Interaction of copper source, bile composition on microbial growth, and Cu protein homeostasis

摘要

One hundred twenty weaned nursery pigs (6.12 +/- 0.56 kg) were utilized in this experiment to determine the effects of Cu concentration and source on performance, bile components, Cu metabolism, and gastrointestinal microbial distribution in nursery pigs blocked by weight and gender and placed in pens containing 5 pigs of similar weight distribution per pen. Pigs were fed one of four dietary treatments for 21 or 22d. Treatments consisted of: (1) Control (5 mg of Cu/kg from CuSO4); (2) 250 mg of Cu/kg from CuSO4, (250-sulfate) (3) 75 mg of Cu/kg from Cu-MINTREXRTMCu (75-Min; Novus International, Inc., St. Charles, MO), and (4) 75 mg of Cu/kg from CuSO4 (75-sulfate). On d 22 and 23, equal numbers of pigs per treatment were slaughtered. Post slaughter, blood, liver, intestinal tissue and contents, and bile samples were obtained. Body weights, ADG, and ADFI were similar across treatments (P > 0.20). Feed efficiency was greater (P < 0.05) for pigs receiving 250-sulfate compared to controls (0.53 vs. 0.43 +/- 0.03, respectively), and pigs fed 75-Min (0.47 +/- 0.03) or 75-sulfate (0.44 +/- 0.03) were intermediate. Pigs receiving 250-sulfate had greater (P < 0.05) bile (7.05 vs. 2.06 +/- 0.49; respectively) and liver (124.4 vs. 53.3. +/- 24.6, respectively) Cu concentrations than controls. Bile components, intestinal bacterial populations, and small intestine gene expression profiles (Ctr-1, Atox-1, Cox-17, ATP7a, and ATP7b) associated with Cu absorption and homeostasis were similar across treatments (P > 0.20). Antimicrobial effects of bile (determined by measuring the diameter of the zone of inhibition; mm) tended (P < 0.20) to be higher for 250-sulfate and 75-Min treatments compared to controls. Data from this experiment indicated that Cu dose influenced pig performance, but dose or source did not influence measured bile components, intestinal bacterial populations, or intestinal gene expression profiles associated with Cu absorption.