Uptake of zinc from zinc sulfate and zinc proteinate by ovine ruminal and omasal epithelia

Effects of sources and levels of dietary supplementary manganese on growing yak's in vitro rumen fermentation

Introduction

Manganese (Mn) is an essential trace element for livestock, but little is known about the optimal Mn source and level for yak.

Methods

To improve yak's feeding standards, a 48-h in vitro study was designed to examine the effect of supplementary Mn sources including Mn sulfate (MnSO₄), Mn chloride (MnCl₂), and Mn methionine (Met-Mn) at five Mn levels, namely 35 mg/kg, 40 mg/kg, 50 mg/kg, 60 mg/kg, and 70 mg/kg dry matter (includes Mn in substrates), on yak's rumen fermentation.

Results

Results showed that Met-Mn groups showed higher acetate (p < 0.05), propionate, total volatile fatty acids (p < 0.05) levels, ammonia nitrogen concentration (p < 0.05), dry matter digestibility (DMD), and amylase activities (p < 0.05) compared to MnSO4 and MnCl2 groups. DMD (p < 0.05), amylase activities, and trypsin activities (p < 0.05) all increased firstly and then decreased with the increase of Mn level and reached high values at 40-50 mg/kg Mn levels. Cellulase activities showed high values (p < 0.05) at 50-70 mg/kg Mn levels. Microbial protein contents (p < 0.05) and lipase activities of Mn-Met groups were higher than those of MnSO4 and MnCl2 groups at 40-50 mg/kg Mn levels.

Discussion

Therefore, Mn-met was the best Mn source, and 40 to 50 mg/kg was the best Mn level for rumen fermentation of yaks.

Zinc supplementation improves growth performance in small ruminants: a systematic review and meta-regression analysis

Appropriate supplementation of trace minerals is fundamental to enhance the metabolic status of growing animals and promote an adequate expression of genetic potential. Zinc (Zn) is an essential mineral fundamental in many biological processes that are related to growth, energy balance and immunity. The aim of the present study was to analyse the effect of Zn supplementation on growth parameters in small ruminants by using a meta-analytic approach. Sources of heterogeneity were explored using a meta-regression analysis. The final database was integrated from a total of 53 trials. Only indexed articles that provided an effect size measure, variability measure, sample size and randomisation of the procedure were considered. The dependent variables considered for the study were average daily gain (ADG), dry-matter intake (DMI), feed conversion ratio (FCR), final bodyweight, and glucose blood concentration. The exploratory variables included species (sheep and goat), breed, production level, Zn source and dosage. The ‘meta’ package in R statistical software was used to conduct the meta-analyses. For response variables that showed substantial heterogeneity (I2 &gt; 50%), mixed-effect models (meta-regression analysis) were constructed to explore the sources of heterogeneity using the ‘Metafor’ package. DMI was higher in animals supplemented with Zn (&gt;21.08 g/day, P = 0.0001). Breed, species, production level, and dosage reduced heterogeneity of DMI response from I2 = 84.8 to I2 = 48.1%. Zn-supplemented animals showed higher ADG (17.39 g/day, P = 0.001), which was affected by species, breed dosage and Zn-source. Zn supplementation improved feed efficiency, with lower values of FCR (–1.56 g/g, P &lt; 0.0001). There was a positive relationship between the dosage and effect size in all outcome variables (P &lt; 0.05). Zn-proteinate showed the best response in both species to ADG, FCR and final body weight. Our findings of the systematic review concluded that dietary Zn supplementation improves growth performance in small ruminants and their level of response is influenced mainly by species, production level, and Zn-source and dosage.

Effects of different dietary manganese sources on thickness of mucus layer and selected biochemical and haematological indicators in sheep

The effects of manganese from organic and inorganic sources supplemented to diets of sheep on intestinal mucus production and on selected biochemical and haematological indicators were investigated. The experiment was carried out on 18 sheep of the Improved Valachian breed aged seven months over the period of four months. The animals were divided into three groups of six animals each (group 1 – control, basal diet with 31 mg Mn/kg, group 2 – basal diet + manganese sulphate (MnSO4) with 120 mg Mn/kg, group 3 – basal diet + manganese chelate of glycine hydrate (Mn-Gly) with 120 mg Mn/kg). Intestinal segments (duodenum, jejunum, ileum, caecum) were collected and mucus production was assessed using the quantification method. Mucus production in the duodenum and jejunum was significantly lower (P < 0.05) in group 3 (Mn-Gly) compared to the control and group 2 (MnSO4). In the duodenum in group 2 (MnSO4) mucus production was similar to the control. Biochemical indicators were determined using spectrophotometry, and haematological indicators were measured using a haematology analyzer. Significant changes (P < 0.05) were found for the concentrations of total proteins and albumins. The concentration of total proteins was lower in group 3 (Mn-Gly) compared to the control and group 2 (MnSO4). In the latter group it was higher compared to the control. The concentration of albumins was higher in group 3 (Mn-Gly) compared to the control and group 2 (P < 0.05). The results indicate a decrease of intestinal mucus in the group supplemented by Mn-Gly chelate, which may mean a lower mucus barrier for manganese absorption.

