Effect Of Calcium Levels Research Articles

48. Effects of calcium levels and increasing doses of phytase on phosphorus and calcium digestibilities, zootechnical performances and mineralization in weaned piglets

48. Effects of calcium levels and increasing doses of phytase on phosphorus and calcium digestibilities, zootechnical performances and mineralization in weaned piglets

Effect of calcium levels on structure and function of mitochondria in yeast under high glucose fermentation.

In this study, the effects of calcium levels on structure and function of mitochondria under high glucose environment were studied. In the high glucose environment, yeast growth capacity was inhibited, and intracellular reactive oxygen species (ROS) content was increased from 6 h to 12 h, while ROS content was reduced in group with 1 × 10-1 and 1 g/L CaCl2 level from 24 h to 36 h. Exogenous calcium addition had a significant effect on the elevation of intracellular Ca2+ and cytochrome C content in yeast from 6 h to 12 h; mitochondrial membrane potential decreased with the increase of CaCl2 level under high glucose levels. Mitochondrial swelling of yeast was influenced by high glucose levels and showed a regulatory dynamic change by Ca2+ levels. Isocitrate dehydrogenase activity increased in 1 × 10-3 g/L CaCl2 level from 6 h to 12 h, α-ketoglutarate dehydrogenase activity increased with an increase in CaCl2 level from 6 h to 24 h. Calcium affected the structure and function of mitochondria by regulating the intracellular signal, enzymes in tricarboxylic acid cycle, and cytochrome system of yeast under high glucose stress.

Effect of Calcium Level in Feed on Blood Profile of Broiler Chicken

This study aims to determine the effect of calcium supplementation in feed on the blood profile of broilers chickens. This research was conducted in a broiler chicken coop, owned by breeders in Sasi Village, Kefamenanu City District, North Central East District. This research was conducted from July to August 2020. This study used 96 broilers. The method used in this was a completely randomized design consisting of 4 replications and 4 treatments. The treatments given were T0 (control diet), T1 (calcium supplementation 1,00 %), T2 (calcium supplementation 1,50 %), T3 (calcium supplementation 2,00 %). The variables observed in this study were the content of erythrocytes, hemoglobin, and blood leucocytes. The data obtained were analyzed using analysis of variance. Analysis of variance showed that the treatment had no significant effect on erythrocytes, hemoglobin, and leucocytes of broiler chickens. It was concluded that the addition of calcium in feed at different levels did not increase the content of erythrocytes, hemoglobin, and leucocytes of broiler chickens aged 6 weeks.

Effects of calcium level and source, formic acid, and phytase on phytate degradation and the microbiota in the digestive tract of broiler chickens

BackgroundDiet acidification, dietary calcium (Ca) level, and phytase supplementation are known influences on the microbial community in the digestive tract and on phosphorus (P) utilization of broiler chickens. Effects of dietary factors and microbiota on P utilization may be linked because microorganisms produce enzymes that release P from phytate (InsP6), the main source of P in plant feedstuffs. This study aimed to detect linkages between microbiota and InsP6 degradation by acidifying diets (i.e., replacing Ca carbonate (CaCO3) by Ca formate or adding formic acid to CaCO3-containing diets), varying Ca levels, and supplementing phytase in a three-factorial design. We investigated i) the microbial community and pH in the digestive tract, ii) prececal (pc) P and Ca digestibility, and iii) InsP6 degradation.ResultsAll factors under investigation influenced digesta pH and the microbiota composition. Predicted functionality and relative abundance of microorganisms indicated that diets influenced the potential contribution of the microbiota on InsP degradation. Values of InsP6 degradation and relative abundance of the strains Lactobacillus johnsonii and Lactobacillus reuteri were correlated. Phytase supplementation increased pc InsP6 disappearance, with differences between Ca levels, and influenced concentrations of lower inositol phosphate isomers in the digestive tract. Formic acid supplementation increased pc InsP6 degradation to myo-inositol. Replacing CaCO3 by Ca-formate and the high level of these Ca sources reduced pc InsP6 disappearance, except when the combination of CaCO3 + formic acid was used. Supplementing phytase to CaCO3 + formic acid led to the highest InsP6 disappearance (52%) in the crop and increased myo-inositol concentration in the ileum digesta. Supplementing phytase leveled the effect of high Ca content on pc InsP6 disappearance.ConclusionsThe results point towards a contribution of changing microbial community on InsP6 degradation in the crop and up to the terminal ileum. This is indicated by relationships between InsP6 degradation and relative abundance of phosphatase-producing strains. Functional predictions supported influences of microbiota on InsP6 degradation. The extent of such effects remains to be clarified. InsP6 degradation may also be influenced by variation of pH caused by dietary concentration and solubility of the Ca in the feed.

