Effects of selenium deficiency on principal indexes of chicken kidney function

Synergistic effects of T-2 toxin and selenium deficiency exacerbate renal fibrosis through modulation of the ERα/PI3K/Akt signaling pathway

As common pathogenic agents in the world and widely distributed globally, T-2 toxin and selenium deficiency might exacerbate toxic effects by combined exposure, posing a dramatic health hazard to humans and animals. In this study, we aim to elucidate the underlying mechanisms of renal fibrosis triggered by T-2 toxin and selenium deficiency exposure. A total of thirty-two rats are randomly divided into the normal control, T-2 toxin, selenium deficiency, and combined intervention groups. T-2 toxin (100 ng/g) is intragastric gavaged to the rats in compliance with the body weight. Both the standard (containing selenium 0.20 mg/Kg) and selenium-deficient (containing selenium 0.02 mg/Kg) diets were manufactured adhering to the AIN-93 formula. After 12 weeks of intervention, renal tissue ultrastructural and pathological changes, inflammatory infiltration, epithelial mesenchymal transition (EMT), and extracellular matrix (ECM) deposition are evaluated, respectively. Metabolomics analysis is conducted to explore the underlying pathology of renal fibrosis, followed by the validation of potential mechanisms at gene and protein levels. T-2 toxin and selenium deficiency exposure results in podocyte foot process elongation or fusion, tubular vacuolization and dilatation, and collagen deposition in the kidneys. Additionally, it also increases inflammatory infiltration, EMT conversion, and ECM deposition. Metabolomics analysis suggests that T-2 toxin and selenium deficiency influence amino acid and cholesterol metabolism, respectively, and the estrogen signaling pathway is probably engaged in renal fibrosis progression. Moreover, T-2 toxin and selenium deficiency are found to regulate the expressions of the ERα/PI3K/Akt signaling pathway. In conclusion, T-2 toxin and selenium deficiency synergistically exacerbate renal fibrosis through regulating the ERα/PI3K/Akt signaling pathway, and inflammatory infiltration, EMT and ECM deposition are involved in this process.

Effects of different levels of organic chromium and selenomethionine cocktails in broilers

Selenium (Se) is an essential trace mineral that plays an important role in physiological processes by regulating the antioxidant defense system and enhancing immunity. Chromium is an essential mineral involved in carbohydrate and lipid metabolism and also plays a role in maintaining normal insulin function. Based on these advantages, we hypothesized that the addition of selenomethionine (SeMet) and organic chromium (OC) to broiler diets would increase Se deposition, antioxidant capacity and immune response in meat. Therefore, this study analyzed the effects of OC and SeMet on growh performance, nutrients digestibility, blood profiles, intestinal morphology, meat quality characteristics, and taxonomic analysis of broilers. A total of 168 one-day-old broiler chicken (Arbor Acres) were randomly allotted to 3 groups based on the initial body weight of 37.33 ± 0.24 g with 7 replicate per 8 birds (mixed sex). The experiments period was 28 days. Dietary treatments were folloewd: Basal diets based on corn-soybean meal (CON), basal diet supplemented with 0.2 ppm OC and 0.2 ppm SeMet (CS4), and basal diet supplemented with 0.4 ppm OC and 0.4 ppm SeMet (CS8). Supplementation of OC and SeMet did not affect on growth performance, nutrient digestibility. However, CS8 supplementation increased in duodenum villus height and villus height : crypt depth, and increased in breast meat Se deposition. In addition, CS8 group showed higher uric acid and total antioxidant status than CON group. Taxonomic analysis at phylum level revealed that Proteobacteria and Firmicutes of CS4 and CS8 were lower than CON group. In genus level, the relative abundance of fecal Lactobacillus and Enterococcus of CS4 and CS8 groups were higher than CON group. In short, 0.4 ppm OC and 0.4 ppm SeMet supplementation to broiler diet supporitng positive gut microbiome change, also enhancing antioxidant capacity, and Se deposition in breast meat.

