Effects of Supplemental Feeding of Plum Juice Concentrate on Fecal Microbial Shedding and Pork Quality

Abstract

Purebred Yorkshire pigs (n=32) were fed at the Auburn University Swine Research and Education Center to determine the influence of supplementation of plum juice concentrate (PJC) on microbial shedding, growth, carcass, and quality characteristics of pork. Pigs were sorted by weight and sex (n=16 barrows, n=16 gilts) and assigned to a pen which housed two pigs per pen. Pens were randomly allotted to one of four treatment groups. Experimental diets contained 0% (Control), 0.5%, 1%, or 2.9% plum juice concentrate (PJC). All basal diets consisted of corn and soybean meal formulated to meet or exceed National Research Council (NRC) recommendations. Pigs were allowed ad libitum access to feed and water, and treatment diets were formulated to be isocaloric. During the feed trial, feed intake and weight gain were measured every 14 d and fecal samples were collected directly from the anus from one pig per pen on days 0, 1, 7, 14, 28, 56, and last day on feed(Group 1=84 d; Group 2=100 d). Pigs were harvested (n=2 groups) at an average pen weight of 114 kg. All pigs were swabbed near the anus to measure microbial load on the hide. Fecal and ham swab samples were plated and enumerated for anaerobic bacteria (AA) and aerobic bacteria (APC). Samples were also enriched to determine prevalence of Salmonella spp. and generic E.coli (VRBA). Carcass and quality characteristics were recorded according to National Pork Producers Council Guidelines (2000) 24 hr postmortem. Data were analyzed using GLM procedure and mixed model analysis (SAS, 2002). Pen was the experimental unit and independent fixed effects included: diet, sex, rep, and harvest group for growth, carcass, and meat quality. Diet and day were independent fixed effects for microbial analysis. Results indicated that Salmonella spp. was not present in any sample throughout the experiment, therefore no data are reported. Total counts for anaerobic bacteria and E.coli were not different among any treatment. Feeding PJC was effective in decreasing fecal bacterial populations for APC (P=0.03) when compared to the control. Additionally, AA (P=0.04) bacteria counts were different for day by treatment effect and showed a decreasing trend for treatments 1.0% PJC and 2.9% PJC. The level of PJC did not affect growth performance or meat quality. Wetness was the only carcass characteristic to be affected by level of PJC supplement (P=0.02), The results of this study demonstrate that supplementing a PJC to growing / finishing pigs does decrease aerobic bacteria as well as decreases anaerobic, aerobic and VRBA counts from d 0 to d 14. However, these results indicate that the supplementation of PJC has no effect on growth, carcass, or quality characteristics of pork.