Relative bioavailability of manganese proteinate for broilers fed a conventional corn-soybean meal diet

Effect of manganese amino acid complexes on growth performance, meat quality, breast muscle and bone development in broilers

1. This study was conducted to investigate the effects of dietary supplementation of manganese (Mn) amino acid complexes on growth performance, Mn deposition, meat quality, breast muscle and bone development of broilers.2. A total of 504, one-day-old male Arbor Acres broilers were randomly divided into seven treatments; control diet (CON; basal diet, no extra Mn addition), manganese diet (MnN as Numine®-Mn; CON + 40, 80, 120 or 160 mg Mn/kg), manganese-S group (MnS; CON + 120 mg Mn/kg as MnSO4·H2O), manganese-A diet (MnA as Mn from hydrolysed feather meal; CON + 40 mg Mn/kg as MnA).3. There were no significant differences for average daily gain (ADG) or feed intake (ADFI) among diets during the feed phases (p > 0.05). The FCR in the starter and over the whole period were quadratically affected by dietary MnN dosage and gave the lowest FCR at 80 mg/kg (p < 0.05). The Mn content of thigh muscle, jejunum, heart, pancreas, liver and tibia increased linearly with MnN addition (p < 0.05).4. For meat quality, MnN significantly increased colour (a*), pH45 min and pH24 h, reduced shear force, drip loss and pressure loss of breast muscle (p < 0.05).5. Moreover, MnN significantly upregulated MYOD expression at d 21 and SOD expression at d 42, decreased MuRF1 and Atrogin-1 mRNA level at d 42 in breast muscle. Transcriptome analysis revealed that the regulating effect of MnN on muscle development significantly enriched signalling pathways such as adhesion, ECM-receptor, MAPK, mTOR and AMPK. Furthermore, dietary MnN significantly affected tibia length and growth plate development (p < 0.05) and promoted growth plate chondrocytes by increasing SOX-9, Runx-2, Mef2c, TGF-β, Ihh, Bcl-2 and Beclin1 and decreasing Bax and Caspase-3 (p < 0.05) expression which affect longitudinal tibial development.6. In conclusion, Mn amino acid complexes could improve growth performance, tissue Mn deposition, breast muscle development, meat quality and bone development.

The chemical characteristics of different sodium iron ethylenediaminetetraacetate sources and their relative bioavailabilities for broilers fed with a conventional corn-soybean meal diet

BACKGROUND

Our previous studies demonstrated that divalent organic iron (Fe) proteinate sources with higher complexation or chelation strengths as expressed by the greater quotient of formation (Qf) values displayed higher Fe bioavailabilities for broilers. Sodium iron ethylenediaminetetraacetate (NaFeEDTA) is a trivalent organic Fe source with the strongest chelating ligand EDTA. However, the bioavailability of Fe when administered as NaFeEDTA in broilers and other agricultural animals remains untested. Herein, the chemical characteristics of 12 NaFeEDTA products were determined. Of these, one feed grade NaFeEDTA (Qf = 2.07 × 108), one food grade NaFeEDTA (Qf = 3.31 × 108), and one Fe proteinate with an extremely strong chelation strength (Fe-Prot ES, Qf value = 8,590) were selected. Their bioavailabilities relative to Fe sulfate (FeSO4·7H2O) for broilers fed with a conventional corn-soybean meal diet were evaluated during d 1 to 21 by investigating the effects of the above Fe sources and added Fe levels on the growth performance, hematological indices, Fe contents, activities and gene expressions of Fe-containing enzymes in various tissues of broilers.

RESULTS

NaFeEDTA sources varied greatly in their chemical characteristics. Plasma Fe concentration (PI), transferrin saturation (TS), liver Fe content, succinate dehydrogenase (SDH) activities in liver, heart, and kidney, catalase (CAT) activity in liver, and SDH mRNA expressions in liver and kidney increased linearly (P < 0.05) with increasing levels of Fe supplementation. However, differences among Fe sources were detected (P < 0.05) only for PI, liver Fe content, CAT activity in liver, SDH activities in heart and kidney, and SDH mRNA expressions in liver and kidney. Based on slope ratios from multiple linear regressions of the above indices on daily dietary analyzed Fe intake, the average bioavailabilities of Fe-Prot ES, feed grade NaFeEDTA, and food grade NaFeEDTA relative to the inorganic FeSO4·7H2O (100%) for broilers were 139%, 155%, and 166%, respectively.

