Calcium Iodate Research Articles

Iodine supplementation of the pregnant dam alters intestinal gene expression and immunoglobulin uptake in the newborn lamb

Excess iodine intake by the pregnant dam reduces lamb serum antibody concentration, specifically immunoglobulin G (IgG). An experiment was conducted to investigate the mechanisms under pinning the reduced serum IgG concentration at 24 h postpartum in the progeny of iodine supplemented dams. Forty-five mature twin bearing ewes (n=15/treatment) were allocated to one of three dietary treatments as follows: basal diet (Control); basal diet plus 26.6 mg of iodine per ewe per day as calcium iodate (CaIO3); or potassium iodide (KI). Ewes were individually housed and fed from d 119 of gestation until parturition. All lambs received colostrum at 1, 10 and 18 h postpartum via stomach tube. At 1 h postpartum lambs from the control and an iodine supplemented treatment (n=10 per treatment from control and CaIO3) were euthanised before colostrum consumption and ileal segments isolated to determine the gene expression profile of a panel of genes identified as having a role in antibody transfer. Preceding euthanasia, lambs were blood sampled for determination of serum IgG, total thyroxine and free tri-iodothyronine concentrations. Progeny of CaIO3 supplemented dams had lower tri-iodothyronine concentrations (P<0.01) at 1 h postpartum and lower serum IgG concentrations (P<0.001) at 24 h postpartum when compared with the progeny of control dams. Iodine (CaIO3) supplementation of the dam increased the relative expression (P<0.05) of the B2M, PIGR and MYC genes in the ileum of the lamb, before colostrum consumption; while the expression of THRB declined when compared with the progeny of C dams (P<0.01). In conclusion, the results of this study show that it is the actual inclusion of excess iodine in the diet of the ewe, regardless of the carrier element, that negatively affects passive transfer in the newborn lamb. This study presents novel data describing the relationship between maternal iodine nutrition and its effect on the thyroid hormone status and subsequent gene expression in the newborn lamb; which results in a failure of passive transfer and a decline in serum IgG concentration.

Gel Casting of Free‐Shapeable Ceramic Membranes with Adjustable Pore Size for Ultra‐ and Microfiltration

The growing demand of reliable high‐performance membrane materials for separation processes requires new simple, straightforward, environmental friendly, sustainable approaches for membrane fabrication. In this study, we present an environmentally friendly gel‐casting, one‐pot process based on ionotropic‐gelation for obtaining alumina membranes. A slurry of alumina particles and the biopolymer alginate, which acts in combination with calcium iodate like a resin, was gelled in a controllable temperature dependent manner. Alumina membranes are obtained by three different shaping routes (extrusion, free‐forming, casting). The suitability of extruded capillaries in a polymer‐ceramic hybrid state (green body) and after sintering (1150°C for 2 h) for potential application in micro‐ and ultrafiltration is evaluated by monitoring the chemical and mechanical stability, permeability and separation behavior. Varying the initial alumina particle size from 200 to 900 nm, membranes with a narrow pore size distribution, predictable and tunable average pore diameters from 70 up to 480 nm and a constant open porosity of ~40%, are obtained. The permeability behavior is tested with fluorescence labeled submicron‐ and nano‐particles. Our novel colloidal processing route represents a very versatile tool for designing and manufacturing ceramic membranes with complex shapes for micro‐ (&gt;0.1 μm) and ultrafiltration (0.1–0.01 μm).

The Influence of High Iodine Intake on Chosen Blood Parameters of Sheep

The objective of the study was to evaluate the influence of high iodine intake in ewes on haematological and biochemical parameters of the blood of ewes and their lambs. Twelve pregnant ewes of the Sumava sheep breed and their newborn lambs were included in the experiment. Control group (A) consisted of 6 ewes with 7 lambs and experimental group (B) comprised 6 ewes with 6 lambs. The feed ration was enriched with calcium iodate by addition of 3 and 5 mg/kg in group A and group B, respectively. The studied parameters in ewes and lambs were haematocrit value, red blood cell count and haemoglobin concentration in blood, concentration of urea and total proteins, and alkaline phosphatase activity in blood plasma. No differences were found out in haematocrit value, red blood cell count, concentration of haemoglobin and total proteins between groups of ewes A and B with their lambs. Urea concentration and alkaline phosphatase activity were higher in ewes of group B and their lambs during the entire experimental period. An increase in the values of urea and alkaline phosphatase in the group of ewes and lambs with higher iodine intake indicates a potential risk of high iodine intake associated with changes in the thyroid activity in ewes and their lambs.

