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Many animal feed grains contain highβ-glucan in the cel wal . Pigs do not secretβ-glucanase to degrade theβ-glucan in their feed. The indigestibleβ-glucan not only blocks the release of nutrients from the grain cel wal , but also increases the digesta viscosity in the gastrointestinal tract of pigs. Therefore, dietaryβ-glucan signiifcantly inhibits nutrient digestion and absorption in pigs. Transgenic expression ofβ-glucanase in the digestive tract of pigs may offer a solution to solve this problem. In the current study, four artiifcial codon-optimizedβ-glucanases genes was prepared and expressed in porcine cel s. Only pBgA and pEgx showed high activity in transfected pig kidney cel s. To improve the pH range and pH stability ofβ-glucanase, the twoβ-glucanases, pBgA and pEgx, were co-expressed in pig kidney cel s and salivary gland cel s by Linker A3 or 2A peptide. The resulting dual enzymes of pBgA3pEg and pBg2ApEg showed signiifcantly enlarged pH range and signiifcantly increased pH stability, as compared to parental enzymes. These results provide useful data for future study on increasing the feed digestibility of pigs by transgenic expression ofβ-glucanase in their salivary glands.