Abstract
This study aimed to prepare a complex of montmorillonite (MMT) intercalated with porcine glucagon-like peptide (pGLP-2) and evaluate its therapeutic effects in weaning piglets challenged with lipopolysaccharide (LPS). Forty-eight 28-day-old weaning pigs with an average body weight (BW) of 8.47 kg were divided into two groups: a control group fed a basal diet and an MMT/pGLP-2 group fed a basal diet supplemented with 0.5‰ MMT/pGLP-2 complex. At the end of the experiment, 12 piglets from each group were intraperitoneally administered LPS (100 g/kg BW) or saline. The results demonstrated that at pH 3.4, 98.67% of pGLP-2 was adsorbed onto MMT. At pH 9.0 and 7.5, the desorption rates of pGLP-2 were approximately 40% and 26%, respectively, which were significantly greater than those at pH 5.0 or 2.0 (less than 1%). Desorption reached equilibrium within 0.5 h. The interlayer spacing of MMT increased from 1.28 nm to 1.49 nm after pGLP-2 adsorption. Compared to the control diet, the MMT/pGLP-2-supplemented diet significantly (P < 0.05) enhanced maltase, lactase, and Na+-K+-ATPase activities in the jejunum and ileum and sucrose activity in the jejunum. The lengths and weights of the jejunum and ileum were significantly greater in the MMT/pGLP-2 group (P > 0.05). No significant differences (P > 0.05) were observed in body weight, average daily gain, average daily feed intake, or feed-to-gain ratio among the groups. Under LPS challenge, piglets supplemented with MMT/pGLP-2 exhibited significant increases (P < 0.05) in maltase, sucrose, and Na+-K+-ATPase activities in the jejunum and ileum and lactase activity in the jejunum compared to those in piglets administered saline. These findings suggest that the MMT/pGLP-2 complex, prepared under acidic conditions and releasing pGLP-2 under basic conditions, can mitigate intestinal injury from LPS and restore intestinal function, making it a potential feed additive for piglets.