A mechanistic perspective of atmospheric oxygen sensitivity on composite energetic material reactions

Solid energetic composites have been used and studied in standard air environments, yet the contribution of atmospheric oxygen to reactive material combustion has not been investigated. This study experimentally examines the effect of atmospheric oxygen concentration (4% or 93% oxygen) on energy propagation of nanometric aluminum with copper oxide (Al+CuO), iron oxide (Al+Fe2O3), calcium iodate (Al+Ca(IO3)2), and iodine pentoxide (I2O5). In all cases energy propagation was examined in terms of flame speed and higher in the high oxygen environments. However, the convectively dominant reactions showed a smaller percent increase in flame speed mainly attributed to the reaction mechanism.

Synthesis and characterization of calcium iodate, monohydrate crystals grown in silica gel

Simple gel technique was used to grow single crystals of calcium iodate, monohydrate, by single diffusion method. For the growth of crystals, the optimum conditions were established. Morphologies and habit faces like prismatic, prismatic pyramidal crystals were obtained. Few crystals were opaque, some were translucent and some good quality transparent crystals were obtained. Doping of Cu+2 and Fe+3 was done, to study the effect on structure, thermal and nonlinear optical properties. Cell parameters were obtained from the X-ray diffractograms. Structural analysis was done by using FT-IR spectroscopy. TGA and DTA techniques were used to carry out thermal analysis. Nonlinear optical properties were studied using SHG measurements.

Scientific Opinion on the safety and efficacy of Iodine compounds (E2) as feed additives for all species: calcium iodate anhydrous (coated granulated preparation), based on a dossier submitted by Doxal Italia S.p.A.

Scientific Opinion on the safety and efficacy of Iodine compounds (E2) as feed additives for all species: calcium iodate anhydrous (coated granulated preparation), based on a dossier submitted by Doxal Italia S.p.A.

Scientific Opinion on the safety and efficacy of iodine compounds (E2) as feed additives for all animal species: calcium iodate anhydrous, based on a dossier submitted by Calibre Europe SPRL/BVBA

Calcium iodate anhydrous is considered a safe source of iodine for all animal species/categories when used up to the currently authorised maximum content of total iodine in complete feed, with the exception of horses and dogs, for which maximum tolerated levels are 3 and 4 mg I/kg complete feed, respectively. The limited data available on iodine tolerance in cats support a provisional tolerated level of 5 mg I/kg complete feed. Exposure of consumers was calculated in two scenarios applying the currently authorised maximum iodine contents in feed and reduced contents. The iodine content of food of animal origin, if produced taking account of the currently authorised maximum content of iodine in feed, would represent a substantial risk to high consumers. The risk would originate primarily from the consumption of milk and to a minor extent from eggs. The UL for adults (600 μg/day) and for toddlers (200 μg/day) would be exceeded by a factor of 2 and 4, respectively. If the authorised maximum iodine concentrations in feed for dairy cows and laying hens were reduced to 2 and 3 mg I/kg feed, respectively, the exposure of adult consumers would be below the UL. However, iodine intake in highconsuming toddlers would remain above the UL (1.6-fold). Calcium iodate is considered as irritant to the eye, skin and respiratory tract, and a dermal sensitiser. The exposure by inhalation should be avoided. The use of calcium iodate in animal nutrition is not expected to pose a risk to the environment. Calcium iodate is efficacious to meet animal iodine requirements. The FEEDAP Panel recommends that the maximum iodine contents in complete feed be reduced as follows: dairy cows and minor dairy ruminants, 2 mg I/kg; laying hens, 3 mg I/kg; horses, 3 mg I/kg; dogs, 4 mg I/kg; cats, 5 mg I/kg. © European Food Safety Authority, 2013

Scientific Opinion on the safety and efficacy of iodine compounds (E2) as feed additives for all species: calcium iodate anhydrous and potassium iodide, based on a dossier submitted by HELM AG

