accordingly, we also consider whether the increased use of fodder crops, especially during the dry period, is likely to have altered the Se requirements of dairy cows in New Zealand. We report that the science behind the dietary requirements for Se is robust, being supported by factorial models validated using New Zealand data, and on-farm experimental studies. Published nutritional data suggest that the increased use of fodder crops is unlikely to have altered the dietary balance of pro- and antioxidant factors in New Zealand dairy cows in a way that would meaningfully affect Se requirements. However, the lack of specific data on the vitamin E and fatty acid content of the crops being fed in New Zealand means that more information is needed to confirm this conclusion. In general, the existing New Zealand recommendations for Se-status thresholds are supported, although studies are still lacking to properly characterise the upper threshold of the marginal range. Nevertheless many studies in New Zealand, of herds with marginal or low adequate Se status (using New Zealand recommendations), have failed to show an effect of Se supplementation on milk production, intramammary infection or reproductive performance, so it is highly unlikely that the upper threshold of the range is much higher than the current recommendation. Proponents of the hypothesis that Se intakes in New Zealand dairy cattle should be increased by at least 10 times the current recommendations are therefore not using the evidence base correctly.

Injectable organic and inorganic selenium in dairy cows - Effects on milk, blood and somatic cell count levels

Mastitis is the most costly disease of dairy cows. A pro-active approach includes insuring adequate levels of selective trace minerals. The aim of this study was to determine the effect of two different commercially available, injectable selenium products, (sodium) Na-selenite (inorganic) and (selenium) Se-methionine (organic), on milk composition and on serum and milk selenium concentrations in high-yielding Holstein cows on total mix ration. Sixty multiparous cows were randomly selected into three groups of 20, one control group and two groups supplemented with injectable trace minerals. Blood and milk samples were collected over a period of 60 days. No specific change was indicated in milk yield, lactose, milk urea nitrogen (MUN) and milk pH levels compared with baseline values. The Se-methionine supplemented group showed a numerical increase in total milk protein percentage. In the group injected with Se-methionine, a negative correlation was present for the initial 72 hours between serum selenium concentration and somatic cell count (SCC) and a highly significant (p < 0.001) increase in milk selenium concentration for the initial 24 hours. Serum selenium concentration of Se-methionine-supplemented cows was however not significantly changed. Injection of Na-selenite led to a 60-day initial increase in serum selenium concentration above baseline levels and a significant milk selenium concentration on day 1 but to a negative correlation between serum selenium concentration and SCC. Differences in serum and milk selenium concentrations followed with the use of organic and inorganic selenium injectables. Injectable Na-selenite, as selenium, can be of important value for cattle farmers if supplemented on strategically physiological periods to improve production, reproduction and immunity.

The effect of feeding inorganic and organic selenium sources on the hematological blood parameters, reproduction and health of dairy cows in the transition period

The purpose of this study was to investigate the effects of four types of diets containing different forms of selenium on the hematological blood parameters, reproduction and health of dairy cattle during the transition period. Twenty-four close-up dry cows with a mean of 259 ± 1days of pregnancy and expected 21 ± 1days prior to parturition were selected. The cows were fed four diets: 1) basal diet without selenium supplementation (C); 2) basal diet plus 0.5ppm selenium in the form of sodium selenite (Se-S) 3) basal diet plus 0.5ppm selenium in the form of selenium yeast (Se-Y); 4) basal diet plus 0.5ppm selenium in the form of selenomethionine (Se-M). Blood samples for measuring hematological blood parameters (including lymphocyte, red blood cells, hemoglobin, and hematocrit, MCV, MCH, MCHC and RDWc) were taken at 21 and 10 days before delivery, delivery date, 10 and 21 days after delivery. There was no significant difference in hematological parameters before and after delivery in experimental and control groups. However, in the prepartum period, MCH tended to increase significantly in selenium methionine treatment (p<0.05). Reproductive parameters (including distance to first estrus, insemination indexes and number of open days) and health parameters (including rectum temperature and vaginal content score) have been improved by selenium organic supplements. The results of this experiment showed that feeding organic selenium supplementation in multiparous dairy cow’s diet may improve their health and reproduction.

