Effect of supplemental dietary chromium or nicotinic acid on carbohydrate metabolism during basal, starvation, and refeeding periods in poults

Chromium propionate in turkeys: effect on performance and animal safety

Two hundred eighty-eight male Nicholas Large White turkey poults were used to determine the effect of supplementing turkeys with chromium propionate (Cr Prop) from 1 to 84 d of age on performance and animal safety. Treatments consisted of Cr prop supplemented to provide 0, 0.2, or 1.0 mg Cr/kg diet. One mg of supplemental Cr is 5 times (x) the minimal concentration of Cr Prop that enhanced insulin sensitivity in turkeys. Each treatment consisted of 8 floor pens with 12 poults per pen. Turkeys were individually weighed initially, and at the end of the starter 1 (d 21), starter 2 (d 42), grower 1 (d 63), and grower 2 phase (d 84). On d 85, blood was collected from the wing vein in heparinized tubes from 2 turkeys per pen for plasma chemistry measurements. A separate blood sample was collected from the same turkeys in tubes containing K2EDTA for hematology measurements. Turkey performance was not affected by treatment during the starter 1 phase. Gain was greater (P = 0.024) and feed/gain lower (P = 0.030) for turkeys supplemented with Cr compared with controls during the starter 2 phase. Over the entire 84-d study turkeys supplemented with Cr had greater (P = 0.005) ADG and tended (P = 0.074) to gain more efficiently than controls. Gain (P = 0.180) and feed/gain (P = 0.511) of turkeys supplemented with 0.2 mg Cr/kg did not differ from those receiving 1.0 mg Cr/kg over the entire 84-d study. Feed intake was not affected by treatment. Body weights of turkeys supplemented with Cr were heavier (P = 0.005) than controls by d 84. Chromium supplementation did not affect hematological measurements and had minimal effect on plasma chemistry variables. Results of this study indicates that Cr Prop supplementation can improve turkey performance, and is safe when supplemented to turkey diets at 5x the minimal concentration that enhanced insulin sensitivity.

Chromium propionate in turkeys: effects on insulin sensitivity

The objective of this study was to evaluate the effects of dietary chromium (Cr), as Cr propionate (Cr Prop), on measures of insulin sensitivity in turkeys. Plasma glucose and nonesterified fatty acid (NEFA), and liver glycogen concentrations were used as indicators of insulin sensitivity. One-day-old Nicholas Large White female poults (n = 336) were randomly assigned to dietary treatments consisting of 0 (control), 0.2, 0.4, or 0.6 mg supplemental Cr/kg diet. Each treatment consisted of 12 replicate cages with 7 turkeys per cage. Final BW were taken on d 34, and on d 35 two birds from each cage were sampled for plasma glucose and NEFA, and liver glycogen determination at the initiation (fed state) and termination (fasted state) of a 24-h fast. Following a 24-h fast, 2 turkeys per cage were refed (refed state) their treatment diet for 4 h, and then harvested. Feed/gain and ADG did not differ between control and Cr-supplemented turkeys over the 34-d study, but feed intake tended (P = 0.071) to be greater for controls than turkeys receiving 0.4 mg Cr/kg diet. Fed turkeys had greater plasma glucose (P = 0.002) and liver glycogen (P = 0.001) concentrations, and lower (P = 0.001) NEFA concentrations than fasted birds. Turkeys refed after fasting had greater (P = 0.001) plasma glucose and liver glycogen concentrations, and lower (P = 0.001) plasma NEFA levels than fed turkeys. Liver glycogen and plasma NEFA concentrations did not differ among control and Cr-supplemented birds in the fed, fasted, or refed state. Plasma glucose concentrations were not affected by treatment in fed or fasted turkeys. Turkeys supplemented with 0.2 or 0.4 mg Cr/kg and refed after fasting had lower (quadratic, P = 0.038) plasma glucose concentrations than controls. Plasma glucose concentrations in refed birds did not differ among Cr-supplemented turkeys. The lower plasma glucose concentration in Cr-supplemented turkeys following refeeding is consistent with Cr enhancing insulin sensitivity.

Investigation of Different Nutritional Effects of Dietary Chromium in Fish: A Literature Review

The supply of food for the world population that is increasing is one of the concerns of governments. The Food and Agriculture Organization of the United Nations assessment shows that the aquaculture industry could help meet food needs for human communities. The aquaculture industry also relies on providing a feed of high quality. Minerals are one essential component of an aquatic diet. Chromium (Cr) is a trace element that finds the form of Cr⁺³ (trivalent) and Cr⁺⁶ (hexavalent) in nature and food items. Studies show that exposure to Cr waterborne have toxicity effects on fish. However, oral exposure to Cr has a different impact on fish. Cr is usually involved in the metabolism of fats, carbohydrates, proteins, growth function, enzyme functions, etc. This element could play a significant role in fish nutrition and physiology. Cr as a dietary supplement can improve growth performance and adjust the metabolism of carbohydrates and lipids. However, high concentrations of Cr can be toxic to fish. Although the physiological effects of Cr on aquatic organisms are well known, there are still ambiguities in determining the appropriate concentration in the diet of some species. Maybe, the physiological response of fish depends on the concentration, origin, and chemical composition of Cr, as well as the biological and individual characteristics of the fish. Therefore, it is necessary to estimate the appropriate concentration of Cr in fish diets. This article aims to summarize the available information about the effect of Cr on various physiological indicators and fish growth. Therefore, this information may help to find the appropriate concentration of Cr in the diet.