Calcium iodate anhydrous and potassium iodide are considered safe sources of iodine for all animal species/categories when used up to the currently authorised maximum content of total iodine in complete feed, with the exception of horses and dogs, for which maximum tolerated levels are 3 and 4 mg I/kg complete feed, respectively. The limited data available on iodine tolerance in cats support a provisional tolerated level of 5 mg I/kg complete feed. Exposure of consumers was calculated in two scenarios applying the currently authorised maximum iodine contents in feed and reduced contents. The iodine content of food of animal origin, if produced taking account of the currently authorised maximum content of iodine in feed, would represent a substantial risk to high consumers. The risk would originate primarily from the consumption of milk and to a minor extent from eggs. The UL for adults (600 µg/day) and for toddlers (200 µg/day) would be exceeded by a factor of 2 and 4, respectively. If the authorised maximum iodine in feed for dairy cows and laying hens were reduced to 2 and 3 mg I/kg feed, respectively, the exposure of adult consumers would be below the UL. However, iodine intake in high-consuming toddlers would remain above the UL (1.6-fold). The additives are considered as irritant to the eyes, skin and respiratory tract, and as dermal sensitisers. Exposure by inhalation should be avoided. The use of the additives in animal nutrition is not expected to pose a risk to the environment. The additives are efficacious to meet animal iodine requirements. The FEEDAP Panel recommends that the maximum iodine contents in complete feed be reduced as follows: dairy cows and minor dairy ruminants, 2 mg I/kg; laying hens, 3 mg I/kg; horses, 3 mg I/kg; dogs, 4 mg I/kg; cats, 5 mg I/kg.

Scientific Opinion on the safety and efficacy of iodine compounds (E2) as feed additives for all animal species: calcium iodate anhydrous and potassium iodide, based on a dossier submitted by Ajay Europe SARL

Scientific Opinion on the safety and efficacy of iodine compounds (E2) as feed additives for all animal species: calcium iodate anhydrous and potassium iodide, based on a dossier submitted by Ajay Europe SARL

Properties of Alumina Coagulated Bodies Prepared by Direct Coagulation Casting via High Valence Counter Ions (DCC‐HVCI)

Alumina green bodies were prepared by direct coagulation casting via increasing high valence counter ions (DCC‐HVCI) method. Influence of calcium iodate concentration, coagulation temperature, and the solid loading on the compressive strength of coagulated bodies was investigated. The results show that the wet‐coagulated bodies display higher compressive strength than dried ones. The wet strength is above 2.0 MPa which is about one order higher than that prepared by DCC method, whereas the dried strength is in the range of 1.0 MPa. The wet‐coagulated body shows elastic deformation, whereas the dried body exhibits typical brittle failure behavior. The mechanism of high wet strength obtained by DCC‐HVCI is also proposed. The coagulated bodies prepared from slurries of alumina loading in the range of 50 vol% showed linear shrinkage of 2.6% after drying at 80°C for 24 h. The sample with the powder content of 50 vol% displays a narrow average pore channel size, showing a mean pore diameter of 40 nm. A homogeneous green body and high wet strength can be obtained via the DCC‐HVCI method.

Direct Coagulation Casting of Alumina Suspension by High Valence Counter Ions Using Ca(IO3)2 as Coagulating Agent

A new direct coagulation casting of aqueous alumina suspension was developed via controlled release of high valence counter ions from calcium iodate with increase in the temperature from 55°C to 70°C. The influence of calcium iodate on the rheology of alumina suspension was investigated. A small amount of calcium iodate increased the viscosity of the concentrated alumina suspension at high temperature and finally transformed it into a wet‐coagulated body. The mechanism of coagulation is proposed such as that the solubility of calcium iodate increases with increase in temperature. The high valence Ca2+ ions diffuse into the double electrical layer of alumina particles surface through electrostatic attraction, reduces the zeta potential, hence decreases repulsive force between particles. Also reaction between Ca2+ and citrate leads to insufficient dispersant coverage on the particle surface. Both factors contribute to the coagulation of the suspension. The coagulation time was from 1 to 4 h by maintaining the temperature in the range of 55°C–70°C. The wet‐coagulated bodies prepared from 50 vol% alumina suspension showed a high compressive strength of 2.6–3.2 MPa with uniform microstructure. The relative density of sintered sample is 99.4% at 1550 °C for 2 h with perfect microstructure.