Comparative Nutrient Profiling of Retail Goat and Cow Milk

Goat milk is globally consumed but nutritional profiling at retail level is scarce. This study compared the nutrient composition of retail cow and goat milk (basic solids, fatty acids, minerals, and phytoestrogens) throughout the year and quantified the potential implications on the consumers' nutrient intakes. When compared to cow milk, goat milk demonstrated nutritionally desirable traits, such as lower concentrations of C12:0, C14:0, C16:0 and Na: K ratio, and the higher concentrations of cis polyunsaturated fatty acids (PUFA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), isoflavones, B, Cu, Mg, Mn, P and I, although the latter may be less desirable in cases of high milk intakes. However, in contrast with nutritional targets, it had lower concentrations of omega-3 PUFA, vaccenic acid, lignans, Ca, S and Zn. The extent of these differences was strongly influenced by season and may demonstrate a combination of differences on intrinsic species metabolism, and farm breeding/husbandry practices.

Assessing the ability of silage lactic acid bacteria to incorporate and transform inorganic selenium within laboratory scale silos

Selenium (Se) is a non-metallic trace element essential for normal cellular function, which has been linked with reduced risk of cancer, cardiovascular disease, cognitive decline and thyroid disease in humans. Se deficiency in livestock is associated with white muscle disease, retained placenta, ill-thrift and mastitis. Where Se status or bioavailability from the soil for plants is poor, livestock rely on supplemental Se in their diets predominantly as either sodium selenite (inorganic form) or selenised-yeast (organic form). As lactic acid bacteria (LAB) have been shown to incorporate Se as either organic or elemental (Nano-Se) there may be potential to use silage inoculant bacteria to improve the Se status of feed to provide the Se requirements of livestock. We screened twenty-seven LAB in MRS broth in the presence of sodium selenite for growth and uptake of Se as organic (selenocysteine and selenomethionine), inorganic (selenite and selenate) or/and Nano-Se, with the aim to identify potential candidates for a mini-silo study. Sodium selenite addition into the growth medium of LAB reduced growth rates but also resulted in the conversion of the inorganic sodium selenite into predominately Nano-Se and small quantities of organic-Se. Based on a rank analysis of growth and ability to take up (total Se content) and convert inorganic Se (Nano and organic Se content), three LAB were selected for further investigation as silage inoculants: L. brevis DSMZ (A), L. plantarum LF1 (B), and L. plantarum SSL MC15 (C). Each LAB was used as an inoculant within a grass mini-silo trial, either cultured in the presence of sodium selenite before inoculation or sodium selenite added to the inoculum at inoculation versus controls with no Se. The addition of sodium selenite either into the growth media of LAB or applied at inoculation of grass silage did not interfere with the ability of the LAB to act as a silage inoculant with no difference in silage fermentation characteristic between LAB with no Se added. The addition of sodium selenite either to the LAB growth medium or at inoculation resulted in the conversion of sodium selenite into Nano-Se and organic-Se (Nano-Se, ca. 10³ higher than organic), as previously shown in the screening trial. There was no difference between the three LAB for incorporation of Se or in silage quality, indicating the potential to develop silage inoculants to increase the bioavailable form of Se (elemental and organic) to livestock through conversion of inorganic forms during ensiling.

Bioefficacy of hydroxy-selenomethionine as a selenium supplement in pregnant dairy heifers and on the selenium status of their calves

