Molecular characterization of a large cohort of mucopolysaccharidosis patients: Iran Mucopolysaccharidosis RE-diagnosis study (IMPRESsion).

Mucopolysaccharidoses (MPSs) are rare, heterogeneous inborn errors of metabolism (IEM) diagnosed through a combination of clinical, biochemical, and genetic investigations. The aim of this study was molecular characterization of the largest cohort of Iranian MPS patients (302 patients from 289 unrelated families), along with tracking their ethnicity and geographical origins. 185/289 patients were studied using an IEM-targeted NGS panel followed by complementary Sanger sequencing, which led to the diagnosis of 154 MPS patients and 5 non-MPS IEMs (diagnostic yield: 85.9%). Furthermore, 106/289 patients who were referred with positive findings went through reanalysis and confirmatory tests which confirmed MPS diagnosis in 104. Among the total of 258 MPS patients, 225 were homozygous, 90 harbored novel variants, and 9 had copy number variations. MPS IV was the most common type (34.8%) followed by MPS I (22.7%) and MPS VI (22.5%). Geographical origin analysis unveiled a pattern of distribution for frequent variants in ARSB (c.430G>A, c.962T>C [p.Leu321Pro], c.281C>A [p.Ser94*]), GALNS (c.319G>A [p.Ala107Thr], c.860C>T [p.Ser287Leu], c.1042A>G [p.Thr348Ala]), and IDUA (c.1A>C [p.Met1Leu], c.1598C>G [p.Pro533Arg], c.1562_1563insC [p.Gly522Argfs*50]). Our extensive patient cohort reveals the genetic and geographic landscape of MPS in Iran, which provides insight into genetic epidemiology of MPS and can facilitate a more cost-effective, time-efficient diagnostic approach based on the region-specific variants.

Growth retardation among children in southern Iran: a 7-year population based cohort study.

BACKGROUND: Growth retardation is a common health problem, which requires early prevention and detection. This study was conducted to define the approximate age at which stunting starts among the Iranian boys and girls. METHOD: The second phase of a population-based retrospective cohort nested case-control study on 400 children who were followed from birth to 7 years of age. This study was performed to define the pattern of growth among stunted and normal children and to reveal the age at which stunting starts in each gender. RESULTS: Of the selected participants, 53% were girls. Also, about 18% of the children registered by the selected health centers were defined as stunted (under the 3rd percentile of the corresponding sex-age NCHS/WHO growth reference). For boys, the height was relatively similar between the two groups until the age of 6 months at which the difference in height between normal and stunted children starts to become significantly large (difference = 0.70 cm, P = 0.04). For girls, height in the two groups is relatively similar until the age of 9 months at which the difference starts to become significantly large (difference = 0.97 cm, P = 0.01). No significant difference in the weight of the girls was observed between the normal and stunted groups during the study period (difference = 283.21 g, P > 0.05). However, boys from the stunted group were lighter since almost the same time that they started to become significantly shorter (difference = 1265.19 g, P = 0.001). CONCLUSIONS: Soon after birth (at about the 6 months of age), the growth pattern of some (stunted) children starts to stumble and divert from normal. The sixth month of age is the age at which mothers start weaning with withdrawing breast milk and start supplementary foods and adult diet. A specially designed study is needed to understand the actual reason for observing such a phenomenon among Iranian children.

International clinical guidelines for the management of phosphomannomutase 2-congenital disorders of glycosylation: Diagnosis, treatment and follow up.

Phosphomannomutase 2 (PMM2-CDG) is the most common congenital disorder of N-glycosylation and is caused by a deficient PMM2 activity. The clinical presentation and the onset of PMM2-CDG vary among affected individuals ranging from a severe antenatal presentation with multisystem involvement to mild adulthood presentation limited to minor neurological involvement. Management of affected patients requires a multidisciplinary approach. In this article, a systematic review of the literature on PMM2-CDG was conducted by a group of international experts in different aspects of CDG. Our managment guidelines were initiated based on the available evidence-based data and experts' opinions. This guideline mainly addresses the clinical evaluation of each system/organ involved in PMM2-CDG, and the recommended management approach. It is the first systematic review of current practices in PMM2-CDG and the first guidelines aiming at establishing a practical approach to the recognition, diagnosis and management of PMM2-CDG patients.