Lead exposure induced developmental nephrotoxicity in Japanese quail (Coturnix japonica) via oxidative stress-based PI3K/AKT pathway inhibition and NF-κB pathway activation

Birds are sensitive to environmental pollution and lead (Pb) contamination could negatively affect nearly all avian organs and systems including kidney of excretive system. Thereby, we used a biological model species-Japanese quail (Coturnix japonica) to examine the nephrotoxic effects of Pb exposure and possible toxic mechanism of Pb on birds. Quail chicks of 7-day-old were exposed to 50 ppm Pb of low dose and high dose of 500 ppm and 1000 ppm Pb in drinking water for five weeks. The results showed that Pb exposure induced kidney weight increase while body weight and length reduction. The increase of uric acid (UA), creatinine (CREA) and cystatin c (Cys C) in the plasma suggested renal dysfunction. Moreover, both microstructural and ultrastructural changes demonstrated obvious kidney damages. In particular, renal tubule epithelial cells and glomeruli swelling indicated renal inflammation. Furthermore, changes in the content and activity of oxidative stress markers suggested that Pb caused excessive oxidative stress in the kidney. Pb exposure also induced abnormal apoptosis in the kidney. In addition, RNA sequencing (RNA-Seq) analysis revealed that Pb disturbed molecular pathways and signaling related with renal function. Especially, Pb exposure resulted in an increase in renal uric acid synthesis by disrupting purine metabolism. Pb caused apoptotic increment by inhibiting the phosphatidylinositol-3-kinase (PI3K)/RAC-alpha serine/threonine-protein kinase (AKT) pathway and induced aggravated inflammation by activating Nuclear Factor kappa B (NF-κB) signaling pathway. The study implied that Pb caused nephrotoxicity through structural damages, uric acid metabolism disorder, oxidation imbalance, apoptosis and inflammatory pathway activation.

MiR-1656 targets GPX4 to trigger pyroptosis in broilers kidney tissues by activating NLRP3 inflammasome under Se deficiency

Selenium (Se) is a vital minor element for the organism. Se deficiency caused inflammation in kidney tissue and regulate the expression of selenoproteins and microRNAs (miRNAs). Pyroptosis involved in the inflammatory response, however, whether microRNA targets GPX4 to regulate Se-deficient kidney tissue pyroptosis is unclear. In this study, broilers were divided into two groups, Control group with 0.3mg/kg Se diet and Se-deficient group with 0.03mg/kg Se diet. The dual luciferase reporter assay system and quantitative real-time PCR (qRT-PCR) were used to screen the specificity of miR-1656 and its target protein in Se-deficient broilers. We tested the pyroptosis-related genes of Se-deficient broilers kidney and miR-1656-transfected primary broilers kidney by qRT-PCR, Western blot (WB) and immunofluorescence staining. Our research indicated that the GPX4 is one of the target genes of miR-1656, and Se deficiency leaded to the overexpression of miR-1656 and the increased expression of pyroptosis-related genes. The overexpression of miR-1656 can induce increased expression of pyroptosis-related genes including NLRP3, Caspase-1, IL-18, and IL-1β by inhibiting the release of GPX4. This study showed that miR-1656 could increase the release of ROS by targeting GPX4, activated the NLRP3 inflammasome, and release the inflammatory factors IL-1β and IL-18 to trigger pyroptosis in the kidney tissue of Se-deficient broilers. This finding may provide new research ideas for kidney injury and cell death due to Se deficiency.

Effects of supplementing diet with Thyme (Thymuas vulgaris L.) essential oil and/or selenium yeast on production performance and blood variables of broiler chickens

Background

Organic products for animals are becoming more widely accepted by consumers. Using herbal additives may lead to more healthy animal products. In this research, it is hypothesized that thyme essential oil (TEO) and/or selenium yeast (SY) would be helpful to enhance production performance in broilers.