CONCLUSIONS

The bioavailabilities of organic Fe sources relative to FeSO4·7H2O were closely related to their Qf values, and NaFeEDTA sources with higher Qf values showed higher Fe bioavailabilities for broilers fed with a conventional corn-soybean meal diet.

Effects of Inorganic and Organic Manganese Supplementation on Growth Performance, Tibia Development, and Oxidative Stress in Broiler Chickens

Manganese (Mn) is an essential trace element for broiler chickens; its deficiency causes tibial dyschondroplasia (TD) characterized by lameness and growth retardation. Inorganic and organic manganese sources are used in global poultry production, but there is a lack of systematic investigations to compare the bioavailability among them. In this study, 120 1-day-old Arbor Acres (AA) broilers were randomly divided into four groups (n = 30), i.e., control group (Mn sulfate, 60 mg/kg), Mn-D group (Mn deficiency, 22 mg/kg), Mn-Gly group (Mn glycinate, 60 mg/kg), and Mn-Pro group (Mn proteinate, 60 mg/kg). During the 42-day experiment, growth performance, tibial bone parameters, pathological index changes, serum biochemical changes, and oxidative stress indicators were evaluated. These results not only suggested that Mn plays a crucial role in the normal development of tibia and the maintenance of redox homeostasis in broilers, but also proved that organic Mn supplementation, especially Mn proteinate, improved the tibia development and the absorption efficiency, as well as overall oxidative stress status of broilers, suggesting that it had greater bioavailability than inorganic Mn. Thus, application of organic Mn source may be an effective way to reduce economic losses and resolve animal welfare concerns due to TD in commercial poultry farming.

Relative Bioavailability of Trace Minerals in Production Animal Nutrition: A Review

The importance of dietary supplementation of animal feeds with trace minerals is irrefutable, with various forms of both organic and inorganic products commercially available. With advances in research techniques, and data obtained from both in-vitro and in-vivo studies in recent years, differences between inorganic and organic trace minerals have become more apparent. Furthermore, differences between specific organic mineral types can now be identified. Adhering to PRISMA guidelines for systematic reviews, we carried out an extensive literature search on previously published studies detailing performance responses to trace minerals, in addition to their corresponding relative bioavailability values. This review covers four of the main trace minerals included in feed: copper, iron, manganese and zinc, and encompasses the different types of organic and inorganic products commercially available. Their impact from environmental, economic, and nutritional perspectives are discussed, along with the biological availability of various mineral forms in production animals. Species-specific sections cover ruminants, poultry, and swine. Extensive relative bioavailability tables cover values for all trace mineral products commercially available, including those not previously reviewed in earlier studies, thereby providing a comprehensive industry reference guide. Additionally, we examine reasons for variance in reported relative bioavailability values, with an emphasis on accounting for data misinterpretation.

Effects of Manganese Hydroxychloride on Growth Performance, Antioxidant Capacity, Tibia Parameters and Manganese Deposition of Broilers

Simple Summary

Manganese is a vital trace element for the growth of broilers. In order to meet the requirement of manganese in broiler production, the additives of manganese sources are usually added into the diet for broilers. Manganese hydroxychloride is a category of hydroxy trace minerals. The present study investigated the effect of dietary supplemental manganese as manganese hydroxychloride for growth performance, antioxidant capacity, tibial quality, and manganese deposition of broilers and recommended that optimal supplementation with manganese as manganese hydroxychloride in diets for broilers was 50–90 mg/kg. This study provides a rational recommendation for the application of manganese hydroxychloride in broiler diets.