Splicing defect in FKBP10 gene causes autosomal recessive osteogenesis imperfecta disease: a case report.

BACKGROUND: Osteogenesis imperfecta (OI) is a group of connective tissue disorder caused by mutations of genes involved in the production of collagen and its supporting proteins. Although the majority of reported OI variants are in COL1A1 and COL1A2 genes, recent reports have shown problems in other non-collagenous genes involved in the post translational modifications, folding and transport, transcription and proliferation of osteoblasts, bone mineralization, and cell signaling. Up to now, 17 types of OI have been reported in which types I to IV are the most frequent cases with autosomal dominant pattern of inheritance. CASE PRESENTATION: Here we report an 8- year- old boy with OI who has had multiple fractures since birth and now he is wheelchair-dependent. To identify genetic cause of OI in our patient, whole exome sequencing (WES) was carried out and it revealed a novel deleterious homozygote splice acceptor site mutation (c.1257-2A > G, IVS7-2A > G) in FKBP10 gene in the patient. Then, the identified mutation was confirmed using Sanger sequencing in the proband as homozygous and in his parents as heterozygous, indicating its autosomal recessive pattern of inheritance. In addition, we performed RT-PCR on RNA transcripts originated from skin fibroblast of the proband to analyze the functional effect of the mutation on splicing pattern of FKBP10 gene and it showed skipping of the exon 8 of this gene. Moreover, Real-Time PCR was carried out to quantify the expression level of FKBP10 in the proband and his family members in which it revealed nearly the full decrease in the level of FKBP10 expression in the proband and around 75% decrease in its level in the carriers of the mutation, strongly suggesting the pathogenicity of the mutation. CONCLUSIONS: Our study identified, for the first time, a private pathogenic splice site mutation in FKBP10 gene and further prove the involvement of this gene in the rare cases of autosomal recessive OI type XI with distinguished clinical manifestations.

Stunting and its associated factors among 6-7-year-old children in southern Iran: a nested case-control study.

OBJECTIVE: Height-for-age shorter than 3th percentile or 2 sd below the median of the National Center for Health Statistics/WHO growth reference is known as stunting. The present study aimed to measure the association of several factors with stunting in a cohort born from 2009 to 2010 in Shiraz, Iran.Design/Setting/SubjectsNested case-control study conducted on pre-school children in 2016. Participants were 200 children suffering from stunting (case group) and 200 children with normal height (control group). RESULTS: Results of multivariable logistic regression analysis suggested a significant relationship (adjusted OR; 95 % CI) between stunting and mother's occupation (employed v. housewife: 3·58; 1·73, 7·39) and chronic diseases (yes v. no: 2·93; 1·25, 6·88). In addition, significant associations were found between family income (30 million Rials: 5·63; 2·46, 12·87), diary consumption (very little v. high: 5·93; 1·74, 20·18) and animal protein in diet (low v. very high: 2·42; 1·13, 5·19) and stunting among children. Also, chance of stunting was inversely associated with birth interval (<2 years v. first child: 3·13; 1·45, 6·76) and duration of exclusive breast-feeding (18-24 months v. formula only or breast-feeding for <18 months: 0·53; 0·30, 0·92). CONCLUSIONS: Mothers being housewife, possibly due to having more time to take care of their children, childhood diseases and consumption of dairy foods are strong and modifiable factors which can positively affect Iranian children's stature. Higher family income is another important factor in stunting but under less parental control.

A New Mutation Causing Severe Infantile-Onset Pompe Disease Responsive to Enzyme Replacement Therapy.

