The effects of hydrated sodium calcium aluminosilicate on fescue toxicosis

Three trials were conducted to determine whether hydrated sodium calcium aluminosilicate (HSCAS) will alleviate fescue toxicosis or affect mineral metabolism. In the first of two in vitro experiments, buffered solutions indicated that ergotamine will bind with HSCAS at pH levels of pH 7.8 or less. In the second in vitro experiment, when timothy hay was the substrate incubated in ruminal fluid, recoveries of ergotamine were lower than in the first in vitro experiment which utilized buffer solutions. This suggests that feed or microbial particles adsorbed ergotamine. During in vitro post-ruminal digestion with acid-pepsin, more ergotamine was recovered from precipitated pellets when they contained HSCAS than when they did not, indicating adsorption of ergotamine to HSCAS.

A rat growth study was conducted to determine whether signs of fescue toxicosis could be reduced by the addition of HSCAS to diets containing Acremonium coenophialum infested (E+) fescue seed. Inclusion of HSCAS in diets did not appear to reduce signs of fescue toxicosis. Rats fed diets containing E+ seed consumed less feed, gained less weight and had lower gain per unit of feed than did those consuming diets containing noninfested (E-) seed. Serum prolactin concentrations (PRL) and testes weights tended to be lower in rats receiving E+ diets than in rats pair-fed E- diets.

A sheep metabolism trial was conducted to determine whether 2% dietary supplementation of HSCAS alleviated signs of fescue toxicosis and whether HSCAS interfered with mineral utilization. Serum sorbitol dehydrogenase activity suggested that HSCAS could help prevent hepatic cell destruction associated with consumption of E+ fescue. Ruminal pH and concentrations of ruminal volatile fatty acid concentrations (VFA) and ammonia were similar among treatments. Sheep consuming HSCAS also had lower apparent absorptions of Mg, Mn and Zn than those not receiving HSCAS. Animals supplemented with HSCAS may need additional mineral supplementation with Mg, Mn and Zn.