Effects of Dietary Copper on Ruminal Fermentation, Nutrient Digestibility and Fibre Characteristics in Cashmere Goats

Abstract

Thirty-six 1.5 year-old Inner Mongolian White Cashmere wether goats (body weight 28.14±1.33 kg) were used to determine the effects of dietary copper (Cu) concentration on ruminal fermentation, nutrient digestibility and cashmere fibre characteristics. Wethers were fed a basal diet (containing 7.46 mg Cu/kg DM) that was supplemented with either 0 (control), 10, 20 or 30 mg Cu/kg DM. To ensure full consumption, animals were fed restrictedly with 0.75 kg feed (DM) in two equal allotments per day. The results indicated that: (1) supplemental 10 mg Cu/kg DM in the basal diet significantly (p 0.05); however, NDF digestibility of groups supplemented with 10 and 20 mg Cu/kg DM were significantly higher than that of the control group (p 0.05). In conclusion, supplementation of cashmere goats with Cu at the rate of 10 to 20 mg/kg DM in the basal diet resulted in some changed rumen fermentation and was beneficial for NDF digestibility, while supplementation of 20 mg Cu/kg DM improved cashmere growth. Collectively, the optimal supplemental Cu level for cashmere goats during the fibre growing period was 20 mg/kg DM (a total dietary Cu level of 27.46 mg/kg DM).