Pompe disease (PD), also known as "glycogen storage disease type II (OMIM # 232300)" is a rare autosomal recessive disorder characterized by progressive glycogen accumulation in cellular lysosomes. It ultimately leads to cellular damage. Infantile-onset Pompe disease (IOPD) is the most severe type of this disease and is characterized by severe hypertrophic cardiomyopathy and generalized hypotonia. Mutations in the acid alpha-glucosidase (GAA) gene, located at locus 17q25.3, are responsible for the disease leading to reduced activity of the acid alpha-glucosidase enzyme. To date, approximately 400 pathogenic mutations have been reported in the GAA gene. The aim of this study is to report a novel nonsense mutation in exon 4 of the GAA gene in an Iranian child suffering from IOPD. The patient was a female neonate with hypertrophic cardiomyopathy and a positive family history of IOPD. After definite diagnosis, enzyme-replacement therapy (ERT) was started for the patient, who was 2 months old. Now at the age of 20 months, she has had good growth and development and her echocardiographic parameters are within the normal range. This report shows that IOPD patients with this mutation can be treated with ERT successfully.

Evaluation of bone mineral density in patients with hemoglobin H disease.

OBJECTIVES: This study was conducted to assess bone mineral density (BMD) and bone mineral content (BMC) of patients with hemoglobin H (HbH) disease. METHODS: BMD and BMC were measured by dual energy X-ray absorptiometry of the lumbar spines and femur neck in 21 patients with Hb H disease over the age of 10 years. An association of BMD with sex, age, hemoglobin, calcium, phosphorus, and serum ferritin level was also evaluated. RESULTS: Prevalence of BMD below the expected range for age in the lumbar spine and femur neck region in patients with HbH disease were 33.3 and 14.3 %, respectively. Lumbar BMD was significantly lower in the patients compared to healthy individuals (median (min-max) 0.725 (0.595-0.924) vs. 1.061 (0.645-1.238), P < 0.001)). There was no significant relationship between BMD in the lumbar and femur neck with any of the evaluated variables (P value >0.05). CONCLUSION: Data regarding bone density in HbH disease is limited; osteoporosis as a common complication of ß-thalassemia intermedia syndrome should be considered even in HbH which shows its prevalence is less than ß-thalassemia intermedia.

CYP21A2 Gene Analysis in Southern Iranian CAH Patients and a Brief Review of the Mutation Spectrum.

Background: CYP21A2 gene mutations are responsible for more than 95% of Congenital Adrenal Hyperplasia (CAH) disorders with autosomal recessive inheritance. Most of these pathogenic mutations originate from the CYP21A1P, a neighboring pseudogene with 98% homology, due to unequal crossing over or gene conversion events. Mutation identification of the gene could be beneficial for accurate diagnosis and outcome prediction. Methods: Twelve unrelated patients with CAH diagnosis were recruited for genetic counseling. To ensure distinct amplification of the CYP21A2 gene rather than its pseudogene, the complete sequence of the gene was amplified through two overlapping fragments by specific primers. The entire sequences were screened by direct Sanger sequencing using new sequencing primers. Results: Only two pathogenic point mutations were identified. The c.293-13C>G, also known as In2G, and the c.955C>T mutations were found in 37.5 and 33.3% of alleles, respectively. One patient showed homozygous gene deletion. We also reviewed recent reports on CYP21A2 gene mutations in Iran. Conclusion: Evaluating the ethnicity-specific gene mutation data is significant for populations with diverse ethnic groups including the Iranian population. Although several common mutations have been reported as causative mutations among CAH patients, identifying only two common point mutations in Fars province would help prioritize exon sequencing and reduce the cost and time of genotyping.

Evaluation of the safety and efficacy of biosimilar recombinant growth hormone in children with growth hormone deficiency: non-inferiority, randomized, parallel, multicentric and Phase III trial.

OBJECTIVES: This study is designed in order to compare the efficacy and safety of recombinant human growth hormone (rhGH) with the reference brand. METHODS: According to the inclusion criteria, 85 people in 13 Iranian centers were randomly selected to receive biosimilar Somatropin (Somatin®) (44 people) and reference Somatropin (Norditropin®) (41 people) at a dose of 35 µg/kg/d, seven days/week for 12 months. The primary outcomes included height velocity (HV) was measured during 12 months of treatment. RESULTS: The two intervention groups' Height changes were similar. The mean HV was 10.96 cm/year in the biosimilar group and 10.05 cm/year in the reference groups after 12 months. Estimates of the lower bounds of 95% CI for mean height differences in the biosimilar intervention group compared to the reference intervention group did not exceed the 2 cm margin. Therefore, the non-inferiority of biosimilar intervention compared to the brand product is verified. Common ADRs in both groups were nausea in two patients (2.4%), diarrhea in two patients (2.4%), increased body temperature in one patient (1.2%), and headache in one patient (1.2%). CONCLUSIONS: The finding of this study indicated that Somatin® and Norditropin® have comparable efficacy and safety profiles. CLINICAL TRIAL REGISTRATION: www.IRCT.irIRCT20171122037571N1.