Effects of Calcium Levels in Artificial Pellet Feed on the Growth and Survival Rate of Black Apple Snails (Pila polita)

The present study was conducted to evaluate the effects of different dietary calcium levels on the growth and survival rate of black apple snails (Pila polita) in the grow-out period. There were 3 replicates for each treatment and the snails were fed with five calcium levels (% dry matter) in diet as follows: 1% (Ca1), 3% (Ca3), 5% (Ca5), 7% (Ca7), and 9% (Ca9). Two-month-old juveniles with an average initial body weight of 2.13g, shell height of 21.71mm, and shell width of 16.35mm were reared in tarpaulin tanks (1 × 1 × 1m; 40cm water depth) at the density of 100 individuals per tank. After 4 months of the rearing period, the average body weight, shell height, and shell width of the snails reached the highest values in the Ca5 treatment (28.43 g, 54.97 mm, and 40.09mm, respectively) and these values were significantly different compared to the remaining calcium contents (Ca1, Ca3, Ca7, and Ca9). The survival rate of the snails in Ca3 (75.7%) was higher than in Ca1 and Ca7 (74.7%), Ca5 (73.7%), and Ca9 (71.7%). However, the survival rate was not significantly different among the treatments. Snails in Ca5 obtained the highest productivity (2.88 kg m-2) and this value was significantly different from Ca1 (2.55 kg m-2) and Ca9 (2.35 kg m-2). The results of this study showed that the growth rate and productivity of black apple snails were highest when they consumed a diet containing 5% calcium. The optimum requirement of calcium for the black apple snails in the grow-out period was 4.51%.

Additive layer manufacturing of semi-hard model cheese: Effect of calcium levels on thermo-rheological properties and shear behavior

Additive layer manufacturing (ALM) is an emerging technology for production of complex three-dimensional objects in the food sector. In this study, semi-hard model cheeses with different calcium levels (15.8 ± 0.9 to 31 ± 2 mg Ca g−1 protein) were produced to investigate thermo-rheological properties and shear behavior at large strain to set up process parameters for hot-melt extrusion based ALM. The gel-sol transition temperature (51.7 ± 0.2 to 60 ± 2 °C) significantly (P < 0.001) decreased with declining calcium levels. Hence, extrusion die temperature was set to 60 °C in capillary rheometer experiments to mimic hot-melt extrusion based ALM. The extrudate strands were evaluated visually and recorded pressure profiles were analyzed to determine critical shear rates. It was demonstrated that critical shear rate (10–30 s−1) increased significantly (P < 0.001) with decreasing calcium levels and with increasing flowability (tan δ60°C). By exceeding the critical shear rate, extrusion instabilities occurred indicating limitation of ALM processes.