This study aimed to determine the effects of supplementing pregnant heifers with the organic selenium (Se) source 2-hydroxy-4-methylselenobutanoic acid (HMSeBA) during the last 8 wk of pregnancy on dam and calf Se status. A total of 42 in-calf heifers were recruited to the study and randomly allocated to 1 of 3 treatments; a negative control (Con), sodium selenite (NaSe), or HMSeBA. Animals were blocked by body weight, body condition score, and expected calving date before treatment allocation. Following enrollment, all animals underwent a 7-wk wash-out period, after which they received their respective supplements, top-dressed daily onto a basal diet for the last 8 wk of pregnancy. Heifer blood samples were taken at weekly intervals from enrollment until 2 wk before expected calving date and as soon as possible after calving for determination of whole-blood glutathione peroxidase activity (GSH-Px) and plasma Se and malondialdehyde (MDA) concentrations. Selenized AA were determined in plasma samples taken at 3 wk precalving. A colostrum sample was taken as close to parturition as possible for determination of colostrum total Se, selenized AA, and IgG concentration. Calves were blood sampled as close to birth as possible for determination of whole-blood GSH-Px activity and plasma Se and MDA concentrations. Differences in whole-blood GSH-Px activity did not become apparent until calving; GSH-Px activity was lowest in Con heifers but similar between NaSe and HMSeBA heifers. Plasma Se was lowest in unsupplemented heifers and greatest in those supplemented with HMSeBA; this was attributable to greater selenomethionine concentrations in the plasma of HMSeBA heifers. Colostrum Se was lowest in Con heifers and greatest in HMSeBA heifers. The greater Se concentration of HMSeBA heifers was attributable to a greater proportion of total Se comprising selenocysteine; the reason for this is not known. There was no effect of supplementation on colostrum IgG concentration. Plasma Se was lowest in calves born to Con heifers and greatest in those born to HMSeBA heifers. There were no effects of treatment on calf whole-blood GSH-Px activity or plasma MDA concentration. The enhanced Se status associated with HMSeBA supplementation is likely a consequence of selenomethionine supply and may confer benefits to both the dam and her calf postpartum.

Effect of hydroxyselenomethionine on lactation performance, blood profiles, and transfer efficiency in early-lactating dairy cows

The current study investigated the effects of hydroxyselenomethionine (HMBSe), a novel organic selenium (Se) additive, on lactation performance, blood profiles, antioxidative status, and transfer efficiency of Se in early-lactation dairy cows. Sixty multiparous early-lactating dairy cows with similar days in milk (57 d; standard deviation = 9.9) and milk yield (36.5 kg/d; standard deviation = 1.42) were fed a basal diet containing 0.04 mg of Se/kg (dry matter basis). These cows were assigned to 1 of 4 groups following a randomized complete block design as follows: control (basal diet) or HMBSe addition (0.1, 0.3, or 0.5 mg of Se/kg of dry matter). The experiment lasted for 13 wk, with the first week as adaptation. The results showed that milk yields (raw, protein, and lactose) and feed efficiency were improved in a quadratic manner following increased dietary HMBSe addition, whereas energy-corrected milk, 4% fat-corrected milk, and total solid yields tended to be enhanced quadratically. In terms of whole-blood variables, red blood cell and white blood cell levels were increased quadratically, whereas hemoglobin concentration increased linearly with increased HMBSe addition. Plasma nonesterified fatty acid concentrations tended to increase linearly along with HMBSe addition. Plasma superoxide dismutase activity increased quadratically with increased HMBSe addition. The total antioxidant capacity in plasma tended to improve quadratically when cows were fed more HMBSe. Moreover, plasma malondialdehyde concentrations of dairy cows tended to decrease in a quadratic manner when dietary HMBSe increased. The Se concentrations in milk, plasma, and milk/plasma ratio increased linearly following increased HMBSe addition. In conclusion, HMBSe improved lactation performance, health status, and milk Se concentrations in early-lactating dairy cows.

The impact of organic vs. inorganic selenium on dairy goat productivity and expression of selected genes in milk somatic cells

