Nano Zinc Prospects for Poultry

Industry and zinc in poultry

With the rise in demand for high quality poultry feed, Poultry farmers and Feed manufactures are always on a lookout for poultry health and growth promoters. Zinc (Zn) is an important microelement in poultry nutrition. Zinc is vital for proliferation of cells and their differentiation. The importance of zinc in nutritional biology was first reported by Raulin (1869), when he observed that zinc was required for growth of Aspergillus Niger. The enzyme carbonic anhydrase was identified and purified in 1940. It contains a metalloenzyme zinc at 0.33%, which catalyses the breakdown of carbonic acid into CO₂ and H₂O.Being a component of carbonic anhydrase, zinc facilitates transport of CO₂ from tissues to lungs. Zinc is an essential component of both DNA and RNA polymerase enzymes. Zinc has been found cofactor in more than 300 metallo-enzymes which is essential for enzyme structure, bone development and growth. It is vital to the activity of a variety of hormones including glucagon, insulin, growth hormone, and the sex hormones. It also plays a key role in the immune system. Consumers, producers, Poultry feed manufacturers and others related with poultry industry has developed a good attraction towards the role of zinc in poultry nutrition.

Zinc as antioxidant.

Zinc is an indispensable part of the antioxidant system in animals. Antioxidants combat ‘reactive oxygen species’ (ROS) and protect the body from the harmful effects of ROS, in various ways. Zn is a major part of the antioxidant enzyme superoxide dismutase (SOD), which helps defend the body against ROS by converting superoxide anions into hydrogen peroxide. Zn reduces oxidative stress by antagonism of the redox-active transition metals (inorganic copper and iron), preventing the formation of hydroxyl radicals from hydrogen peroxide (H₂O₂). Zinc interferes in the Fenton reaction, by competing with the binding sites of transition metals (iron, copper, and zinc), serving as, a donor of electrons for such reactions.

Zn appears to indirectly suppress oxidant stress by the stimulation of certain substances which have antioxidant properties. It effects in two ways; acutely and chronically. The acute effects of Zn include antagonism to redox-active transition metals and by protection of protein sulphahydryls; while chronic effects involve indirect protection from pro-oxidants due to induction of other substances, e.g., metallothionein, which are cysteine rich proteins that serve as antioxidants by scavenging ROS. Zinc-dependent metallothionein are found in different forms in animals, especially in the pancreas, liver, intestine, and kidney of chickens, where it serves as an antioxidant in these tissues and, under different conditions of oxidative stress such as toxicity of certain drugs, they prevent oxidative DNA damage and mutagenesis and ethanol toxicity.

Zinc as immunomodulatory agent.

Immunity and stress related issues are pivotal for the poultry production. Studies have shown overwhelming evidence that supplementation of Zinc can improve growth, augment immunity, enhance antioxidant capacity, increase endocrine secretion, and interact with other minerals in the gut. The effectiveness of Zn depends upon its absorption from the gut and bioavailability in blood.  Zinc acts as a non-pharmacologic booster for immunity in broiler chicks and as a stimulator for cellular and humoral immune system.

Zinc as a moulting inducer.

Over-supplementation with Zn as an alternative agent for the induction of moulting agent for layer hens, which produced more eggs of higher quality in the second production cycle as compared to other methods of moulting. Chickens tend to lose weight during the process of moulting; however, the weight loss was temporary and body weight recovered after the resting period in supplemented hens. It has been postulated that high concentration of Zn (10,000-20,000 mg/kg) in feed of laying hens causes the follicular atresia followed by cessation of eggs. Zinc interferes in availability of calcium (Ca) which plays an important role in gonadotrophin secretion (LH) which is required for the egg laying process.

Zinc and Egg

Zn has been reported to increase the overall egg production of laying hens. Increased mineral deposition in the eggs of laying hens has been seen after supplementation with organic forms of Zn alone, and in combination with other trace minerals, copper, manganese, and chromium. Better egg quality in terms of increased egg mass, egg albumin, globulin, shell thickness and total protein in laying hens after Zn supplementation. Macro-minerals like calcium and phosphorous, and vitamin D₃ are major nutrients which are responsible for eggshell quality in laying birds. Additionally, for mineralization process some enzymes are linked with macro-minerals. One of the enzymes is carbonic anhydrase, a zinc dependent enzyme essential for supplying carbonate ions to convert calcium into calcium carbonate needed for eggshell formation in laying hens. Zinc concentration in birds is directly related to activity of this carbonic anhydrase enzyme. Zinc and manganese are cofactors of metalloenzymes which are responsible for carbonate and mucopolysaccharides synthesis and are important in eggshell formation. The increase in egg production and enhanced production performance after Zn supplementation has been attributed to its anti-stress and anti-oxidative properties.

Zinc and reproductive health.

Zn has been found in high amounts in the male reproductive tract and plays an important role in physiology of spermatozoa and the cases of its deficiency has been associated with reproductive dysfunction including shrinkage of seminerfous tubules and lower testicular weight. It has been suggested that Zn can bind with free radicals produced by abnormal spermatozoa and thus prevent healthy sperm from the damage of oxygen reactive species. Zn is also part of copper-zinc superoxide dismutase and cofactor of metalloenzymes and thus involved in important functions inside the spermatozoa. Zn has a vital role in breeders in terms of improving the egg production, fertility, hatchability, embryonic development, and availability of the hatched chicks.

Zinc and Bone Health

Zinc has been postulated to have a stimulatory impact on mineralisation, formation of bone and the preservation of bone mass. The metal directly activates aminoacyl-tRNA syntheses in osteoblastic cells, and it activates synthesis of cellular protein. Furthermore, Zn deactivates osteoclastic bone resorption through inhibiting osteoclast-like cell formation from marrow cells.