Effect of calcium level and phytase addition on ileal phytate degradation and amino acid digestibility of broilers fed corn-based diets

This study investigated the effect of dietary Ca to available P (AvP) ratio and phytase supplementation on bone ash, ileal phytate degradation, and nutrient digestibility in broilers fed corn-based diets. The experimental design was a 4 × 2 factorial arrangement of treatments evaluating 4 Ca:AvP ratios (1.43, 2.14, 2.86, and 3.57) and 2 levels of phytase (0 and 1,000 phytase units/kg of feed). The 4 Ca:AvP ratios were achieved by formulating all diets to a constant AvP level of 0.28% and varying Ca levels (0.4, 0.6, 0.8, and 1.0%). Each treatment was fed to 6 cages of 8 male Ross 308 broilers from 5 to 21 d. At 21 d, digesta from the terminal ileum was collected and analyzed for energy, phytate, P, Ca, and amino acids (AA) to determine digestibility. Digesta pH was measured in each segment (crop, gizzard, duodenum, and ileum) of the digestive tract. Data were analyzed by 2-way analysis of covariance. There was a significant interaction between dietary Ca:AvP ratio and phytase supplementation for weight gain (WG), feed intake (FI), and feed conversion ratio (FCR). In diets with no phytase, Ca:AvP ratio had a greater effect on WG, FI, and FCR compared with those fed diets without phytase. The orthogonal polynomial contrasts showed that the increase in dietary Ca:AvP ratio significantly decreased WG and FI in a quadratic manner, whereas FCR increased (P < 0.05) linearly with higher dietary Ca:AvP ratio. Increasing dietary Ca:AvP ratio led to a significant quadratic decrease in phytate degradation and significant linear decreases in P digestibility and bone ash. Phytase addition increased (P < 0.05) phytate degradation and improved (P < 0.05) energy, AA, and P digestibility at all levels of Ca:AvP with no interaction (P > 0.05) between the main factors. Digestibility of AA was positively correlated (P < 0.05) with the degree of phytate degradation. Increasing dietary Ca:AvP ratio significantly increased gizzard pH in a linear manner. In conclusion, phytase (1,000 phytase units/kg of feed) improved phytate, and P and AA digestibility at all Ca:AvP ratios evaluated in this study.

Effects of phytase B on laying performance, eggshell quality and on phosphorus and calcium balance in laying hens fed phosphorus-deficient maize-soybean meal diets

A study was conducted to evaluate the effects of dietary supplementation of phytase B (product of the Aspergillus niger phyB gene expressed in Trichoderma reesei) on feed intake, laying performance, eggshell quality, and on phosphorus and calcium balance in laying hens. Seventy-two, 40 weeks old Hy Line Brown hens were fed for 14 weeks the following four phosphorus-deficient (0.12% nonphytate phosphorus, NPP), maize-soybean meal-based diets: (1) calcium-deficient (2.8% Ca) control diet; (2) diet 1 + phytase B at the activity of 2.5&amp;nbsp;acid phosphatase units (AcPU/kg); (3) control diet (3.8% Ca); (4) diet 3 + phytase B at the activity of 2.5 AcPU/ kg. Each dietary treatment was fed to 18 cages of hens, 1 hen/cage kept in individual cages. Hens fed the NPP- and Ca-deficient diets consumed more feed (P &amp;lt; 0.01) and excreted less calcium (P &amp;lt; 0.01) than those receiving P-deficient diets with the standard calcium level. There were no effects of calcium level on feed utilization, egg mass, egg weight, and eggshell breaking strength. Egg production, although numerically higher in hens fed low Ca diets with no enzyme added, failed to be significantly different due to the low number of hens investigated and therefore the measurement should be considered as preliminary and supplementary. Phytase B increased mean egg weight by about 7% in layers fed the NPP- and Ca-deficient diet (Ca &amp;times; phytase B interaction, P &amp;lt; 0.05), increased shell breaking strength, particularly at the standard calcium level, significantly enhanced amounts of calcium retained by layers and amounts of&amp;nbsp; phosphorus retained by hens fed the Ca-deficient diets. Additionally, phytase B improved Ca retention at both dietary Ca levels and phosphorus retention in hens fed the Ca-deficient diets. Results of the study indicate that the efficacy of phytase B in NPP-deficient diets is strongly influenced by the dietary calcium level and the enzyme may modulate egg weight, eggshell quality, phosphorus and calcium retention in laying hens fed low-NPP, maize-soybean meal-based diets.