Review of the training program of pediatric residents: is it appropriate for their future careers?

BACKGROUND: Training of pediatric residents is a dynamic process which should be changed as the nature andepidemiology of pediatric diseases change. In this study, we compared the training program of the pediatric residentswith the disorders of the pediatric patients who had referred to pediatric offices. METHODS: The study was conducted in pediatric offices in Shiraz, South of Iran. The main complaints of all thepatients who were referred to these offices in the first 3 days of the four seasons of the year were recorded. Finally,descriptive statistics was used to determine the frequency of different complaints among these patients. RESULTS: There are 58 Pediatrics offices in Shiraz and 37 offices completed the questioners (64%). The mostfrequent complaints of the patients were related to infections, especially respiratory and gastrointestinal ones.Nutritional and growth problems were other frequent complaints. Nonetheless, a high number of the patientswere referred due to skin, eye, or ear problems or for check up of the baby. CONCLUSION: There is an important training-practice problem in the curriculum of pediatric residents. Thus, wesuggest decreasing the periods of inpatient subspecialty training and increasing the period of outpatient dermatology,ophthalmology, otolaryngology, and well-baby clinics.

Determination of prediction equations for apparent metabolizable energy corrected for nitrogen of corn gluten meal and canola meal in broilers.

The objectives of this experiment were to determine the AMEn content of different samples of corn gluten meal (CGM) and canola meal (CM) by a reference diet method and to develop prediction equations based on the chemical composition to estimate the AMEn value of CGM and CM in broilers. A total of 300 one-day-old male broiler chicks were randomly assigned to fifteen treatments (14 experimental diet and 1 reference diet) with 4 replicates of each with 5 birds per replicate. At first, birds were fed a starter diet from 0 to 10 d of age, and then, a grower diet from 11 to 23 d of age. To determine the AMEn content, the test diet consisted of 60% reference diet, 38% each test CGM or CM, and 2% minor ingredients. To adaptation, the broilers were fed experimental diets for 4 d, and then feces were collected on 28 d. The gross energy values and chemical compositions among the CGM and CM from different origins were significantly different. The AMEn values of the CGM samples varied from 3,123 to 3,918 kcal/kg, and for the CM, the range was from 1,578 to 2,109 kcal/kg. At the end of the experiment, data were analyzed with SPSS software, and a regression equation was obtained based on the chemical composition. The best equations were selected based on the standard of prediction and regression adjusted R2. The equation, AMEn = 49.196 × CP + 80.87 × EE (SEP 180.99; adjusted R2 0.97), was selected to predict the AMEn value of CGM, and the equation, AMEn = 631.55 × EE + 16.716 × CP (SEP 55.3; adjusted R2 0.94), was selected to predict the AMEn value of CM.

Effects of Different Levels of Dietary Zinc-Threonine and Zinc Oxide on the Zinc Bioavailability, Biological Characteristics and Performance of Honey Bees (Apis mellifera L.).