The aim of this study was to determine the effect of diet supplemented with selenized yeast (Se-yeast) on milk yield and milk composition of goats and expression of casein and mammary-gland-immune system genes in milk somatic cells (MSC). Twenty-four dairy goats in their second to fourth lactations were divided into control and experimental groups, balanced according to lactation number and breed (Polish White or Fawn Improved). Morning milk and blood samples were collected four times during lactation (on the 21st, 70th, 120th, 180th day after kidding). The control and experimental groups were fed diets with 0.7 mg inorganic Se/goat/day (sodium selenite) or 0.6 mg organic Se/goat/day (selenized yeast), respectively. Milk, fat and protein yields during lactation as well as average somatic cell count, fat, protein and lactose contents in milk were evaluated. Microelements in milk and blood serum and biochemical parameters in blood serum were determined at the beginning and the end of the experiment. The expression levels of the genes encoding αS1-casein (CSN1S1), αS2-casein (CSN1S2), κ-casein (CSN3), interleukin 8 (IL-8), serum amyloid A3 (SAA3), interleukin 1β (IL-1β), bactenecin 7.5 (BAC7.5), bactenecin 5 (BAC5), β2-defensin (GBD2), hepcidin (HAMP), chemokine 4 (CCL4), tumour necrosis factor α (TNFα), toll-like receptor 2 (TLR2), cathelicidin-7 (MAP34) and cathelicidin-6 (MAP28) were determined in MSC. Milk, fat, and protein yields were higher and somatic cell count (SCC expressed as natural logarithm) was lower in the milk of goats fed organic Se. The Se concentration in milk was twice as high in the organic vs. inorganic treatment groups at the end of the experiment, while there were no differences in studied biochemical parameters between groups. The transcript levels of CSN1S2 and BAC7.5 were higher and IL-8 was lower in MSC of Se-yeast treated groups. Such results may indicate better health status of mammary glands of goats treated with organic Se as well as positive impact of selenized yeast on the goat's milk composition. Differences in the IL-1β and IL-8 transcript levels were also noted between the stages of lactation, with the highest expression at the peak of lactation (day 70), highlighting the metabolic burden at this time. We concluded that the Se-yeast supplementation improved the productivity and health status of goats and could have significant economic impact on farmer's income.

Manufacturing personalized food for people uniqueness. An overview from traditional to emerging technologies

Personalized nutrition means that we are unique in the way to absorb and to metabolize nutrients as a consequence of our genetic profile and the microbiome that we host in the gut. With the terminology of Personalized Food Manufacturing we want not only to stress the idea of the capability to manufacture food meeting our unique nutritional needs but - based on the idea that eating is a global experience - also to broad this to meet additional personal requirements and expectations, i.e. taste, texture, color, aspect, etc. To address this aim, traditional and advances technologies will have to be employed in new ways and new technological solutions will have to be implemented. All these considerations motivated our paper by which we want to explore and to discuss the technological options having the potential to produce personalized food. After pointing out the main diet styles, firstly we have analyzed the modern approaches of agricultural and animal nutrition in use to manufacture food for narrow group of consumers. Secondly, we have explored emerging technologies at disposal employable to manufacture customized food that meet our uniqueness. Finally the most important market products belonging in the sector of personalized food production have been considered.

The potential of silage lactic acid bacteria-derived nano-selenium as a dietary supplement in sheep

Context Selenium (Se) is a trace element essential for cellular function in animals as a component of the enzymes glutathione peroxidase and iodothyronine-5-deiodinase. In many parts of Europe, Se is often deficient in livestock diets due to the low Se status of soil. Supplementation of diets with selenised yeast (predominately as seleno-methionine) or inorganic sodium selenite is common practice in most livestock systems, including ruminants. Lactic acid bacteria have been shown to convert inorganic Se into predominantly elemental nano-Se, which has been used recently in human pro-biotics as a less toxic form of Se. Therefore, silage lactic acid bacteria may provide a supplementation route of bioavailable nano-Se for ruminants. Aim Here, we report on the effect of feeding inoculated silage enriched with a supra-nutritional level of nano-Se (Selage) versus control inoculated silage (Silage) on the Se status of finishing lambs and their products, followed by a second study where blood parameters were investigated in ewes. Methods In the first study, 40 Charollais × Suffolk lambs (42 ± 1.7 kg) were paired according to weight and sex, then allocated to the two treatments for 8 or 10 weeks. Uptake of Se into wool was temporally assessed, as well as excretion of Se into faeces. Selenium concentrations in blood and muscle, carcass characteristics and meat quality are reported postmortem. In the second study, individually penned Suffolk × Mule ewes (n = 12; 76 ± 4.5 kg) were offered the same diets as in the first study. Blood parameters were assessed at the start and after 6 weeks, with intake and excretion into faeces and urine assessed temporally throughout the study. Key results In the first study, dry-matter (DM) intake was similar in both treatment groups, at 0.8 ± 0.03 kg/day, but Se concentrations of the diets were significantly different, resulting in intakes of ~0.14 and 1.60 mg/day on the Silage and Selage diets, respectively. This was reflected in higher Se concentrations in faeces (0.4 vs 2.0 mg/kg DM; P &lt; 0.001), wool (0.11 vs 0.25 mg/kg DM; P &lt; 0.001), blood (0.19 vs 0.46 mg/L; P &lt; 0.001) and muscle (0.31 vs 0.41 mg/kg: P &lt; 0.01) on the Selage than on the Silage diet. Colour (chroma) shelf life of the meat was significantly higher on the Selage treatment (8.05 vs 9.2 days; P &lt; 0.05). In the second trial, for ewes fed Selage, blood seleno-methionine increased from 0.21 to 0.25 mg/L and seleno-cysteine from 0.25 to 0.35 mg/L after 6 weeks on the treatment, whereas there was no change in ewes fed Silage. Glutathione peroxidase increased, whereas haematocrit, haemoglobin and platelet count were decreased across time during the study, but there was no difference between the treatments. Conclusions Nano-Se provided by the Selage treatment was shown to be available to sheep and improve shelf life, with no adverse haematological effects. Implications There is potential to use silage inoculants to provide bioavailable Se to ruminants. Further research is required to determine the most appropriate dose for animal performance and product quality.

