Effects of different dietary inclusions of whole-plant corn silage on growth performance, nutrient availability and jejunal development in growing-finishing pigs

This study aimed to evaluate the effects of whole-plant corn silage (WCS) on growth performance, nutrient availability and intestinal development in growing-finishing pigs. A total of 32 barrows (33.1 ± 3.49 kg) were randomly allocated to four treatments. Control was the basal diet, and the low, medium, and high treatments were basal diets substituted with WCS (air-dry basis) at 5.0%, 7.5%, and 10.0% from day 1 to 42, and 10.0%, 12.5%, and 15.0% from day 43 to 98, respectively. The results showed that the average daily feed intake (ADFI), feed/gain (F/G), and crypt depth (CD) increased linearly (P < 0.05) with the increasing of WCS. However, the final body weight, average daily gain (ADG), biological value (BV), net protein utilization (NPU), dry matter, crude protein (CP), ether extract, crude fibre (CF), and gross energy decreased linearly (P < 0.05). High treatment significantly deteriorated BW, ADG, NPU, and BV compared to control, low, and medium treatments (P < 0.05). The low and medium treatments showed significantly greater ADFI, apparent digestibility (CP and CF), villus height (VH), VH/CD, relative mRNA and protein expression of occludin, claudin-1 and sodium-glucose cotransporter (SGLT1) than the high treatment (P < 0.05). The highest F/G, CD, relative mRNA and protein expression of cationic amino acid transporter (CAT1) were observed in high treatment (P < 0.05). Our results suggested that WCS can replace 7.5% and 12.5% of diet during growing and finishing periods of pigs, respectively. This is of great significance for reducing feeding costs and alleviating food security crises.