The Effects of Zinc Oxide Nano Particles on Growth Performance and Blood Metabolites and some Serum Enzymes in Holstein Suckling Calves

The second element trace mineral in the body, which is stored in the body as well as regulator feed intake. In many of the vital functions of the body, including growth, building hormones, vitamins and enzymes plays a role and where involved is necessary in animal diets. Because the animal's body cannot take much more of this element in the body thereby providing a daily basis through the diet can be effective. Also, the most common combination of zinc element is its oxide form (ZnO), which is preferred for two reasons, one that has the highest concentration of zinc, and the other is that it is absorbed high in the body and is also better tolerated by the target tissues. Recently, Nano-zinc oxide has attracted much attention in animal nutrition studies. Different nanoparticles are new forms of materials with high biologic properties and low toxicity, which seem to have high potential for passing through physiological barriers and access to specific target tissues. The use of antioxidants, such as Nano-zinc oxide, can be important in reducing the production of free radicals. The aim of this study was to evaluate the effect of nano-zinc oxide on performance, growth and blood parameters in Holstein suckling calves.
The Zinc Oxide nanoparticles were purchased from Iranian agent of US Research Nanomaterial, Inc. Port Co., Ltd., USA. The sizes of elemental ZnO particles ranged from 10 to 30 nm, stock: US3590, in the form of white powder and Purity: 99%, APS: 10-30 nm, Color: white, Crystal Phase: single crystal, Morphology: nearly spherical, SSA: 20-60 m2/g, True Density: 5.606 g/cm3. In this study 24 Holstein calves with a mean age of 1 - 10 and an average weight of 38±2 were selected from pars Agro-Industrial and Animal Husbandry dairy herd to determine the effects of supplementation nano-zinc oxide on performance, blood parameters and some serum enzymes of them. Three levels 0 (control), 30 and 60 of the Nano-zinc oxide were added to the calves starter concentrate as mg / kg of dry matter. Calves were allotted to the experimental groups randomly and based on their age and weight to have similar age and weight average among the group. The calves were housed in individual pens and fed with whole milk approximately at 10% of birth weight and they had free access to the feed starter and water. Milk was offered in two equal meals daily at 08:00 and 19:00. Blood samples were collected from the jugular vein on the 30 and 70 day of the trial (4 h after the morning feeding) by heparinised venoject tubes, centrifuged at 3500 rpm for 15 min at 4 °C, and collected plasma was immediately transported to the laboratory and frozen at −20 °C until analysis. Blood concentrations of glucose, cholesterol, triglyceride, albumin, urea, alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, globulin and total antioxidant activity, glutathione peroxidase, catalase were measured using the commercial kits. Data were analyzed in a completely randomized design using the MIXED procedure of SAS. For variables measured over time (average daily gain, dry matter intake, and feed conversion ratio), time was added to the model as a repeated factor.
The results showed that the use of different levels Nano-zinc oxide had no significant effect on feed intake and feed conversion ratio, whereas on the experimental diet supplement Nano-zinc oxide suckling calves did show significant effect on final weight, weight gain. The significant difference was not observed between the concentration of blood parameters (glucose, cholesterol, triglyceride, albumin, urea, alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, globulin and total antioxidant activity, glutathione peroxidase, catalase except superoxide dismutase). The results showed that supplementing with 60 ppm Nano-zinc oxide significant was increased in the concentration or activity of blood superoxide dismutase compared to the control group. Dietary nano-zinc oxide supplementation on Holstein calves compared to the control group increased concentrations of superoxide dismutase. Zinc-dependent antioxidant enzymes such as superoxide dismutase reduces the activity of this enzyme in the membrane of cells, including red blood cells, leading to increased damage of oxidative stress.
The results of this study showed that supplementation of Nano-zinc oxide in the diet improved the body weight, daily gain and superoxide dismutase concentration in Holstein suckling calf. In general it can be concluded that the use of zinc to form nanoparticles had no effect on performance and blood parameters. Thus, nano-zinc oxide supplementation in suckling calf starter diet can effectively help to cope with the stress.