Nano-Molybdenum and Macleaya cordata Extracts Improved Antioxidant Capacity of Grazing Nanjiang Brown Goats on Copper and Cadmium-Contaminated Prairies

Abstract

To investigate the effects of nano-ammonium octamolybdate (nano-Mo) and Macleaya cordata extracts (MCE) on antioxidant capacity of grazing Nanjiang brown goats on natural prairies under Cu and Cd stress, a 2 × 2 factorial design was adopted in this test, and two factors were nano-Mo (0, 10 mg/kg) and MCE (0, 3000 mg/kg). 24 hm² polluted grassland was used in this 30-day trial and was equally divided into twelve fenced units. A total of 36 Nanjiang brown goats (1 year old) with an average body weight (BW) of 40.9 ± 2.1 kg were used in this test. The dietary treatments were (1) CON group, basic diet; (2) Nano-Mo group, basic diet + 10 mg/kg added Mo (nano-Mo); (3) MCE group, basic diet + 3000 mg/kg added MCE; and (4) combined group, basic diet + 10 mg/kg added nano-Mo and 3000 mg/kg added MCE. Nano-Mo or combination of nano-Mo and MCE diets significantly decreased the Cu content in serum and the liver of grazing goats (P < 0.05) and increased the Fe and Mo contents in serum and the liver (P < 0.05). The supplementation of nano-Mo, MCE, and combined diets extremely increased the levels of blood Hb, RBC, and PCV (P < 0.05), as well as the activities of serum SOD, GSH-Px, CAT, and Cp (P < 0.05), and greatly decreased the blood WBC content (P < 0.05) and the serum MDA content (P < 0.05). In conclusion, the application of nano-Mo and/or MCE diets on contaminated grasslands changed the contents of mineral elements in serum and the liver of grazing goats, reduced oxidative stress, and improved antioxidant capacity. The combination of nano-Mo and MCE can alleviate the toxic damage of combined heavy metal contaminations.

Keywords: Copper and cadmium contamination; Macleaya cordata extract; Nanjiang brown goat; Nano-molybdenum.