Objective

In the current study, the effects of adding TEO and/or SY to the diet on broiler performance and blood parameters were evaluated in broiler chickens.

Methods

A total of 480 chicks were distributed in 24 cages with 20 chicks (10 males and 10 females) each and assigned to be fed four iso‐caloric and iso‐nitrogenous diets including two levels (0 and 250 mg/kg) of TEO and two levels (0 and 0.3 mg/kg) of SY in a 2 × 2 factorial arrangement with six replicates.

Results

Adding SY significantly decreased feed intake in finishing period (22–42 d) (p < 0.05). Supplementation with SY and TEO significantly decreased plasma uric acid and triglyceride levels, respectively (p < 0.05). However, neither of the supplements had any influence on the plasma glucose and albumin levels (p > 0.05). The lowest level of plasma cholesterol was detected in the birds fed the TEO‐supplemented diet (p < 0.05). Addition of SY significantly increased blood glutathione peroxidase activity (p < 0.05).

Conclusions

Dietary supplemental TEO has a favourable effect on feed intake, weight gain, and body weight values. Besides, SY may decrease blood concentration of uric acid, as well as blood glutathione peroxidase activity. An interaction is detected between TEO and SY on blood cholesterol.

Effects of maternal and progeny dietary selenium supplementation on growth performance and antioxidant capacity in ducklings

This study evaluated the effects of selenium (Se) supplementation in maternal and offspring diets on performance and antioxidant capacity of ducklings aged from 0 to 2 wk. A total of 144 female Longyan duck breeders aged 22-wk were allotted into 2 treatments and fed a control diet or a 0.16 mg Se/kg supplemented diet. At 40-wk, 120 offspring from each treatment were divided into 2 groups, with 6 replicates of 10 birds. Using a 2 × 2 factorial design, ducklings from each maternal dietary treatment were assigned to a control diet or a 0.16 mg Se/kg supplemented diet from hatch to 2-wk. Compared with Se-deficient diet, maternal diet supplemented with 0.16 mg Se/kg increased the BW of hatchlings (P < 0.01). There were interactions between maternal and progeny diet with 0.16 mg Se/kg in BW of ducklings aged 2 wk and BW gain (BWG) as ducklings from maternal Se/progeny none treatment had the lightest BW and BWG (P < 0.01). Maternal diet with 0.16 mg Se/kg decreased plasma concentration of uric acid and insulin-like growth factor 1 (P < 0.01), and progeny diet supplemented with 0.16 mg Se/kg increased the activities of glutathione peroxidase 3 (GPx3) in plasma and glutathione peroxidase 1 in erythrocyte (P < 0.01). Maternal diet with 0.16 mg Se/kg increased (P < 0.05) the hepatic activity of total superoxide dismutase (T-SOD). Progeny diet supplemented with 0.16 mg Se/kg increased (P < 0.01) hepatic activity of GPx3 and decreased (P < 0.01) the hepatic concentration of malondialdehyde. Interactions were detected between maternal and progeny diet with 0.16 mg Se/kg in hepatic activity of T-SOD and maternal and progeny diet supplemented with Se displayed the highest hepatic activity of T-SOD (P < 0.05). Overall, Se supplementation in the diet of duck breeders and offspring increased the antioxidant capacity of ducklings. Maternal Se supplementation increased the BW of hatchlings, whereas maternal and progeny dietary Se supplementation did not affect the BWG of ducklings aged from 0 to 2 wk. Se supplementation with additional 0.16 mg/kg in the diet of duck breeders and offspring displayed beneficial effects particularly on the antioxidant capacity in ducklings.