The experiment was conducted to investigate the effect of supplementary different levels of zinc-threonine (Zn-Thr) and zinc oxide (ZnO) on the Zn bioavailability, biological characteristics and performance of honey bees (Apis mellifera L.). The experiments were carried out with seven treatments in a completely randomized design with five replicates for each treatment. During the experiment, groups were fed a basal diet without extra zinc (10.4 mg Zn/kg diet), and it was used as the control diet and 3 levels of 20, 40, and 60 mg Zn/kg were added to the diet by ZnO and Zn-Thr sources. The results showed that different levels of organic Zn significantly increased Zn and Fe content in the carcass of caged bees compared to different levels of inorganic Zn and control groups. Also, honey bees fed with levels of 40 and 60 mg Zn/kg Zn-Thr supplementation significantly had lower Malondialdehyde (MDA) concentration and higher ash content, protein content, superoxide dismutase (SOD) activity in their tissues. In addition, they showed more life span, feed intake, population, brood rearing, and hive weight gain (p < 0.05). Totally, the results of the present experiments revealed that diets supplied with organic Zn compared to inorganic Zn play significant roles in the improvement of Zn bioavailability, biological characteristics, and performance in honey bees.

The effect of yoga therapy directed by virtual training on depression of adolescent girls with type 1 diabetes: a randomized controlled trial.

Background: Recently, the depression-alleviating impact of yoga therapy was documented among patients with type 2 diabetes; nonetheless, whether this consequence is similar in individuals with type 1 diabetes (T1D) is still unclear. Therefore, this trial sought to investigate the potential impact of yoga therapy on the depression of adolescents with T1D. Methods: This randomized controlled trial recruited 62 girls with T1D, aged 12-17 years, from January to June 2020. The participants were randomly allocated to equal experimental and control arms (31 per group) through a block randomization approach. The routine care was implemented in two study arms, while the experimental arm additionally received yoga therapy directed by virtual training for eight consecutive weeks (one session per week). Maria Kovacs Children's Depression Inventory was completed at baseline and the end of the 8-week intervention. Results: The mean of the depression total score was significantly lower in the experimental arm in comparison with the control arm at the trial end (9.38 ± 8.44 vs. 12.77 ± 6.96, p = 0.014). Also, the reduction in mean change from the baseline to the trial end was significantly more in the experimental arm (- 5.25 ± 1.13 vs. - 0.80 ± 1.00, p = 0.013). Conclusions: The administration of yoga therapy directed by virtual training seems to be potentially effective in reducing depression among adolescent girls with T1D. However, further long-term trials with a larger sample size are needed to shed light on the obtained findings and address the intervention's efficacy on glycemic outcomes. Supplementary Information: The online version contains supplementary material available at 10.1007/s40200-023-01245-x.

Inborn Errors of Metabolism Associated With Autism Among Children: A Multicenter Study from Iran.

OBJECTIVE: This study aimed to find the common inborn errors of metabolism in Iranian patients with autism spectrum disorder. METHODS: In this cross-sectional multicenter study, 105 children and adolescents with autism spectrum disorder from six centers in different cities of Iran were enrolled between August, 2019 and October, 2020. Metabolic screening, including measuring plasma levels of amino acids, acylcarnitines, creatine, and guani-dinoacetate, and urinary levels of organic acids, purines, and pyrimidines was performed. Other data, including age, parental consanguinity, history of seizure, developmental mile-stones, and physical examination, were also recorded. RESULTS: An inborn error of metabolism was found in 13 (12.4%) patients. Five patients (4.8%) had cerebral creatine deficiency syndrome, 4 (3.8%) had arginine succinate aciduria, 2- methylbutyryl glycinuria, short-chain acyl-CoA dehydrogenase deficiency, and combined methylmalonic aciduria/malonic aciduria. There was a strong association between positive meta-bolic evaluation and parental consanguinity, history of seizures, microcephaly, and delayed development. CONCLUSIONS: Our results suggest that metabolic screening should be performed in the cases of autism associated with parental consanguinity, developmental delay, and a history of seizures. The assays to be considered as a screening panel include plasma or blood amino acids, acylcarnitines, creatine and guanidinoacetate, and urinary levels of organic acids.

Evaluation of an Innovative Zn Source on Feed Efficiency, Growth Performance, Skin and Bone Quality of Broilers Suffering Heat Stress.

