Residues of Veterinary Antibiotics in Pig Feeds and Manures in Zhejiang Province

Abstract

To investigate the concentrations of oxytetracycline (OTC), tetracycline (TTC), chlortetracycline (CTC) in pig feeds and manures, 30 samples of pig manures and 30 samples of pig feeds in different growth periods of pigs were sampled in Zhejiang Province in China. The results showed that the means of the concentrations of OTC, TTC and CTC in pig feeds were 8.76, 6.62 and 23.26 mg kg-1, respectively. The concentrations of OTC, TTC and CTC in manures were 2.98, 3.00 and 4.62 mg kg-1, respectively. The concentration of CTC in pig feeds were 2~4 times higher than that of OTC and TTC. The concentrations of OTC, TTC and CTC in manures from piglets were positively correlated to those in their feeds, with the correlation coefficients of 0.64, 0.61 and 0.58, respectively. It suggested that less amount of antibiotics should be added in piglet feeds than in other pig feeds.