Dietary Calcium Research Articles

Effects of calcium pidolate on performance, carcass traits, bone biomechanical properties and mineralisation and jejunum histomorphology in broilers

ABSTRACT 1. The current study was conducted to determine the effect of dietary calcium pidolate (CalP) on performance, slaughtering characteristics, bone biomechanical properties, mineralisation and jejunum histomorphology in male broilers. A total of 200 one-day-old Ross 308 male chicks were randomly assigned to one of four treatments as five pen replicates, each containing 10 chicks. The basal diet without CalP was formulated to supply the nutritional needs of broilers and the treatment diets contained 0.30, 0.45 and 0.60 g/kg CalP, with limestone meeting the remaining calcium requirement. 2. The addition of CalP had a quadratic effect on performance (P < 0.05) and the best performance was achieved in the group that included CalP at a dose of 0.45 g/kg but 0.60 g/kg level worsened performance. Supplementing with CalP linearly decreased carcass yield (P < 0.01) and relative breast weight (P ≤ 0.05) but the relative thigh weight increased quadratically (P < 0.05) and reached a maximum at 0.45 g/kg. 3. Tibia shear force and stress linearly increased with the use of CalP in the diet (P < 0.05). Supplementation had a quadratic effect on tibial calcium (P < 0.01), reaching a maximum at 0.30 g/kg, although tibial phosphorus levels decreased linearly (P < 0.01). 4. The effect of CalP on jejunum histomorphology fluctuated and, compared to the unsupplemented control group, the villus height/crypt depth ratio increased, while the other variables decreased (P < 0.05). Decrease in crypt depth with the addition of CalP was significant (P < 0.05). 5. Using Ca-pidolate at a rate of 0.45 g/kg in broiler diets is sufficient to increase performance and tibia strength but 0.60 g/kg level negatively affected performance. In addition, the results of jejunum histomorphology were variable, but the crypt depth decreased with CalP levels and this is an important effect. However, further research is needed to detail the effect of CalP on broilers.

Effect of coated calcium feeding on growth performance, carcass traits, immunity, blood biochemistry and tibial bone morphometry in commercial broiler chicken.

The bone abnormalities pose great concern in heavy, rapidly growing broilers, resulting in significant economic loss, and health issues in birds. To address these problems and prevent unnecessary mineral excretion into environment, it is crucial to optimise the inclusion level of dietary calcium in broiler's diet. The calcium utilisation by the bird is also affected by its source, particle size, bioavailability etc. Hence this study aimed to study the effect of partially replacing conventional dietary calcium source with coated calcium on growth performance, immune response, carcass traits, blood calcium and phosphorus, and mineral retention in broilers. About 416 broiler chicks were randomly distributed into four treatments, each with eight replicates of 13 birds and fed with iso-calcium, isocaloric, and isonitrogenous diet for 42 days. The T0 (control) was a basal diet while the T1, T2, and T3, were treatment diets in which conventional calcium source (limestone) was partially replaced with coated calcium by 10, 20, and 30% respectively. The birds of T3 group showed higher (P < 0.05) body weight gain, better feed conversion ratio and higher carcass yields compared to T0, T1, and T2 diet fed birds. Further the treatment groups exhibited higher (P < 0.05) cell-mediated and humoral immune responses and immune organ weights compared to control. The tibial bone weight, length and average diameter was highest (P < 0.05) in T3. Moreover, the T3 diet fed group also showed higher (P < 0.05) calcium and phosphorus content in serum and bone and lowest content of these minerals in the excreta followed by T2, T1 and control. These findings suggest that a 30% conventional calcium source with coated calcium may be used as a high-grade mineral source for broiler chicken feed.

Dietary calcium intake among Iranian adults: Iranian Multicenter Osteoporosis Study (IMOS-2021).

