16S analysis of fecal microbial communities of Simmental crossbred cattle
otal genomic DNA from feces was extracted using the cetyltrimethylammonium bromide/sodium dodecyl sulfate method. The DNA samples were tested for integrity using 1% agarose gel electrophoresis and their concentration was determined using a Qubit fluorometer (Invitrogen, Carlsbad, CA, USA). According to the concentration, DNA was diluted to 1 ng/L using sterile water. The V3V4 regions of the 16S ribosomal DNA (rDNA) genes were amplified by polymerase chain reaction.