Effects of Dietary Chromium Picolinate on Gut Microbiota, Gastrointestinal Peptides, Glucose Homeostasis, and Performance of Heat-Stressed Broilers

The current research was devoted to evaluating the effects on gut microbiota, gastrointestinal peptides, and glucose homeostasis of chromium picolinate applied to heat-stressed broilers. In a 14 d experiment, 220 28-day-old AA broilers were randomly assigned into one thermal-neutral and three high-temperature groups dietary-supplemented with 0, 0.4, or 0.8 mg/kg of chromium as chromium picolinate. The temperature for the thermal-neutral group was set at 21 °C, while that for the other three groups (high temperature) was set at 31 °C. The results showed that the average daily gain and average daily feed intake of the 0.4 mg/kg chromium-supplemented group significantly increased compared with the high-temperature groups (p < 0.05). The content of cholecystokinin in the 0.4 mg/kg group significantly decreased, and the gastric inhibitory polypeptide level was significantly elevated in jejunum (p < 0.05). The cecal microbiota of heat-stressed broilers was substantially different from that of the thermal-neutral group. After diet-supplemented chromium, compared to the high-temperature groups, the 0.4 mg/kg chromium supplemented group was characterized by a reduction of Actinobacteriota and Proteobacteria at the phylum level. The Bacilli were elevated, while proportions of Coriobacteria and Gammaproteobacteria were reduced significantly at the class level. The proportions of Lactobacillaceae, Christensenellaceae, and Erysipelotrichaceae were elevated significantly, while that of Clostridiaceae was reduced significantly at the family level. The proportion of Turicibacter was elevated significantly and the proportions of Olsenella and Ruminococcus were reduced significantly at the genus level (p < 0.05). Compared to the high-temperature groups, in the 0.4 mg/kg chromium-supplemented group, the insulin concentration and insulin resistance index were reduced (p < 0.05), and sodium-glucose transporter 1 expression was up-regulated in jejunum (p < 0.05). Performance, microbiota, gastrointestinal peptides, or serum parameters of the 0.8 mg/kg group were almost unaffected by chromium compared with the high-temperature groups. In conclusion, diet supplemented with 0.4 mg/kg Cr improved performance, insulin resistance and sodium-glucose transporter 1 expression and altered gut microflora structure and secretion of gastrointestinal peptides, thus showing that supplementation with chromium is beneficial to maintain glucose homeostasis and alleviate heat stress.

The Role of GPR109a Signaling in Niacin Induced Effects on Fed and Fasted Hepatic Metabolism

Signaling through GPR109a, the putative receptor for the endogenous ligand β-OH butyrate, inhibits adipose tissue lipolysis. Niacin, an anti-atherosclerotic drug that can induce insulin resistance, activates GPR109a at nM concentrations. GPR109a is not essential for niacin to improve serum lipid profiles. To better understand the involvement of GPR109a signaling in regulating glucose and lipid metabolism, we treated GPR109a wild-type (+/+) and knockout (-/-) mice with repeated overnight injections of saline or niacin in physiological states characterized by low (ad libitum fed) or high (16 h fasted) concentrations of the endogenous ligand, β-OH butyrate. In the fed state, niacin increased expression of apolipoprotein-A1 mRNA and decreased sterol regulatory element-binding protein 1 mRNA independent of genotype, suggesting a possible GPR109a independent mechanism by which niacin increases high-density lipoprotein (HDL) production and limits transcriptional upregulation of lipogenic genes. Niacin decreased fasting serum non-esterified fatty acid concentrations in both GPR109a +/+ and -/- mice. Independent of GPR109a expression, niacin blunted fast-induced hepatic triglyceride accumulation and peroxisome proliferator-activated receptor α mRNA expression. Although unaffected by niacin treatment, fasting serum HDL concentrations were lower in GPR109a knockout mice. Surprisingly, GPR109a knockout did not affect glucose or lipid homeostasis or hepatic gene expression in either fed or fasted mice. In turn, GPR109a does not appear to be essential for the metabolic response to the fasting ketogenic state or the acute effects of niacin.

Improvement in the growth status and carbohydrate utilization of Labeo rohita (Hamilton, 1822) fingerlings with dietary supplementation of chromium picolinate

A 60-day feeding experiment was conducted to evaluate the effects of dietary chromium (Cr) on carbohydrate utilization and growth performance of Labeo rohita fingerlings. Fishes were fed with four high carbohydrate (53%), isonitrogenous (crude protein 35%), and isocaloric (415 Kcal, 100 gm^-1) experimental diets containing different levels of dietary chromium picolinate (Cr-Pic) viz.0, 400, 800, and 1200 μg kg^-1 diet. Weight gain (WG%), specific growth rate (SGR), feed efficiency ratio (FER), and protein efficiency ratio (PER) were significantly increased at 800 μg kg^-1 diet chromium supplementation (P < 0.05). Cr-Pic supplementation (800 μg kg^-1) also significantly (P < 0.05) enhanced the protein: DNA ratio in muscle, while DNA: RNA and DNA: tissue ratios were significantly (P < 0.05) decreased indicating higher growth. Significantly higher amylase, protease, and lipase activities were recorded in 800 μg Cr-Pic kg^-1 diet fed fishes (P < 0.05), while any of the experimental groups showing no significant (P > 0.05) change in hexokinase activity, indicating normal glycolysis in all. Furthermore, significant (P < 0.05) decrease of glucose-6-phospatase activity in 800 μg Cr-Pic kg^-1 diet fed group, showcasing an evidence for protein-sparing action with Cr-Pic supplementation. Significantly (P < 0.05) higher serum insulin and liver glycogen in 800 μg Cr-Pic kg^-1 diet fed fishes denote an improvement in carbohydrate metabolism. However, significantly (P < 0.05) higher ATPase and SOD activities were also observed when chromium supplementation was more than 800 μg kg^-1 diet, indicating stress at higher level. The present study indicates that growth and carbohydrate utilization can significantly (P < 0.05) be improved by feeding the L. rohita fingerlings with Cr-Pic (800 μg kg^-1 diet) supplemented diet in laboratory condition.