Adequate dietary consumption of calcium is crucial in the preservation of bone health and the prevention of osteoporosis. This study investigated the prevalence of insufficient dietary calcium intake among individuals aged ≥50 years in Iran. We analyzed data from the Iranian Multicenter Osteoporosis Study (IMOS-2021). Participants aged 50 years and older completed a 168-item food frequency questionnaire. Insufficient dietary calcium intake was characterized as a daily calcium intake of <1000 mg for men aged 50-70 years, and <1200 mg for men over 70 years and women over 50 years and older. Stata v17 statistical software facilitated a survey set analysis to estimate the population's mean and median dietary calcium intake and the prevalence of insufficient dietary calcium intake. The study included 1450 participants with a mean age of 60.7±7.9 years. The estimated mean dietary calcium intake in Iran was 1062.7 mg/day (95% CI: 1029.6-1095.8), with a median intake of 943.5 mg/d (95% CI: 910.5-976.4). The prevalence of insufficient dietary calcium intake in Iran was estimated to be 62.9% (95% CI: 60.0%-65.7%). Notably, the prevalence was higher among women at 75.5% (95% CI: 71.9%-78.8%), compared to men at 47.8% (95% CI: 43.4%-52.3%) with a significant difference (P<0.001). In age-related findings, individuals aged 65 years and older had a higher prevalence of insufficient intake, at 69.0% (95% CI: 63.9%-74.0%), versus those under 65 years, at 60.3% (95% CI: 56.9%-63.8%), with this difference being statistically significant (P = 0.007). Furthermore, a significant inverse relationship was identified between both educational years and socioeconomic status and the prevalence of insufficient dietary calcium intake (Ps for trends<0.001). Our findings revealed a significant prevalence of insufficient dietary calcium intake in women and those aged 65 and older. We advocate for targeted public health strategies to ensure sufficient dietary calcium intake across these populations.

Exploring the Role of Dietary Calcium Intake in Muscle and Cardiovascular Performance Among Young Athletes

The importance of dietary calcium intake in bone metabolism has been well established; however, it is still less investigated in health-related components, especially addressing muscle performance. This study aims to compare dietary calcium intake and its relationship with cardiovascular and muscular performance in young athletes (lacrosse, Baseball, and soccer players). In this cross-sectional study, 95 participants (ages 18 to 30) participated during two visits to the Human Performance Laboratory. Participants completed body composition, lower and upper body muscle performance, cardiorespiratory protocol, and questionnaires related to dietary calcium intake. One-way ANOVA was used to determine the difference in the calcium intake between groups. The Pearson Correlation Coefficient was used to investigate the relationship between dietary calcium intake and muscle performance variables. Further, linear regression was used to assess the predictive value of calcium variables on overall muscle performance. Lacrosse players had significantly higher calcium intake than Baseball and soccer players (p &lt; 0.05). There was a significant positive correlation between dietary calcium intake and the number of push-ups (r = 0.28; p = 0.03). CIBW and CI explained 4.3% and nearly 25% of the change in MPI, respectively (p &lt; 0.001). This suggests the possible role of dietary calcium intake in enhancing health-related fitness components and highlights the need to explore its involvement in muscle-bone crosstalk.

Relationship between emotional eating and nutritional intake in adult women with overweight and obesity: a cross-sectional study

BackgroundEmotional eating (EE) is particularly prevalent in overweight or obese women, who may turn to food as a way to cope with stress, sadness, or anxiety. Limited research has been conducted on the association between EE and nutritional intake. Therefore, present study was designed to explore this association in adult women with overweight and obesity.MethodsIn this cross-sectional study, the relationship between EE and nutritional intake in 303 overweight and obese women (aged 18–50 years) was examined. The researchers used the validated semi-quantitative Food Frequency Questionnaire (FFQ) to assess participants’ nutritional intake and the Dutch Eating Behavior Questionnaire (DEBQ) to evaluate their eating behavior. To determine the association between EE and nutritional intake, we employed the multiple linear regression analysis.ResultsThe frequency of high intensity EE was 64.4% among the study participants and the mean total score of EE subscale of DBEQ was 2.32 ± 0.81. The total score of EE was positively associated with the energy intake (β = 0.396, P = 0.007), even after adjusting for age and BMI. In addition, a significant inverse association was found between the score of EE and the daily intake of calcium (β= -0.219, P = 0.026), riboflavin (β= -0.166, P = 0.043), and vitamin B12 (β= -0.271, P = 0.035), independent from energy and age. Also the results showed a significant positive association between the score of EE and the frequency of daily intake of cracker, muffin, cake, cream cake, pastry, candy, ice cream, pickles, melon, hydrogenated vegetable oil, peanut, salted and roasted seeds, and corn-cheese puff snack.ConclusionThis study found that overweight or obese women with higher intensity of EE might have a higher intake of energy and a lower intake of dietary calcium, riboflavin and vitamin B12. Integrating a balanced diet with psychotherapy is suggested to help individuals with EE reducing the urge to eat in response to emotions.