Seasonal variations in plant mineral content and free-choice minerals consumed by deer

The aim of this study was to assess the seasonal differences in mineral contents of plants often consumed by wild red deer located in a fenced game estate, south-eastern Spain. Forage plants were sampled throughout 1 year and analysed for macro and trace mineral concentrations. We also offered a cafeteria set of supplemented minerals to assess whether: (i) intake reflected seasonal reductions in plant content of specific minerals; or (ii) intake of mineral supplements responded to increased deer demand of minerals as a result of greater seasonal needs likely arising from lactation, antler growth or skeletal growth. Although no significant seasonal trend was found in mineral distributions of plants, our study suggested that concentrations of K, Mg, Mn, Na, P, Cu and Zn were usually low in plants available to, and consumed by, deer in the study area. In addition, Cu concentration was marginally deficient when compared with the published requirements for other subspecies of red deer. The cafeteria study showed that free-ranging deer had a strong preference for sodium compounds and zinc sulfate, a much weaker attraction to calcium iodate, and no intake in calcium phosphates, Mg and Fe. Consumption of supplemented minerals by deer was maximum in spring and summer and moderate during autumn and winter. Rather than increasing intake of minerals in response to their content in plants, deer may be responding to increased metabolic requirements during antler growth, late gestation and early lactation. Supplementation of mineral compounds is recommended, particularly in the spring–summer period, when the physiological activity is high.

Influence of various iodine supplementation levels and two different iodine species on the iodine content of the milk of cows fed rapeseed meal or distillers dried grains with solubles as the protein source

Supplementation of animal feed with iodine influences the iodine content of milk and therefore, in addition to salt iodination, provides another possibility for improving the human iodine supply. On the other hand, excessive iodine intake by humans through drinking milk must be avoided. Furthermore, the iodine content of milk varies, depending on the presence of iodine antagonists in feed (e.g., glucosinolates in rapeseed) and the applied iodine species. This study evaluated the impact of various feed iodine supplementation levels up to the permitted maximum level, the effect of applying rapeseed compared with a glucosinolate-free ration, and the impact of 2 different iodine species on the iodine content of milk. A total of 32 dairy cows were divided into 4 groups with 8 animals each. Two groups received distillers dried grains with solubles (DDGS) as the protein source, and the others received rapeseed meal (RSM, 16.5% of total diet). In each case, half the animals received feed supplemented with iodine in the form of potassium iodide, and the other half received feed supplemented with iodine in the form of calcium iodate. Iodine supplementation levels of 0, 0.5, 1, 2, 3, 4, and 5mg/kg of dry matter (DM) were tested in consecutive periods of 21 d each. The milk iodine concentration increased with increasing iodine supplementation of the feed. Rapeseed meal in the ration (0.58mmol of glucosinolates/kg of diet DM) diminished the milk iodine concentration by up to one-half to one-third of the concentration achieved by DDGS. At iodine supplementation levels of 2mg/kg of DM and higher, the differences were significant. The application of iodate predominantly resulted in higher milk iodine concentrations compared with iodide, but not significantly in any period. At the highest tested iodine supplementation (5mg/kg of DM), the milk iodine concentration increased up to 1,464 (iodide) and 1,578μg/kg (iodate) when feeding DDGS and up to 718 (iodide) and 620μg/kg (iodate) in the RSM groups. The carry over of iodine from feed into milk amounted to 30 to 56% when using DDGS, and 11 to 25% when using RSM. The maximum level of iodine currently allowed in the feed of dairy cows in Europe could lead to high milk iodine concentrations. As a result, the Tolerable Upper Intake Level in human nutrition could be exceeded. Therefore, this maximum level needs to be reevaluated. In addition to iodine supplementation, the application of RSM in the ration must be considered when estimating the iodine content of milk.

Effect of various iodine supplementations, rapeseed meal application and two different iodine species on the iodine status and iodine excretion of dairy cows