Níveis de cálcio e granulometria do calcário sobre o desempenho e a qualidade da casca de ovos de poedeiras comerciais

Effects of calcium levels and limestone on laying hen performance and egg shell quality. An experiment was carried out to evaluate the influence of calcium levels and combinations of limestone particle sizes on the laying performance and egg shell quality of hens. Three hundred and sixty Hy-Line laying hens of 57 weeks of age were used, distributed in a randomized design in 3x5 factorial arrangement (3.75, 4,15 and 4,55% of calcium in the diet and 0, 25, 50, 75 and 100% of replacement of limestone powder) with 4 replicates, each consisting of 6 hens. Egg production, feed conversion, egg weight, and strength and thickness off egg shell were influenced by diet calcium levels. No single effect of limestone particle size replacement was found in the studied parameters. The average egg weight was improved when different diet calcium levels, interacting with different combinations of limestone particle sizes, were used.

Teores de cálcio em dietas para codornas japonesas no terço final de postura (45 a 57 semanas de idade)

Verificou-se o efeito dos teores de cálcio (Ca) na dieta sobre o desempenho e a qualidade dos ovos de codornas japonesas durante o terço final do ciclo de produção. Foram utilizadas 350 codornas, com 313 dias de idade, distribuídas em 35 unidades experimentais de 10 aves. O delineamento foi inteiramente ao acaso, composto de cinco níveis de Ca - 2,2; 2,6; 3,0; 3,4; 3,8% -, com sete repetições. O aumento do Ca na dieta melhorou linearmente a conversão por massa e por dúzia de ovos, melhorou a espessura de casca e influenciou o peso da gema e da casca dos ovos, além da porcentagem da casca. Observou-se redução nos teores de P, Ca e Mg na casca com o aumento dos níveis de Ca da dieta. Para os demais parâmetros, não houve efeito do teor de Ca da dieta. Considerando-se a importância da conversão alimentar, em termos econômicos e de desempenho, o teor de 3,8% de Ca na dieta mostrou-se satisfatório em atender às demais variáveis relacionadas com a qualidade dos ovos. Dieta que contenha 3,8% de Ca, correspondendo ao consumo diário de 982mg por ave, melhora a conversão alimentar e a qualidade da casca dos ovos de codornas japonesas no terço final do ciclo de produção (45 a 57 semanas de idade).

Effects of calcium levels and limestone particle size on the egg quality of semi-heavy layers in their second production cycle

A 112-day trial was carried out to evaluate the effect of dietary calcium level and limestone particle size on the egg quality of 288 Hy-Line Brown semi-heavy layers, with 83 weeks of age at the beginning of the experiment. A completely randomized experimental design was applied in a 2x3 factorial arrangement, with two dietary calcium levels (3.5 and 4.0%) e three limestone particle size compositions (100% fine limestone (FL), with 0.185mm; 30% coarse limestone (CL), with 2.83mm, + 70% FL, with 0.185mm; and 50% CL, with 2.83mm, + 50% FL, with 0.185mm), with six replicates of eight birds each. Mean geometric diameter and in-vitro solubility of the limestone sources were, respectively, 0.185mm and 18.7% for the fine limestone, and 2.83mm and 10.5% for the coarse limestone. At the end of each 28-day period, 72 eggs per treatment were used to determine egg specific gravity, yolk percentage, albumen percentage, eggshell percentage, yolk index, Haugh units, eggshell thickness, and eggshell breaking strength. There was no influence of the treatments on the evaluated parameters. It was concluded that feeding the level of 3.5% calcium usually recommended for layers in their first laying cycle, and the substitution of up to 50% fine limestone by coarse limestone in the feed of semi-heavy commercial Hy-Line Brown layers in their second laying cycle can be applied with no impairment of egg quality.

