Morphological and biochemical blood parameters in broilers at correction with dietary copper salts and nanoparticles

Diets of modern crosses and breeds of farm animals require mandatory correction of mineral nutrition. Ionic forms commonly used for correction are characterized by low bioavailability, prooxidant effect, and high toxicity in vivo. That is why low-toxic sources of essential chemical elements are of particular interest, including nanocrystalline metals. We firstly assessed the efficient of nanosized copper on the model of broiler chickens. A comparative study of productive and biological effects of copper nanoparticles (CuNPs) and сopper sulfate was carried out on Smena 7 chickens of 14-42 days of age using different administration methods. Hematologic and biochemical parameters and elemental composition of tissues were assessed. We revealed an increase in red blood cells and hemoglobin and decrease of platelets at the highest doses of Cu NPs administrated orally or intramuscularly. The biochemical blood parameters assessed indicated an enhancement of plastic processes in the body and, as a consequence, an increase in the growth rate under Cu NPs administration. The difference of the total protein compared to the control (33.6 %, p < 0.05) was the highest when Cu NPs injected at a dose of 2 mg/kg which increased the supply of protein synthesis. The albumin level was higher in 28-day old chicks injected with Cu NPs (2 and 0.2 mg/kg). A replacement of dietary CuSO4 with dietary Cu NPs led to an increase in the growth rate. When Cu NPs fed, the found biochemical parameters indicated strengthening of energy and synthetic processes in the body, and therefore, an increase in the poultry growth. At 1.7 mg/kg of dietary Cu NPs the gained weight was 13.5-23.8 % (p < 0.01 to p < 0.001) more as compared to the control. Dietary Cu NPs at 0.7 mg/kg was not enough to highly stimulate the poultry growth and resulted in the weight gain which was lower than in the poultry fed with Cu NPs at 1.7 mg/kg but higher (by 8.5-18.4 %, p < 0.01 to p < 0.01) as compared to the poultry not fed with Cu NPs. Thus, the promoting effect depends on the form of copper source. The Cu NPs effectiveness under enteral administration at 1.7 mg/kg or intramuscular double injections at 0.2 mg/kg was superior to that of dietary copper sulfate.