Oxidative stress, inflammation, and glycometabolism disorder-induced erythrocyte hemolysis in selenium-deficient exudative diathesis broilers

Selenium (Se) deficiency causes injury of diversified tissues and cells, including livers, hearts, skeletal muscles, and erythrocytes. The aim of the present study is to explore the molecular mechanism of erythrocyte hemolysis due to Se deficiency in broilers. One hundred and eighty broilers (male/female, 1 day old) were randomly divided into two groups and fed with either a normal Se content diet (C group, 0.2 mg Se/kg) or a Se-deficient diet (ED group, 0.008 mg Se/kg) for 45 days. During the trial period of 15-30 days, biological properties such as osmotic fragility, fluidity, phospholipid components of cell membrane, adenosine triphosphatase activities, and antioxidant function of erythrocytes in broilers were examined. Moreover, the messenger RNA (mRNA) expressions of genes associated with inflammation, glycometabolism, and avian uncoupling protein (avUCP) were detected. We found that compared with the C group, hemolysis rate, degree of polarization, and microviscosity of erythrocytes were increased in broilers of the ED group. The composition of erythrocyte membrane lipids was changed. Meanwhile, the antioxidant function of erythrocytes was weakened and mRNA levels of inflammatory genes were stimulated by Se deficiency (p < 0.05). In addition, mRNA expressions of rate-limiting enzymes in glycometabolism were effected and avUCP mRNA level was downregulated (p < 0.05) in the ED group. It has been concluded from the results that oxidative stress, inflammatory response, and glycometabolism disorder lead to erythrocyte hemolysis by changing the structure and function of erythrocyte membrane in ED broilers suffered from Se deficiency.

Harmful Effects and Control Strategies of Aflatoxin B₁ Produced by Aspergillus flavus and Aspergillus parasiticus Strains on Poultry: Review

The presence of aflatoxin B₁ (AFB₁) in poultry diets decreases the hatchability, hatchling weight, growth rate, meat and egg production, meat and egg quality, vaccination efficiency, as well as impairing the feed conversion ratio and increasing the susceptibility of birds to disease and mortality. AFB₁ is transferred from poultry feed to eggs, meat, and other edible parts, representing a threat to the health of consumers because AFB₁ is carcinogenic and implicated in human liver cancer. This review considers how AFB₁ produced by Aspergillus flavus and Aspergillus parasiticus strains can affect the immune system, antioxidant defense system, digestive system, and reproductive system in poultry, as well as its effects on productivity and reproductive performance. Nutritional factors can offset the effects of AFB₁ in poultry and, thus, it is necessary to identify and select suitable additives to address the problems caused by AFB₁ in poultry.

The Protective Effect of Selenium on the Chicken Pancreas against Cadmium Toxicity via Alleviating Oxidative Stress and Autophagy

Cadmium (Cd) is a highly toxic heavy metal that can affect human and animal health. Selenium (Se) is an essential microelement that can protect various organs against toxic heavy metals. Although many studies have investigated the adverse effect of Cd in rats and several other animals, little is known regarding the mechanisms of Cd-induced autophagy in the chicken pancreas and the antagonistic effect of Se on Cd. In the current study, we fed chickens Se, Cd, or Se and Cd supplements to establish the Se and Cd interaction model and to measure the concentrations of Se and Cd in the chicken pancreas. The ultrastructure changes of the chicken pancreas were also observed, and we detected oxidative stress indexes in each group. The expression levels of autophagy-related genes were also examined. We found that Cd exposure could increase the concentration of Cd, the activities of total superoxide dismutase (T-SOD), catalase (CAT), and glutathione peroxidase (GSH-Px); and the total antioxidant capacity (T-AOC) content in the chicken pancreas. The protein expression levels of dynein, Beclin1, LC3-1, LC3-2, and Atg5 were increased and that of TOR was decreased under Cd exposure conditions. However, the changes induced by Cd were significantly alleviated by Se. This study suggested that Cd could accumulate in the chicken pancreas and lead to oxidative stress and autophagy. Se was shown to antagonize Cd toxicity though reducing Cd accumulation, alleviating oxidative stress, and inhibiting autophagy. This study revealed a concrete mechanism for the Se antagonism of Cd and might provide a new clue for the detoxification of Cd poisoning.