One thousand two hundred male broilers were used to evaluate the effect of different dosages of HiZox® on feed efficiency, growth performance and bone quality of broilers suffering from heat stress. A completely randomized design was used, with four treatments and ten replicates. Basal corn−soybean meal diets supplemented with 75, 100 and 125 mg/kg zinc from HiZox and 100 mg/kg zinc from regular ZnO were used to make four treatments. Heat stress was induced after the third week by keeping house temperature between 28−34 °C, from 1 pm until 5 pm. The body weights of the birds that received the diet supplemented with HiZox or ZnO showed no significant difference at 7 and 14 days. Body weight of heat stressed birds fed diets containing different levels of HiZox or ZnO were not different at 28 and 42 days of age. In comparison to the Ross 308 management guide, induced heat stress diminished body weight and feed intake by approximately 17 and 21%, respectively. At 28 days, chickens who received 125 mg/kg Zn from Hizox had better feed efficiency (p < 0.05). The mortality rate of heat-stressed male broiler chickens who received different dosages of HiZox was 2.85% less than that of the regular ZnO group (p < 0.06). The results showed that addition of HiZox to the diet of male broiler under heat stress doubled the skin resistance during feather plucking in the slaughter plant and improved carcass quality (p < 0.07). Tibia breaking strength, included elongation and extension were improved by consumption of a diet supplemented with 75 mg HiZox/kg (p < 0.09). The HiZox-75 fed broilers required higher amounts of energy (MJ) for tibia breaking at break and peak points at 42 days (p < 0.09; p < 0.07). Jejunum Zn concentrations reflected the quantity of ingested Zn (p < 0.0001). Gizzard Zn solubility was dependent on dietary treatment (p < 0.03). Solubility of Zn in the gizzard of chickens who received HiZox was higher (about 30%) than broilers fed regular ZnO. In conclusion, Zn from HiZox was more efficient in decreasing heat stress mortality, increasing skin resistance and bone breaking strength compared to a regular ZnO source.

Carbulin: A Comprehensive Mobile Application for Advanced Carbohydrate Counting and Diet- and Insulin-Regimen Planning for Type 1 Diabetic Patients.

Nowadays, the introduction of the so-called 'diabetes technology', either hardware/device or software, to different aspects of day-to-day living in patients with diabetes aims to improve blood glucose control and various lifestyle features. The coordination of vast context of diabetes education/training, particularly in the area of medical nutrition therapy, is considered as a great concern. On the other hand, Iranian food culture consists of a set of traditional dietary patterns and food consumption habit. The study was aimed to develop "the Comprehensive Mobile Application of Advanced Carbohydrate Counting and Diet- and Insulin-Regimen Planning" to help type 1 diabetic patients, improving their health status. The programming language of Kotlin, JavaScript, Node JS, and HTML5 was used for the mobile app development. The app was developed with the following abilities: 1) educating users on different aspects of disease control including, updated general treatment guidelines on physical activity, medical nutrition and insulin therapy, stress management, and the patient's specific goals and dietary needs, 2) performing advanced carbohydrate counting using both picture-represented and kitchen-scale of carbohydrate foods as well as traditional Iranian foods, 3) recommending the patient's specific insulin dose, either short- or rapid-acting, based on the carbohydrate content of the selected meal or the selected amount of Iranian foods, 4) recommending the personalized insulin dose needed for decreasing the high blood glucose levels, and 5) performing 3 and 4 simultaneously. Developing Carbulin was an effort to increase type 1 diabetes self-management using the traditional Iranian dietary pattern and menu.

The frequency of CD4+ and CD8+ circulating T stem cell memory in type 1 diabetes.