Zinc and Feather

Zinc is a component of 1000 transcription proteins, and it has been suggested that the alteration in Zn status affects the gene expression of a plenty of genes by activation. As a reflection of its role in gene regulation, it is required for the synthesis of different proteins. Two key structure proteins, keratin, and collagen, both require Zn. Any deficiency leads to decreased keratin and collagen formation leading to some deficiency signs such as poor feathering in poultry.

Zinc Deficiency

Reduced appetite is the first sign to be noted in Zn deficiency which further leads to loss of taste. The sense of taste is mediated through the salivary zinc dependent polypeptide. Low salivary zinc concentration leads to a reduction of taste and reduced appetite.

In chicks its deficiency results in various bone abnormalities, skeletal malformations, poor bone mineralisation, stunted growth, and immunological dysfunctions. In layers’ deficiency of Zn is accounted to decreased egg hatchability Several trials have shown improvements in production from poultry when Zn was added to the diet. Improvement in terms of body weight gain, better egg production and egg quality in laying hens.

Supplementation of high dietary Zn in chicken results in elevated levels of Zn in the liver, kidney, pancreas, spleen, and gizzard. Dietary Zn supplementation has an inverse relationship with Fe and Cu content of the liver in laying hens. while the copper content of the liver, pancreas and gizzard decreased with increasing Zn supplementation in the feed.

Recommended Dosage

The commonly used cereal grains in broilers diets are rich in phytate that may reduce absorption of zinc. Zinc is not always readily available in the diet of poultry, which is why it is often added to commercial poultry feed as a supplement. As suggested by NRC Zinc requirement of poultry is 40 mg/kg of feed.

Environmental Challenges and Zinc

Heat stress can extremely trouble the balance between the generation of reactive oxygen types and the antioxidant system. The oxidative stress result from heat stress led to an increased radical production, which induces oxidative damage and lipid peroxidation to cellular membranes. This leads to physiological changes, including reduced feed intake, decreased metabolic heat production, lower performance in productivity, and a decrease in growth rate and feed efficiency. Zinc supplemented along with Vitamin C has proved to decrease the effect of cold as well as heat stress.

Current Practice

The dietary need for zinc supplementation is well established in poultry feed and is routinely practiced. Earlier depending upon cost and availability zinc supplementation in poultry feed was used at a formulation of Zinc Oxide (ZnO) (72% Zn) and Zinc Sulphate (ZnSO₄H₂O) (36% Zn). The main difference between these source compounds is that most inorganic compounds do not have carbon; however organic compounds always contain carbon and have carbon-hydrogen bonds (C-H).

Most (80-90%) of the supplemental Zn used in poultry diets comes from ZnO source, which is less bioavailable than Zn sulphate for poultry. However, the sulphate (acid salt) is more water soluble, allowing reactive metallic ions to promote free-radical formation. This can support in chemical reactions responsible for the breakdown of vitamins and eventually the destruction of fats and essential oils, down rating the nutritive value of the diets.

Innovation with Nano Zinc

Absorption, Bioavailability, and Efficacy

Nanotechnology has a great potential to be used in poultry production with new tools for the enhancing the ability of poultry to absorb nutrients and therefore improving growth performance, nutrient digestibility, and productive performance of poultry. Nano zinc (ZNOPs) is ultrafine object that behaves as a whole unit in terms of its properties having particle size from 1 to 100 nm. ZNOPs have attracted great attention as an alternative to feed supplements to both organic and inorganic zinc source. In addition, ZONPs have been demonstrated to exert more positive effects, producing better results, due to their novel properties, such as smaller size, increased surface area, a high number of surface-active centres, stronger adsorbing quality, catalytic efficiency, increased bioavailability, absorbability, and exerting a superior efficacy.

Since there are almost unlimited possibilities concerning levels and sources of zinc there is still more research needed. Using zinc as nanoparticles size can be used at lower doses and can provide better result than the conventional zinc sources. Nanoparticles zinc oxide can act as antibacterial agent, modulates the immunity and production of broilers.

Pollution and Zinc

Although currently poultry farmers routinely add Zinc in poultry diet above the NRC recommended level to avoid the possibility of its deficiency, this practise has been linked to environmental pollution since the extra levels of Zn cannot be utilized by crops. With Nano Zinc given the increased bioavailability of organic Zn, it may be possible to supplement this essential element well below the practiced level resulting in less Zn excretion without compromising the performance of the birds and pollution of the environment.

Conclusion

• The prospects of nano zinc in poultry nutrition are indeed profound. With its enhanced absorption, bioavailability, and efficacy, nano zinc stands poised to revolutionize poultry farming practices, enabling producers to achieve optimal growth, immunity, and reproductive performance while minimizing environmental impact.
• As we venture into this era of innovation, the integration of nano zinc into poultry diets holds the potential to redefine standards of excellence in poultry nutrition, ushering in a new era of sustainability and efficiency for the poultry industry.
• In conclusion, the future of poultry nutrition appears promising with the introduction of novel products like CYNKA HBR, (from the R&D platform of Glamac) containing nano zinc solutions. As we continue to explore innovative ways to enhance poultry health and productivity, nano zinc offers a compelling avenue. With its superior bioavailability and potential to address zinc deficiency effectively,
• Nano zinc essential oil complex acts as a gut-acting anti-inflammatory and healing agent, repairing gut villi, and exhibiting antioxidant, antiviral, and antimicrobial properties. CYNKA HBR represents a significant advancement in poultry nutrition. By leveraging nano zinc technology, poultry farmers can optimize the health and performance of their flocks, ultimately contributing to a more sustainable and efficient poultry industry.