Chromium propionate improves performance and carcass traits in broilers

There is evidence to suggest that poultry may have a dietary requirement for metabolically available chromium (Cr) that exceeds the amount provided through wheat soybean meal diets. The objective of the present study was to investigate the effects of dietary supplemental organic Cr from Cr propionate at different dose levels (control = 0 μg/kg, T1 = 200 μg/kg, T2 = 400 μg/kg) on the growth performance, carcass traits, and meat quality of broilers. Weight gain and feed intake of each treatment were recorded at the start and after 14, 28 and 35 d, and feed conversion ratios (FCR) were calculated accordingly. At 35 d of age, birds were randomly selected and euthanized for carcass evaluation. Results of the first trial indicate that both Cr propionate treatments increased final body weight (P < 0.05), feed efficiency (P < 0.05) and body weight gain (P < 0.0001). Furthermore, Cr propionate supplementation improved (P < 0.0001) all carcass characteristics. Interestingly, with increased Cr dosage, carcass yield, dressing percentage and breast meat yield increased linearly (P < 0.0001). The second study reveals that the feed intake in the control group was significantly higher compared to both Cr propionate supplemented groups (T1 & T2). Furthermore, the Cr propionate supplemented T2 group displayed a significantly lower FCR than the control and T1 group (P = 0.027). Finally, Cr propionate supplementation increased the dressing percentage compared to control birds (P < 0.0001). In the third experiment, Cr propionate supplementation (T1 & T2) increased final body weight and decreased FCR compared with the control treatment. These effects were highly significant (P < 0.0001) throughout all feeding phases of the trial. Cr propionate supplementation also increased (P < 0.0001) carcass yield, dressing percentage, breast meat yield, leg and thigh weights compared with the control treatment. In conclusion, growth performance, feed conversion, carcass yield, breast and leg meats of broiler birds can be significantly improved by dietary inclusion of Cr propionate. Cr propionate can be supplemented to broiler birds from 1 d old of age at a level that provides 200 or 400 μg/kg organic Cr and can increase the efficiency of broiler production.

Green Synthesis of Chromium Nanoparticles and Their Effects on the Growth of the Prawn Macrobrachium rosenbergii Post-larvae

This study deals with synthesis of chromium nanoparticles (CrNPs) from potassium dichromate using the aqueous extract of Allium sativum. They were characterized through UV-VIS light, FE-SEM, EDX, XRD, and FT-IR, which revealed uniform, mono-dispersive, and highly stable CrNPs of 31-64-nm size. The Artemia nauplii was enriched with 4.94 mg/L of CrNPs (24-h LC₅₀) at different durations (½, 1, 2, and 4 h) and then fed to Macrobrachium rosenbegii post-larvae (PL) for 30 days as live feed. The results showed that ½- and 1-h enriched Artemia nauplii led to significant improvements in nutritional indices including growth and survival, and concentrations of tissue biochemical constituents, such as total protein, amino acid, carbohydrate, and lipid of M. rosenbergii PL (P < 0.05), which suggests that this concentration of CrNPs was non-toxic to M. rosenbergii PL. This was confirmed by the insignificant alterations recorded in activities of SOD and CAT (P > 0.05) in M. rosenbergii PL fed with ½- and 1-h enriched Artemia nauplii as live feed. After that, SOD and CAT activities started to increase. Therefore, this optimized concentration of CrNPs (4.94 mg/L) is recommended for enrichment of Artemia nauplii for ½-1-h duration as a sustainable material in the nursery of M. rosenbergii.

Effects of chromium picolinate supplementation on growth, body composition, and biochemical parameters in Nile tilapia Oreochromis niloticus

A feeding trial was conducted to evaluate the effects of chromium picolinate (Cr-Pic) on growth performance, body composition, and biochemical parameters in Nile tilapia Oreochromis niloticus. Five experimental diets were formulated with high-protein diet (HP), low-protein diet (LP), and LP + 0.6, 1.2, or 1.8 mg kg^-1 Cr, respectively. Each diet was randomly assigned to four replicate groups of 30 fish per aquarium in a water-circulated rearing system for 60 days. Dietary 1.2 or 1.8 mg kg^-1 Cr inclusion significantly affects the final body weight, weight gain rate, specific growth rate, feed efficiency rate, and protein efficiency ratio of tilapia compare to the LP diet. The Cr inclusion significantly decreased the content of blood urea nitrogen and the blood glucose level generally with increasing Cr inclusion levels. The Cr content of gill tissue was higher than that of back muscle in all treatments, and the addition of 1.2 or 1.8 mg kg^-1 Cr significantly enhanced the Cr contents of back muscle. The cold stress test results showed that adding Cr significantly enhanced the serum T3 concentration and reduced the activity of serum creatine kinase and the serum cortisol level. These results indicated that the supplementation of chromium picolinate can improve the growth performance and reshape the serum protein and carbohydrate metabolism profile and has the potentiality to alleviate the detrimental effects of cold stress in Nile tilapia. The low-protein diet with 1.8 mg kg^-1 Cr obtained the same growth performance as the high-protein diet.

Effect of supplemental levels of chromium picolinate on the growth performance, serum traits, carcass characteristics and lipid metabolism of growing-finishing pigs

This study investigated the effect of chromium picolinate supplementation on growth performance, carcass characteristics and lipid metabolism of growing-finishing pigs. Sixty Landrace ✕ Yorkshire ✕ Duroc (LYD) pigs with a mean initial body weight of 46·65 (s.e. 6·72) kg were randomly allocated into three groups with two replicates. They were supplemented with 0 , 200, or 400 μg/kg (ppb) chromium in the organic form of chromium picolinate for 90 days. Supplementation with chromium picolinate in the pigs’ ration improved their growth performance, enhanced average daily gain (P < 0·05), and increased their food consumption, especially in the 200 ppb group ( P > 0·05). Chromium picolinate supplementation also improved carcass characteristics, as the average back fat thickness was reduced and the loin-eye area was enhanced ( P < 0·05). The serum chromium concentration in the chromium picolinate supplemented groups was approximately twice that of the controls ( P < 0·05). Supplementation with chromium also markedly reduced serum total cholesterol, triacylglycerol (TG) and urea concentrations in the pig serum ( P < 0·05). Serum insulin was significantly decreased in the 400 ppb group, while serum glucose was decreased in the 200 ppb group ( P < 0·05). Very low density lipoprotein (VLDL) was reduced and low density lipoprotein (LDL) was increased in the chromium supplementation group. Meanwhile, the high density lipoprotein-cholesterol and VLDL-cholesterol were markedly increased, while LDL-cholesterol was significantly diminished ( P < 0·05) in the 200 ppb group. The adipocyte diameter and volume in the chromium-supplemented groups tended to be larger than in the control ( P = 0·07). In vitro studies indicated that incorporation of [u, 14C]glucose into total lipids (P < 0·05) was increased by chromium supplementation. However, there were no lipolysis differences among the groups (P > 0·05). The carcasses of the pigs that received the chromium supplemented ration contained less oleic acid (C18 : 1) and total unsaturated fatty acids (P < 0·05). On the other hand, the total saturated fatty acid content was higher than that of the controls (P < 0·05). Results in this study demonstrate that chromium picolinate supplementation in pigs has several beneficial effects.