INTRODUCTION: The frequencies and functions of T stem cell memory (TSCM) subsets vary in autoimmune diseases. We evaluated the frequencies of CD4+ and CD8+ TSCM subsets as well as their PD-1 expression levels in patients with T1D. METHODS: Blood samples were collected from new case (NC) (n = 15), and long-term (LT) (n = 15) groups and healthy controls (n = 15). Five subsets of T cells including TCM(CD4+ /CD8+ CCR7+ CD45RO+ CD95+ ), TCMhi (CD4+ /CD8+ CCR7+ CD45ROhi CD95+ ), TEM(CD4+ /CD8+ CCR7- CD45RO+ CD95+ ), TSCM(CD4+ /CD8+ CCR7+ CD45RO- CD95+ ), and T naive (CD4+ /CD8+ CCR7+ CD45RO- CD95- ) were detected by flow-cytometry. RESULTS: The frequency of CD4+ TSCM was higher in NC patients than LT patients and controls (p < .0001 and p = .0086, respectively). A higher percentage of the CD8+ T naive cells was shown in NC patients as compared with LT and healthy individuals (p = .0003 and p = .0002, respectively). An increased level of PD-1 expression was observed on the CD4+ TCM and TCMhi cells in LT patients as compared with healthy controls (p = .0037 and p = .0145, respectively). Also, the higher PD-1 expression was observed on the CD8+ TCM and TCMhi in NC and LT patients as compared with controls (p = .0068 and p < .0001; p = .0012 and p = .0012, respectively). CONCLUSION: Considering TSCMs' capacities to generate all memory and effector T cells, our results may suggest a potential association between the increased frequencies of TSCMs and T1D progression.

Comparison the Zn-Threonine, Zn-Methionine, and Zn Oxide on Performance, Egg Quality, Zn Bioavailability, and Zn Content in Egg and Excreta of Laying Hens.

The experiment was conducted to investigate the effect of supplementary zinc-threonine (Zn-Thr), zinc-methionine (Zn-Met), and zinc oxide (ZnO) on the laying performance, egg quality, Zn content in egg and excreta. One hundred and sixty hens (Hy-Line W36) were randomly divided into 10 treatments with 4 replications of 4 hens each. During the first 4 weeks, groups were fed a corn-soy basal diet without extra zinc (30.3 mg Zn/kg diet) to depletion storage zinc from the body and it was used as the control diet. During the ensuing 10 weeks from 36 to 45 weeks of age, 3 levels of 30, 60, and 90 mg Zn/kg were added to the diet by ZnO, Zn-Met, and Zn-Thr sources. Results showed that there were no significant differences between the experimental treatments in terms of egg weight, feed intake, eggshell weight, eggshell percentage, and albumen weight. In total experimental period, the supplementation of Zn-Met and Zn-Thr decreased feed conversion ratio and increased egg mass and egg production compared with ZnO 30 and 60 mg Zn/kg and control treatments (P < 0.05). The results showed that treatment effect on Zn content in egg and excreta was significant (P < 0.05). It is concluded that diets supplied with lower levels of organic Zn can maintain egg production performance, improve egg quality, enrich eggs, increase bioavailability, and reduce the negative effects of age on egg quality characteristics in laying hens compared with their oxide form.

Comparison of Zinc Sulfate and Zinc Threonine Based on Zn Bioavailability and Performance of Broiler Chicks.

The purpose of this study was to compare zinc sulfate and zinc threonine chelate based on Zn bioavailability and performance of broiler chicks. The study was conducted in a completely randomized design with 256 day-old Ross 308 chicks and eight treatments including control treatment (no zinc supplementation), three levels of zinc sulfate and zinc threonine chelate (40, 80, and 120 mg zinc per kg feed), and a common commercial chelate (Bioplex Zn®) supply 40 mg zinc per kg feed. The results of total period showed that threonine chelate group had the highest live weight compared with other treatments and lowest feed conversion ratio belonged to 80 and 120 ppm of zinc threonine chelate (p < 0.05). Zinc threonine chelate and commercial chelate treatments had the lowest cholesterol and LDL levels compared with other treatments (p < 0.05). Zinc chelate threonine which contains 80 and 120 ppm of zinc had the highest HDL and superoxide dismutase enzymes and the lowest heterophile to lymphocyte ratio compared with other treatments (p < 0.05). Relative bioavailability of zinc threonine to zinc sulfate based on body weight, feed conversion ratio, cholesterol, LDL, HDL, superoxide dismutase enzyme, ash, and zinc content in tibia were 418.75, 173.91, 131.38, 159.43, 278.63, 193.45, 156.46, and 117.65%, respectively. According to the results of broiler performance and other traits measured in this study, it seems that the use of 80 ppm of zinc threonine chelate in the broiler diet is recommended in comparison with zinc sulfate levels and other threonine chelate levels.