Effects of feed particle size, calcium concentration and phytase supplementation on InsP6 degradation in broiler chickens fed pelleted diets

ABSTRACT 1. The objective of the trial was to study the single and interactive effects of feed particle size in pelleted feed, dietary calcium (Ca) concentration and microbial phytase supplementation in broiler chickens. The studied traits were myo-inositol (1,2,3,4,5,6) hexakis (dihydrogen phosphate) (InsP6) degradation, pre-caecal digestibility of phosphorus (P), Ca and amino acids (AA) and retention of P, Ca and nitrogen (N). 2. Male Ross 308 broiler chickens were housed in metabolism units in groups of 10 and allocated to one of eight diets with seven pen replicates per diet. The 2 × 2 × 2-factorial arrangement included coarse and fine feed particle size (309 or 222 µm), low and high Ca concentration (4.9 and 7.2 g/kg) and without or with phytase supplementation (1,000 FTU/kg). 3. Pre-caecal InsP6 disappearance was higher with coarse than fine feed particle size when no phytase was added (54 vs. 48%) but not when phytase was added (74%; p = 0.046). High dietary Ca feeds decreased pre-caecal InsP6 disappearance (67 to 59%) and P digestibility (65 to 55%; p < 0.001). Gizzard pH was lower with coarse than fine feed particle size and higher with high Ca than low Ca (p < 0.001). Pre-caecal digestibility of most AA was approximately 3.5%-points lower with high Ca without phytase compared to the other treatments (p ≤ 0.047). Coarse feed particle size caused higher pre-caecal AA digestibility than fine particle size (~2%-points; p ≤ 0.031). InsP6 disappearance in the crop increased at high Ca concentration when phytase was added (22 vs. 37%; p = 0.011). 4. Coarser feed particle size in pellets increased gastrointestinal InsP6 degradation and nutrient digestibility, likely owing to effects on the gizzard functions. Additional Ca supply exerted antinutritive effects that was not compensated for by using coarser feed particles.

Integrated transcriptomics and untargeted metabolomics reveal bone development and metabolism of newly weaned mice in response to dietary calcium and boron levels.

Epidemiological and animal studies have indicated that calcium and boron are essential for bone development and metabolism. However, limited information is available regarding the effects of boron supplementation on bone development and metabolism in newly weaned infants with either calcium deficiency or calcium sufficiency. This study assessed the effects of dietary boron supplementation (0 and 3 mg kg-1) on bone development and metabolism, in a newly weaned mouse model, under both calcium deficiency and sufficiency feeding conditions. The results show that mice fed a calcium sufficient diet exhibited lower fat percentage and final body weight than those fed a calcium deficient diet. Boron supplementation reduced the serum high-density lipoprotein cholesterol level and up-regulated the mRNA levels of FABP3, PPAR-γ, and CaMK in the intestinal mucosa. Importantly, boron supplementation increased the tibial weight in mice on a calcium-sufficient diet and enhanced the tibial volume in those on a calcium-deficient diet. Metabolomic analysis highlighted calcium and boron's impact on metabolites like carboxylic acids and derivatives, fatty acyls, steroids and steroid derivatives, benzene and substituted derivatives, organonitrogen compounds, organooxygen compounds, and phenols, and were related to lipid metabolism and the neural signaling pathway. Transcriptomic analysis corroborated the role of calcium and boron in modulating bone metabolism via the JAK-STAT, calcium signaling, lipid metabolism, and inflammatory pathways. Multi-omics analysis indicated a strong correlation between calcium signaling pathways, lipid metabolism signaling, and dietary calcium and boron contents. This research provides insights into these complex mechanisms, potentially paving the way for novel interventions against calcium and boron deficiencies and bone metabolism abnormalities in clinical settings.

Effect of dietary calcium and vitamin D supplements on plasma bone turnover biomarkers, bone mineralization, bone strength, and lameness score in gilts.

This study investigated the impact of calcium (Ca) and vitamin D supplements on bone metabolism, bone measurement, lameness, and selection rate in gilts fed five dietary treatments. Two Ca levels (6.85/6.42 [adequate; ACa] or 8.99/8.56 [high; HCa] g/kg) were combined with either 856 IU/kg vitamin D3 (Danish feeding standards; adequate; AD3) or 50 μg/kg 25-hydroxyvitamin D3 (high; HHyD) to create ACaAD3, HCaAD3, ACaHHyD, and HCaHHyD diets. The values 6.85/6.42 and 8.99/8.56g/kg correspond to adequate and high Ca supply for gilts weighing 32 to 100 and 100 to 180kg body weight (BW), respectively. The fifth diet was a combination of HCa and 2,000 IU/kg vitamin D3 (high; HD3) to create HCaHD3. Two hundred gilts were phase fed the dietary treatments from 32 to 100 and 100 to 180kg BW until they were slaughtered, either at 100 or 180kg BW. The gilts were weighed fortnightly, and plasma and urine samples were collected at 100 and 180kg BW. At slaughter, the 2nd and 3rd metacarpal bones were collected for bone parameters measurements. Lameness and selection rate were assessed within the last 7 d at 100 and 180kg BW. Dietary treatments did not affect gilts' growth performance and plasma concentration of Ca, but urinary concentration of Ca was greater in HCa-supplemented gilts at both 100 (P = 0.003) and 180 (P = 0.05) kg BW. Plasma concentration of vitamin D3 (P < 0.001) and 25-hydroxyvitamin D3 (P < 0.001) showed dose-dependent responses at both 100 and 180kg BW. Bone-specific alkaline phosphatase was greater (P = 0.02) in the plasma sample collected at 180kg BW in gilts fed the HCaHD3 diet and tended to be greater in gilts fed the ACaAD3 diet (P = 0.06). The bone ash content (P = 0.02) was greater in gilts fed the HCaAD3 diet and slaughtered at 100kg BW compared with gilts fed the ACaAD3 and ACaHHyD diets. However, bone weight, length, thickness, dry matter, and mineral content did not differ among the dietary treatments at both 100 and 180kg BW (P > 0.05). Neither lameness nor selection rate was affected by the dietary treatments. The average daily gain of gilts weighing 32 to 100 and 100 to 180kg BW showed a positive correlation with bone strength (r = 0.37; P < 0.001) and bone ash content (r = 0.24; P = 0.02), respectively. In conclusion, higher Ca and vitamin D3 supplementation slightly increased bone ash content but had no effect on lameness or selection rate of the gilts compared to those fed according to the Danish nutrient standards.

