Antibiotic resistance genes in the faeces of dairy cows following short-term therapeutic and prophylactic antibiotic administration

The objective of the research was to quantify three antibiotic resistance genes (tetQ, cfxA and mefA) in the faeces of dairy cows following therapeutic and prophylactic antibiotic treatments. Manure collected from dairy cows treated with either no antibiotic, pirlimycin hydrochloride (PIRL), ceftiofur crystalline free acid (CCFA) or cephapirin benzathine (CEPH) were submitted to quantitative PCR analysis. No treatment effects on the abundance of the tetQ and cfxA were observed. There was a trend for the abundance of the mefA to be increased in cows treated with PIRL (P = 0.07). Overall, the results showed no difference of measured three ARGs from cows receiving different antibiotics. Considering the limited scope of our investigation, further investigation is needed to provide more information on ARGs excretion from cows that received therapeutic and prophylactic antibiotic treatment.