Fortier, M. P., Saucier, L. and Guay, F. 2012. Effects on microbial quality of fresh pork loin during storage from oregano oil and cranberry pulp diet supplementation in pigs. Can. J. Anim. Sci. 92: 465-471. Oregano oil and ground cranberry pulp supplements were added to the diets of finishing pigs to determine their antimicrobial effects on fresh loin during storage at 2±1°C. Two doses of oil (250 and 500 mg kg^-1) and three doses of cranberry (5, 10 and 20 g kg^-1) were tested according to a factorial experimental design. The control group did not receive any supplements. The meat was vacuum packed and analyzed after 0, 23, 45 and 60 d. Samples were re-packaged under aerobic conditions after 0 or 23 d and analyzed after 4, 8 and 12 d. Microbial analysis was performed periodically throughout the experiment. Initial cell counts were below detection level for total aerobic mesophilic (TAM) (<10² cfu g^-1), Pseudomonas spp. (<10² cfu g^-1), presumptive lactic acid bacteria (LAB) (<10² cfu g^-1), and Escherichia coli and coliform counts (<10¹ cfu g^-1). No significant difference in TAM counts was observed between all of the six different treatments and the control group except for samples packaged at day 0 under aerobic conditions after 12 d of storage where a significant effect of the supplementation was observed (P<0.03). Under anaerobic conditions, LAB were not affected and remained the predominant microflora despite antimicrobial treatments.