Dietary calcium intake in relation to metabolic syndrome in adults: A systematic review and dose-response meta-analysis of epidemiological studies with GRADE assessment.

Numerous studies have examined the relationship of calcium intake and metabolic syndrome (MetS) in adults in previous decades; but the results were inconsistent across different societies. This systematic review and dose-response meta-analysis assessed the relation between calcium consumption and MetS in adults. We did a systematic search of all articles published up to July 2023 in Scopus, PubMed/Medline, ISI Web of Science electronic databases, and Google Scholar. Observational studies investigated the association between dietary calcium (Ca) intake and MetS in adults were eligible to be included. For computing the estimates, a random effects model was applied. Combining 24 effect size from 17 investigations (15 cross-sectional and two cohort studies) with 74,720 participants and 18,200 cases showed that highest versus lowest level of dietary Ca intake was related to 23% significant decreased odds of MetS (OR = 0.77; 95% CI: 0.66, 0.89). Linear dose-response analysis of estimates from 12 investigations showed that each 100 mg/day increment in dietary Ca intake was associated with 3% marginally significant decreased odds in MetS (OR = 0.97; 95%CI: 0.93, 1.01). In nonlinear dose-response analysis of 12 studies with 67,896 participants, a significant association between dietary calcium intake and MetS was found (Pnonlinearity <0.001); such that 500 mg/day dietary calcium intake was related to maximum decrease in odds of MetS. According to this meta-analysis, the likelihood of MetS was significantly lower in adults with higher level of dietary calcium intake. Further large-scale prospective cohort investigations are needed to obtain stronger and more accurate results.

6487 Hypercalcemia In Pregnancy Due To An Ectopic Parathyroid Adenoma: A Diagnostic Dilemma

Abstract Disclosure: S.S. Patel: None. M.B. Sharma: None. Introduction: Hypercalcemia is a rare complication of pregnancy, with the most common cause being primary hyperparathyroidism due to a parathyroid adenoma. Ultrasound is the primary modality used for localization, as sestamibi and computed tomography (CT) carry the risk of potential harm to the fetus. We present the case of hypercalcemia in a pregnant female that failed to resolve after two gland parathyroidectomy, necessitating a sestamibi parathyroid scan to localize an ectopic parathyroid adenoma. Case: A 40-year-old pregnant woman at 12 weeks of gestation presented with hypercalcemia, with a corrected calcium level of 12.5 mg/dL (8.7-10.4 mg/dL). She complained of nausea and vomiting but denied any personal or family history of hypercalcemia. Further evaluation revealed primary hyperparathyroidism as the etiology, with Intact PTH of 429.2 pg/mL (18.5-88.0 pg/mL), ionized calcium of 1.45 mmol/L (1.12-1.32 mmol/L), 25-OH vitamin D of 16.4 ng/mL (30-100 ng/mL), phosphorus of 1.3 mg/dL (2.4-5.1 mg/dL), and creatinine of 0.71 mg/dL (0.5-0.8 mg/dL). Notably, her calcium level had been 19.2 mg/dL two weeks earlier during an episode of hyperemesis gravidarum. Hypercalcemia proved relatively resistant to treatment with intravenous hydration and subcutaneous calcitonin. Ultrasound of the neck failed to reveal a parathyroid adenoma. The patient then underwent surgical neck exploration, during which two parathyroid glands were removed, resulting in an intraoperative PTH drop from 440 to 340 pg/mL. Postoperative calcium levels remained elevated at 12.9 mg/dL, prompting the resumption of treatment. Oral sodium and potassium phosphate was added to bind dietary calcium. After an extensive multidisciplinary discussion, a 99mTc-sestamibi parathyroid scan with a lower dose of sestamibi and without CT was recommended. This revealed an ectopic parathyroid adenoma in the anterior mediastinum. Surgical removal of the ectopic parathyroid adenoma in the second trimester finally led to a significant intraoperative PTH drop from 315 to 28 pg/mL. The postoperative course was complicated by hypocalcemia and hypomagnesemia, requiring calcium, vitamin D, and magnesium supplements. These complications resolved over the following days. The patient remained normocalcemic for the remaining pregnancy and delivered a healthy male infant at 34 weeks. Conclusion: Hypercalcemia in pregnancy is associated with fetal and maternal complications, warranting adequate management and close follow-up. The use of 99mTc-sestamibi parathyroid scan is typically not recommended in pregnancy due to concern for fetal harm; however, there are a few studies showing no association with increased birth defects or adverse pregnancy outcomes at low radiotracer doses. Hence, a sestamibi parathyroid scan can be considered during pregnancy to localize an adenoma after a careful review of the benefits versus risks. Presentation: 6/2/2024