Chromium propionate in broilers: effect on insulin sensitivity

The objective of this study was to evaluate the effects of dietary chromium (Cr), as chromium propionate, on measures of insulin sensitivity. Liver and muscle glycogen, and plasma glucose and non-esterified fatty acid (NEFA) concentrations were used as indicators of insulin sensitivity. In total, 288 newly hatched male Ross broilers were divided into 4 dietary treatments consisting of 0 (control diet analyzed 0.43 to 0.45 mg Cr/kg), 0.2, 0.4, or 0.6 mg supplemental Cr/kg diet, resulting in 4 treatments with 9 replicate pens per treatment containing eight birds per pen. At d 21, 2 birds per cage were removed based on the greatest deviation from pen mean BW, resulting in each pen containing 6 birds for the final analyses. Final BW were taken on d 40, and on d 42 two birds from each pen were sampled for plasma NEFA, glucose, and muscle and liver glycogen determination at the initiation and termination of a 22 h fast. The remaining 2 fasted birds were sampled after a 30 min refeeding period. No differences were observed in feed intake, BW gain, or feed efficiency on d 21 or d 40. Liver glycogen tended (P=0.10) to be greater in Cr-supplemented chicks in the fed state, and muscle glycogen concentrations tended (P=0.07) to be greater in Cr-supplemented chicks compared with controls following fasting and refeeding. Plasma glucose concentrations were not affected by dietary Cr in the fed, fasted, or refed state. Plasma NEFA levels were not affected by treatment in fed or fasted birds. However, plasma NEFA concentrations were lower (P<0.01) in chicks supplemented with Cr than in controls following fasting and refeeding, suggesting that Cr increased insulin sensitivity. No differences were detected among birds supplemented with 0.2 or 0.4 mg Cr/kg, and among those receiving 0.4 or 0.6 mg Cr/kg. Results of this study indicate that Cr propionate supplementation of a control diet containing 0.43 to 0.45 mg Cr/kg enhanced insulin sensitivity.

Dietary chromium picolinate of varying particle size improves carcass characteristics and insulin sensitivity in finishing pigs fed low- and high-fat diets

The aim of the present study was to evaluate the effect of the different-sized particles of chromium (Cr) picolinate (CrPic) and dietary fat on growth performance, carcass traits and insulin sensitivity of finishing pigs. Ninety-six Large White × Landrace gilts were stratified on bodyweight, housed in pens of three pigs and then, on a pen basis, randomly allocated to eight treatment groups in a 2 × 4 factorial design for 6 weeks. The respective factors were dietary fat (2.2% or 5.7%) and dietary CrPic (0 mg/kg, 400 mg/kgnormal-size CrPic, 400 mg/kg 1-μm CrPic (μCrPic), or 400 mg/kg 100-nm CrPic (nCrPic)). Over the first 21 days, average daily gain (ADG) was increased by dietary CrPic (0.94 vs 1.01 kg/day, P = 0.021), although there was no difference (P = 0.17) between the CrPic particle sizes. High dietary fat also increased ADG over this period (0.96 vs 1.03 kg/day, P = 0.013). However, the responses to both dietary CrPic and fat diminished over time and so there was no effect of CrPic (P = 0.35) or fat (P = 0.93) on ADG over the full 42 days. Dietary CrPic increased carcass weight and muscle depth and decreased P2 backfat. Furthermore, dietary Cr decreased plasma insulin (7.66 vs 5.09 mU/L, P = 0.018) and the homeostatic model assessment (1.25 vs 0.82, P = 0.009), indicating an improvement in insulin sensitivity. In conclusion, dietary Cr can increase ADG and improve carcass traits and insulin sensitivity in lean pigs. There were few differences among particle sizes, possibly because the response to dietary CrPic may already be maximised at 400 mg/kg.

Effects of dietary chromium picolinate and peppermint essential oil on growth performance and blood biochemical parameters of broiler chicks reared under heat stress conditions

A study was conducted using 240 female day-old broiler chicks to evaluate the effects of dietary chromium picolinate (CrPic), peppermint essential oil (P.mint), or their combination on growth performance and blood biochemical parameters of female broiler chicks raised under heat stress conditions (HS, 23.9 to 38 °C cycling). Average daily gain (ADG), average daily feed intake (ADFI), and feed conversion ratio (FCR) were obtained from 1 to 42 days of age. Furthermore, at the end of the experiment (day 42), birds were bled to determine some blood biochemical parameters and weighed for final body weight (BW). ADFI, ADG, and BW were not influenced significantly by dietary CrPic and P.mint (P>0.05). A significant interaction between dietary CrPic and P.mint on FCR (P=0.012) was detected. FCR significantly decreased in chicks fed the diet including both CrPic and P.mint compared with the CrPic group. Significant interaction between dietary P.mint and CrPic on serum concentrations of triglycerides, glucose, and albumin were observed (P<0.05), but the other measured blood biochemical parameters were not statistically affected by dietary treatments (P>0.05). The serum concentrations of glucose, triglycerides were decreased (P<0.05) in broilers fed the diet including both CrPic and P.mint. Plasma chromium (Cr) content increased significantly (P<0.05) in birds fed the CrPic-included diet compared with the control group (P<0.05). From the results of the present experiment it can be concluded that dietary supplementation with combined P.mint and CrPic could have beneficial effects on some blood biochemical parameters of female chicks reared under heat stress conditions.

