Mineral content of forage species found in sheep farms in the Stateof Yucatán, México

摘要

The purpose of the present study was to diagnose contents of five minerals in forages that grow in sheep farms during the rainy season in the State of Yucatán, Mexico. A total of 50 farms in 47 municipalities were sampled and 88 forage samples were gathered. Ca, K, Fe, Cu and Zn contents were determined through atomic absorption spectrophotometry and average content and dispersion parameters were estimated. Results were analyzed using a General Linear Model to detect effects of sampling area (Center, East, South, West), soil type (Rendzina, Litosol, Luvisol, Vertisol, Cambisol), forage type, interactions and experimental error. Average results obtained were 0.53+-0.41 % Ca, 0.51+-0.24 % K, 12.8+-10.1 % Cu, 251 + -149 ppm Fe and 27.6+-12.6 ppm Zn. Nutrient content adequacy for 40 kg single lamb lactating ewes was 34, 48, 27.8 and 57.7 % for Ca, K, Cu and Zn, respectively. Practically no deficiencies were found for Fe. Both Ca and Zn content was greater (P<0.05) in East and West areas. Soil type effect was only found in Cambisols, which showed a greater Cu content (P<0.05). Rangeland forage showed the higher Ca, K, Cu and Zn content (P<0.05). It can be concluded that nutrient inadequacies were found for Ca, K, Cu and Zn, while Fe showed high levels. Formulation and manufacture of mineral supplements meant for sheep in Yucatan should include these minerals and be Fe free.