Supplemented Organic and Inorganic Selenium Affects Milk Performance and Selenium Concentration in Milk and Tissues in the Guanzhong Dairy Goat

Trace amounts of selenium (Se) are essential for several organisms, and deficiencies therein have adverse effects on growth, development, and reproduction; this is particularly significant in animals raised for milk and livestock production. To study the effect of Se on Guanzhong dairy goats, their diets were supplemented with different sources (inorganic or organic) and Se concentrations (0.2 or 0.4 mg Se/kg). A non-Se-fortified basal diet served as a negative control, and a sixth treatment group received both inorganic and organic Se sources (0.2 mg Se/kg diet each). Dietary Se supplementation increased milk production, with organic Se being more effective than inorganic Se. Selenium supplementation also increased Se concentration and glutathione peroxidase activity in whole blood, with organic Se more effective than inorganic Se at the same Se concentration. With increasing Se in diets, the Se content in milk increased markedly, reaching a plateau value at day 30 in all groups, and organic Se (0.4 mg/kg diet) had the best effect. In addition, dietary Se sources and concentrations markedly affected Se concentrations in different tissues and organs. Thus, organic Se supplementation of a basal diet at 0.4 mg/kg is practically applicable for Se-enriched milk and meat production in Guanzhong dairy goats.

Effect of Selenium from Selenium-Enriched Kale Sprout Versus Other Selenium Sources on Productivity and Selenium Concentrations in Egg and Tissue of Laying Hens

A 6-week trial was conducted to compare the effect of selenium (Se) from hydroponically produced Se-enriched kale sprout (HPSeKS), sodium selenite (SS), and Se-enriched yeast (SeY) in laying hens. A total of 144 40-week-old hens were randomly divided into four groups, according to a completely randomized design. Each group consisted of four replicates with nine hens per replicate. The dietary treatments were T1 (basal diet) and T2, T3, and T4 (basal diets supplemented with 0.30 mg Se/kg from SS, SeY, and HPSeKS, respectively). Results showed that Se supplement did not affect (p > 0.05) productivity and egg quality. Hens fed Se from HPSeKS and SeY exhibited higher (p < 0.05) Se bioavailability than hens fed Se from SS. Whole egg Se concentration of hens fed Se from HPSeKS was similar (p > 0.05) to that of hens fed Se from SeY, but higher (p < 0.05) than that of hens fed Se from SS. However, the breast muscle and heart tissue Se concentrations of hens fed Se from SS, SeY, and HPSeKS were not different (p > 0.05). The results of this trial demonstrated that Se from HPSeKS and SeY was more efficient than Se from SS on Se bioavailability and whole egg Se concentration in laying hens.

