Effect of saponite (EcoMix) on toxin binding capacity, ruminal fermentation, diet digestibility and growth of steers fed high concentrate diets

• Published in: Journal of animal science 2016-10, Vol.94, p.652-652
• Main Authors: Lancaster, N A, Antonelo, D Silva, Muegge, C R, Schoonmaker, J P
• Format: Article
• Language: English
• Subjects: Acetic acid; Aflatoxin B1; Binding; Clay minerals; Diet; Digestibility; Effects; Enzymatic activity; Enzyme activity; Ergotamine; Fermentation; Lactic acid; Minerals; Organic matter; Performance enhancement; pH effects; Propionic acid; Proteins; Saponite; Studies; Toxins; Urine
• ISSN: 0021-8812; 1525-3163
• DOI: 10.2527/jam2016-1349

Three experiments were conducted to determine the effect of increasing concentrations of the clay mineral, saponite (Eco- Mix, United Minerals Group), on toxin binding, ruminal fermentation, diet digestibility and growth of feedlot cattle. In experiment one, 150 mg of EcoMix was incubated in 10 mL of rumen fluid with 3 incremental concentrations of aflatoxin B1 (AFB1) or ergotamine tartate (ET) to determine binding capacity. In experiment two, 6 steers (initial BW = 596 ±22.2 kg) were randomly allotted to 3 treatments in a replicated 3 x 3 Latin square design (21-d periods) to determine the effects of increasing amounts of EcoMix (0, 1, or 2%) on ruminal pH, VFA, and nutrient digestibility. EcoMix was top-dressed on an 80% concentrate diet at a rate of 0, 113, or 226 g/steer/d to achieve the 0, 1, and 2% treatments, respectively. In experiment three, 72 Angus x Simmental steers were blocked by BW (395 ± 9.9 kg) and allotted to the same 3 treatments (4 pens/treatment, 6 steers/pen) to determine the effects of EcoMix on performance. Steers were slaughtered at a target BW of 606 kg. EcoMix was able to effectively bind AFB1 and ET at concentrations well above the normal physiological range (52 and 520 μx|Ý|/x|g/mL), but % adsorption was decreased to 35.5 and 91.1% at 5200 μx|Ý|/x|g/mL (P < 0.0001) for AFB1 and ET, respectively. EcoMix linearly decreased ruminal lactate and propionate, and VFA production efficiency (P ≤ 0.04), linearly increased formate and acetate:propionate (P ≤ 0.03), and tended (P = 0.07) to linearly increase butyrate. EcoMix tended to linearly increase organic matter and crude protein apparent digestibility (P = 0.06). Ruminal pH, urine pH, and other digestibility measures did not differ among treatments (P ≥ 0.15). During the first month there was a quadratic response of EcoMix on ADG (P = 0.009) and gain:feed (P = 0.0003), increasing from 0 to 1% EcoMix, and then decreasing from 1 to 2% EcoMix. However, during the second month, EcoMix decreased ADG and gain:feed linearly (P ≤ 0.03) and overall ADG, DMI, or gain:feed were not impacted (P ≥ 0.46). EcoMix linearly decreased marbling score (P = 0.05). Hepatic enzyme activity did not differ among treatments on d 0 or at slaughter (P ≥ 0.15). In conclusion, EcoMix effectively binds ruminal toxins, decreases ruminal lactate, and improves performance during adaptation to a high concentrate feedlot diet.