Performance, egg quality traits, and serum metabolite concentrations of laying hens affected by dietary supplemental chromium picolinate and vitamin C under a heat-stress condition

A 3 × 2 factorial experiment consisting three levels (0, 200, and 400 μg/kg) of chromium (chromium picolinate) and two levels (0 and 250 mg/kg) of vitamin C was employed to evaluate the effects of these dietary supplements on performance, egg quality traits, and serum biochemical parameters of heat-stressed laying hens (Lohmann LSL-Lite) from 66 to 74 weeks of age. Feed intake increased when birds were given either 400 μg/kg chromium or 250 mg/kg vitamin C (P < 0.05), but the birds that received both chromium and vitamin C consumed feed similar to those that received only chromium. Dietary treatments had no effect on egg production, egg mass, egg volume, feed conversion ratio, and body mass (P > 0.05). The birds that fed on diet with chromium or vitamin C produced eggs with higher shell mass and thickness compared to the control. Both eggshell mass and thickness decreased when vitamin C and chromium were supplemented simultaneously, and birds given the diet supplemented with 400 μg/kg chromium and 250 mg/kg vitamin C had eggshell mass and thickness similar to those of the control group. The serum concentration of chromium increased due to increasing level of dietary chromium (P < 0.05). The birds that received diet with chromium and vitamin C had higher serum concentrations of chromium compared to those that received only chromium (P < 0.05). Similarly, the hens that received chromium and vitamin C had higher serum concentrations of calcium and phosphorus compared to the hens fed with other treatments (P < 0.05). The birds given with supplemental chromium exhibited lower serum glucose, total cholesterol, and triglycerides concentrations but higher serum albumin and total protein concentrations compared to the other groups (P < 0.05).

Chromium supplementation can alleviate the negative effects of heat stress on growth performance, carcass traits, and meat lipid oxidation of broiler chicks without any adverse impacts on blood constituents

This study was conducted to determine the effects of dietary supplementation with Cr nicotinate and Cr chloride and their optimum inclusion rate on performance, carcass traits, meat oxidative stability, serum metabolites, hematological parameters, and liver chromium concentration in heat-stressed broilers. A total number of 420, 1-day-old male broiler chicks were randomly assigned to seven treatments with four replicates of 15 chicks. The dietary treatments consisted of the basal diet supplemented with 0 (control), 500, 1,000, and 1,500 μg/kg Cr in the form of Cr nicotinate and Cr chloride. Chicks were raised for 6 weeks in heat stress condition (33 ± 2°C). Supplements of organic and inorganic Cr particularly at 1,500 μg/kg incorporation increased feed consumption (P < 0.05) and body mass gain of broilers (P < 0.01). Cr supplementation increased carcass yield and decreased abdominal fat (P < 0.01). Supplementation of 1,500 μg/kg Cr nicotinate (P < 0.05) enhanced liver Cr concentration. Storage time increased lipid oxidation of meat (P < 0.01). Cr decreased lipid oxidation of breast and thigh muscles over 2 (P < 0.01) or 6 (P < 0.05) days of storage time. Birds fed 1,500 μg/kg Cr nicotinate, had lower concentration of serum glucose and triglyceride at 21 days (P < 0.05). Hematological parameters tested at 21 and 42 days, were not influenced. The results suggested that dietary Cr supplementation regardless of its source have a positive effect on productive, and carcass traits, also enhances oxidative stability of refrigerated meat in broilers reared under heat stress conditions.

The effect of different levels of organic and inorganic chromium supplementation on production performance, carcass traits and some blood parameters of broiler chicken under heat stress condition

A total of 250 broilers in a completely randomized design selected to evaluate the effect of different levels of chromium (Cr) supplementation on performance, carcass traits and some blood parameters of heat-stressed broiler chicks. All birds were kept under heat stress temperature (33 ± 3°C) and divided into five treatments groups. Each treatment consisted of five pens with 10 birds in each pen. The basal diets were supplemented with 0 ppb (control), 800 ppb Cr-L-Met (T(1)), 1,200 ppb Cr-L-Met (T(2)) or 800 ppb CrCl(3) (T(3)), and 1,200 ppb CrCl(3) (T(4)). The feed intake and body mass were measured at 10, 21, and 42 days of age. Blood samples were collected from two birds in each replicates to determine biological and hematological values at 28 and 42 days of age. There were no significant difference in mass gain and feed conversion of broilers that received Cr supplementations compared with controls. The serum glucose concentration decreased in broilers received organic chromium methionine supplements compared with other treatments groups. Slight but not significant increases were observed in serum high-density lipoprotein (HDL) concentration of treated groups than controls while the mean serum HDL concentration was significantly higher in T(2) group compared with control group. Serum low-density lipoprotein level decreased in broiler received organic Cr supplements (p < 0.05).

Effect of different protein and limiting amino acid levels coupled with a supplement of chromium picolinate on lipid metabolism and carcass characteristics of pigs

