Effects of raw and heated palygorskite on rumen fermentation in vitro

• Published in: Applied clay science Vol. 138; pp. 125 - 130
• Main Authors: Zeng, H.F., Lin, L.J., Xi, Y.M., Han, Z.Y.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.03.2017
• Subjects: Dairy cow; Heat treatment; In vitro; Palygorskite; Rumen fermentation; Dairy cow; Heat treatment; Rumen fermentation; Palygorskite; In vitro
• ISSN: 0169-1317; 1872-9053
• DOI: 10.1016/j.clay.2017.01.006

To investigate the effect of raw and heated palygorskite on rumen fermentation in an in vitro gas-production system, 54 incubators were evenly divided into three groups: control (0% palygorskite), treatment I (3% raw palygorskite) and treatment II (3% heated palygorskite). The effect of heated modification on the microstructure of palygorskite was investigated by X-ray diffraction and scanning electron microscopy analyses. The physicochemical features were evaluated by zeta potential analysis, cation-exchange capacity, ethylene blue absorption and specific surface area (the BET method). Gas production (GP) was recorded at 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22 and 24h of incubation in vitro. The 18 incubators from each group were stopped at 6h, 12h and 24h, respectively, and the inoculants were determined for rumen fermentation parameters. The results showed that the GP in the treatment groups was higher than in the control group starting at 4h of incubation (P<0.05). Compared with the controls, adding raw palygorskite increased the concentrations of acetate and total volatile fatty acids (TVFAs) at 6h (P<0.05). Adding heated palygorskite increased the concentrations of acetate at 6h and 24h (P<0.05), of propionate at 12h (P<0.05), of acetate/propionate (A/P) at 6h (P<0.05) and of TVFAs at 6h and 24h (P<0.05). The concentrations of lactic acid in the treatment groups were lower than in the control group at 12h (P<0.05), while pH was higher at 12h and 24h (P<0.05, range 6–7). The concentration of NH3-N in the treatment I group was higher than in the control group at 24h (P<0.01), while in the treatment II group, it was higher at 12 and 24h (P<0.05). The results indicated that supplemental raw and heated palygorskite could improve rumen microbial fermentation, promote VFA formation and nitrogen use, especially when adding heated palygorskite. •The thermal treatment process does not evidently damage the crystal structure of palygorskite.•The adsorption capacity of heated palygorskite was increased.•Supplemental raw and heated palygorskite improve rumen microbial fermentation.•Supplemental palygorskite promotes VFA formation and nitrogen use, especially heated palygorskite.•Supplemental raw and heated palygorskite affect rumen pH value.