Abstract

This study was conducted to investigate the effects of dietary supplementation with manganese hydroxychloride (MHC) on production performance, antioxidant capacity, tibial quality, and manganese (Mn) deposition of broilers. A total of 756 one-day-old male Arbor Acres broilers were randomly allotted to 7 treatments of 6 replicates with 18 broilers per replicate. Broilers were fed corn-soybean meal basal diets supplemented of 100 mg/kg Mn as Mn sulfate (MnSO₄), or 0, 20, 40, 60, 80, 100 mg/kg Mn as MHC for 42 days. The growth performance of broilers was not affected by dietary MnSO₄ or MHC (p > 0.05), whereas the dressing percentage increased linearly (p < 0.05) with increasing of dietary MHC addition level. The activities of catalase (CAT) and manganese superoxide dismutase (MnSOD), and total antioxidant capability (T-AOC) in serum and liver on day 42 increased linearly (p < 0.05) with increasing of dietary MHC level, while malondialdehyde (MDA) concentration reduced linearly (p < 0.05). The length, strength, and density index of tibia increased linearly (p < 0.05) on day 21 as MHC supplementation level increased; there were no differences between MnSO₄ group and 40–100 mg/kg Mn as MHC groups in tibial parameters of broilers (p > 0.05). As supplemental MHC levels increased, the Mn contents in heart, liver, kidney, and tibia increased linearly on day 42 (p < 0.05). In summary, dietary supplementation with MHC improved antioxidant capacity, bone quality, and Mn contents in broilers, but no effects on growth performance were detected. Based on the results of this study, dietary inclusion of 50–90 mg/kg Mn in the form of MHC to broilers is recommended.

Manganese methionine hydroxy analog chelated affects growth performance, trace element deposition and expression of related transporters of broilers

The present study aimed to evaluate the effects of manganese methionine hydroxyl analog chelated (Mn-MHAC) as a manganese (Mn) source on growth performance and trace element deposition in broilers. A total of 432 Arbor Acres commercial female broilers were fed a basal corn-soybean diet containing Mn at 25.64 mg/kg diet for 10 d. They were then randomly assigned to 6 groups, including a control group (the basal diet), a Mn sulfate group (the basal diet supplemented with Mn at 100 mg/kg diet), and 4 Mn-MHAC groups (the basal diet supplemented with Mn-MHAC at 25, 50, 75 and 100 mg Mn/kg diet, respectively). The results showed that compared with the control group, groups supplemented with Mn-MHAC had a positive effect on BW (quadratic, P = 0.017) and ADG (quadratic, P = 0.017). Moreover, the Mn-MHAC (50 mg Mn/kg diet) group had significantly greater BW and ADG (P < 0.05) compared with the other Mn-MHAC groups. Trace element deposition results also showed that tibial Mn increased (linear or quadratic, P = 0.002 and 0.009, respectively) in groups fed diets with increased levels of Mn-MHAC. In contrast, Fe deposition decreased both in the heart (linear, P = 0.020) and tibia (P < 0.05). In addition, the Mn-MHAC supplement noticeably lowered serum Mn-SOD activity (linear or quadratic, P = 0.048 and 0.019, respectively). The relative mRNA levels of divalent metal transporter 1 (DMT1) (P = 0.024), ferroportin 1 (FPN1) (P = 0.049), and Cu transporter-1(CTR1) (P < 0.001) in the duodenum, as well as CTR1 in the jejunum and ileum (P = 0.040 and 0.011, respectively) were higher in the Mn-supplemented group than in the control group. Furthermore, the relative mRNA level of DMT1 in the jejunum and ileum of broilers in the Mn-MHAC group (50 mg Mn/kg diet) did not differ from those in the control group, but was lower than those in the Mn sulfate group (P < 0.05). In conclusion, Mn-MHAC dietary supplementation improved the growth performance and trace element deposition in broilers. From this study, we recommend the optimum Mn-MHAC level to meet the Mn requirement of broilers is 50 to 75 mg Mn/kg diet.

Effect of manganese supplementation on the carcass traits, meat quality, intramuscular fat, and tissue manganese accumulation of Pekin duck