Blood biochemical indicators and concentration of thyroid hormones in heavily pregnant and lactating ewes depending on selenium supplementation

The aim of this research was to determine the effect of dietary selenium supplementation (organic and inorganic) on the biochemical indices and thyroid hormone concentration in the blood of heavily pregnant and lactating ewes. Research was conducted on 30 pregnant ewes of the Merinolandschaf breed divided into 3 groups, and lasted for four months (two months on ewes in late pregnancy and two months on ewes during lactation). The first group was given a basal diet without the addition of selenium. The feed mixture of group 2 was supplemented with 0.3 mg/kg of organic sources of selenium, and group 3 with the same amount of inorganic sources of selenium. In lactating ewes, organic and inorganic selenium lead to a significant (P< 0.05;P< 0.01) increase in urea concentration. At the same time, in lactating ewes inorganic selenium had a significant decreasing effect (P< 0.05;P< 0.01) on cholesterol, low-density lipoprotein and triglycerides. Organic selenium in heavily pregnant ewes significantly (P< 0.01) increased aspartate aminotransferase activity in comparison to group 1 and 3. In lactating ewes significant (P< 0.05) differences in aspartate aminotransferase activity were determined between groups 2 and 3. With selenium supplementation a significant (P< 0.01;P< 0.05) increase concentration of Se was determined (for heavily pregnant and lactating ewes, respectively), as well as Na, Cl, Fe (lactating ewes), and a decrease of K (high pregnant ewes). Organic selenium had an effect on the increase of triiodothyronine in lactating ewes. We can conclude that selenium supplementation contributes to good health and condition of ewes in the demanding period of lactation.

Development of mathematical models to predict calcium, magnesium and selenium excretion from lactating Holstein cows

The aim of this study was to develop and evaluate mathematical models that predict mineral excretion, particularly calcium (Ca), magnesium (Mg) and selenium (Se), from lactating dairy cows. Mineral excretion can be affected by several dietary factors. A deficiency in Ca or Mg application to pasture, among other factors, can contribute to grass tetany or wheat pasture poisoning in cows, whereas an excess can cause runoff into water supplies. Manure application with high Se concentration can also result in runoff, causing the bioaccumulation of selenium in aquatic ecosystems, wetland habitats and estuaries, leading to toxic levels in fish. A database composed of studies relating to mineral utilisation in lactating dairy cows conducted after and including the year 2000 was compiled. A meta-analysis was conducted with the aim of creating multiple empirical equations to predict Ca, Mg and Se excretion from lactating dairy cows. Calcium intake, feed Ca content, milk yield, milk protein content and acid detergent fibre content in diet were positively and linearly related to Ca excretion. Dietary crude protein content and milk fat content were negatively related to Ca excretion. Magnesium intake, feed Mg content and milk yield were positively and linearly related to Mg excretion. Selenium content of diet and dry matter intake were linearly and positively related to Se excretion. Two sets of models were developed using or excluding the intake variable and both sets of models were evaluated with independent data originating from commercial herd or individual animals. In general, intake measurements improved prediction when evaluated with independent datasets (root mean square prediction error = 8% to 19% vs 14% to 26% of the average observed value). There were substantial mean biases, particularly those evaluated with data from a commercial farm, perhaps due to inaccurate feed intake measurements. Although there was generally good agreement between predicted and observed mineral excretion, model development and evaluation would benefit from an expanded database.

A Summary of New Findings on the Biological Effects of Selenium in Selected Animal Species-A Critical Review

Selenium is an essential trace element important for many physiological processes, especially for the functions of immune and reproductive systems, metabolism of thyroid hormones, as well as antioxidant defense. Selenium deficiency is usually manifested by an increased incidence of retention of placenta, metritis, mastitis, aborts, lowering fertility and increased susceptibility to infections. In calves, lambs and kids, the selenium deficiency demonstrates by WMD (white muscle disease), in foals and donkey foals, it is associated with incidence of WMD and yellow fat disease, and in pigs it causes VESD (vitamin E/selenium deficiency) syndrome. The prevention of these health disorders can be achieved by an adequate selenium supplementation to the diet. The review summarizes the survey of knowledge on selenium, its biological significance in the organism, the impact of its deficiency in mammalian livestock (comparison of ruminants vs. non-ruminants, herbivore vs. omnivore) and possibilities of its peroral administration. The databases employed were as follows: Web of Science, PubMed, MEDLINE and Google Scholar.

