Bioavailability of dietary copper and zinc proteinates and sulphates in adult Texel sheep

Mineral deficiencies for livestock are reported from almost all world regions. Deficiency can be caused by inadequate intake or by the presence of antagonists in the diet. Traditionally, inorganic salts, such as oxides and sulphates have been added to the diet to meet the requirements of the animal. More recently, there has been increasing interest in mineral chelates. Studies by Rojas et al. (1995) and Ward et al. (1996) have reported that the copper and zinc availability in copper and zinc chelates is greater than in the traditional inorganic salts. Other studies by Kegley et al. (1994) and Schell et al. (1996) reported contradictory results. In this study, two separate trials were carried out to compare the effects of Bioplex copper and Bioplex zinc with the effects of copper and zinc sulphate on plasma copper and zinc levels in adult Texel sheep.