Manganese (Mn) is a trace element present in all tissues and is essential for animal growth and health; it also has an antioxidant capacity in tissues. The effect of Mn on meat quality and the mechanism of fat deposition of the breast muscle is still unclear. Therefore, the present study aimed to investigate the effect of Mn supplementation on the growth performance, meat quality, the activity and transcription of antioxidant enzymes, and fatty acid profile in the breast muscle, and the Mn deposition in tissues of Pekin ducks. A total of 896 one-day-old Pekin ducks were allocated into 7 groups, with 8 replicates, each replicate containing 16 ducks. The treatment diets consisted of basal diet supplemented with manganese sulfate at levels 30, 60, 90, 120, 150, 240 mg/kg (as Mn). Results showed that ducks fed diets supplemented with Mn had no effect on the growth performance but decrease in the feed-to-gain ratio of day 1-14 (P < 0.01). Dietary Mn increased significantly the a∗ (redness) value of the duck breast meat at 24 h and intramuscular fat (P < 0.05), and decreased drip loss and shear force of the breast meat (P < 0.05). Manganese supplement significantly reduced the malondialdehyde content (P < 0.05), and significantly increased the mRNA expressions of manganese superoxide dismutase, thioredoxin 2, peroxiredoxin 3, and catalase (P < 0.05). About the fatty acid profile, dietary Mn increased (P < 0.05) the proportions of the C20 family. Manganese accumulation in the heart, breast muscle, and tibia was increased with Mn supplementation (P < 0.05), and Mn content of the heart conforms to the quadratic curve. Besides, Mn supplementation notably increased mRNA expression in genes involved in lipogenesis and deposition and decreased in genes associated with lipolytic in the breast muscle. These findings reveal that dietary Mn could improve meat quality and enhance antioxidant activity and intramuscular fat, which via regulated gene expression involved in lipogenesis and lipolytic.

Effects of Dietary Iron Concentration on Manganese Utilization in Broilers Fed with Manganese-Lysine Chelate-Supplemented Diet

Dietary iron (Fe) influences manganese (Mn) utilization in chickens fed with inorganic Mn-supplemented diet. This study aimed to determine if dietary Fe levels affect Mn utilization in broilers fed with organic Mn-supplemented diet. Nine hundred 8-day-old broilers were randomly assigned to 1 of 6 treatments in a 3 (Fe level) × 2 (Mn source) factorial arrangement after feeding Mn- and Fe-unsupplemented diets for 7 days. The broilers were fed the basal diets (approximately 28 mg Mn/kg and 60 mg Fe/kg) supplemented with 0, 80, or 160 mg/kg Fe (L-Fe, M-Fe, or H-Fe), and 100 mg/kg Mn from Mn sulfate (MnSO₄) or manganese-lysine chelate (MnLys) for 35 days. The H-Fe diet decreased (P < 0.05) body weight gain and feed intake as compared with L-Fe and M-Fe diets regardless of dietary Mn sources. Dietary Fe levels did not influence (P > 0.10) serum Mn concentration in MnLys-treated broilers, but serum Mn concentration decreased (P < 0.05) with dietary Fe increasing in MnSO₄-treated broilers. The Mn concentration in the duodenum and tibia decreased (P < 0.05) with increasing dietary Fe levels regardless of dietary Mn sources, and MnLys increased (P < 0.04) these indices as compared with MnSO₄. Dietary Fe levels did not significantly influence (P > 0.11) Mn concentration and activity and mRNA abundance of manganese-containing superoxide dismutase (MnSOD) in the heart of MnLys-treaded broilers, but the H-Fe diet decreased (P < 0.05) these indices in MnSO₄-treated broilers as compared with M-Fe and L-Fe diets. The L-Fe diet increased (P < 0.001) duodenal divalent metal transporter 1 mRNA abundance when compared with the M-Fe and H-Fe diets on day 42, regardless of dietary Mn sources. The M-Fe and H-Fe diets decreased (P < 0.001) duodenal ferroportin 1 (FPN1) mRNA level when compared with the L-Fe diet in MnSO₄-treated broilers, while dietary Fe levels did not significantly influence (P > 0.40) duodenal FPN1 mRNA abundance in MnLys-treated broilers. These results indicated dietary Fe levels decreased Mn utilization in MnSO₄-treated broilers, but did not influence Mn utilization in MnLys-treated broilers evaluated by Mn concentrations in the serum and heart, and the activity and mRNA expression of heart MnSOD.

