Comparison of antimicrobial resistant Escherichia coli isolated from Irish commercial pig farms with and without zinc oxide and antimicrobial usage

Table 1 Comparison of antimicrobial resistance patterns of Escherichia coli isolated on supplemented TBX agar plates

	Apramycin-supplemented TBX			Ciprofloxacin-supplemented TBX			Cefotaxime-supplemented TBX
Antimicrobial agent	AB-ZnO free [n = 82] (%)	AB-ZnO [n = 127] (%)	p-value	AB-ZnO free [n = 46] (%)	AB-ZnO [n = 43] (%)	p-value	AB-ZnO free [n = 17] (%)	AB-ZnO [n = 36] (%)	p-value
Apramycin	100.00	100.00	–	26.09	23.26	0.757	35.29	97.22	< 0.001 (*)
Trimethoprim	63.41	86.61	< 0.001 (*)	78.26	90.70	0.107	64.71	66.67	0.888
Nalidixic Acid	18.29	11.02	0.138	76.09	83.72	0.370	41.18	19.44	0.094
Tetracycline	63.51	90.55	< 0.001 (*)	86.96	90.70	0.577	47.06	100.00	< 0.001 (*)
Meropenem	0.00	0.00	–	0.00	2.33	1.000	0.00	0.00	–
Cefotaxime	4.88	3.15	0.525	4.35	6.98	0.590	100.00	100.00	–
Ciprofloxacin	28.05	16.54	0.046 (*)	100.00	100.00	–	64.71	25.00	0.005 (*)
Streptomycin	69.51	92.13	< 0.001 (*)	84.78	69.77	0.090	35.29	91.67	< 0.001 (*)
Chloramphenicol	19.51	48.03	< 0.001 (*)	32.61	72.09	< 0.001 (*)	0.00	58.33	< 0.001 (*)
Multi-drug resistant	68.29	94.49	< 0.001 (*)	89.13	93.02	0.521	64.71	100.00	< 0.001 (*)

Results are divided based on the supplemented antimicrobial that was used and comparison between AB-ZnO using and AB-ZnO free farms was conducted using the Chi-square test. Statistical significance is indicated using an asterisk next to the p-value displayed. N number of resistant E. coli; multi-drug resistance was defined as resistant to at least three different antimicrobial classes

ISSN: 1757-4749