Hydroxy-selenomethionine: A novel organic selenium source that improves antioxidant status and selenium concentrations in milk and plasma of mid-lactation dairy cows

This study aimed to evaluate the effect of hydroxy-selenomethionine (HMSeBA), a novel organic selenium (Se) source, on milk performance, antioxidative status, and Se concentrations in the milk and plasma of mid-lactation dairy cows compared with that of sodium selenite (SS). Fifty mid-lactation dairy cows with similar days in milk, milk yield, and parity received the same basal diet containing 0.06 mg of Se/kg of DM. They were assigned to 1 of 5 treatments according to a randomized complete block design: negative control (without Se supplementation), SS supplementation (0.3 mg of Se/kg of DM; SS-0.3) or HMSeBA supplementation (0.1, 0.3, or 0.5 mg of Se/kg of DM: SO-0.1, SO-0.3, and SO-0.5, respectively). The experiment lasted for 10 wk, including a pretrial period of 2 wk. The results indicated that neither Se supplementation nor Se source affected dry matter intake, milk yield, milk composition, or blood biochemical parameters, except for milk fat percentage. Simultaneously, milk fat percentage and milk fat yield increased linearly as the quantity of HMSeBA supplementation was increased. Production of 4% FCM and ECM was elevated linearly as dietary HMSeBA increased. The SO-0.3 group showed higher serum activity of glutathione peroxidase, total antioxidant capacity, and superoxide dismutase than the SS-0.3 group, but malondialdehyde content was not affected by Se source. Furthermore, HMSeBA supplementation linearly increased the activities of serum glutathione peroxidase and superoxide dismutase, but decreased malondialdehyde content. Compared with the SS-0.3 group, the SO-0.3 group showed augmented concentrations of total Se in milk and plasma, and total Se milk-to-plasma concentration ratio. In addition, increasing doses of HMSeBA linearly increased the concentrations of total Se in the milk and plasma. This study demonstrates that HMSeBA improves antioxidant status and increases milk and plasma Se concentrations more effectively than SS, indicating that HMSeBA could replace SS as an effective organic Se source for lactating dairy cows.

Improving the quantity, quality and transparency of data used to derive radionuclide transfer parameters for animal products. 2. Cow milk

Under the International Atomic Energy Agency (IAEA) MODARIA (Modelling and Data for Radiological Impact Assessments) Programme, there has been an initiative to improve the derivation, provenance and transparency of transfer parameter values for radionuclides from feed to animal products that are for human consumption. A description of the revised MODARIA 2016 cow milk dataset is described in this paper. As previously reported for the MODARIA goat milk dataset, quality control has led to the discounting of some references used in IAEA's Technical Report Series (TRS) report 472 (IAEA, 2010). The number of Concentration Ratio (CR) values has been considerably increased by (i) the inclusion of more literature from agricultural studies which particularly enhanced the stable isotope data of both CR and F_m and (ii) by estimating dry matter intake from assumed liveweight. In TRS 472, the data for cow milk were 714 transfer coefficient (F_m) values and 254 CR values describing 31 elements and 26 elements respectively. In the MODARIA 2016 cow milk dataset, F_m and CR values are now reported for 43 elements based upon 825 data values for F_m and 824 for CR. The MODARIA 2016 cow milk dataset F_m values are within an order of magnitude of those reported in TRS 472. Slightly bigger changes are seen in the CR values, but the increase in size of the dataset creates greater confidence in them. Data gaps that still remain are identified for elements with isotopes relevant to radiation protection.

How knowledge of the gastrointestinal absorption of elements could be used to predict transfer to milk

The quality and quantity of data used to derive transfer parameter values for milk are variable and there are many data gaps for elements/radionuclides which may need to be considered for risk assessment of the agricultural foodchain. There has been a recent focus on critically evaluating current methods to fill data gaps and on identifying extrapolation methods to derive suitable values for the elements, and particularly radioisotopes, with no or sparse data. The relationship between fractional absorption of elements in the ruminant gastrointestinal tract and transfer to milk has been explored to determine whether knowledge of the former can be used to predict the latter. A relationship has been derived between fractional absorption of elements and two empirical ratios commonly used to quantify transfer to milk; transfer coefficients (element concentration in milk divided by element daily intake) and concentrations ratios (concentration in milk divided by concentration in feed). We propose that fractional absorption may be used to predict the order of magnitude of the transfer to milk of elements/radionuclides for which no relevant data have yet been identified or collated.

