Project Number: 5442-32000-014-06
Project Type: Specific Cooperative Agreement

Start Date: Dec 15, 2011
End Date: Jan 30, 2013

Objective:
The ultimate objective of this research is to provide pork producers with practical treatment and withdrawal guidelines for the use of penicillin G procaine in sows. Specific objectives are to: 1) provide the pork industry guidelines on appropriate patterns of intramuscular delivery of penicillin G procaine to sows; 2) provide the pork industry with appropriate withdrawal periods for sows treated with penicillin G procaine under treatment conditions typically recommended by veterinarians; and 3) to determine the incidence of "false-positives" returned by the "Charm-KIS" microbial inhibition test under controlled conditions.

Approach:
Heavy sows (>400 lb) will be treated with a 5x penicillin G procaine dose via intramuscular administration on 3 consecutive days. Three patterns of drug administration will be provided to three separate groups of sows: Treatment 1: A maximum injection volume of 10 mL will be administered to sows, but within day, multiple injections will be made into a single muscle group to deliver the total required drug volume (5 mL/100 lb BW); Treatment 2: A maximum injection volume of 10 mL will be administered, but within day, multiple injections will be made to separate muscle groups to deliver the total required drug volume (5 mL/100 lb BW); and Treatment 3: A maximum injection volume of 20 mL will be administered to sows, but within day, using multiple injections will be made to separate muscle groups to deliver the total required drug volume (5 mL/100 lb BW). Sets of 9 hogs each will be slaughtered at 5, 10, 15, 20, 25, 32, and 40 days after the last drug administration. The study will be replicated twice for a total of 126 treated sows. Kidney and will be analyzed using qualitative (microbial inhibition) and quantitative (LC-MSMS) methods approved by the FSIS. Residue depletion data will be plotted with time and withdrawal periods estimated using established methods.