Use of a Selected Clay in Growing Pigs Fed Zearalenone Contaminated Sorghum Grain

Certain clays are used as feed additives to decrease the effects of mycotoxins. An experiment was conducted to evaluate the use of a selected clay (Mexsil®) on the prevention of growth depression of growing pigs consuming a grain naturally contaminated and with marginal toxic levels of mycotoxins. One hundred and twenty pigs (30.03 kg avg. initial BW), were allotted to 4 dietary, from outcome groups formed by litter of origin, sex and weight, in a Randomized Complete Block design. Treatments were a 2x2 factorial arrangement: level of zearalenone (ZEA) in sorghum (LOW, 21.6 to 41.6, and HIGH, 111.2 to 146.6 mg/ton) and the addition or not of Mexsil® (Control and 5 kg/ton). Performance was measured during 98 days. As the inclusion of sorghum grain in three feeding phases, as well as the daily feed intake increased, the dose (μg/ kg BW) of ZEA received, went from 1.66 to 0.91 for the LOW and from 5.87 to 2.98 for HIGH, for the feeding phases 1 to 3.

For these reasons, differences in response to the addition of Mexsil® and the level on ZEA were greater during days 0 to 70 of the experiment. No clinical signs of mycotoxicosis were observed. Daily feed intake and feed efficiency were not affected by the level of ZEA (P>0.05), but ADG was lower (P<0.01) for pigs consuming the HIGH level of mycotoxins (755 vs. 837 g). Mexsil® addition improved (P<0.05) ADG (814 vs. 778 g) as was able to maintain gains of pigs consuming ZEA at higher levels. Mexsil® and ZEA did not result in an interaction for any of the response criteria. Use of this clay was effective to improve productive performance of pigs in presence of subclinical levels of ZEA.

Key Words: Zearalenone, Clay, Pigs.