Genotype variation and genetic relationship among Escherichia coli from nursery pigs located in different pens in the same farm

Table 2 Shannon diversity index of each group analyzed

Group/level	N isolates	N clusters	Shannon diversity index
Pen 1	180	11	2.28
Pen 2	180	12	2.27
Pen 3	180	11	2.37
Pen 4	180	10	2.34
Between pens	720	20	2.57
No antibiotic^a	288	10	2.07
Ampicillin^a	216	18	2.56
Tetracycline^a	216	12	2.38

^aNo antibiotic, ampicillin and tetracycline denote whether colonies were obtained from plates without or with the mentioned antibiotics

ISSN: 1471-2180