GROWTH AND METABOLIC PARAMETERS IN STEERS FED HIGH LEVELS OF SODIUM CHLORIDE AND LIMESTONE

Abstract

Sixty-four yearling steers were fed a fattening diet plus 0.5% NaCl (control), 2% limestone, 5% NaCl, or 5% NaCl plus 2% limestone. Feeding 5% NaCl and 5% NaCl plus 2% limestone resulted in decreased total gain (P < 0.01), average daily gain (P < 0.01) and carcass weight (P < 0.05) while 5% NaCl decreased the efficiency of organic matter utilization (P < 0.05). Sodium chloride supplementation decreased ruminal pH and acetate to propionate ratio at day 62 but there was no effect of NaCl evident in samples collected on day 118. Blood glucose was decreased (P < 0.05) at days 62 and 118 in steers fed 5% NaCl and 5% NaCl plus 2% limestone. Supplementation with high levels of sodium chloride nonsignificantly increased the percentage of starch in cecal and colon digesta samples collected at slaughter. Also the NaCl treatment decreased pH (P < 0.05) in the colon and acetate to propionate ratio (P < 0.10) in the cecum. Although NaCl supplementation altered ruminal and digestive parameters, it did not result in increased performance. Key words: Sodium chloride, limestone, beef cattle, growth