Mineral content in browse plants growing at northeastern Mexico

Calcium, K, Mg, Na, P, Cu, Fe, Mn and Zn contents were determined, seasonally, during two consecutive years in leaves of native browse plants such as Castela texana T. & G. Rose (Rutaceae), Celtis pallida Torr. (Ulmaceae), Forestiera angustifolia Torr. (Oleaceae), Lantana macropoda Torr. (Verbenaceae) and Zanthoxylum fagara (L.) Sarg (Rutaceae) growing in rangelands at northeastern Mexico. All minerals, in all species, were significantly different among years, sites and seasons and interactions were also significant. In general, plants in Linares county site, that had the highest rainfall had higher mineral content followed by Los Ramones and China counties; Moreover, during summer all plants had higher mineral content followed by autumn, winter and spring. Regardless of spatio-temporal differences, all plant species had suitable levels of Ca, Mg, K, Cu, Fe and Mn to satisfy range domestic and wild ruminant requirements. Nonetheless, P, Na and Zn showed marginal inadequacies in some seasons throughout the year.