Effects of Dietary Iron on Manganese Utilization in Broilers Fed with Corn-Soybean Meal Diet

To investigate the effects of dietary iron (Fe) levels on manganese (Mn) utilization, 900 8-day-old broilers were randomly assigned to 1 of 6 treatments in a 3 (Fe level) × 2 (Mn level) factorial arrangement after feeding Mn- and Fe-unsupplemented diet for 7 days. The broilers were then fed with basal corn-soybean meal diets (approximately 28 mg Mn/kg and 60 mg Fe/kg) added with 0, 80, or 160 mg/kg Fe (L-Fe, M-Fe, or H-Fe), and 0 or 100 mg/kg Mn for 35 days. Body weight gain was lower for H-Fe broilers than that for L-Fe and M-Fe broilers. On day 42, H-Fe broilers had lower serum Mn concentration as compared with L-Fe and M-Fe broilers, and tibia Mn concentration decreased as dietary Fe increased. In Mn-supplemented broilers, liver Mn was lower in L-Fe and H-Fe treatments than that in M-Fe treatment. H-Fe treatment decreased Mn concentration and manganese-containing superoxide dismutase (MnSOD) activity in the heart when compared with L-Fe and M-Fe treatments. Dietary Fe did not significantly influence Mn concentrations in the liver and heart, and heart MnSOD activity in Mn-unsupplemented broilers. In the duodenum, L-Fe treatment decreased divalent metal transporter 1 (DMT1) mRNA abundance when compared with M-Fe and H-Fe treatments, and ferroportin 1 (FPN1) mRNA level was higher in M-Fe treatment than that in L-Fe and H-Fe treatments. These results suggested H-Fe diet decreased Mn status in broilers evaluated by Mn concentrations in serum and heart, and heart MnSOD activity. Dietary Fe influenced Mn absorption possibly through effects on duodenal DMT1 and FPN1 expression.

Relative bioavailability of humate-manganese complex for broilers fed a corn-soya bean meal diet

The experiment was conducted to investigate the bioavailability of manganese (Mn) from humate-Mn complex relative to Mn sulphate for the starter broilers fed a conventional corn-soya bean meal diet. A total of 560 1-day-old Arbor Acres male broiler chicks were randomly allotted to one of eight replicate cages (10 chicks per cage) for each of seven treatments in a completely randomized design involving a 2 × 3 factorial arrangement of treatments with two Mn sources (humate-Mn and Mn sulphate) and three levels of added Mn (60, 120 or 180 mg Mn/kg) plus a Mn-unsupplemented control diet containing 27.23 mg Mn/kg by analysis. At 14 days of age, the blood, liver, heart and tibia were collected for Mn analyses, and the activity and mRNA abundance of heart manganese superoxide dismutase (MnSOD). The results showed that humate-Mn supplementation decreased feed intake from day 1 to day 14, whereas it did not influence (p > 0.20) body weight at day 14 as compared to Mn sulphate. The Mn source did not influence Mn concentration in the liver, heart and tibia, and the activity and mRNA abundance of heart MnSOD, while humate-Mn decreased plasma Mn as compared to Mn sulphate. The Mn concentration in the plasma and heart, and the activity and mRNA abundance of heart MnSOD increased linearly as dietary Mn concentration increased. Based on slope ratios from multiple linear regressions of Mn concentrations in the plasma and heart, and the activity and mRNA abundance of heart MnSOD on daily intake amount of dietary analysed Mn, the bioavailability of humate-Mn complex relative to Mn sulphate (100%) was 82.8, 90.4, 82.8 and 81.9 respectively. These results indicated that the Mn from humate-Mn complex was just as bioavailable as the Mn from Mn sulphate for the starter broilers (day 1-14).

Relative bioavailability of ultrafine sodium selenite for broilers fed a conventional corn-soybean meal diet