This study investigated the response of different dietary protein and limiting amino acid concentrations coupled with a supplement of chromium in growing-finishing pigs. Sixty Landrace × Yorkshire × Duroc bacon type pigs with an initial live weight of 33·08 (s.d. 4·80) kg were randomly assigned into six groups with an equal number of males and females. They were given diets containing proportionately 1·0, 1·1 or 1·2 of the National Research Council recommendation of crude protein and limiting amino acid (lysine and methionine) levels and coupled with supplementing chromium at 0 or 200 ng/kg in the form of chromium picolinate (Crpic). The experiment was completed when the pigs' live weight reached 120 kg. Experiment results indicated that different nutrient levels or Crpic supplement did not significantly affect pig growth (P > 0·05). However, both nutrient levels and Crpic supplementation increased y-globulin concentration (P < 0·05). In addition, Crpic supplement not only significantly reduced the backfat thickness, serum insulin level and VLDL-C + LDL-C concentration (P < 0·05) but also increased the loin-eye area and HDL-C concentration of pigs (P < 0·05). On the other hand, the particle sizes of HDL and VLDL were decreased and increased (P < 0·05), respectively. In addition, Crpic supplement increased the activities of adipose tissue lipogenesis related enzymes such as fatty acid synthetase, ATP-citrate cleavage enzyme and NADP-malic dehydrogenase (P < 0·05 to 0·001). In a similar manner, Crpic supplement increased the activities of adipose tissue lipoprotein lipase and serum lecithin-cholesterol acyltransferase (P < 0·05). However, the interactions of nutrient levels × Crpic supplementation were insignificant (P > 0·05). Results in this study demonstrated that chromium picolinate supplement created a beneficial effect but supplements of chromium coupled with high dietary protein and limiting amino acid levels were unnecessary for bacon-type pigs.

Effect of dietary chromium picolinate on growth performance and blood parameters in grass carp fingerling, Ctenopharyngodon idellus

An experiment was conducted to investigate the effect of dietary chromium picolinate supplement on growth and haematology parameters of grass carp, Ctenopharyngodon idellus. Six diets with increasing dietary chromium picolinate levels 0, 0.2, 0.4, 0.8, 1.6 and 3.2 mg kg(-1) were fed to triplicate groups of 20 fish (initial weight of 12.78 +/- 1.16 g, mean +/- SD) in a flow water system for 10 weeks. Fish fed the diet supplemented with 0.8 mg Cr kg(-1) had significantly improved weight gain (WG), feed efficiency ratio (FER), protein efficiency ratio (PER) and protein retention (PR). Fish fed high-chromium diets exhibited lower whole-body crude lipid contents than fish fed low-chromium diets. Liver glycogen concentrations for fish fed the diet with 0.2 mg Cr kg(-1) was the highest (77.67 mg g(-1)). Fish fed the diet supplemented with 1.6 and 3.2 mg Cr kg(-1) had significantly lower liver glycogen concentrations than other groups (P < 0.05). The highest serum insulin concentrations were observed in fish fed the diet supplemented with 0.8 mg Cr kg(-1), but serum insulin concentrations decreased (P < 0.05) when dietary supplementation of chromium was higher than 0.8 mg Cr kg(-1). Cholesterol concentrations decreased in direct proportion to dietary chromium level and achieved the lowest level when the fish were fed the 0.8 mg Cr kg(-1) diet, but increased when the fish were fed the diet with more than 0.8 mg Cr kg(-1) (P < 0.05). Fish fed the diet supplemented with 0.8 mg Cr kg(-1) had higher triglyceride and high-density lipoprotein cholesterol (HDL-C) concentrations compared to other treatments. The results of the present study suggested that chromium picolinate could modify serum carbohydrate and lipid metabolism profile, and that the optimal dietary chromium level was 0.8 mg kg(-1) for grass carp according to growth.

Níveis de cromo orgânico em rações para frangos de corte mantidos sob estresse por calor no período de um a 42 dias de idade

Avaliou-se o efeito da suplementação de cromo sobre o desempenho e o rendimento de cortes de frangos, mantidos em ambiente de alta temperatura, no período de um a 42 dias de idade. Foram utilizados 400 frangos de corte, machos, da linhagem Cobb, em um delineamento experimental inteiramente ao acaso, com cinco tratamentos, 0, 350, 700, 1.050 e 1.400ppb de cromo na ração, oito repetições e 10 aves por repetição. Nos períodos de um a 21 e de um a 42 dias de idade, não houve influência dos tratamentos sobre o ganho de peso, o consumo de ração e a conversão alimentar das aves, mas observou-se que o consumo de cromo aumentou de forma linear. Os tratamentos não influenciaram os pesos absoluto e relativo de nenhum dos cortes, peito, coxa e sobrecoxa, avaliados aos 42 dias de idade. A suplementação de até 1.400ppb de cromo na ração não influenciou o desempenho e o rendimento de cortes nobres de frangos de corte mantidos em estresse por calor, no período de um a 42 dias de idade.

Effects of chromium propionate on growth, carcass traits, and pork quality of growing-finishing pigs1,2

An experiment was conducted to determine the effect of dietary Cr propionate (CrProp) on growth, carcass traits, and pork quality of crossbred finishing gilts. Dietary treatments were 0 or 200 ppb Cr (as CrProp; as-fed basis), and each treatment was replicated four times with five gilts per replicate pen. Gilts were fed diets containing 0.82% lysine from 73 to 80 kg BW and 0.64% lysine from 80 to 115 kg BW. At the end of the trial, carcass and pork quality data were collected from four gilts per replicate. Average daily gain, ADFI, and G:F were not affected (P = 0.76 to 0.96) by CrProp. Before delivery at the abattoir, shrink loss was determined after an 18-h fast (fasting shrink) and after hauling (shipping shrink) pigs for 2.66 h (209.2 km). Fasting, shipping, and overall shrink were not affected (P = 0.14 to 0.39) by CrProp. Carcass length was increased (P = 0.03) in pigs fed CrProp. Loin muscle area, 10th-rib backfat thickness, average backfat thickness, dressing percent, muscle score, fat-free lean, and percent lean were not affected (P = 0.18 to 0.95) by CrProp. Twenty-four-hour loin pH was increased (P = 0.10) in pigs fed CrProp, but 45-min loin and ham pH and 24-h ham pH were not affected (P = 0.39 to 0.83) by CrProp. Subjective (color, marbling, firmness, and wetness) and objective (Commission Internationale de l'Eclairage L*, a*, b*) assessments of the loin muscle (at the 10th-rib interface) were not affected (P = 0.62 to 0.99) by CrProp. Forty-eight-hour drip (P = 0.10) and 21-d purge loss (P = 0.01) were decreased in pigs fed CrProp, but cook and total loss (drip + cook loss) and shear force were not affected (P = 0.35 to 0.53) by CrProp. Plasma cortisol, glucose, and lactate concentrations were not affected (P = 0.28 to 0.97) by CrProp after transportation or during exsanguination. These data indicate that CrProp may improve some aspects of pork quality (loin pH, drip and purge loss) but not growth performance or carcass traits.