The aim of the present study was to investigate the impact of various feed iodine supplementations up to the permitted maximum level in the EU, the effect of applying rapeseed meal (RSM) compared to a glucosinolate (GSL) free ration and the impact of two different iodine species (iodide, iodate) on milk, urinary, faecal and blood serum iodine as well as on T 3 and T 4 levels of blood. The results of the milk iodine are not completely shown but partly discussed in this paper. The study was conducted with 32 dairy cows, divided into 4 groups with 8 animals each. In two groups the cows were fed distillers dried grains with solubles (DDGS) as main protein source (16.5% of ration DM), in the other groups rapeseed meal (3.5 mmol GSL/kg) was applied. In each case half of the animals received feed with iodine in the form of potassium iodide, the other half as calcium iodate. Iodine supplementations of 0, 0.5, 1, 2, 3, 4 and 5 mg/kg DM were tested in consecutive periods of 21 days each. The supplementary iodine increased iodine contents of serum, urine and faeces. RSM application resulted in consistently higher iodine contents in the mentioned matrices just displaying significant differences at high supplementation levels. When feeding DDGS, at high iodine supplementations iodide caused higher serum and faecal iodine than iodate. Besides, the iodine species showed no consistent impact on the tested parameters. At the highest tested iodine supplementation (5 mg/kg DM) in the experimental groups (DDGS/iodide, DDGS/iodate, RSM/iodide, RSM/iodate) the iodine concentration of serum amounted to 234, 157, 334 and 361 µg/l, of urine to 1134, 1020, 2341 and 2513 µg/l and of faeces to 673, 354, 715 and 790 µg/kg fresh matter. At the same supplementation level T 4 was significantly lowered. No impact was shown for the RSM application and the iodine species on T 3 and T 4. The results of the present study indicate that high iodine intakes not only cause strong increases in milk and urinary iodine but also lead to a considerable rise of iodine excretion via faeces. RSM in feed causes a shift of iodine normally excreted via milk to an excretion via urine and faeces accompanied by higher serum iodine.

Responses of Broilers under Cold Conditioning (15ºC) to Dietary Triiodothyronine and Iodine Combined to Antioxidants (Selenium and Vitamin C)

Summary This experiment was conducted to determine the influence of dietary antioxidants (selenium (Se) and vitamin C), and triiodothyronine (T3) to iodine on biochemical parameters, malondialdehyde (MDA), catalase (CAT) in broilers exposed cold. In the study, 150, one-day-old, broiler chicks (Ross 308) were used. Chicks were randomized into 1 control and 4 treated groups each containing 30 birds and each experimental group comprised 3 replicates of 10 birds. The experimental groups were as follow: control was fed with basal diet; group I was fed with basal diet supplemented with 1 mg/kg selenium as sodium selenite plus 2 mg/kg iodine as calcium iodate; group II was fed with basal diet supplemented 1 mg/kg selenium plus 1 mg/kg T3; group III was fed with basal diet supplemented with 250 mg/kg vitamin C as ascorbic acid plus 1 mg/kg iodine; group IV was fed with basal diet supplemented with 250 mg/kg vitamin C plus 1 mg/kg T3. Plasma T3, triglyceride and SGPT were significantly different among the groups. MDA level in heart tissue of control group was found significantly higher than those of other groups (P<0.01). MDA levels in liver (P<0.01) and abdominal fat (P<0.001) tissues of control and group I were determined significantly higher than those of other groups, whereas MDA level in lung tissue was similar found in all groups. The CAT activity of liver of control and group I was found significantly the highest (P<0.001). Results showed that cold exposure in broilers induced oxidative damage in tissues, but this damage decreased partly in supplement groups, except group I.

Effect of Different Levels of Rapeseed Meal Supplemented with Calcium Iodate on Performance, Some Carcass Traits, and Thyroid Hormones of Broiler Chickens

In a completely randomized design with 3*3 factorial arrangements and 4 replicates, 360 day-old Ross male broiler chickens were used to evaluate the effect of different levels of a locally grown rapeseed meal (RSM) supplemented with iodine on performance, organs weight and thyroid hormones of broiler chickens. The RSM was used at the levels of 0.0 (control), 7.5 and 15.0 percent for 7 weeks. The iodine levels added into the diets were 0.35 (NRC, 1994 recommendation, control), 0.75 and 1.05 mg/Kg. Feed intake and feed to gain ratio were affected by added levels of RSM during the starter (0-21 d), grower (21-42), finisher(42-49) and overall (0-49 d) feeding periods (P<0.05). Body weight gain was not affected by treatments in any periods. Added high levels of RSM significantly increased the relative weights of liver, spleen (P<0.05) and decreased the weights of abdominal fat pad (P<0.05). Adding levels of RSM were also significantly increased the concentration of serum tri-idotyronine (T ) at 42 days of age and the concentration 3 of serum thyroxin (T ) at 21 days of age (P<0.05), while adding iodine into the diets had no significant effect 4 among treatments. Thyroid-stimulating hormone (TSH) was not significantly affected by adding RSM into the diets at 21 and 42 days of age. Under the conditions of this study it was concluded that adding RSM into the diets of broilers decreases their performance. Spite the non significant effect of iodine on performance of broilers, due to the presence of glucosinolates in RSM, use of more iodine needs to be considered.