Selenium-fertilized forage as a way to supplement lactating dairy cows

Fertilization with Se improves forage organic Se concentration, but comparisons with other forms of Se supplementation in feeding lactating dairy cows are scarce. Our objective was to compare the effect of Se-enriched forages to dietary sources of inorganic and organic Se. Digestibility, retention, and balance were assessed by measuring Se concentrations in feces, urine, milk, and blood. The resulting effect on antioxidant status and lactation performance of dairy cows was also determined. High-Se silages [1.72 mg of Se/kg of dry matter (DM)] were produced following a spring application of 2.5 kg/ha of Selcote Ultra, whereas low-Se silages (0.05 mg of Se/kg of DM) were produced in the Se-unfertilized portion of the same fields. After a 77±17 d period of Se depletion, 33 late-lactation primiparous Holstein cows were blocked and randomly assigned for 43 d to 1 of 4 experimental total mixed rations fed for ad libitum intake in an unbalanced randomized block design. Treatments consisted of 4 diets: control with low-Se silages, without Se supplement (0.12±0.04 mg of Se/kg of DM); ISe with low-Se silages and inorganic Se (0.80±0.14 mg of Se/kg of DM); YSe with low-Se silages and organic Se from yeast (0.70±0.11 mg of Se/kg of DM); and FSe with high-Se silages, without Se supplement (0.79±0.14 mg of Se/kg of DM). Organic Se, either as YSe or FSe, was more available and more effective to increase blood and milk Se concentrations than ISe. Moreover, FSe was more available than YSe, as cows fed FSe excreted 16 and 22% less Se (as percentage of intake) in feces and urine, respectively, had higher Se apparent absorption (17%), retention (37%), and balance (45%), and had greater concentration of Se in serum (16%) and milk (11%) than cows fed YSe. Antioxidant status (whole blood and plasma glutathione peroxidase, and milk thioredoxin reductase and malondialdehyde) was not affected by treatments. Dry matter intake, yield of actual, energy-corrected, and fat-corrected milk, as well as milk fat and lactose concentrations, were not affected by the dietary treatments. Cows fed ISe had lower milk protein concentration (3.44%) than cows fed YSe (3.58%) or FSe (3.51%). Cows fed Se-supplemented diets had a lower milk somatic cell count than cows fed the control diet. Results from the current study showed that the production of Se-enriched forages is an effective method to supplement dairy cows in Se as it was more available than YSe, and did not alter antioxidant status and performances of lactating dairy cows.

Effects of dietary supplementation of selenium and iodine on growth performance, carcass characteristics and histology of thyroid gland in goats

This study assessed the effects of dietary selenium (Se), iodine (I) and a combination of both on growth performance, thyroid gland activity, carcass characteristics and the concentration of iodine and selenium in Longissimus lumborum (LL) muscle in goats. Twenty-four bucks were randomly assigned to four dietary treatments: control (CON), basal diet without supplementation, basal diet + 0.6 mg Se/kg dry matter (DM) (SS), 0.6 mg I/kg DM (IP), or combination of 0.6 mg/kg DM Se and 0.6 mg/kg DM I (SSIP) and fed for 100 days. Animals fed diet SSIP exhibited higher (P < 0.05) body weight and better feed conversion ratio (FCR) than those fed other diets. Dressing percentage of goats fed the supplemented diets was higher (P < 0.05) than that of the control. Carcasses from the IP group had higher (P < 0.05) total fat proportion than the SSIP group. The levels of both elements were significantly elevated (P < 0.05) in LL muscle in supplemented goats. Thyroid follicular epithelial cells of IP and SSIP animals were significantly higher than those of CON and SS groups. The study demonstrated that the combined Se and I dietary supplementation improves growth performance, carcass dressing percentage and increases the retention of Se and I in goat meat.