Figure 1.
Figure 1.

Sample pen layout. Sows in Stable and hydrocortisone acetate (HCA) treatments were penned by treatment and remained together through the 21 d experimental period. Each Mixed pen had 2 companion sows (Companion, indicated by the darker color) that did not relocate and 1 sow in the mixed treatment (Mixed) that moved to a new Mixed pen on experimental d 7 and 14. See online version for figure in color.

 


Figure 2.
Figure 2.

Sow BW gain (least square means ± SE) during the experimental period. Sows in the hydrocortisone acetate (HCA) received 70 mg HCA twice daily; Stable sows were controls; Mixed sows were moved to a new pen weekly; and Companion sows received a new pen mate weekly. High rank sows were dominant to both pen mates; middle ranked sows were dominant to 1 pen mate; and low ranked sows were subordinate to both pen mates. The analysis used 27 HCA, 27 Stable, 18 Mixed, and 35 Companion sows and 41 high, 41 middle, and 25 low ranked sows. Sow BW gain differed (P < 0.05) among social ranks (a,b) within a single treatment and among treatments (x,y) within a single social rank that do not share a letter. See online version for figure in color.

 


Figure 3.
Figure 3.

Head and body area lesions (least square means ± SE) by sow treatment (a, c respectively) and social rank (b, d respectively). Lesions were scored from 0 (least) to 5 (worst; Table 2). Experimental day -1 results were used as a covariate in the analyses. Sows in the hydrocortisone acetate (HCA) received 70 mg HCA twice daily; Stable sows were controls; Mixed sows were moved to a new pen weekly; and Companion sows received a new pen mate weekly. High rank sows were dominant to both pen mates; middle ranked sows were dominant to 1 pen mate; and low ranked sows were subordinate to both pen mates. The analyses used 27 HCA, 27 Stable, 18 Mixed, and 35 Companion sows and 41 high, 41 middle, and 25 low ranked sows. (d) Social ranks that do not share a letter had different (P < 0.05) body lesion scores on the days indicated. See online version for figure in color.

 


Figure 4.
Figure 4.

Plasma cortisol and progesterone (P4) concentrations (least square means ± SE) by sow treatment (a and c respectively) and social rank (b and d respectively). Experimental day -1 results were used as a covariate in the analyses. Sows in the hydrocortisone acetate (HCA) received 70 mg HCA twice daily; Stable sows were controls; Mixed sows were moved to a new pen weekly; and Companion sows received a new pen mate weekly. High rank sows were dominant to both pen mates; middle ranked sows were dominant to 1 pen mate; and low ranked sows were subordinate to both pen mates. The analyses used 23 HCA, 25 Stable, and 16 Mixed sows and 25 high, 23 middle, and 16 low ranked sows. (a) Treatments that do not share a letter had different cortisol concentrations (P < 0.05) on the day indicated. See online version for figure in color.

 


Figure 5.
Figure 5.

Numbers of total, liveborn, and weaned male and female pigs (least square means ± SE) by sow treatment (a,c, and e respectively) and social rank (b, d, and e respectively). Sows in the hydrocortisone acetate (HCA) received 70 mg HCA twice daily; Stable sows were controls; Mixed sows were moved to a new pen weekly; and Companion sows received a new pen mate weekly. High rank sows were dominant to both pen mates; middle ranked sows were dominant to 1 pen mate; and low ranked sows were subordinate to both pen mates. The analyses used 25 HCA, 26 Stable, 15 Mixed, and 35 Companion sows and 40 high, 40 middle, and 21 low ranked sows. See online version for figure in color.

 


Figure 6.
Figure 6.

Percentage of preweaning mortality (least square means = ± SE) of male and female piglets by sow treatment (a) and social rank (b). Sows in the hydrocortisone acetate (HCA) received 70 mg HCA twice daily; Stable sows were controls; