Dietary Zinc Levels Research Articles

Decreased vascular contraction and changes in oxidative state in middle–aged Wistar rats after exposure to increased levels of dietary zinc

Both copper and zinc are known to be important for maintaining health, but most research has focused on deficiencies of these elements. Recent studies have shown that high levels of Cu can be toxic, especially to the cardiovascular (CV) system. However, little research has been done on the effects of higher levels of Zn on the CV system. In this study, male Wistar rats aged 12 months were given a diet with twice the recommended daily allowance of zinc (31.8 mg/kg of diet) and compared to a control group (15.9 mg/kg of diet) after 8 weeks. Blood plasma and internal organs of both groups were examined for levels of copper, zinc, selenium and iron, as well as several key enzymes. Aortic rings from both groups were also examined to determine vascular functioning. There were very few changes in the vascular system functioning after chronic exposure to zinc, and only one enzyme, heme oxygenase–1 (HO–1) was elevated, whereas vascular contraction to noradrenaline decreased with no changes in vasodilation to acetylcholine. Of the micronutrients, zinc and selenium were elevated in the blood plasma, while copper decreased. Meanwhile, the total antioxidant status increased. These were not observed in the liver. Therefore, it is proposed that there is a mechanism in place within the vascular system to protect against the overproduction of heme, caused by chronic zinc exposure.

Effects of dietary zinc on the gut microbiome and resistome of the gestating cow and neonatal calf

Zinc is an essential trace element required in the diet of all species. While the effects of zinc have been studied in growing calves, little is known about the effect of zinc on the microbiota of the gestating cow or her neonatal calf. Understanding factors that shape the gut health of neonatal animals and evaluating the effect of dietary supplements in adult gestating animals is important in promoting animal health and informing feeding practices. The aims of this study were to determine the effect of dietary zinc on the microbiota and resistome of the gestating cow and calf. Gestating cows received standard (40 ppm) or high (205 ppm) dietary zinc levels from dry off to calving. Fecal samples were collected from cows upon enrollment and at calving and from neonatal calves. Fecal samples underwent 16S rRNA sequencing and a subset also underwent shotgun metagenomic sequencing. The effect of zinc supplementation on the diversity and composition of the cow and calf microbiome and resistome was assessed. Alpha and beta diversity and composition of the microbiota were significantly altered over time but not by treatment in the cows, with alpha diversity decreasing and 14 genera found at significantly higher relative abundances at calving compared to enrollment. Levels of 27 antimicrobial resistance genes significantly increased over time. Only a small number of taxa were differentially expressed at calving in treatment and control groups, including Faecalibacterium, Bacteroides, Turicibacter, and Bifidobacterium pseudolongum. No effect of the dam’s treatment group was observed on the diversity or composition of the neonatal calf microbiota. The calf resistome, which was relatively rich and diverse compared to the cow, was also unaffected by the dam’s treatment group. The impact of high levels of dietary zinc thus appeared to be minimal, with no observed changes in alpha or beta diversity, and few changes in the relative abundance of a small number of taxa and antimicrobial resistance genes.

Adequate Levels of Zinc and Copper on Turkey Poult Performance, Immunological Response, and Skeletal Health.

In this study, the impact of varying dietary zinc (Zn) and copper (Cu) levels on the growth, immunological response, and skeletal health of developing turkey poults was investigated. For 0-4 and 5-8 weeks of age, respectively, three Zn levels of 50, 70, and 90mg/kg and 45, 65, and 85mg/kg were employed. Three Cu levels, namely 8, 12, and 16mg/kg for 0-8 weeks of age, were also utilized. There were 288 (9 × 4 × 8) day-old turkey poults with equal body weight that were randomly assigned to 9 treatments, each consisting of 4 replicates and 8 poults per replicate. In comparison to other dietary combinations, there was a significant (P ≤ 0.05) increase in body weight gain observed in the 90 and 85mg Zn/kg with 16mg Cu/kg diet during 0-4 and 0-8 weeks of age, respectively, and the 70 and 65mg Zn with 16mg Cu /kg diet during 0-4 and 0-8 weeks of age, respectively. When compared to low levels of zinc in the diet at 5-8 and 0-8 weeks of age, respectively, feed conversion ratio was shown to be significantly (P ≤ 0.01) better with 90 and 85mg Zn/kg diet. In a similar pattern, feed utilization efficiency was considerably (P ≤ 0.01) higher at 16mg Cu/kg diet than it was at lower Cu levels in the diets given to the animals over the 0-4 week period. Compared to other dietary combinations, there was a substantial (P ≤ 0.01) improvement in cell-mediated immune response (foot web index to PHAP) and humoral immune response (HA titer to SRBC) when 85mg zinc and 16mg copper/kg diet was consumed at 0-4 and 5-8 weeks of age. At greater dietary Zn and Cu levels than its lower values, the weight of the spleen and thymus was considerably (P ≤ 0.05) higher. In a dietary combination of 90mg Zn with 16mg Cu/kg during 0-4 and 85mg Zn with 16mg Cu/kg diet during 5-8 weeks of age, respectively, there were significantly (P ≤ 0.05) greater bone width (proximal and distal), tibia bone ash, calcium, and phosphorus detected respectively. Significantly (P ≤ 0.01) greater Zn and Fe contents were found in the tibia bone at 90 and 85mg Zn/kg diet, respectively, compared to values obtained at other Zn levels in the diet throughout 0-4 and 5-8 weeks of age. During the first 8 weeks of life, a diet containing 12mg of copper per kilogram was shown to have a significantly (P ≤ 0.05) increased Zn and Fe content in the tibia bone compared to other levels. It is possible to draw the conclusion from the data that, for growing turkey poults, dietary combinations of 90mg Zn/kg with 16mg Cu/kg diet and 85mg Zn with 16mg Cu/kg diet between 0 and 4 and 5-8 weeks of age, respectively, were sufficient for optimum development, immunity, and skeletal health indices.

The Association Between Psoriasis and Trace Element Serum Levels and Dietary Intake: Results from USA National Health and Nutrition Examination Survey 2011-2014.

Psoriasis is a common chronic inflammatory disease. However, trace elements are essential to biochemical processes of the skin, it is suspected that the trace elements are vital in the pathogenesis of psoriasis. Our research is aimed to investigate the association between serum levels and dietary intake levels of selenium, zinc, and copper with psoriasis. In this cross-sectional study, we utilized the National Health and Nutrition Examination Survey data from 2011 to 2014 to examine the association between psoriasis and serum concentration and dietary intake of trace elements including copper, zinc, and selenium in the US individuals. Our research combined two cycles and weighted the data. Student's t-tests and χ2 test were used. Subgroup analyses and interaction tests were conducted by IBM SPSS Statistics 22 and EmpowerStats. This study indicates that the population with psoriasis has a lower dose of dietary intake selenium than the controls, and risk analysis showed that the men with selenium daily intake >150 mcg/day have a decreasing risk for psoriasis compared to those with daily intaking selenium <75 mcg/day. However, there are no differences on daily intake of selenium, zinc, and copper and serum levels of Zinc and Copper between psoriasis and healthy controls. The current study showed that the psoriasis group was significantly older with a bigger waist circumference, a higher education level, a higher ratio of people with smoke every day, and a higher ratio of people in USA and being non-Hispanic White. This cross-section study showed that a high selenium intake may benefit USA adults from psoriasis, especially for males. The social and cultural background and ethnic differences between the two groups influence the eating and living models, including the trace element intake. The national recommended dietary allowances (RDAs) might be considered to be modified with more reliable investigative clinical data and certain considering the social and cultural models.

203 The relationship between potentiated zinc oxide and monovalent copper in a dietary administration for weanling piglets

Abstract The aim of this study was to evaluate different dietary level of Zinc (Zn) and Copper (Cu) supplementation according to European and non-European levels on the health and performance of pigs 14 d after weaning. A total of 120 piglets [initial body weight = 7.14 ± 0.92 kg] were divided into 4 experimental treatments: positive control (PC, 2,500 ppm of Zn, ZnO) and 3 treatments in which Zn and Cu were added through potentiated ZnO and Cu2O according to different European and non-European levels of inclusion: EU (120 ppm of Zn; 140 ppm of Cu), non-EU+ (300 ppm of Zn; 200 ppm of Cu) and non-EU- (300 ppm of Zn; 140 ppm of Cu). Growth performance, serum Zn and Cu concentrations, fecal score, blood biomarkers of intestinal integrity, and fecal microbial composition were examined and analyzed using GLM and MIXED procedures of SAS. Fecal samples at 14 d were collected and the V3–V4 hypervariable regions of the bacterial 16S gene were sequenced in one Illumina MiSeq run. Body weight (BW), average daily gain (ADG), average daily feed intake (ADFI), feed conversion ratio (FCR) and (feed efficiency (FE) were not affected by the experimental treatments. The fecal score suggests that during the first 14d, the consistency of the feces tended (P &amp;lt; 0.10) to be less in the three treatment groups while in PC, the greatest concentration of Zn favored a better fecal consistency. The initial serum Zn and Cu concentrations were similar for all dietary treatment groups. After 14 d, serum Zn concentration was significantly greater in PC (15.71 ± 6.25 µg/L, P &amp;lt; 0.05). No differences were highlighted in serum Zn concentration among the other 3 treatment groups. Serum Cu concentrations revealed statistically significant results (P &amp;lt; 0.05) on 14 d after weaning in EU, non-EU+ and non-EU- groups, showing greater concentrations of Cu (17.65 ± 5.49 µmol/L, 17.73± 3.46 µmol/L 18.33 ± 4.13 µmol/L, respectively) compared with PC (11.87 ± 3.60 µmol/L). These results suggested that the EU level of inclusion of both potentiated Zn and monovalent Cu is enough to reach the same Cu and Zn plasma concentrations of non-EU treatments. Plasma DAO was negatively (P &amp;lt; 0.05) affected in non-EU-. Firmicutes and Bacteroidetes were the most abundant phyla in fecal microbiome. Non-EU- contributed to a significant decrease in biodiversity in fecal microbiota as depicted with Shannon for diversity and Simpson for evenness indexes (P &amp;lt; 0.05). In fecal samples, the presence of genera linked to a greater disruption of the gut barrier (Escherichia-Shigella) was depicted in non-EU- group, indicating significant modifications of the microbial community. These results suggest the need for a balanced supplementation of Cu and Zn through more bioavailable sources. The use of potentiated ZnO and Cu2O according to European levels could represent a valid strategy to enhance weanling piglets gut health and to reduce the environmental impact.

202 Source matters: long-term effects of nursery sanitary condition and dietary Zinc source and level on growth performance, diarrhea incidence, and carcass metrics of pigs

Abstract There is growing evidence that requirements for particular nutrients increase when pigs are kept under low sanitary conditions (LSC). It may be hypothesized that dietary zinc (Zn) source can exert influence on immune status, which may influence resistance to subclinical and clinical diseases. The objective was to investigate the long-term effects of nursery sanitary condition and dietary Zn source and growth performance, diarrhea incidence, and carcass metrics of pigs. An experiment was performed with 480 mixed-sex weanling pigs (initial body weight = 6.4 ± 0.38 kg) which were assigned to 1 of 5 treatments during the nursery (42 d) as follows: 1) pigs housed in high sanitary conditions (HSC) and fed 50 mg/kg Zn from Zn-amino acid complex (ZnAA), pigs housed in LSC and fed either 2) 50 mg/kg Zn from ZnAA, 3) 100 mg/kg Zn from ZnAA, 4) 100 mg/kg Zn and 0.4 mg/kg chromium (Cr) from Zn+Cr-amino acid complex (Zn+CrAA), or 5) 100 mg/kg Zn from inorganic Zn (ZnSO4). Pigs were then placed onto a common grower (42 d) and finisher (42 d) diets and housed under similar, standard conditions and were monitored until slaughter. Growth performance, diarrhea incidence, and carcass characteristics were assessed. Pigs housed in LSC and fed 100 mg/kg from ZnSO4 had less average daily feed intake (ADFI) during wk 1 and 2 of nursery (0.29 vs. 0.33 ± 0.01 kg/d; P &amp;lt; 0.05) and poorer feed to gain (FGR) during wk 3 and 4 of nursery (1.76 vs. 1.54 ± 0.03 kg/kg; P &amp;lt; 0.05), compared with the other groups. Overall nursery FGR was poorer in pigs housed in LSC and fed 100 mg/kg from ZnSO4 compared with the other groups housed in LSC (1.63 vs. 1.54 ± 0.02 kg/kg; P &amp;lt; 0.05). Diarrhea incidence tended to increase in all groups housed in LSC compared with the group housed in HSC during week 1 of nursery (91.1 vs. 80.4 ± 3.11%; P &amp;lt; 0.10), while no effect on diarrhea incidence was observed during the subsequent week (P &amp;gt; 0.10). Slaughter weight was increased in pigs housed in LSC and fed 100 mg/kg Zn and 0.4 mg/kg Cr from Zn+CrAA compared with pigs housed in LSC and fed 100 mg/kg from ZnSO4 (123.4 vs. 120.1 ± 0.63 kg; P &amp;lt; 0.05). Housing pigs in LSC during the nursery seems to trigger negative effects on growth performance and diarrhea incidence during nursery only, but these effects do not seem to be translated into the grower and finisher phases. Feeding ZnAA and Zn+CrAA aid the pigs in responding to LSC during nursery and may be an approach to help minimize negative effects of immune system stimulation.

Dietary zinc deficiency increases damage rate and copy number of mitochondrial DNA in the mouse liver

Zinc is an essential trace element involved in many physiological processes, ranging from cellular growth and immune functions to enzymatic activity and gene expression. Inadequate dietary zinc levels can disrupt the functioning of numerous organs, including the liver. Given the pivotal role played by the liver, in-depth understanding of the mechanisms driving disorders in this organ caused by zinc deficiency is of great importance. In the present study, the effects of a four-week low-zinc diet on the integrity and copy number of mitochondrial DNA (mtDNA) in the liver was assessed using a mouse model. The research revealed a significantly elevated damage rate and an increased copy number of mtDNA in the livers of mice subjected to a low-zinc diet when compared to control animals. These findings indicate that a zinc deficiency, by promoting DNA damage in mitochondrial genomes, increases a potential risk of harmful mutations that could compromise ATP production in the liver. The rise in the mtDNA copy number suggests an initial compensatory response to the detrimental effects of the zinc deficiency, which is likely to diminish with a chronic insufficiency of this element. The study confirmed the significant role of mitochondria in the processes leading to liver dysfunction induced by a zinc deficiency. It showed additionally that mtDNA is a very sensitive indicator of the liver's condition that is responsive to environmental changes such as a micronutrient deficiency in the diet.

Effect of feeding different dietary levels of zinc and iron on growth performance immune response and hematological parameters of growing Turkey poults

Effect of feeding different dietary levels of zinc and iron on growth performance immune response and hematological parameters of growing Turkey poults

Impact of dietary zinc and copper levels on ileal and total apparent nutrient digestibility in growing pigs

This study aimed to evaluate the effect of dietary zinc (Zn) and copper (Cu) levels on their apparent ileal digestibility (AID) and total tract digestibility (ATTD) and that of calcium (Ca), manganese (Mn), iron (Fe), phosphorus (P), and fiber in pigs. The experiment was carried out with six individuals fitted with a T-cannula. Pigs received one of four diets with two levels of Zn (100 [low] and 500 [high] mg/kg) and Cu (40 [low] and 80 [high] mg/kg). High Zn increased AID of Zn and Mn, but decreased that of Ca ( p &lt; 0.05). High Cu tended to improve AID of Cu, but only when high Zn was used (Interaction Zn × Cu, p = 0.051). ATTD of Zn, Cu, Mn, and P was greater in high Zn ( p &lt; 0.05). High Cu also increased ATTD of Cu, but reduced that of Ca ( p &lt; 0.05) as it likely did for ATTD of P in low Zn (Interaction Zn × Cu, p = 0.065). There was an improving trend for ATTD of NDF (Interaction Zn × Cu, p = 0.069), and ATTD of ADF was increased with a combination of high Zn and high Cu (Interaction Zn × Cu, p &lt; 0.05). This research showed that the levels of Cu and Zn modified the digestibility of minerals but also the degradability of fiber.

Association between maternal zinc intake and preterm birth in Gansu Province in 2010-2012

To analyze the association between maternal dietary zinc levels at different stages and preterm birth. The subjects were from the 2010-2012 birth cohort of Maternal and Child Health Hospital of Gansu Province, and a total of 10 179 pregnant women were included in the final study. Dietary information before and during pregnancy was collected through semi-quantitative food frequency questionnaire, and daily zinc intake in each period was estimated according to the frequency of consumption and portion size of food items using the Chinese Standard Tables of Food Consumption. Logistic regression was used to analyze the OR value of preterm birth under different maternal dietary zinc levels. The detection rate of preterm birth was 10.0%, of which 81.8% were moderate preterm, 18.3% were very preterm, 33.2% were medically indicated preterm and 66.8% were spontaneous preterm birth. After adjusting for general conditions such as maternal age, education level, and history of preterm birth, compared with the group with the highest zinc intake before and during pregnancy, those with low zinc intake before or during pregnancy had a significantly higher risk of moderate, very, and spontaneous preterm birth. After further controlled of folic acid and fiber intake during pregnancy, compared with the group with the highest zinc intake before and during pregnancy, the risk of very preterm birth(OR=2.04, 95%CI 1.07-3.90) and spontaneous preterm birth(OR=1.38, 95%CI 1.01-1.88) was significantly increased in those with the lowest zinc intake during the third trimester. For pregnant women aged≥30 years(OR=1.55, 95%CI 1.12-2.13) and normal or less normal weight gain during pregnancy(OR=1.51, 95%CI 1.15-1.97), insufficient zinc intake was significantly associated with preterm birth. Maternal low dietary zinc intake during the third trimester was associated with very premature and spontaneous preterm birth.

Could commercial meal kits be part of the solution to food insecurity during pregnancy? An Australian exploratory study.

To explore the nutritional content of meal kits from two main Australian companies over a 6-week period against healthy eating guidelines for pregnancy. Across the 6-week period, weekly meal kits from both Provider 1 and Provider 2 were purchased, 36 individual meals were assessed. All data were analysed for the development of a macronutrient and micronutrient profile of meals. Extracted data were macronutrient, vitamin, and mineral composition, which were compared against the healthy eating guidelines for pregnant women in Australia and New Zealand. Meal kits include higher levels of sodium, and lower levels of dietary fibre, calcium, magnesium, zinc, iron, thiamin, riboflavin, grains, and dairy when compared against the guidelines for healthy eating for pregnant women in Australia and New Zealand. Meal kits may increase meals prepared and consumed in the home, and thanks to the clear instructions and pre-portioned ingredients, may reduce stress related to food preparation. They have the potential to provide nutritionally adequate meals to pregnant women as a way to mitigate food insecurity or hunger during pregnancy and may provide some nutritional benefits and have the potential to remove some of the challenges with maintaining an adequate diet when pregnant.

Dietary zinc levels affect growth, appetite, and lipid metabolism of Chinese perch (Siniperca chuatsi).

An 84-day feeding experiment was conducted to investigate the effects of dietary Zn (zinc) on growth performance, food intake, and lipid metabolism of Chinese perch (Siniperca chuatsi). Five isonitrogenous and isolipidic diets with differential Zn contents (67, 100, 149, 230, and 410mg/kg) were fed to 270 fish (35.47 ± 0.49g). Results showed that fish growth and food intake increased markedly with the dietary 149mg/kg Zn levels. Meanwhile, the food intake of 149mg/kg group was significantly higher than that of other treatment groups after feeding for 8weeks (P < 0.05). The qRT-PCR results showed that the expression of center appetite regulation factors in the hypothalamus was significantly regulated, and 149mg/kg significantly increased mRNA expression of npy (neuropeptide Y) and decreased pomc (anorexigenic proopiomelanocortin) and cart (cocaine- and amphetamine-regulated transcript) gene expression. Meanwhile, the expressions of the main genes (such as leptin A and ghrelin) involved in peripheral appetite regulation factors were significantly up-regulated firstly and then reduced with the dietary Zn level increased, whereas the expression of cck (cholecystokinin) was significantly up-regulated. Serum AST (aspartate transaminase) and ALT (alanine transaminase) activities in fish fed the diets containing 230 and 410mg/kg were significantly higher than that in other groups (P < 0.05). The lipid content of liver in 67 and 100mg/kg groups was significantly higher than other groups (P < 0.05). Furthermore, dietary Zn significantly elevated the serum TG (triglyceride) and TCHO (total cholesterol) content levels (P < 0.05). Fish fed a high Zn diet (149, 230, and 410mg/kg) dramatically down-regulated expression of srebp1 (sterol regulatory element binding proteins1c) and fas (fatty acid synthetase), but up-regulated expression of pparα (peroxisome proliferators-activated receptor-α) and cpt1 (carnitine palmitoyl transferase I) in the liver. The optimal dietary Zn inclusion level ranged from 146.69 to 152.86mg/kg diet, based on two-slope broken-line regression analysis of WGR (weight gain rate) and FCR (feed conversion rate) for Chinese perch.

Impact of dietary zinc on the growth performance, histopathological analysis, antioxidant capability, and inflammatory response of largemouth bass Micropterus salmoides

Zinc plays a crucial role in the antioxidant capacity, and inflammatory response of aquatic species, but its impact on largemouth bass Micropterus salmoides is rarely reported. Therefore, this paper aimed to investigate the effects of different levels of zinc on the growth performance, histopathology, antioxidant capacity, and inflammatory cytokines of largemouth bass Micropterus salmoides. Fish with an initial weight of 7.84 ± 0.06 g were cultured for 10 weeks. Five experimental diets were prepared with supplemented proteinate Zn (Bioplex Zn, Alltech) (0, 30, 60, 90, and 120 mg/kg), which were named the Zn-42, Zn-73, Zn-103, Zn-133, and Zn-164 groups. No evident difference was found between the dietary zinc level and the survival rate, the crude lipid content of the whole fish, or the visceral somatic index. Weight gain, condition factor, whole-body crude protein content, interleukin-10, and transforming growth factor beta gene expression were gradually enhanced with up to 102.68 mg/kg zinc and decreased at higher levels. The hepatosomatic index, feed conversion ratio, malondialdehyde level in the liver, aspartate aminotransferase, and alanine transaminase activity in the serum, gradually decreased up to 102.68 mg/kg zinc, and gradually increased beyond this. Activation of the nuclear factor erythroid-derived 2-like 2/Kelch-like ECH-associated protein 1 signaling pathway gradually up-regulated the mRNA levels and activities of glutathione peroxidase, total antioxidant capacity, catalase, and superoxide dismutase in the liver, this antioxidant ability was lower when the zinc was greater than 102.68 mg/kg. The gene expressions of nuclear factor-k-gene binding and pro-inflammation cytokines (interleukin-1β, interleukin-15, tumor necrosis factor alpha, and interleukin-8) were up-regulated up to 102.68 mg/kg zinc and then gradually repressed. In conclusion, using broken line analysis to estimate weight gain and Zn proteinate as the zinc source, the recommended dietary zinc for largemouth bass is 66.57 mg/kg zinc.

Effects of dietary zinc levels on growth, intestinal health, antioxidant and non-specific immunity of spotted seabass (Lateolabrax maculatus) reared at two temperatures

This study investigated effects of dietary zinc levels and water temperature on growth, feed utilization, intestinal health, antioxidant and non-specific immunity of spotted seabass. Six experimental diets were formulated to contain 30, 53, 77, 98, 116, or 145 mg Zn/kg. Each diet was fed to two different groups of fish reared at low temperature (27 °C; LT) or high temperature (33 °C; HT). Triplicate groups of fish were fed the test diets to apparent satiation two times daily for 8 weeks. Results showed that fish under HT showed the lower weight gain (WG) and higher feed conversion rate (FCR) comparing to the LT treatment (P < 0.05). Also, the growth and feed utilization were significantly (P < 0.05) influenced by dietary Zn levels and broken-line regression analysis showed the optimal dietary Zn level for spotted seabass reared at 27 °C and 33 °C are 77.69 mg/kg and 93.61 mg/kg, respectively. Apparent digestibility coefficients (ADCs) of protein and lipid in HT treatment were significantly lower than those of LT treatment (P < 0.05), and ADCs significantly increased with the increase of dietary Zn levels. The histology showed HT and Zn-deficiency can cause the damage of intestine, while fish fed 77 mg Zn/kg diets presented normal structure. Serum LZM activity, C3 and IgM contents of HT treatments were lower than those of the LT treatments. Further, LZM activity, C3, and IgM contents can be significantly elevated by the increasing of dietary Zn levels. MDA content of HT treatments were significantly higher than that of LT treatments, while MDA content decreased with the increase of dietary Zn levels as SOD activity and T-AOC increased. Overall, the optimum dietary Zn level alleviated heat stress via enhancing immunity, antioxidant capacity and intestine health.

Dietary selenium and zinc supplementation alters growth and immunity of broiler chicken

This study evaluated the influence of varying dietary levels of selenium (Se) and Zinc (Zn) on the performance index, carcass characteristics, and immune response in broiler chicken. The experimental trial was carried for 42 days with a 3 × 3 factorial design involving three levels of each Se (0.15, 0.30, and 0.45 mg/kg diet) and Zn (40, 80, and 120 mg/kg diet) resulting in nine treatments. Six replicate groups with eight birds in each were assigned to each treatment (48 birds/treatment). During starter phase (0-3 weeks), optimum growth performance and growth efficiency of chicken was observed at 0.30 mg Se/kg diet. However, during finisher phase (4-6 week) and overall growth phase (0-6 week), 0.15 mg Se/kg diet was found to be optimum. Similarly, weight gain during starter phase was higher in birds fed at least 80 mg Zn/kg diet. The carcass characteristics did not reveal significant effect of Se and Zn supplementation in broiler chicken. And, on similar lines, cell mediated immunity remained unaffected. However, better humoral immunity was observed in birds supplemented with NRC recommended Se level in diet, but the NRC recommendation of 40 mg Zn/kg diet was inadequate for better humoral immune response compared to 80 or 120 mg level. Further, higher spleen and thymus weight was observed at 0.3 mg Se/kg diet and higher spleen weight at 80 mg Zn/kg diet. In conclusion, Se supplementation of 0.30 mg /kg diet and Zn supplementation of 80 mg/kg diet resulted in optimum growth performance, efficiency, and immunity of broiler chicken.

Effects of dietary zinc (Zn) levels on growth performance, nutrient composition, muscle development, antioxidant and inflammatory responses in yellow catfish muscle

Three diets were formulated with dietary zinc (Zn) levels at 12.10 mg Zn/kg (L-Zn), 18.69 mg Zn/kg (M-Zn) and 120.82 mg Zn/kg (H-Zn) to explore effects of dietary Zn on growth, nutrient composition, muscle development, antioxidant and inflammatory responses in the muscle tissues of yellow catfish, one of the important economic fish in several Asian countries, including China. Zn content in M-Zn group could meet Zn requirement of yellow catfish. 270 juvenile yellow catfish (4.97 ± 0.01 g, mean ± S.E.M) were stocked in nine 300-L indoors tanks, 30 yellow catfish in each tank, and randomly provided with three diets for 10 weeks. Among three treatments, yellow catfish fed the middle Zn diets showed higher growth performance and condition factor but lower feed conversion rate than those fed the high Zn diets. Dietary Zn addition increased muscle Zn contents, but did not significantly influence feed intake, viscerosomatic and hepatosomatic index, survival, moisture, lipid, crude protein and ash contents in the muscle. Dietary Zn levels significantly influenced mRNA expression of several muscle development-related genes, such as mef2a, myod, myf5, myog, mef2d, pax7, mrf4, myhc and mstn. Middle dietary Zn levels increased antioxidant capability and reduced oxidative stress, as evaluated by enzymatic activities, gene and protein expression related to antioxidant response. Fish fed the middle Zn diets had the lower il8, tnf-α and tnf-β mRNA expression but higher il10 and tgf-β mRNA expression than those fed the high Zn diet, suggesting that optimal dietary Zn levels activated anti-inflammatory response and inhibited pro-inflammatory responses. Based on the observation, our study suggested that the suitable dietary Zn levels promoted the growth, muscle development, antioxidant and anti-inflammatory responses in fish.

Assessment of serum, dietary zinc levels, and other risk factors during the third trimester among pregnant women with and without pregnancy-induced hypertension: a case-control study.

This study assessed serum, dietary zinc levels, and other risk factors during the third trimester among pregnant women with and without pregnancy-induced hypertension (PIH). This case-control study was conducted in 2022, in the three main Obstetrics and Gynecology departments in Gaza Strip, Palestine. One hundred sixty pregnant women, during the third trimester, aged ≥20 years, were selected using a convenient sampling method. Data were obtained using an interview-based questionnaire, food frequency questionnaire, anthropometric measures, and biochemical tests. Statistical analysis was performed using SPSS version 24. The participants' mean age was 30.7 ± 5.6 years. A total of 47 (58.8%) of cases and 6 (7.5%) of controls were insufficiently active; and the mean of blood pressure (mmHg) was 133.3 ± 11.9/85.11 ± 10.0 for cases and 112.8 ± 9.5/68.02 ± 7.2 for controls with significant differences between the two groups (P = <0.005). The mean serum zinc level (μg/dl) was 67.15 ± 16.5 for cases and 68.45 ± 18.0 for controls without significant differences between the two groups (P = 0.636). For newborns, the mean birth weight (g) was 2,904.6 ± 486 for cases, and 3,128.3 ± 501 for controls, and the mean Apgar score was 8.03 ± 0.62 for cases and 8.30 ± 1.17 for controls, with significant differences between the two groups (P = <0.005). Furthermore, 43 (53.8%) of cases have family history of hypertension; 5 (6.2%) were primiparous; 19 (23.8%) have previous caesarian section; 33 (41.2%) have history of preeclampsia; and 62 (77.5%) have edema, with significant differences between the two groups (P = <0.005). Additionally, the total zinc dietary daily intake (mg/day) was 4.15 ± 2.10 for cases and 4.88 ± 3.02 for controls, with significant differences between the two groups (P = 0.041). After adjustment for confounding variables, participants in the case group have higher odds of having low total zinc dietary intake compared to those in the control group [OR = 1.185, 95% CI = (1.016-1.382), P = 0.030]. The current study showed the main risk factors of PIH among pregnant women in the Gaza Strip, Palestine. Furthermore, low maternal dietary zinc intake was associated with a high level of PIH. Moreover, having PIH could increase the risk of low birth weight and low Apgar scores. Therefore, reducing the main risk factors of PIH could reduce the adverse effect on both mother and birth outcomes.

Fear-of-intimacy-mediated zinc transport is required for Drosophila fat body endoreplication

BackgroundEndoreplication is involved in the development and function of many organs, the pathologic process of several diseases. However, the metabolic underpinnings and regulation of endoreplication have yet to be well clarified.ResultsHere, we showed that a zinc transporter fear-of-intimacy (foi) is necessary for Drosophila fat body endoreplication. foi knockdown in the fat body led to fat body cell nuclei failure to attain standard size, decreased fat body size and pupal lethality. These phenotypes could be modulated by either altered expression of genes involved in zinc metabolism or intervention of dietary zinc levels. Further studies indicated that the intracellular depletion of zinc caused by foi knockdown results in oxidative stress, which activates the ROS-JNK signaling pathway, and then inhibits the expression of Myc, which is required for tissue endoreplication and larval growth in Drosophila.ConclusionsOur results indicated that FOI is critical in coordinating fat body endoreplication and larval growth in Drosophila. Our study provides a novel insight into the relationship between zinc and endoreplication in insects and may provide a reference for relevant mammalian studies.

Interaction Between Dietary Selenium and Zinc Intakes on Hypothyroidism.

This study assessed the independent association of dietary selenium and zinc intakes with the risk of hypothyroidism and interaction effect between dietary selenium and zinc intakes with the risk of hypothyroidism in Americans. The data of this cross-sectional study was from the National Health and Nutritional Examination Survey (NHANES) 2007-2012. The outcome was defined as new-onset hypothyroidism. Weighted univariate and multivariate logistic regression and the subgroup analyses based on gender and body mass index (BMI) were conducted to evaluate the association between the dietary selenium and zinc intakes and new-onset hypothyroidism. Odds ratio (OR) and 95% confidence interval (CI) were calculated. A total of 6402 participants were included with 131 (2.05%) developed a hypothyroidism in this study. Compared with participants with high zinc intake, those with low zinc intake had a higher risk of new-onset hypothyroidism (OR = 1.74, 95% CI: 1.05-2.90). Moreover, we also found a significant interaction between dietary selenium level intake and dietary zinc level intake on new-onset hypothyroidism risk (OR = 5.99, 95% CI: 1.77-20.23). There was an interaction between dietary selenium and zinc intakes on the risk of new-onset hypothyroidism, especially the significant effect for adults with women or overweight. The findings indicated that improving the levels of dietary zinc and selenium intake may be beneficial in preventing of new-onset hypothyroidism.

Dietary Intake Levels of Iron, Copper, Zinc, and Manganese in Relation to Cognitive Function: A Cross-Sectional Study.

Background: Previous studies have related circulating levels of trace metal elements, of which dietary intake is the major source, to cognitive outcomes. However, there are still relatively few studies evaluating the associations of dietary intake levels of iron, copper, zinc, and manganese with cognitive function (CF). Methods: We leveraged the data of 6863 participants (mean [standard deviation] age = 66.7 [10.5] years) in the Health and Retirement Study (2013/2014). Dietary intake levels of iron, copper, zinc, and manganese were calculated from a semi-quantitative food frequency questionnaire. CF was assessed using the 27-point modified Telephone Interview for Cognitive Status (TICS). We used linear regression models to calculate the mean differences in global CF scores by quintiles of dietary intake levels of trace metal elements. Results: Among the study participants, the mean (SD) values of daily dietary intake were 13.3 (6.3) mg for iron, 1.4 (0.7) mg for copper, 10.7 (4.6) mg for zinc, and 3.3 (1.6) mg for manganese. Compared with the lowest quintile of dietary iron intake (<8.1 mg), the highest quintile (≥17.7 mg) was associated with a lower cognitive score (-0.50, -0.94 to -0.06, P-trend = 0.007). Higher dietary copper was significantly associated with poorer CF (P-trend = 0.002), and the mean difference in cognitive score between extreme quintiles (≥1.8 vs. <0.8 mg) was -0.52 (95% confidence interval: -0.94 to -0.10) points. We did not observe significant associations for dietary intake of zinc (P-trend = 0.785) and manganese (P-trend = 0.368). Conclusion: In this cross-sectional study, higher dietary intake of iron and copper was related to worse CF, but zinc and manganese intake levels were not significantly associated with CF.