In Vitro and In Vivo Assessment of Dietary Supplementation of Both Natural or Nano-Zeolite in Goat Diets: Effects on Ruminal Fermentation and Nutrients Digestibility

Abstract

This study aimed to evaluate <i>in vitro</i> and <i>in vivo</i> dietary supplementation with different levels of natural or nano-zeolite forms on rumen fermentation patterns and nutrient digestibility. In the <i>in vitro</i> experiment, a basal diet (50% concentrate: 50% forage) was incubated without additives (control) and with natural zeolite (10, 20, 30 g/kg DM) or nano-zeolite (0.2, 0.3, 0.4, 0.5, 1.0 g/kg DM) for 24 h to assess their effect on ruminal fermentation, feed degradability, and gas and methane production using a semi-automatic system of <i>in vitro</i> gas production (GP). The most effective doses obtained from the <i>in vitro</i> experiment were evaluated <i>in vivo</i> using 30 Barki goats (26 ± 0.9 SE kg body weight). Goats were allocated into three dietary treatments (<i>n</i> = 10/treatment) as follows: control (basal diet without any supplementations), natural zeolite (20 g/kg DM diet), and nano-zeolite (0.40 g/kg DM diet). The <i>in vitro</i> results revealed that only the nano-zeolite supplementation form quadratically (<i>p</i><i>=</i> 0.004) increased GP, and the level of 0.5 g/kg DM had the highest GP value compared to the control. Both zeolite forms affected the CH₄ production, linear, and quadratic reductions (<i>p</i> < 0.05) in CH₄ (mL/g DM), consistent with linear increases in truly degraded organic matter (TDOM) (<i>p</i> = 0.09), and propionate molar proportions (<i>p</i> = 0.007) were observed by nano zeolite treatment, while the natural form of zeolite resulted in a linear CH₄ reduction consistent with a linear decrease (<i>p</i> = 0.004) in NH₃-N, linear increases in TDOM (<i>p</i> = 0.09), and propionate molar proportions (<i>p</i> = 0.004). Results of the <i>in vivo</i> experiment demonstrated that the nutrient digestibility was similar among all treatments. Nano zeolite enhanced (<i>p</i> < 0.05) the total short-chain fatty acids and butyrate concentrations, while both zeolite forms decreased (<i>p</i> < 0.001) NH₃-N compared to the control. These results suggested that both zeolite supplementation forms favorably modified the rumen fermentation in different patterns.