Comparative Study on Calcium-enriched Finger Millet Tisane: Optimizing Soaking and Roasting Methods

This study focuses on the development of a calcium-rich herbal tisane using finger millet, a grain known for its high calcium content, aimed at enhancing dietary calcium intake. Two distinct processing methods were employed to optimize the calcium content of the tisane. In Treatment 1, Finger millet was roasted and combined with spice powder, while in Treatment 2, Finger millet underwent soaking, cabinet drying, roasting, and then blending with spice powder. The calcium content and overall quality of both treatments were evaluated, revealing a marginal increase in calcium concentration in Treatment 2, attributed to the additional processing steps. Specifically, Treatment 2 yielded a maximum calcium content of 396 mg compared to 380 mg in Treatment 1, demonstrating the effectiveness of the additional soaking and drying steps in enhancing calcium bioavailability. The final product was further enriched with a blend of spices, including dry ginger, cinnamon, cardamom, Arjuna bark, fennel seeds, and Tulsi leaves, contributing to its healthful properties. Organoleptic evaluations, conducted to assess sensory attributes such as flavor, aroma, and overall acceptability, indicated that both treatments were well-received by consumers. This suggests the product's potential for consumer acceptance and market viability. The findings suggest that calcium-enriched Finger millet tisane could serve as a valuable functional beverage, particularly for populations at risk of calcium deficiency. Its nutrient profile, combined with favorable sensory attributes, positions it as a promising option for improving dietary calcium intake and promoting overall health. Further research on larger sample sizes and bioavailability studies could reinforce its potential as a functional health beverage.

Calcium carbonate supplementation for the prevention of preeclampsia in high-risk pregnant women: a randomized clinical trial protocol

BackgroundPreeclampsia (PE) is a significant cause of maternal mortality worldwide, affecting 2% to 8% of pregnancies. The World Health Organization recommends the use of low-dose acetylsalicylic acid (100 mg of aspirin) and 1.5 to 2 g of calcium carbonate during pregnancy to prevent PE. However, robust evidence supporting the efficacy of calcium supplementation is still needed. This study aims to assess the efficacy of calcium carbonate in preventing preeclampsia in high-risk pregnant women.MethodsA triple-blind, randomized clinical trial will be conducted at an outpatient clinic in Brazil between May 2024 and March 2026. Pregnant women at high risk of developing preeclampsia and with low dietary calcium intake will be randomly assigned to one of three groups: one group will receive calcium carbonate capsules (commercially available in Brazil) along with 100 mg of aspirin; the second group will receive calcium carbonate derived from Crassostrea sp. along with 100 mg of aspirin; and the control group will receive a placebo alongside 100 mg of aspirin. The primary outcome is the diagnosis of preeclampsia during pregnancy, while secondary outcomes evaluate maternal and fetal health indicators.DiscussionThis trial seeks to generate evidence on the efficacy of calcium carbonate in preeclampsia prevention, with a focus on comparing industrial calcium carbonate with calcium carbonate sourced from Crassostrea sp., a more sustainable alternative.Trial registrationThe study was approved by the Research Ethics Committee of the Federal University of Sergipe and registered in the Brazilian Registry of Clinical Trials (ReBEC), under the ID RBR-7hqhj3y. Registered on November 16, 2023.

Familial hypocalciuric hypercalcemia in an infant: diagnosis and management quandaries.