Níveis de cálcio em dietas para poedeiras semipesadas após o pico de postura

Um experimento foi conduzido com o objetivo de estudar os efeitos dos níveis de cálcio nas rações sobre o desempenho e a qualidade de ovos de poedeiras comerciais. Foram utilizadas 216 poedeiras da linhagem Lohmann Brown no período de 39 a 55 semanas de idade. O delineamento utilizado foi inteiramente casualizado, composto de seis níveis de cálcio (3,0; 3,4; 3,8; 4,2; 4,6; 5,0%) e seis repetições de seis aves por parcela. Os níveis de cálcio avaliados não influenciaram os parâmetros produtivos, mas afetaram significativamente as porcentagens de albúmen e casca do ovo. O aumento do cálcio na dieta promove incremento na qualidade da casca do ovo em relação aos demais componentes do ovo. Recomenda-se nível de 4,3% de cálcio em dietas para poedeiras semipesadas após o pico de postura.

Exigência de cálcio para codornas japonesas (&lt;em&gt;coturnix coturnix japonica&lt;/em&gt;) em postura

This trial was performed to determine the requirements of calcium for Japanese quails during the laying period. A hundred and five quails were distributed in seven treatments and three repetitions. The treatments consisted of a basal diet supplemented with limestone in order to produce seven calcium levels (2.95; 3.10; 3.25; 3.40; 3.55; 3.70 and 3.85%). The following variables were evaluated: feed intake (CR), egg production (PD), egg mass (MO), conversion per egg mass (CMO), conversion per egg dozen (CDO), egg weight (PO), the weights and percentages of yolk, albumen and shell, and specific gravity. Calcium levels in the diet had no effect on CR and CMO. On the other hand, there was quadratic effect on PD, MO and CDO, and the maximum levels for these variables were estimated with calcium levels of 3.45; 3.51 and 3.34%, respectively. PO increased linearly with calcium levels in the diet. A quadratic effect of calcium levels was seen on the specific gravity and on weight and percentage of albumen and yolk. Calcium levels of 3.51% are recommended for Japanese quails during the laying period in order to optimize performance indexes without affecting negatively the internal and external egg quality.

Evaluation of Dietary Calcium Level and Fat Source on Growth Performance and Mineral Utilization of Heat-distressed Broilers

Male broilers (commercial strain) were used to evaluate the effects of diets differing in fat source on performance of heat-distressed broilers. Dietary treatments included corn oil (CO), animal fat (AF), fish oil (FO) and a dry blended (animal and vegetable) fat product (DB) at either 0.9 or 1.5 % calcium. Diets were isocaloric with each containing an equal number of calories from fats. Birds were reared in floor brooder pens and fed experimental diets from Day 1 to 21 and then assigned the same dietary treatments in one of two environmentally controlled chambers. One chamber was maintained at 23.9 C, whereas birds in the second o chamber were exposed to 8 hours of 23.9 C, 4 hours of 23.9 to 35 C, 4 hours of 35 C and 8 hours of 35 to 23.9 o o o C. At 42 days of age, plasma concentration of calcium and magnesium were higher (p > 0.01) in hea t o distressed (HD) birds than in their thermoneutral (TN) counterparts. Dietary calcium level, but not fat source, affected plasma calcium concentration. Temperature significantly (p < 0.05) affected the relative mineral retention (feed minus fecal mineral content) of magnesium while relative mineral retention of copper was affected by fat source. There was no effect of calcium level on performance but HD birds gained 31 % less weight than TN. Birds fed AF gained 10 % more than FO and 14 % more than DB. Data suggest that both fat source and environmental temperature influence mineral utilization and body weight gain.

Muscular degeneration in the absence of dystrophin is a calcium-dependent process

Duchenne muscular dystrophy (DMD) is a progressive degenerative muscular disease that is due to mutations in the dystrophin gene [1]. Neither the function of dystrophin nor the physiopathology of the disease have been clearly established yet. Several groups have reported elevated calcium concentrations in the mdx mouse model of DMD, but the effect of calcium levels on the progression of the disease continues to be a matter of debate [2–4]. Here, we show that, in Caenorhabditis elegans, a gain-of-function mutation in the egl-19 calcium channel gene dramatically increases muscle degeneration in dystrophin mutants. Conversely, RNAi-mediated inhibition of egl-19 function reduces muscle degeneration by half. Therefore, our results demonstrate that calcium channel activity is a critical factor in the progression of dystrophin-dependent muscle degeneration.

