Figure 4

Median number of (a) attacks initiated and (b) attacks received by resident sows ( n  = 26) and intruder sows ( n  = 11), recorded during 2 h for four consecutive days. Resident sows were moved first to the multi-suckling pen and intruder sows were moved on the following day or three days later. The range of number of attacks within groups of sows is reported above each bar. The two groups differed significantly in terms of both parameters (a: P < 0.001; b: P < 0.01).