Familial hypocalciuric hypercalcemia (FHH) is typically a benign condition characterized by elevated serum calcium, low urinary calcium excretion, and non-suppressed circulating levels of parathyroid hormone (PTH), usually requiring no intervention. FHH is inherited in an autosomal-dominant manner. Three subtypes are described, representing variants in genes with critical roles in extracellular calcium-sensing. FHH1, due to heterozygous inactivating variants in the calcium-sensing receptor gene (CASR), accounts for the majority of cases. FHH2, due to variants in GNA11, encoding the α-subunit of the downstream signaling protein, G11, is the rarest form of FHH. FHH3, resulting from variants in AP2S1, may present with a more pronounced phenotype than FHH1 or FHH2. We describe herein a newborn girl presenting with in utero femoral fractures, hypercalcemia, hypophosphatemia, and elevated circulating PTH. She was diagnosed with mild hyperparathyroidism and provided supplemental phosphate upon hospital discharge. However, serum calcium and PTH remained elevated at 5mo of age. The combination of low-calcium formula and cinacalcet improved the biochemical profile. No pathogenic variants in the coding region of CASR were identified; subsequent whole exome sequencing revealed a G- > T transition at c.44 (p.R15L) in AP2S1. Family studies identified this variant in the father and an affected brother. The mother was unexpectedly found to be hypocalcemic and was diagnosed with idiopathic hypoparathyroidism. This case demonstrates successful treatment of FHH3 using a low-calcium formula to limit dietary calcium availability and cinacalcet to modify PTH levels.

Effects of dietary calcium and microbial phytase on the bioavailability of two sources of zinc in broilers

ABSTRACT 1. The objective of this study was to test the effect of microbial phytase and calcium (Ca) levels on the Zn bioavailability depending on the Zn source. 2. A total of 144, one-day-old broilers received a diet containing 40 mg Zn/kg for 1 week. They were then assigned to one of the eight experimental treatments during 2 weeks. Diets contained 27 mg native Zn and were formulated according to a 2 × 2 × 2 factorial design with two added Zn sources (23 mg Zn/kg), sulphate (ZnSO4) or oxide (ZnO); two dietary Ca levels of either 6 (low) or 10 g/kg (moderate); and two microbial phytase levels, of either 0 or 750 phytase unit/kg. 3. Moderate Ca plus phytase improved body weight gain (BWG) and low Ca level without microbial phytase decreased tibia weight (Ca × Phy; p = 0.049). Zinc oxide resulted in a higher tibia development (i.e. tibia weight and length; p < 0.05) and BWG (p = 0.009) and lower FCR (p < 0.001) compared to ZnSO4. 4. Phytase improved tibia Zn concentration especially in birds given ZnSO4 compared to ZnO (Zn × Phy; p = 0.049). Moderate Ca diets improved tibial characteristics and Zn deposition compared to low Ca diets (p < 0.05). 5. Soluble Zn in the gizzard increased in the presence of phytase (p = 0.011), while higher dietary Ca reduced this in birds receiving ZnO (p = 0.004). In the jejunum, Zn solubility was higher with phytase (p = 0.008). 6. Under the conditions of this study, dietary levels of Ca and microbial phytase affect Zn availability in broilers more than the Zn source.

Experiences, acceptability and barriers to calcium supplementation during pregnancy in Dar es Salaam, Tanzania.

Calcium supplementation in pregnancy is recommended in contexts with low dietary calcium intake to reduce the risk of pre-eclampsia and its complications. The World Health Organisation suggested high-dose calcium supplementation (1500-2000 mg/day), divided into three doses and taken at different times from daily iron-folic supplements. We conducted a mixed methods evaluation study to assess experiences, acceptability and barriers to high-dose calcium supplementation from the perspectives of pregnant women and antenatal health care providers at two public health facilities in Dar es Salaam, Tanzania. Descriptive statistics and thematic analysis were used to characterise acceptability, barriers and overall experiences of using high-dose calcium supplementation. Pregnant women in the cohort were aged 19-41 years, with 32.4% being primiparous. The proportion of pregnant women who liked calcium supplements 'a lot' decreased from 50.2% at the first visit to 31.8% at the last antenatal follow-up visit. Adherence was 71.3% (interquartile range: 50.5%, 89.3%), with only 24.0% of the participants taking 90% or more of the required supplements. Although participants expressed positive attitudes towards using calcium supplements, they also voiced concerns about the large size, side effects, the potential to forget and the burden of taking calcium supplements three times per day. Antenatal health care providers also affirmed the high burden of taking calcium supplements in addition to iron-folic acid supplements. Participants expressed the acceptability of using calcium supplements during pregnancy, but adherence to three doses per day posed challenges to pregnant women. Reducing the number of calcium supplement doses per day may improve adherence.