MiR-128-1-5p regulates tight junction induced by selenium deficiency via targeting cell adhesion molecule 1 in broilers vein endothelial cells

Vein endothelial cells (VECs) constitute an important barrier for macromolecules and circulating cells from the blood to the tissues, stabilizing the colloid osmotic pressure of the blood, regulating the vascular tone, and rapidly changing the intercellular connection, and maintaining normal physiological function. Tight junction has been discovered as an important structural basis of intercellular connection and may play a key role in intercellular connection injuries or vascular diseases and selenium (Se) deficiency symptoms. Hence, we replicated the Se-deficient broilers model and detected the specific microRNA in response to Se-deficient vein by using quantitative real time-PCR (qRT-PCR) analysis. Also, we selected miR-128-1-5p based on differential expression in vein tissue and confirmed its target gene cell adhesion molecule 1 (CADM1) by the dual luciferase reporter assay and qRT-PCR in VECs. We made the ectopic miR-128-1-5p expression for the purpose of validating its function on tight junction. The result showed that miR-128-1-5p and CADM1 were involved in the ZO-1-mediated tight junction, increased paracellular permeability, and arrested cell cycle. We presumed that miR-128-1-5p and Se deficiency might trigger tight junction. Interestingly, miR-128-1-5p inhibitor and fasudil in part hinder the destruction of the intercellular structure caused by Se deficiency. The miR-128-1-5p/CADM1/tight junction axis provides a new avenue toward understanding the mechanism of Se deficiency, revealing a novel regulation model of tight junction injury in vascular diseases.

Lower Selenoprotein T Expression and Immune Response in the Immune Organs of Broilers with Exudative Diathesis Due to Selenium Deficiency

The objective of the present study was to investigate whether dietary selenium (Se) deficiency would affect the expression of selenoprotein T (SelT) and immune response in the immune organs of broilers. Changes in expression of inflammatory cytokines and oxidative stress response caused by Se deficiency can lead to organism damage, which in turn leads to immune response. Sixty (1-day-old) broilers were divided into the control group and Se-deficiency group. Animal models with exudative diathesis were duplicated in the broilers by feeding them Se-deficient diet for 20 days. After the Se-deficient group exhibited symptoms of exudative diathesis, all the broilers were euthanized, and their immune organs were taken for analysis. The tissues including spleen, bursa of Fabricius, and thymus were treated to determine the pathological changes (including microscopic and ultramicroscopic), the messenger RNA (mRNA) expression levels of SelT and its synthetase (SecS and SPS1), cytokine mRNA expression levels, and antioxidant status. The microscopic and ultramicroscopic analyses showed that immune tissues were obviously injured in the Se-deficient group. The mRNA expression of SelT was decreased compared with that in the control group. Meanwhile, the mRNA expression levels of SecS and SPS1 were downregulated. In the Se-deficient group, the mRNA expression levels of IL-1R and IL-1β were higher than those of three control organs. Additionally, the IL-2 and INF-γ mRNA expression levels were lower than those of the control group. The activity of CAT was decreased, and the contents of H₂O₂ and •OH were increased due to Se deficiency. Pearson method analysis showed that the expression of SelT had a positive correlation with IL-2, INF-γ, SecS, and SPS1 and a negative correlation with IL-1R and IL-1β. In summary, these data indicated that Se-deficient diet decreased the SelT expression and its regulation of oxidative stress, and it inhibited a pleiotropic mechanism of the immune response.

Nutritional requirements of meat-type and egg-type ducks: what do we know?

