Table 3.
Distribution within flocks of 22 different PFGE types of 92 S. aureus isolates from ewes with intramammary infection (IMI). Only flocks in which at least one ewe experienced bilateral S. aureus IMI and two ewes experienced clinical mastitis are included. The observed pairs of PFGE types from the ewes with bilateral S. aureus IMI are shown. Also shown is the expected distribution of pairs with equal and unequal PFGE type combinations when assuming random pairwise distribution of the observed isolates within each flock.
| Expected pairs (n) | |||||
| Flock | Ewes with IMI (n) | S. auerus types (n) present in flock | Bilateral PFGE type combinations | Equal | Unequal |
| F1 | 6 | K, P, Q (4), R | 6 | 15 | |
| F2 | 9 | I, J, L (7), M | LL | 21 | 24 |
| F3 | 2 | R (3) | RR | 3 | 0 |
| F4 | 3 | R (4) | RR | 6 | 0 |
| F5 | 2 | H (2), O (2) | HH, OO | 2 | 4 |
| F6 | 2 | D (2), H | DD | 1 | 2 |
| F7 | 2 | H, I, U | IU | 0 | 3 |
| F8 | 2 | H (3), X | HH, HX | 3 | 3 |
| F9 | 2 | D, H (3) | DH, HH | 3 | 3 |
| F10 | 2 | I, M, V | IV | 0 | 3 |
| F11 | 6 | H (5), I, W | HH | 10 | 11 |
| F12 | 3 | H, I (3) | II | 3 | 3 |
| F13 | 3 | H (4), I (2) | HH, HH, II | 7 | 8 |
| F14 | 3 | F, J (3) | JJ | 3 | 3 |
| F15 | 2 | H, S (2) | SS | 1 | 2 |
| F16 | 2 | D (3) | DD | 3 | 0 |
| F17 | 4 | H (2), I (2), N, G (2) | HH, II, GG | 3 | 18 |
| F18 | 2 | C (2), E | CC | 1 | 2 |
| F19 | 2 | C (2), G | CC | 1 | 2 |
| F20 | 3 | I (2), R, T | II | 1 | 5 |
| F21 | 2 | A (2), B | AA | 1 | 2 |