The objective of the study was to determine if Escherichia coli (E. coli) or Staphylococcus aureus (S. aureus) on the skin contaminates acupuncture (AP) and hypodermic needles during routine AP and aqua-acupuncture (Aqua-AP). The in-vitro study design on samples from 4 deceased cows, consisted of 8 experimental protocols (Groups 1-8). In Groups 1-4, E. coli or S. aureus was applied to skin with or without alcohol and the needle was then inserted into skin and muscle, withdrawn and cultured. In Groups 5-8, the needle was inserted through skin only and directly into the culture broth with bacteria added to the skin surface (Groups 5 and 6) and on wet or dry skin with no bacteria added (Groups 7 and 8). Testing in each group was repeated 5 times and the numbers of positive bacterial cultures were counted. Based on the results of this pilot study some recommendations might be considered: 1) swabbing acupoint sites with alcohol prior to AP is probably unnecessary, if a sterile disposible AP needle is inserted through dry, clean, normal skin, 2) in debilitated or immune compromised animals or when skin and hair contamination are suspected, acupoint sites should be swabbed with alcohol prior to needle insertion, 3) hypodermic needles should not be substituted for AP needles, 3) During Aqua-AP re-insertion of the same needle at multiple sites should be avoided, as the risk of secondary infection is high, 4) Wet skin may increase the risk of infection during Aqua-AP.