Comparison of Zinc Sulfate and Zinc Threonine Based on Zn Bioavailability and Performance of Broiler Chicks

Zinc glycinate alleviates LPS-induced inflammation and intestinal barrier disruption in chicken embryos by regulating zinc homeostasis and TLR4/NF-κB pathway

The effect of an immune challenge induced by a lipopolysaccharide (LPS) exposure on systemic zinc homeostasis and the modulation of zinc glycinate (Zn-Gly) was investigated using a chicken embryo model. 160 Arbor Acres broiler fertilized eggs were randomly divided into 4 groups: CON (control group, injected with saline), LPS (LPS group, injected with 32 µg of LPS saline solution), Zn-Gly (zinc glycinate group, injected with 80 µg of zinc glycinate saline solution) and Zn-Gly+LPS (zinc glycinate and LPS group, injected with the same content of zinc glycinate and LPS saline solution). Each treatment consisted of eight replicates of five eggs each. An in ovo feeding procedure was performed at 17.5 embryonic day and samples were collected after 12 hours. The results showed that Zn-Gly attenuated the effects of LPS challenge-induced upregulation of pro-inflammatory factor interleukin 1β (IL-1β) level (P =0.003). The LPS challenge mediated zinc transporter proteins and metallothionein (MT) to regulate systemic zinc homeostasis, with increased expression of the jejunum zinc export gene zinc transporter protein 1 (ZnT-1) and elevated expression of the import genes divalent metal transporter 1 (DMT1), Zrt- and Irt-like protein 3 (Zip3), Zip8 and Zip14 (P < 0.05). A similar trend could be observed for the zinc transporter genes in the liver, which for ZnT-1 mitigated by Zn-Gly supplementation (P =0.01). Liver MT gene expression was downregulated in response to the LPS challenge (P =0.004). These alterations caused by LPS resulted in decreased serum and liver zinc levels and increased small intestinal, muscle and tibial zinc levels. Zn-Gly reversed the elevated expression of the liver zinc finger protein A20 induced by the LPS challenge (P =0.025), while Zn-Gly reduced the gene expression of the pro-inflammatory factors IL-1β and IL-6, decreased toll-like receptor 4 (TLR4) and nuclear factor kappa-B p65 (NF-κB p65) (P < 0.05). Zn-Gly also alleviated the LPS-induced downregulation of the intestinal barrier gene Claudin-1. Thus, LPS exposure prompted the mobilization of zinc transporter proteins and MT to perform the remodeling of systemic zinc homeostasis, Zn-Gly participated in the regulation of zinc homeostasis and inhibited the production of pro-inflammatory factors through the TLR4/NF-κB pathway, attenuating the inflammatory response and intestinal barrier damage caused by an immune challenge.

Dietary collagen peptide-chelated trace elements supplementation for breeder hens improves the intestinal health of chick offspring

BACKGROUND

Dietary supplementation with trace elements zinc (Zn), iron (Fe) and manganese (Mn) could promote intestinal development and improve intestinal health. There are, however, few studies examining the possibility that maternal original Zn, Fe and Mn could regulate intestinal development and barrier function in the offspring. This study aimed to investigate how the intestinal growth and barrier function of breeder offspring were affected by collagen peptide-chelated trace elements (PTE; Zn, Fe, Mn).

RESULTS

PTE supplementation in the diet of breeder hens increased the concentrations of Zn, Fe and Mn in egg yolk. Maternal PTE supplementation improved morphological parameters of the intestine (villi height, crypt depth and villi height/crypt depth) and upregulated the mRNA expression level of leucine-rich repeat-containing G protein-coupled receptor 5 (Lgr5) in the ileum of chick embryos. Furthermore, maternal PTE effect improved villi height/crypt depth of offspring at 1 and 14 days of age, and upregulated Lgr5, Claudin-3 and E-cadherin mRNA expression in the broiler ileum. Additionally, PTE treatment could enhance the intestinal microbial diversity of offspring. Maternal PTE supplementation increased the relative abundance of Clostridiales at the genus level and decreased the relative abundance of Enterococcus in newborn offspring. Moreover, maternal PTE supplementation ameliorated the elevated nuclear factor kappa B, toll-like receptor 4 and interleukin 1β mRNA expression in the ileum of offspring caused by LPS challenge.

CONCLUSION

Maternal PTE supplementation could promote intestinal development and enhance the intestinal barrier function of chicken offspring. © 2023 Society of Chemical Industry.

Effects of Different Levels of Dietary Zinc-Threonine and Zinc Oxide on the Zinc Bioavailability, Biological Characteristics and Performance of Honey Bees (Apis mellifera L.)

The experiment was conducted to investigate the effect of supplementary different levels of zinc-threonine (Zn-Thr) and zinc oxide (ZnO) on the Zn bioavailability, biological characteristics and performance of honey bees (Apis mellifera L.). The experiments were carried out with seven treatments in a completely randomized design with five replicates for each treatment. During the experiment, groups were fed a basal diet without extra zinc (10.4 mg Zn/kg diet), and it was used as the control diet and 3 levels of 20, 40, and 60 mg Zn/kg were added to the diet by ZnO and Zn-Thr sources. The results showed that different levels of organic Zn significantly increased Zn and Fe content in the carcass of caged bees compared to different levels of inorganic Zn and control groups. Also, honey bees fed with levels of 40 and 60 mg Zn/kg Zn-Thr supplementation significantly had lower Malondialdehyde (MDA) concentration and higher ash content, protein content, superoxide dismutase (SOD) activity in their tissues. In addition, they showed more life span, feed intake, population, brood rearing, and hive weight gain (p < 0.05). Totally, the results of the present experiments revealed that diets supplied with organic Zn compared to inorganic Zn play significant roles in the improvement of Zn bioavailability, biological characteristics, and performance in honey bees.