The Effect of Calcium Level on Microbial Phytase Activity and Nutrient Balance in Swine

The Effect of Calcium Level on Microbial Phytase Activity and Nutrient Balance in Swine

Effects of calcium level on the structure of pre-heated whey protein isolate gels

The effects of Ca level (10–360 mmol/L) on the gelation, at room temperature, of pre-heated whey protein isolate (100 g/L, pH 7.0) were investigated. At a low Ca concentration a clear gel was formed. Scanning and transmission electron micrographs (SEM, TEM) revealed the formation of a fine protein strand microstructure. As the Ca level increased, larger and thicker strands were formed. This was associated with a progressive reduction in the gel's clarity as was measured objectively with a colour meter. At 180 mmol/L Ca, TEM micrographs showed large aggregate formation which was associated with a significant reduction in water-holding capacity. Using 360 mmol/L Ca resulted in a gel similar to the 180 mmol/L treatment. Shear stress at fracture increased as the Ca level increased up to 180 mmol/L Ca and then levelled off. Shear strain decreased with the increase in Ca. The same was observed for water-holding capacity, indicating that the fine strand microstructure could hold moisture better than the aggregated structure. In a heat-induced gel (produced for comparison purposes) low Ca concentration (10 mmol/L) formed a typical opaque, aggregated gel. The water-holding capacity and shear stress values of the cold set gels were significantly higher than that of the heat-induced gels.

The effect of calcium levels on synaptic proteins. A study on VAT-1 from Torpedo

In this study we compare major synaptic proteins from Torpedo electric organ to their homologues from mammalian brain. Most of these proteins are members of small gene families. We demonstrate a high degree of evolutionary conservation of most synaptic proteins. However, in the electric organ each gene family is represented only by a single member. We focus on VAT-1, a major protein of the vesicle membrane in Torpedo. VAT-1 is located on the synaptic vesicle membrane and is highly concentrated on the plasma membrane following the application of α-latrotoxin. Taking advantage of the relative simplicity of Torpedo synapses, we performed an in vitro study on the properties of VAT-1 affected by changes in Ca 2+ levels. VAT-1 is a low affinity Ca 2+ binding protein whose ability to bind Ca 2+ resides mainly, but not entirely, on the carboxy-terminal domain of the protein. In the presence of Ca 2+, the protein is organized in a high molecular mass complex, which is destabilized by depleting Ca 2+. This effect occurs only by chelating Ca 2+ ions, but not with other divalent ions. VAT-1 is not complexed to any of the proteins which were implicated in the docking/fusion complex such as VAMP, synaptophysin or syntaxin, regardless of Ca 2+ levels. Dependence of the stability of protein complexes on Ca 2+ levels is also demonstrated on Torpedo n-Sec1. The possible physiological implications of such Ca 2+ dependence are discussed.

Effects of Calcium Level on Hypocalcaetnia and Associated Conditions in Dairy Cattle Fed Acidic Diets in the Late Dry Period

Recent research and field reports have shown a decreased incidence of milk fever and subclinical hypocalcemia when dairy cows are fed anionic salts. Researchers suggest feeding high levels of calcium when balancing for DCAD. Some producers have resisted adding more calcium to prepartum rations because of the fear it will cause more milk fever. The objective of this study was to determine if additional calcium supplementation is beneficial when feeding acidic rations prepartum. Two rations were compared with the same level of anionic salts, but different levels of calcium. From this study we are able to make some suggestions on calcium level and other aspects of using anionic salts to prevent milk fever.

Effect of calcium level in the feed on plasma calcium of chickens

Effect of calcium level in the feed on plasma calcium of chickens