The demand for duck meat, duck eggs, and associated products is increasing each year. Classic and modern selection programs have been applied to enhance the economic traits of ducks to satisfy the requirements of consumers and enhance the incomes of producers. The nutritional requirements of unselected ducks may not be adequate, however, to fulfill the potential productivity performance of modern birds, including both meat-type and egg-type ducks. In particular, an imbalanced diet is associated with low productive performance and signs of nutritional deficiency (if insufficient nutrients are supplied), as well as with high feed costs and manure problems that reflect flock health and welfare (if excessive nutrients are supplied). Thus, the main aim of this review is to summarize the results of previous studies that estimated the nutrient requirements of meat-type and egg-type ducks in order to evaluate current knowledge and to identify further issues that need to be addressed. In addition, the results obtained in previous studies are compared in order to understand how to lower commercial feed costs, fulfill the genetic potential of selected ducks, protect the environment from pollution, and satisfy the welfare and health needs of ducks.

Determination of Glutathione, Selenium, and Malondialdehyde in Different Edible Mushroom Species

In this study, the amount of reduced glutathione (GSH), oxidized glutathione (GSSG), and malondialdehyde (MDA) were determined by high performance liquid chromatography (HPLC), and selenium was determined by using the fluorescence spectrophotometer in eight different species of edible mushrooms. Brittlegill mushroom (Russula delica), meadow mushroom (Agaricus campestris), dryad's saddle mushroom (Polyporus squamosus), white button mushroom (Agaricus bisporus), Pleurotus spp., ink mushroom (Coprinus atramentarius), ebekari mushroom (slimy) (Elazığ local) and çaşır mushroom (Pleurotus eryngii) (Tunceli local) were used for analysis. The amounts of GSH, GSSG, Se, and MDA with GSH/GSSG ratio in the eight different species of edible mushrooms were observed in between 269.10 ± 16.94-1554.83 ± 58.12 μg/g; 23.55 ± 1.89-841.90 ± 20.03 μg/g; 15.06 ± 1.56-82.10 ± 3.84 μg/g; 5.46 ± 0.50-27.45 ± 2.58 μg/g wet weight and 0.32-41.35, respectively. There is a weak correlation (R ² = 0.389) between MDA and Se, on the other hand, the correlation (R ² = 0.831) between GSH/GSSG ratio and selenium in mushrooms are reasonable well. In a similar manner, there is a weak correlation (R ² = 0551) between GSH/GSSG and MDA ratios in mushrooms. It was found that these edible mushroom species are good source of glutathione (GSH, GSSG), and selenium (Se) in terms of quantities obtained; therefore, it can be said that mushrooms are a rich source of antioxidants.

Selenium Deficiency Affects the mRNA Expression of Inflammatory Factors and Selenoprotein Genes in the Kidneys of Broiler Chicks

The aim of this study was to investigate the influence of Se deficiency on the transcription of inflammatory factors and selenoprotein genes in the kidneys of broiler chicks. One hundred fifty 1-day-old broiler chicks were randomly assigned to two groups fed with either a low-Se diet (L group, 0.033 mg/kg Se) or an adequate Se diet (C group, 0.2 mg/kg Se). The levels of uric acid (UA) and creatinine (Cr) in the serum and the mRNA levels of 6 inflammatory factors and 25 selenoprotein genes in the kidneys were measured as the clinical signs of Se deficiency occurred at 20 days old. The results indicated that the contents of UA and Cr in the serum increased in L group (p < 0.05), and the mRNA levels of the inflammatory factors (NF-κB, iNOS, COX-2, and TNF-α) increased in L group (p < 0.05). Meanwhile, the mRNA levels of PTGEs and HO-1 were not changed. In addition, 25 selenoprotein transcripts displayed ubiquitous expression in the kidneys of the chicks. The mRNA levels of 14 selenoprotein genes (Dio1, Dio2, GPx3, Sepp1, SelH, SelI, SelK, Sepn1, SelO, SelW, Sep15, SelT, SelU, and SelS) decreased, and 9 selenoprotein genes (GPx1, GPx2, GPx4, SelPb, Txnrd1, Txnrd2, Txnrd3, SPS2, and SelM) increased in L group (p < 0.05), but the Dio3 and Sepx1 mRNA levels did not change. The results indicated that Se deficiency resulted in kidney dysfunction, activation of the NF-κB pathway, and a change in selenoprotein gene expression. The changes of inflammatory factor and selenoprotein gene expression levels were directly related to the abnormal renal functions induced by Se deficiency.