Food-based dietary guidelines for optimizing calcium intakes for reproductive-aged women in Ethiopia using local foods.

Increasing dietary calcium intakes of Ethiopian women of reproductive age (WRA) is a public health priority for reducing pre-eclampsia in pregnancy. Using linear programming, we determined whether locally available foods consumed by WRA in nine regions (urban and rural) and two administrative cities of Ethiopia could provide 1000mg/day of dietary calcium, and we identified food-based recommendations (FBRs) to improve dietary calcium adequacy in each region. Results showed that diets providing 1000mg/day of calcium were feasible in eight regions (40%) of the target populations examined. It would, however, require marked changes for most populations (90%), increasing the number of servings per week of several food groups to levels close to those of high consumers in each population. The selected calcium-specific FBRs integrate well into the 2022 Ethiopian Dietary Guidelines, requiring additional messages to consume green leafy vegetables, milk, root crops, or teff (Eragrostis tef) or to consume a higher number of servings of vegetables than currently recommended, depending on the population. In conclusion, these analyses show that a food-based approach can be used to achieve dietary calcium adequacy among WRA in 40% of the populations examined. For the other populations, food-based interventions alone may be inadequate and other interventions are likely needed.

Dietary mineral intake and risk of bladder cancer: a systematic review and meta-analysis.

This meta-analysis aimed to investigate the association between dietary mineral intake and the risk of bladder cancer. Relevant studies on bladder cancer and dietary mineral intake, including sodium, calcium, iron, magnesium, phosphorus, potassium, and zinc, were systematically identified through searches in Scopus and PubMed up to July 2024. Data from 12 studies were pooled using odds ratios (OR) and 95% confidence intervals (CI) with a random-effects model. The meta-analysis of 12 studies indicated a positive association between higher dietary sodium intake and bladder cancer risk (OR = 1.62, 95% CI: 1.04-2.55), with significant heterogeneity observed. No clear linear or nonlinear dose-response relationship was found for sodium intake. However, no significant associations were found between the intake of other minerals and the risk of bladder cancer. This study suggests that a high intake of sodium is significantly associated with an increased risk of bladder cancer. Further research is needed to explore the potential mechanisms underlying this relationship.

The effect of exogenous and genetic factors on a decrease in bone mineral density in children with cystic fibrosis

Osteoporosis is acomplication of cystic fibrosis, the relevance of studying which is associated with an increase in the life expectancy of patients and an increase in the proportion of adults in the general patient population. The aim of the research is to study exogenous and genetic factors of bone mineral density reduction in patients with cystic fibrosis and healthy children. Methods. 100 children with cystic fibrosis and 61 healthy children over 6 years old were examined. All children underwent X-ray densitometry with the DEXXUM device (South Korea). Vitamin D intake, dietary calcium intake and physical activity were assessed using aquestionnaire. Vitamin D levels were assessed by enzyme immunoassay based on the blood content of its intermediate metabolite 25(OH)D. The determination of biochemical parameters was carried out in the CMD laboratory using the enzyme immunoassay method. Polymorphisms of the VDR, COL1A1, and CALCR genes were analyzed by restriction analysis (PDRF). Results. It was found that patients with CF (38%) are more likely to have low BMD compared with healthy children (18%). Low indicators of nutritional status had anegative impact on the BMD. The processes of osteoresorption prevail over the processes of osteogenesis in CF. The features of the course of the disease neutralize the influence of genetic factors that have been identified in healthy children. The effect of dietary calcium intake was significant for healthy children and had no effect on BMD in patients with CF, since patients adhere to acalcium-enriched diet. The effect of the CALCR and COL1A1 genes and dietary calcium intake on the BMD of healthy children has been established. Conclusion. In cystic fibrosis, the leading risk factors for decreased bone mineral density are: ahistory of meconium ileus, chronic infection with Pseudomonas aeruginosa, low nutritional status, and decreased pulmonary function (FEV1,% predicted). For healthy children, the influence of the CALCR and COL1A1 genes and dietary calcium intake are significant.

