Table 2.

Matched sets of pigs engaged in tail biting and controls.

Set	Pig ID	Sex	Age (days)	Farm	Category	Pen #	Tail damage
1	TB1	Female	104	Experimental	Biter (victim)	105	Mild
1	TB2	Female	104	Experimental	Biter	105
1	TB3	Female	104	Experimental	victim	105	Moderate
1	TB4	Female	103	Experimental	Control	106
2	TB5	Male	164	Commercial	Biter	403
2	TB6	Male	164	Commercial	Control	443
2	TB7	Male	164	Commercial	Victim	403	Moderate
3	TB8	Male	95	Commercial	Biter	222
3	TB9	Male	95	Commercial	Control	221
3	TB10	Male	95	Commercial	victim	222	Moderate
4	TB11	Female	119	Experimental	Biter	105
4	TB12	Male	119	Experimental	Victim	105	Severe
4	TB13	Female	119	Experimental	Control	106
4	TB14	Male	119	Experimental	Control	106
5	TB15	Male	109	Experimental	Victim	706	Moderate
5	TB16	Male	109	Experimental	Control	701
5	TB17	Male	109	Experimental	Biter	706
6	TB19	Male	70	Experimental	Biter (victim)	312	Moderate
6	TB20	Male	70	Experimental	Victim	312	Severe
6	TB26	Male	70	Experimental	Control	311
7	TB18	Male	70	Experimental	Victim	312	Severe
7	TB23	Male	70	Experimental	Biter	312
7	TB28	Male	70	Experimental	Control	310
8	TB21	Male	70	Experimental	Biter (victim)	312	Severe
8	TB22	Male	70	Experimental	Victim	312	Severe
8	TB27	Male	70	Experimental	Control	311
9	TB24	Male	70	Experimental	Bitera	313
9	TB25	Male	69	Experimental	Victim	313	Severe
9	TB29	Male	70	Experimental	Control	310

^aThe biter in set 9 could not be identified with certainty according to our definition of a tail biter pig. Three individuals identified as a biter had wounds on their tail and so were also classified as victims.