The particle size of selenium (Se) sources could affect Se absorption and utilization, and thus it is hypothesized that the Se bioavailability might be higher in ultrafine sodium selenite (USSe) than in sodium selenite (SSe) for broilers because of USSe's smaller particle size. An experiment was conducted to investigate the relative bioavailability of Se as USSe relative to SSe for broiler chicks fed a conventional corn-soybean meal diet. A total of 504 one-d-old Arbor Acres commercial male broilers were randomly allotted to 1 of 7 treatments with 6 replicates per treatment in a completely randomized design involving in a 2 (Se sources) × 3 (added Se levels) factorial arrangement of treatments plus a Se-unsupplemented control diet containing 0.05 mg Se/kg by analysis for 21 d. The 2 Se sources were USSe and SSe, and the 3 added Se levels were 0.15, 0.30, or 0.45 mg Se/kg. The Se concentrations, glutathione peroxidase (GSH-Px) activities, and mRNA relative abundances in plasma, liver, or pancreas of broilers on day 14 and 21 were determined. The results showed that Se concentrations, GSH-Px activities in plasma, liver, and pancreas, and mRNA relative abundances in the liver and pancreas of broilers on day 14 and 21 increased linearly (P < 0.05) as the added Se-level increased. Furthermore, a difference (P < 0.05) between USSe and SSe was detected for GSH-Px mRNA relative abundance in the pancreas of broilers on day 14. On the basis of the slope ratios from the multiple linear regression of the pancreatic GSH-Px mRNA relative abundance of broilers at 14 d of age on daily dietary analyzed Se intake, the Se bioavailability of USSe relative to SSe (100%) was 158% (P < 0.05). The results from this study indicated that the Se from USSe was more available to broilers than the Se from SSe in enhancing the pancreatic GSH-Px mRNA expression.

Effect of zinc concentration and source on performance, tissue mineral status, activity of superoxide dismutase enzyme and lipid peroxidation of meat in broiler chickens

The present experiment was conducted to investigate the effect of feeding different concentrations and the source of zinc (Zn) on the performance, tissue mineral status, superoxide dismutase (SOD) enzyme activity and meat quality in 0–4-week-old broiler chicks. Dietary treatments included the corn–soybean meal-based diet (control) and the basal diet supplemented with Zn at 20, 50 or 80 mg/kg, added as ZnSO4, Zn-methionine or Zn-enriched yeast. The results showed that birds fed Zn-supplemented diets had higher average weight gain and average feed intake than did birds fed the control diet (P < 0.01). At the end of the experiment, the Zn deposition in pancreas, liver and tibia increased (P < 0.01), regardless of the source, in response to increasing dietary Zn concentrations, whereas plasma Zn status was significantly increased by the highest Zn supplementation level. The main effect of Zn supplementation level was significant for the activities of Cu and/or Zn SOD in the liver and pancreas (P < 0.01). As broiler given 50 mg Zn had higher tissue SOD activity than did broilers fed the other treatment diets. Furthermore, Zn supplementation at up to 50 mg/kg significantly increased (P < 0.01) Zn accumulation and SOD activity and decreased lipid peroxidation in muscles around the femur bone. Results from the present study demonstrated that supplementation with 50 mg Zn may be sufficient for normal broiler growth to 28 days of age and the dietary inclusion of organic Zn could be utilised more effectively than that of inorganic sources.

The chemical characteristics of organic iron sources and their relative bioavailabilities for broilers fed a conventional corn-soybean meal diet

Twenty-four organic Fe sources were evaluated by polarographic analysis and via solubility in buffers (pH 5 and 2) and deionized water. Organic Fe sources included 6 Fe-Met complexes (Fe-Met), 10 Fe-Gly complexes, 1 Fe-Lys complex, 4 Fe proteinates, and 3 Fe-AA complexes (Fe-AA). Sources varied considerably in chemical characteristics. Chelation strengths (quotient of formation [Q] values) ranged from weak (Q = 1.08) to extremely strong strength (Q = 8,590). A total of 1,170 1-d-old Arbor Acres male broilers were randomly allotted to 6 replicate cages (15 chicks/cage) for each of 13 treatments in a completely randomized design involving a 4 × 3 factorial arrangement of treatments (4 Fe sources × 3 added Fe levels) plus a control with no added Fe. Dietary treatments included a corn-soybean meal basal diet (control; 55.8 mg Fe/kg) and the basal diet supplemented with 20, 40, or 60 mg Fe/kg as iron sulfate (FeSO∙7HO); an Fe-Met with weak chelation strength (Fe-Met W; Q = 1.37; 14.7% Fe); an iron proteinate with moderate chelation strength (Fe-Prot M; Q = 43.6; 14.2% Fe); or an iron proteinate with extremely strong chelation strength (Fe-Prot ES; Q = 8,590; 10.2% Fe). The growth performance, Fe concentrations, hematological indices, and activities and gene expressions of 2 Fe-containing enzymes in tissues of broilers at 7, 14, and 21 d of age were determined in the present study. Transferrin saturation in plasma on 14 d; bone Fe on d 7 and 14; liver Fe on d 7, 14, and 21; kidney Fe on d 14; succinate dehydrogenase activities in the liver on d 21 and in the kidney on d 7 and 21; mRNA levels in the kidney and heart on d 14; and mRNA levels in the liver and kidney on d 21 linearly increased ( < 0.05) as added Fe levels increased. However, differences in bioavailabilities among Fe sources were detected ( < 0.05) only for the mRNA levels in the liver and kidney on d 21. Based on slope ratios from the multiple linear regression of mRNA level in the liver or kidney of broilers on d 21 on daily dietary analyzed Fe intake, the bioavailabilities of Fe-Met W, Fe-Prot M, and Fe-Prot ES relative to iron sulfate (100%) were 129 ( = 0.18), 164 ( < 0.003), and 174% ( < 0.001) or 102 ( = 0.95), 143 ( = 0.09), and 174% ( < 0.004), respectively. These results indicated that the relative bioavailabilities of organic Fe sources were closely related to their Q values and organic Fe sources with greater Q values showed higher Fe bioavailabilities.