Dietary manganese source does not affect Mn, Zn and Cu tissue deposition and the activity of manganese-containing enzymes in lambs

Manganese (Mn) is a trace element required for normal physiological processes in animals and humans. Organic forms of trace elements are expected to have higher bioavailability in comparison with inorganic sources. The effect of feeding a diet supplemented with different sources of manganese to lambs was studied in a 112-d feeding trial. The aim of this study was to investigate the deposition of Mn in relation to activities of superoxide dismutase (SOD), manganese superoxide dismutase (MnSOD) and arginase in the tissues of lambs fed the diet supplemented with an inorganic or an organic source of manganese up to the maximum total Mn content allowed in the European Union (150mg Mn/kg). A total of eighteen female lambs of the improved Valachian breed were randomly allocated to three dietary treatments and fed an unsupplemented basal diet (Control, 31mg Mn/kg) or the identical diet supplemented with manganese sulphate (MnSO₄) or manganese chelate of glycine hydrate (Mn-Gly) with a total Mn content up to 150mg/kg. Regardless of the source, feed supplementation with manganese increased Mn concentrations in plasma (P˂0.05) and the liver (P˂0.001) as well as the activity of liver MnSOD (P˂0.05) and arginase (P˂0.001) compared with the control lambs. In the kidney cortex, the concentration of Mn was greatest in lambs fed the diet supplemented with the chelated Mn source compared with animals receiving the inorganic Mn source (P˂0.05) and the unsupplemented diet (P˂0.001). The 112-d intake of feed enriched with manganese did not result in any change in Mn levels, SOD or MnSOD activity in pancreas and kidney tissues. Plasma Cu concentration was depressed in both supplemented treatments. No analyzed tissue showed a change in zinc and copper levels, except the greater Cu concentration in the liver of lambs fed the diet with Mn-Gly. The presented results did not indicate any differences between dietary Mn sources either in Mn tissue deposition or activity of SOD, MnSOD and arginase in lamb tissues; however, it seems that manganese intake of up to 150mg/kg in feed may decrease plasma Cu concentration in lambs.

Effects of chelated Zn/Cu/Mn on redox status, immune responses and hoof health in lactating Holstein cows

To evaluate the effects of chelated Zn/Cu/Mn on redox status, immune responses and hoof health in lactating Holstein cows, 48 head in early lactation were divided into healthy or lame groups according to their gait score. Cows were fed the same amount of Zn/Cu/Mn as sulfate salts or in chelated forms for 180 days, and foot-and-mouth disease (FMD) vaccine was injected at day 90. The results showed that lame cows had lower antioxidant function, serum Zn/Mn levels, hair Cu levels, and hoof hardness. Moreover, increased antioxidant status, FMD antibody titers, serum and hair levels of Zn/Cu/Mn, and hoof hardness and decreased milk fat percent and arthritis biomarkers were observed in cows fed chelated Zn/Cu/Mn. In summary, supplementation with chelated Zn/Cu/Mn improved antioxidant status and immune responses, reduced arthritis biomarkers, and increased accumulation of Zn/Cu/Mn in the body and hoof hardness in dairy cows.

The bioavailability of different zinc compounds used as human dietary supplements in rat prostate: a comparative study

The normal human prostate accumulates the highest levels of zinc (Zn) of any soft tissue in the body. The pool of zinc available to the body is known to significantly decrease with age. It is suggested that dietary Zn supplementation protects against oxidative damage and reduces the risk of cancer. Zinc sulfate and zinc gluconate were the most frequently mentioned in per os administration in studies on Zn supplementation. The major aim of the study was to compare the bioavailability of different Zn compounds (sulfate, gluconate and citrate) in the prostate after their daily administration to male rats at three different doses (3.0; 15.0; and 50.0 mg Zn/kg b.w.) for 30 days. The results show that bioavailability in the prostate differs significantly between individual zinc preparations. A significantly elevated Zn concentration in the dorso-lateral lobe of the prostate, compared to controls, was found in the rats supplemented with two compounds only: zinc gluconate and zinc citrate. However, after administration of zinc gluconate, this effect occurred even at the lowest dose. The lowest zinc bioavailability in the prostate was found in the rats administered zinc sulfate: no significant Zn increase was seen in particular zones of the prostate. To sum up, the use of zinc gluconate is worth considering as a possible means of zinc supplementation in men.

Effects of peroral supplementation of different forms of zinc on the ruminal mucosa of goat kids – a morphometric study

The aim of the study was to identify the effect of supplementation of various forms of zinc on the ruminal mucosa and dimensions of ruminal papillae in 6-month-old goat kids. The experimental period lasted from weaning to slaughter (4 months). All 20 kids divided into four groups of five animals, were fed with the same feeding dose, which was different only in the quantity and form of zinc. Control group was without additional zinc supplementation (group A), the other groups were supplemented with zinc in the form of ZnO (group B), zinc in the form of chelate (group C) and zinc in the form of lactate (group D). Samples for histopathological and morphometric examination were collected after the slaughter of all animals from the bottom of saccus ruminis ventralis everytime from the same place. Significant differences were reported within the comparison of the length of ruminal papillae between groups B and C (P = 0.026) and B and D (P = 0.040), within the comparison of the width of ruminal papillae between groups A and D (P = 0.020) and within the comparison of the intensity of keratinisation of the mucosa of ruminal papillae between groups A and B (P = 0.034), A and C (P = 0.038) and A and D (P = 0.001). Histopathological and morphometric examination of ruminal mucosa indicated that the ruminal papillae of kids supplemented with zinc in the form of ZnO (group B) were better developed compared to the other groups. This result indicates better utilisation of the supplemented zinc in the form of ZnO.