Effect of Two Particle Sizes of Nano Zinc Oxide on Growth Performance, Immune Function, Digestive Tract Morphology, and Intestinal Microbiota Composition in Broilers

The effects of dietary supplementation with two particle sizes of nano zinc oxide (ZnO) on growth performance, immune function, intestinal morphology, and the gut microbiome were determined in a 42-day broiler chicken feeding experiment. A total of 75 one-day-old Arbor Acres broilers were randomized and divided into three groups with five replicates of five chicks each, including the conventional ZnO group (NC), the nano-ZnO group with an average particle size of 82 nm (ZNPL), and the nano-ZnO group with an average particle size of 21 nm (ZNPS). Each group was supplemented with 40 mg/kg of ZnO or nano-ZnO. Our results revealed that birds in the ZNPS group had a higher average daily gain and a lower feed-to-gain ratio than those in the NC group. ZNPS significantly increased the thymus index and spleen index, as well as the levels of serum metallothionein (MT), superoxide dismutase (SOD), and lysozyme (LZM). The ZNPS treatments reduced interleukin (IL)-1β and tumor necrosis factor-alpha (TNF-α) levels and increased IL-2 and interferon (IFN)-γ levels compared to that in the NC group. Additionally, compared with the birds in the NC group, those in the nano-ZnO group had a higher villus height to crypt depth ratio of the duodenum, jejunum, and ileum. Bacteroides increased in the ZNPS group at the genus level. Further, unidentified_Lachnospiraceae, Blautia, Lachnoclostridium, unidentified_Erysipelotrichaceae, and Intestinimonas were significantly increased in the ZNPL group. In conclusion, nano-ZnO improved the growth performance, promoted the development of immune organs, increased nonspecific immunity, improved the villus height to crypt depth ratio of the small intestine, and enriched the abundance of beneficial bacteria. Notably, the smaller particle size (21 nm) of nano-ZnO exhibited a more potent effect.

Hydroxychloride trace elements improved eggshell quality partly by modulating uterus histological structure and inflammatory cytokines expression in aged laying hens

The objectives of this study were to investigate the effectiveness of dietary zinc, copper, and manganese hydroxychloride (HC) supplementation on performance, minerals deposition, serum parameters, eggshell ultrastructure, uterus histological structure, and inflammatory cytokines in aged hens. A total of 560 Hyline Brown layers at 62 wk of age were randomly allotted into 3 groups (CON, basal diet without extra minerals supplemented; Sulphate and HC, basal diet with sulphate or hydroxychloride zinc, copper, and manganese supplementation at levels of 80, 15, and 80 mg/kg, respectively). The trial lasted for 16 wk consisting of 4 wk depletion period and 12 wk testing period. The results indicated that dietary hydroxychloride trace elements increased egg weight (P < 0.05) when compared with CON group and improved average Haugh unit and albumen height (P < 0.05) when compared with Sulphate group from 70 to 73 wk. Trace element supplementation significantly increased eggshell strength, ceruloplasmin content in serum, and modified crystallographic structure of eggshell (P < 0.05) that included effective layer height, palisade height, mammillary layer width, and mammillary internal area ratio, but the results did not differ regarding the trace mineral sources used. Furthermore, hens fed with hydroxychloride trace element showed the highest mucosal fold height (P < 0.05) and epithelial height (P = 0.053) in eggshell gland, as well as mRNA expression of TNF-α (P < 0.05) and IL-22 (P = 0.094). It is concluded that supplementation of Zn, Cu, and Mn mixture modified eggshell quality partly through enhancing histological structure and immune responses of uterus. Hydroxychloride source of Zn, Cu, and Mn excelled sulphate in its beneficial effects for birds.

The effect of Cu, Zn and Fe chelates on the antioxidative status of thigh meat of broiler chickens

The studies aimed to verify the effect of Cu, Zn and Fe glycine chelate on the antioxidative status in the thigh meat of broiler chickens. The study assumption was that due to the antioxidative or prooxidative effect of Cu, Zn and Fe, these elements supplemented to chickens in an easily assimilable form would modify the antioxidative status of meat and those having a prooxidative effect could deteriorate the quality of meat. The experiment involved three hundred and fifty Ross 308 chickens divided into seven equipotent experimental groups. Over 42 days of the experiment, the chickens were administered Cu, Zn and Fe glycine chelates in an amount corresponding to 50% of the requirement (experimental factor I) or 25% of the requirement (experimental factor II). The level of oxidative stress indicators such as superoxide dismutase, catalase, glutathione, glutathione peroxidase and malondialdehyde was determined in the muscles and blood. The groups receiving Zn or Cu chelate showed statistically confirmed higher activity of superoxide dismutase, catalase, and a higher level of glutathione in comparison to the group receiving Fe chelate. In order to increase the antioxidative stability of thigh meat, it is sufficient that broiler chickens receive Zn or Cu in the form of glycine chelate in an amount covering 25% of their requirement of such minerals. On the other hand, the use of Fe glycine chelates decreased antioxidative stability due to an increase in the level of malondialdehyde, so it should be considered whether the administration of pro-oxidative Fe chelate to broilers is advisable.