Dietary manganese supplementation influences the expression of transporters involved in iron metabolism in chickens

To investigate the effects of dietary manganese (Mn) supplementation on iron (Fe) metabolism, a total of 480 50-week-old hens were fed the basal diet (control, 24.35 mg Mn/kg) without Mn supplementation for 6 weeks to reduce Mn storage in the body. Hens were then randomly assigned to one of three treatments, which included the control and control added with 60 or 300 mg Mn/kg diet (M-Mn or H-Mn). Duodenum, heart, liver, and tibia were collected in hens after 12-week feeding period. No significant differences were observed in egg production, feed/egg ratio, shell breaking strength, and shell thickness among different treatments. Compared with control or M-Mn, H-Mn decreased (P < 0.05) serum Fe concentration, while increased (P < 0.05) total Fe-binding capacity (TIBC). The Fe concentration decreased (P < 0.05) in duodenum, and tended to reduce (P < 0.10) in liver from control to M-Mn and to H-Mn; whereas, dietary Mn supplementation did not influence (P > 0.10) Fe concentration in the heart and tibia. In conjunction with reduced Fe retention, DMT1 mRNA expression decreased (P < 0.05) with dietary Mn concentration increasing in the duodenum and liver. Duodenal FPN1 mRNA level was higher (P < 0.05) in H-Mn group than that in control or M-Mn group, while hepatic FPN1 mRNA expression was lower (P < 0.05) in M-Mn or H-Mn group when compared with control. The results demonstrated that dietary Mn supplementation decreased Fe concentration in duodenum and liver of hens, which may be related to the alteration of DMT1 and FPN1 expression in these tissues.

Copper in organic proteinate or inorganic sulfate form is equally bioavailable for broiler chicks fed a conventional corn-soybean meal diet

An experiment was conducted to investigate the bioavailability of organic copper (Cu) proteinate relative to inorganic Cu sulfate for broiler chicks fed a conventional corn-soybean meal basal diet. A total of 320 day-old Arbor Acres commercial male chicks were assigned to one of five treatments in a completely randomized design involving a 2 × 2 factorial arrangement with two levels of added Cu (125 or 250 mg Cu/kg) and two Cu sources (Cu proteinate and Cu sulfate) plus a control with no added Cu for an experimental phase of 42 days. Plasma and liver tissue samples were collected at both 21 and 42 days of age, and bile samples were also obtained at 42 days of age for Cu analyses. The Cu concentrations in liver and bile increased linearly (P < 0.001) on both days 21 and 42 as dietary Cu levels increased. No significant (P > 0.17) linear regression relationships were observed between plasma Cu concentrations on days 21 and 42 or log10 liver Cu concentration on day 21 and daily analyzed Cu intake. Therefore, based on the slope ratios from multiple linear regressions of log10 liver and bile Cu concentrations with daily analyzed Cu intake on day 42, when Cu sulfate was set as 100%, the estimated relative bioavailability values of Cu proteinate were 78.8% for log10 liver Cu concentration and 79.3% for log10 bile Cu concentration, respectively. There was no significant (P > 0.08) difference in bioavailability between Cu proteinate and Cu sulfate for broilers chicks in this experiment.