Chromium supplementation can alleviate negative effects of heat stress on egg production, egg quality and some serum metabolites of laying Japanese quail

This study was conducted to determine the effects of Cr (chromium picolinate, CrPic) supplementation at various levels (0, 200, 400, 800 or 1200 microg/kg of diet) on egg production, egg quality and serum concentrations of insulin, corticosterone and glucose in laying Japanese quail (Coturnix coturnix japanica) reared under conditions of heat stress (32.5 degrees C). Laying Japanese quail (n = 150; 45 d old) were divided into five groups of 30 birds. The quail were fed either a control diet containing 965 microg Cr/kg diet or the control diet supplemented with 200, 400, 800 or 1200 microg of Cr/kg diet. Increased supplemental chromium increased body weight (P = 0.05, linear), feed intake (P = 0.05, linear), egg production (P = 0.01, linear) and also improved feed efficiency (P = 0.01, linear). Increased supplemental chromium linearly increased egg weight (P = 0.01), eggshell thickness, egg specific gravity (P = 0.05) and Haugh unit (P = 0.01). Serum insulin concentration increased linearly (P = 0.01), whereas corticosterone and glucose concentration decreased linearly (P = 0.05) as dietary chromium increased. The best results were obtained with 1200 microg Cr/kg diet, and chromium supplementation at such a level can be considered to be protective management practice in a quail diet, reducing the negative effects of heat stress.

Effects of chromium nicotinate on performance, carcase characteristics and blood chemistry of growing turkeys

1. The objective of this trial was to study the effects of chromium nicotinate (Cr) supplementation on the performance, carcase characteristics and blood constituents of 9 to 22 week-old male turkeys. 2. Fifty-four 8-week-old male turkeys weighing 2.9 +/- 0.28 kg were allocated at random into 9 groups with 3 dietary treatments and 3 replicates. The dietary treatment was different dietary concentrations of chromium in the basal diet, to provide 0 (control), 1 or 3 mg/kg. The feeding trial lasted for 14 weeks. 3. Results showed that 1 mg/kg chromium supplementation significantly improved weight gain and food intake at 9 to 18 weeks of age but did not significantly influence performance at 19 to 22 week of age. The breast and thigh muscle were significantly increased in birds receiving 1 mg/kg chromium supplementation but were decreased by 3 mg/kg of supplementation. 4. Dietary chromium supplementation did not significantly influence other serum constituents, including insulin, HDL, VLDL+LDL, HDL-C, VLDL-C+LDL-C, total protein, albumin, and gamma-globulin at 18 and 22 weeks of age. 5. The serum triacylglycerol (TG) and uric acid contents were significantly increased, while glycerol and alpha-globulin were significantly reduced by 3 mg/kg chromium supplementation. However, 1 mg/kg chromium supplementation significantly reduced serum cholesterol and glycerol at 18-weeks old. At 22 weeks of age, 1 mg/kg chromium supplementation significantly increased serum glucose and decreased the uric acid concentration whereas 3 mg/kg chromium supplementation significantly increased the creatinine concentration and decreased beta-globulin concentration.

Performance, serum characteristics, carcase traits and lipid metabolism of broilers as affected by supplement of chromium picolinate

1. This study investigated the effects of dietary supplementation with chromium picolinate on the performance, serum and carcase traits and lipid metabolism of broilers. In trial 1, 120 1-day-old broilers with an equal number of males and females were assigned at random to 4 groups with 3 replicates. Four treatments with dietary supplements of 0 (control), 800, 1600 and 3200 microg/kg of chromium picolinate were used. In trial 2, 6-week-old broilers (20) were used to determine how supplements of 0, 200, 400 and 800 microg/kg chromium in an incubation medium influence their hepatocyte lipogenic capacity and adipocyte lipolysis, in vitro. 2. Dietary supplements of 1600 and 3200 microg/kg chromium in broiler diets significantly increased food consumption (P<0.05); 1600 microg/kg markedly improved weight gain (P<0.05); 1600 and 3200 microg/kg groups showed increased liver lipid content (P<0.05). However, the abdominal fat content tended to decrease in these 2 groups. 3. Dietary supplements of 1600 and 3200 microg/kg of chromium decreased serum glucose and nonesterified fatty acids (NEFA) concentrations while increasing serum phospholipid content (P<0.05). Insulin concentration decreased only in birds receiving 3200 ppb chromium (P<0.05). Serum triacylglycerol (TG) clearance rate in chromium-supplemented groups was markedly enhanced (P<0.05). 4. In addition, chromium supplemented groups had increased serum HDL contents and also reduced serum VLDL and LDL contents (P<0.05). 5. Trial 2 indicated that lipogenesis from [U-14C]glucose by isolated hepatocytes was significantly enhanced by 400 ppb chromium (P<0.05). 6. The results from this study demonstrate that a supplement of 1600 microg/kg of chromium picolinate in the ration influences the growth, carcase, serum traits and lipid metabolism of broilers.

Immune-endocrine interactions in agricultural species: chromium and its effect on health and performance

The purported performance-enhancing effects of supplemental Cr, as elaborated in studies focusing on beef and dairy cattle models of agricultural stress, affect both immune and endocrine pathways. Furthermore, interactions between the immune and endocrine systems, associated with the actions of insulin and cortisol, may be coordinated through the production of regulatory cytokines. Unlocking the mechanism of action of Cr as a useful farm animal management tool may provide further understanding of the health and performance ramifications of immune-endocrine interactions in agricultural species.

