EFFECT OF FEED DEPRIVATION TIME ON BACTERIAL CONTAMINATION OF SKIN AND CARCASS IN MEAT GOATS

Abstract

Previous research has shown that diet and feed deprivation time prior to slaughter can influence the fecal shedding of bacteria in goats. This experiment was conducted to determine the effects of feed deprivation time (FDT) on skin and carcass bacterial counts. Thirty-two Boer × Spanish goats (BW = 18.8 ± 0.82 kg) were randomly assigned to one of 4 FDT (0, 9, 18, or 27 h) before slaughter. Immediately after slaughter and evisceration, the pH values of rumen liquor and cecal digesta were determined. Rumen and rectal content samples were collected and transported to the laboratory for culture and determination of microbial load. Initial pH of Longissimus muscle (LM) was determined at 15 min postmortem on each carcass. Swab samples were collected from skin (leg; 25 cm2 area) and carcass (flank, brisket and leg; 75 cm2 area) of each animal to assess the bacterial load. The 27-h FDT group had higher (P < 0.05) rumen pH (6.95) than 0 h (6.23) or 9 h (6.46) FDT groups. Cecal pH was not affected (P > 0.05) by FDT.  The microbial counts of rumen and fecal contents were not influenced by FDT.  The E. coli, total coliform (TCC), and total plate counts of rumen content were 2.93, 3.14, and 6.08 log10CFU/g, respectively, and those of fecal contents were 3.56, 7.25 and 6.81 log10CFU/g, respectively. The FDT had no effect on the initial (pH = 6.87) of LM. The E. coli, TCC, and aerobic plate counts on skin were 1.13, 1.49, and 3.78 log10CFU/cm2, respectively, and those on carcasses were 1.51, 1.65, and 3.11 log10CFU/cm2, respectively. Both skin and carcass microbial counts were not affected (P > 0.05) by FDT. The results indicate that feed deprivation time alone up to 27 h may not significantly influence gut, skin, or carcass microbial loads.