Effects of copper hydroxychloride and dietary fiber on intestinal permeability, growth performance, and blood characteristics of nursery pigs

Abstract

Two experiments were conducted to test the hypothesis that copper (Cu) hydroxychloride improves growth performance and blood characteristics, and reduces intestinal permeability of nursery pigs fed diets without or with inclusion of cereal co-products. In experiment 1, 32 pigs (13.53 ± 1.27 kg) were allotted to a 2 × 2 factorial arrangement with 2 types of diets (low-fiber or high-fiber) and 2 levels of Cu from Cu hydroxychloride (0 or 150 mg/kg). Pigs were adapted to diets for 5 days, followed by the oral administration of lactulose and mannitol on day 6. After administration, urine was collected during two 6 -h periods. Results indicated that pigs fed high-fiber diets tended to have greater (P < 0.10) urinary lactulose:mannitol ratio during the first 6 -h period, whereas dietary Cu concentrations did not affect lactulose:mannitol ratios of pigs. In experiment 2, 128 pigs (8.33 ± 1.32 kg) were allotted to the same dietary treatments as in experiment 1 and used in a 21-day growth assay. There were 4 pigs per pen and 8 replicate pens per diet. On day 7, day 14, and on day 21, blood samples were collected from 1 pig per pen and tumor necrosis factor-α, immunoglobulin G, interleukin-1 ß, interleukin-10 (IL-10), blood urea nitrogen (BUN), total protein, and albumin were analyzed. Results indicated that there were no interactions between diet type and Cu hydroxychloride for overall growth performance and blood characteristics of pigs. Overall average daily gain and gain:feed were greater (P < 0.05) for pigs fed diets containing Cu hydroxychloride compared with pigs fed diets without Cu hydroxychloride. The level of dietary fiber did not affect overall growth performance of pigs. However, BUN concentration tended to increase (P < 0.10), and a reduction (P < 0.05) in albumin and IL-10 concentrations on day 14 was observed for pigs fed high-fiber diets compared with pigs fed low-fiber diets. Supplementation of Cu hydroxychloride to diets positively influenced (P < 0.05) BUN, albumin, and cytokine concentrations of nursery pigs. In conclusion, supplementation of Cu hydroxychloride to low-fiber or high-fiber diets improved growth performance and some blood characteristics in nursery pigs.