Effect of Selenium Deficiency on Nitric Oxide and Heat Shock Proteins in Chicken Erythrocytes

Selenium (Se) deficiency induces various types of diseases, including hemolytic anemia, which is one of the basic pathologies of erythrocyte damage. To investigate the effect of Se deficiency on chicken erythrocytes, we detected the effects of Se deficiency on the nitric oxide (NO) content and the levels of heat shock proteins (Hsps) in chicken erythrocytes, including Hsp27, Hsp40, Hsp60, Hsp70, and Hsp90. One-day-old chickens (180) were randomly divided into two groups, a low-Se group (L group, fed with a 0.008 mg/kg Se diet) and a control group (C group, fed with a 0.2 mg/kg Se diet). Next, erythrocytes were collected at 35 days old, and the NO content, activity of inducible nitric oxide synthase (iNOS), and levels of Hsps (27, 40, 60, 70, and 90) were examined. Compared with the C group, the NO and iNOS levels were significantly higher (P < 0.05), and the Hsps in the mRNA and protein levels were generally higher (P < 0.05) in the L group. Meanwhile, the correlation analysis showed that there were positive correlations between Hsps and NO. Thus, as typical damage biomarkers, NO and Hsps may play special roles in chicken erythrocyte injury by Se deficiency.

The Functions of Antioxidants and Heat Shock Proteins Are Altered in the Immune Organs of Selenium-Deficient Broiler Chickens

Despite increasing evidence indicating the essential involvement of selenium (Se) in the immune system, the effect of Se deficiency on the regulation of oxidative stress and heat shock proteins (Hsps) in broiler chickens is still unclear. In the present study, we established an exudative diathesis (ED) broiler chicken model caused by Se deficiency. We then analyzed histological observations and detected the expression levels of Hsps and antioxidant indexes in immune tissues. The antioxidant function declined remarkably, and most of the Hsp expression levels increased significantly in the spleen, thymus, and bursa of Fabricius of the broiler chicks with ED (except the messenger RNA (mRNA) levels of Hsp27, Hsp40, and Hsp70, which decreased in thymus tissues from the treatment groups); therefore, constitutive oxidation resistance and higher Hsps in broiler chicks with ED caused defects in immune organ morphology and function, as evidenced by abnormal histological structures: red pulp broadening and lymphocytes in the cortex and medulla of the thymic lobule decreased distinctly and distributed loosely. These results underscore the importance of Se in establishing an immune organ microenvironment conducive to normal function.

Effect of Dietary Selenomethionine Supplementation on Growth Performance, Tissue Se Concentration, and Blood Glutathione Peroxidase Activity in Kid Boer Goats

We used 240 kid Boer goats that were divided into six groups. The control group was fed a basal diet containing 0.05 mg of selenium (Se)/kg dry matter (DM). Trial groups received the basal diet supplemented with 0.1, 0.2, 0.3, 0.4, or 0.5 mg Se/kg DM (using a commercial selenomethionine product). Trial groups showed an improvement in growth performance (P < 0.05) despite no change in average daily feed intakes (ADFIs) (P > 0.05) compared to the control group A, quadratic model showed a correlation between glutathione peroxidase activity level in whole blood and dietary Se concentration (R(2) = 0.883, P < 0.04). The best linear model showed that increasing concentrations of Se in the blood (R(2) = 0.968, P < 0.001) and muscle (R(2) = 0.942, P < 0.001) corresponded to increasing Se concentrations in feed. Accumulation of Se in different tissues and organs corresponded to increasing Se concentrations in the diet as well as to the total time goats spent feeding on supplemented diet. Kidney and muscle tissues showed the highest and lowest accumulation of Se, respectively. Thus, Se in goat meat can be increased by adding between 0.1 and 0.5 mg/kg of selenomethionine to the diet of goats.