Sulfur concentration in feedlot diets from southeast of Córdoba and Santa Fe provinces

Abstract

In the southeast of Córdoba and southwest of Santa Fe provinces, feedlot cattle (FC) systems have proliferated, with the inclusion of wet corn destillers grains (WCDG) in their diets. According to the background of high concentrations of sulfur(S) in WCDG, and sulfates (SO4 ) excess in drinking water of the region, an excessive dietary S is possible. Productive-health problems have been reported in FC from this region, compatible with those caused by excessive dietary S, associated with WCDG and / or high SO4 drinking water consumption. The objective of the present work was to estimate and evaluate the concentration of total S in the FC diets in this region of Argentina. During the summer and winter of 2017, drinking water samples were collected from 46 farms in order to quantify SO4 concentration and twenty-six WCDG batches from the regional supply plant were sampled for total S determination. The estimation of dietary S concentration was performed for each water well, considering solid food and drinking water contribution. The estimation of S solid food contribution was performed considering the contribution of standard FC diets with 0 (B0), 15 (B15), 30 (B30) and 45% (B45) WCDG inclusion. The average water SO4 concentrations were 196 and 90 mg/l, in the summer and winter samples, respectively. The average WCDG S content was 0.68%. Estimated total dietary S averages in summer were 0,23, 0,29, 0,34 and 0,43% for B0, B15, B30 and B45 diets respectively, while in winter they were 0,22, 0,28, 0,33 and 0,42% for B0, B15, B30 and B45 diets, respectively. In most FC farms from the studied region, it is unlikely that dietary S levels are detrimental to health and productive performance of FC.