Mechanisms of chromium carcinogenicity and toxicity

Chromium, like many transition metal elements, is essential to life at low concentrations yet toxic to many systems at higher concentrations. In addition to the overt symptoms of acute chromium toxicity, delayed manifestations of chromium exposure become apparent by subsequent increases in the incidence of various human cancers. Chromium is widely used in numerous industrial processes, and as a result is a contaminant of many environmental systems. Chromium, in its myriad chemical forms and oxidation states, has been well studied in terms of its general chemistry and its interactions with biological molecules. However, the precise mechanisms by which chromium is both an essential metal and a carcinogen are not yet fully clear. The following review does not seek to embellish upon the proposed mechanisms of the toxic and carcinogenic actions of chromium, but rather provides a comprehensive review of these theories. The chemical nature of chromium compounds and how these properties impact upon the interactions of chromium with cellular and genetic targets, including animal and human hosts, are discussed.

High dietary niacinamide and performance of male poults at 16 weeks of age

1. Male poults were fed diets with 50 and 100 mg supplemental niacinamide/kg and grown at stocking densities of 3.2 and 4.3 birds/m2 from 56 to 112 d. 2. At 50 mg/kg niacinamide high stocking density (HSD) depressed 112 d body weight and gain from 56-112d. High dietary niacinamide (100 mg/kg alleviated the growth depression under HSD but decreased body weight gain under low stocking density (LSD). 3. Dressed yield and hock width were not affected by dietary niacinamide or stocking density. 4. Dressed carcase composition was altered by stocking density. The dressed carcase of HSD birds contained 3.7% more protein and 7% less fat. 5. High dietary niacinamide tended to increase carcase protein (+2.4%) and decrease carcase fat (-4.0%).

Response of male poults to high levels of dietary niacinamide

The response was determined of male poults to high levels of dietary niacinamide, when maintained in a stressful environment of high stocking density and high litter moisture induced by excess dietary NaCl. The experiment was designed as a factorial (2 by 2 by 2) with 70 versus 140 mg of niacinamide per kg; .3 versus 1% NaCl; 7 versus 14 birds per m2. Each treatment was assigned to 6 pens, with either 20 or 40 males per pen depending on stocking density. The calculated niacin content of the basal diet was 22 mg per kg; the experimental diets contained 92 and 162 mg of total niacin per kg. Added niacinamide at 140 mg per kg increased the body weight at 8 wk of age (3,095 versus 3,198) at .3% dietary NaCl. The response to 140 mg per kg of niacinamide was 4.6% at .3% NaCl and only 1.9% at 1% NaCl. The high level of niacinamide was ineffective in terms of alleviating the growth depression induced by a high stocking density. Treatment effects were not detected in relation to feed efficiency. The incidence of leg abnormalities was not influenced by dietary niacinamide or by litter moisture, but was aggravated by a high stocking density. The treatments did not induce ascites or macroscopic lesions in the heart or kidney. These findings demonstrated that supplemental niacinamide at 140 mg per kg, in a basal diet calculated to contain 22 mg of niacin per kg of feed, will produce a significant increase in the weight gain of male poults at 8 wk of age under praxis conditions when dietary salt is at .3%, but not at 1%.

Chromium and vanadium effects on glucose metabolism and lipid synthesis in the chick

The effects of 20 ppm chromium (CrCl3.6H2O) and/or 20 ppm vanadium (NaVO3.nH2O) on growth, glucose metabolism, and lipid synthesis in chicks were studied in a 2 X 2 factorial experiment. Chicks were fed experimental diets from day-old to 3 weeks of age. At 3 weeks, four chicks per treatment were injected intraperitoneally (i.p.) with 250 mu Ci 3H2O and 4 mu Ci [U-14C]glucose. Chicks were bled by cardiac puncture and killed 30 min postinjection. Dietary vanadium reduced body and liver weights and liver cholesterol while serum cholesterol was increased. Chromium had no effect on these parameters and there was no significant interaction of chromium with vanadium. Chromium and vanadium each increased 14C incorporation into liver fatty acids over that of controls. However, the combination of chromium and vanadium was without effect so that the interaction was significant. Incorporation of 3H from H2O into liver fatty acids paralleled that of 14C from glucose for all treatments. In vitro studies on the uptake and oxidation of glucose by liver slices from chicks fed the basal diet were conducted. Chromium increased the rate of glucose utilization 16% over control and vanadium increased the rate by 33%. The combination of chromium and vanadium was no different from vanadium alone. A chromium vanadium antagonism was observed in some metabolic processes but not on body or organ weight.

Clinical and biochemical aspects of chromium deficiency

The essentiality of chromium (Cr) in animal and human nutrition is now well accepted. In animals, Cr deficiency can cause a diabetic-like state, impaired growth, elevated blood lipids, increased aortic plaque formation, and decreased fertility and longevity. The ability of Cr to potentiate insulin sensitivity has considerable experimental support. In the human, Cr deficiency has been demonstrated unequivocally in only one clinical situation, patients on total parenteral nutrition without added Cr. In such patients, impaired glucose tolerance, hyperglycemia, relative insulin resistance, peripheral neuropathy, and a metabolic encephalopathy have been noted with reversal of the clinical phenomena by Cr repletion. Many studies have been performed to determine whether Cr deficiency may be important in other clinical conditions, namely, diabetes mellitus, pregnant and parous women, and the aged population. Available data indicate that Cr supplementation can improve glucose metabolism in glucose intolerant individuals and decrease the total/HDL cholesterol ratio regardless of the status of glucose tolerance. However, whether Cr supplementation has long-term health benefits is unknown. Further, despite many tantalizing observations, it is still unclear whether Cr deficiency, latent or overt, is common in any human situation other than generalized malnutrition and total parenteral nutrition without added Cr. Technical uncertainties in the analysis of Cr, Cr contamination of food by the use of stainless steel processing equipment and eating utensils, and the lack of a clinically feasible test for Cr deficiency continue to impede progress in Cr research. Nevertheless, there is considerably more clarity as to plasma and urine Cr levels, food and tissue Cr content, and metabolic pathways of Cr metabolism than existed a decade ago. It is expected that progress will accelerate, since critical questions can now be addressed regarding the role of Cr in human nutrition.