Resumen

APARICIO, Rafael et al. Parenteral supplementation with copper on the weight of calves in growth. Zootecnia Trop. [online]. 2007, vol.25, n.3, pp.221-224. ISSN 0798-7269.

ABSTRACT     Between May 2005 to November 2006, it was evaluated the effect of the supplementation with injected copper (Cu) on the weight gain of 42 growing Brahman calves fed on natural pastures. Animals were distributed in three groups of 14 to which the following treatments were applied: T1: no supplementation (control), T2: subcutaneous injection of 25 mg of Cu, and T3: subcutaneous injection of 50 mg of Cu. The applied Cu was based on glicinate of copper, gluconate of copper, lactobionate of copper and octadecanoate of copper, administered every two months. The concentration of phosphorus and copper were deficient, so much in forages as water of the watering places, whereas calcium was within the normal range, being high iron, manganese, and zinc concentrations. The treatments T2 and T2 parenteral with Cu increased significantly the weight of the calves in 19 and 15%, respectively, compared to those without Cu.  Nevertheless, more information is needed to give recommendations on the age of the suplementación

Palabras clave : Copper; supplementation; calves; weight gain.