358 The effect of increasing dietary limestone concentration on growth performance, gas flux, and carcass characteristics in finishing beef cattle

Abstract Reducing methane (CH4) emissions from beef cattle is desirable as CH4 is a greenhouse gas that represents an energetic loss from the production system. Limestone is commonly fed to cattle as a source of calcium but may also act as a rumen buffer and decrease CH4 emissions by limiting hydrogen availability for methanogenesis. The objective of this experiment was to determine if diet limestone concentration influences growth performance, gas flux, and carcass characteristics in finishing beef cattle. Yearling steers [n = 16; initial body weight (BW) 619 ± 34 kg] were stratified by BW and randomly assigned to 1 of 2 isocaloric and isonitrogenous dietary treatments in a completely randomized design where limestone was included at 1.3% (1X) or 2.6% (2X) of diet dry matter (DM). Finishing diets were formulated to contain 0.43 or 0.96% DM as Ca and were fed ad libitum using automated cattle feeders (SmartFeed Pro; C-Lock Inc.; Rapid City, SD) in a single pen for the final 37 d of finishing. Body weights were measured on d -1, 0, 36, and 37. An automated head chamber system (GreenFeed; C-Lock Inc.) was used to measure gas flux. Analysis of variance was conducted using JMP Pro 17 to determine the fixed effect of treatment with individual animal as the experimental unit. Statistical significance was defined as P ≤ 0.05 with a tendency defined as 0.05 &amp;lt; P ≤ 0.10. Increasing the dietary limestone concentration from 1.3 to 2.6% of DM did not influence DM intake, but numerically increased final shrunk BW (P = 0.68) and hot carcass weight (P = 0.75) and increased average daily gain (ADG; P = 0.02) and gain to feed ratio (G:F) by approximately 12%. Cattle fed the 2X diet tended to have 6.5% greater ribeye area (P = 0.09), but similar USDA yield grade, backfat thickness, and dressing percentage (P ≥ 0.34) when compared with cattle fed the 1X diet. Daily CO2 and CH4 emissions, daily O2 consumption, CH4 yield, and respiratory quotient were unaffected by treatment (P ≥ 0.47). The improvement in ADG resulted in a tendency for CH4 emission intensity to be decreased by 9.1% (P = 0.09) when the concentration of limestone was 2.6% of dietary DM. While increasing dietary limestone concentration from 1.3 to 2.6% of diet DM did not influence absolute daily CH4 emissions, it increased ADG through an improvement in feed efficiency, which translated to a tendency for a reduction in CH4 emission intensity. These preliminary data suggest that there may be a benefit to feeding limestone or calcium at levels greater than currently recommended by the NASEM (2016). Future research should focus on determining optimum dietary limestone or calcium levels for finishing cattle.

359 Optimization of calcium inclusion levels in diets fed to growing and finishing beef cattle

Abstract Calcium (Ca) is a mineral that has an essential role in many biochemical pathways and functions of beef cattle. Limestone is the primary supplemental source of Ca in diets fed to growing and finishing cattle in the United States. Preliminary data indicated that inclusion of dietary Ca above the NASEM (2016) requirements as well as mean and modal concentrations reported by the most recent survey of consulting nutritionists may improve average daily gain (ADG) and feed efficiency (gain to feed ration; G:F) of finishing beef cattle. Thus, the objective of this experiment was to determine the optimal concentration of Ca in growing and finishing diets when limestone was the supplemental source of added Ca. A database was constructed containing 89 treatment means from 23 experiments published from 1963 to 2024 where dietary Ca inclusion via limestone represented treatments. Search parameters to construct the database included a combination of Ca, limestone, performance, efficiency, ADG, G:F, feedlot cattle, finishing cattle, growing cattle, and backgrounding cattle. Data were analyzed in JMP Pro 17 using a mixed model to determine linear and quadratic relationships between dietary Ca and ADG, DMI, or G:F with citation as a random effect. An economic sensitivity analysis was conducted to determine variables most influential to the dietary Ca concentration projected to minimize cost of gain using the above models. Concentration of dietary calcium was selected as the explanatory variable for the models rather than limestone because a greater proportion of variation was accounted for in the response variables prior to the citation adjustment (Ca R2 0.05 to 0.25; limestone R2 0.06 to 0.21). Diet Ca concentration and DMI were unrelated (P ≥ 0.75), but diet Ca was related to both ADG (R2 = 0.84; RMSE = 0.36; P ≤ 0.03) and G:F (R2 = 0.74; RMSE = 0.01; P &amp;lt; 0.01) in a quadratic fashion. Maximum ADG occurred when Ca was included at 1.20% of diet DM; approximately 2.6-fold greater than Ca requirements estimated by NASEM (2016). Cost of gain was minimized when Ca was 1.35% of diet DM. Sensitivity analysis revealed Ca concentration to minimize cost of gain was sensitive to changes in DMI, ADG, days on feed, ration cost and cost of yardage. These results provide further evidence that it may be beneficial to feed a greater amount of Ca than currently recommended by the NASEM (2016) for growing and finishing cattle. Future pen-scale feeding trials are warranted to validate the results of this meta-analysis and to determine the dose response of cattle fed graded levels of Ca. Future research should also be conducted to determine the mechanism of action responsible for the observed improvements in animal performance and efficiency resulting from feeding an increased amount of dietary Ca.