CALCIUM IODATE???ANOTHER EFFECTIVE BLOCKER OF RADIOIODINE UPTAKE BY THE THYROID GLAND

KI and KIO3 are the commonly used prophylactic drugs for the protection of thyroid glands against radioiodine. In this study, we have demonstrated the use of another iodine containing salt, calcium iodate [Ca(IO3)2], as an effective blocker of radioiodine uptake by the thyroid gland in rats. Ca(IO3)2 is permitted by the FDA as a food additive and is "generally regarded as safe" (GRAS, CFR No.1206). We have also compared the efficacy of Ca(IO3)2 with KIO3 in blocking thyroidal uptake of radioiodine, which could be important considering the better shelf life of Ca(IO3)2. Laboratory rats were administered 131I and stable iodide in the form of KIO3 or Ca(IO3)2 was given orally, 2 h after the administration of 131I. All the animals were monitored for whole body retention (WBR) of 131I, at 24 h and further for 14 d. The results of the present study provide us with evidence that Ca(IO3)2 can serve as another promising radioiodine blocker, and is as equipotent as KI/KIO3 in protecting the thyroid gland. We have not found any studies that examined the property of Ca(IO3)2 in blocking radioiodine uptake by the thyroid gland and the present study is an attempt in this direction.

Effects of supplementary iodine on the performance and egg traits of laying hens

1. This experiment was carried out to determine the effects of dietary iodine supplementation on the performance and egg traits of laying hens. A total of 600 SHSY type brown layers aged 21 weeks of age were chosen at random from a large flock. They were randomly distributed into 30 pens at 20 hens per pen. Each treatment comprised 6 replicates of 20 layers in groups of 5 birds. The diets were supplemented with 0, 3, 6, 12 and 24 mg/kg iodine as calcium iodate. The experimental period lasted 30 weeks. 2. There were no significant differences among the groups in body weight, food consumption, egg production, food consumption per kg eggs, eggshell index, eggshell breaking strength, shell thickness or egg yolk index. 3. Supplementation of the diet with 12 mg/kg iodine increased food consumption per dozen eggs compared to the groups fed on diets supplemented with 0 and 6 mg/kg iodine. 4. Egg weight was less in groups fed on diets supplemented with 12 and 24 mg/kg iodine than in the group receiving no iodine supplementation. 5. Iodine supplementation to provide 12 and 24 mg/kg reduced egg albumen index and egg Haugh units. 6. There were no significant differences among the groups in egg cholesterol and egg yolk cholesterol contents. 7. The iodine concentrations in egg yolk, egg albumen and whole egg increased with increased iodine supplementation. 8. As a result, the 3 and 6 mg/kg iodine supplementation of diet could be used to enrich the eggs with iodine without any adverse effect on performance and egg traits.

Application of sodium alginate gelation to aqueous tape casting

A novel gel tape casting process has been developed by introducing sodium alginate into a conventional aqueous tape casting slurry. The process makes use of a binder system consisting of 1 wt-% sodium alginate and 20 vol.-% styrene acrylic latex to prepare the tape casting slurry. Sodium alginate can react with calcium iodate to form a three-dimensional network at room temperature, and with the ceramic particles held in this three-dimensional network, the slurry can be consolidated to form green tapes. This allows the need for the special drying procedure that is usually a critical step in tape casting to be avoided. Styrene acrylic latex was used to improve the flexibility of the green tapes. Compared with tapes obtained by conventional aqueous tape casting, more homogeneous microstructure was obtained by this process.

Fabrication of alumina green body through gelcasting process using alginate

In the present work, we studied the addition of sodium alginate, a natural innoxious polymer, to coagulate alumina slurry in the fabrication of an Al 2O 3 green body. Calcium iodate was added into the alumina suspension that was dispersed in a sodium alginate solution. The slurry was stable at room temperature but it solidified with increasing temperature. A slurry of 50 vol.% alumina ceramic powder, 1 wt.% calcium iodate and 1 wt.% sodium alginate solidified after being heated at 60 °C for 1 h. In addition to this process, a chelator was used to control the gelation behavior. Associated with the effect of the chelator, the consolidation reaction rate was delayed to longer than 30 min. The gelling properties of the sodium alginate solution and the resultant alumina slurry were analyzed. The rheological behavior of the slurry was examined. Appropriate forming processes were determined. Near-net-shaped green bodies were produced. The resultant green body has uniform structure and smooth surface, and the bonding strength is as high as 8.0 MPa.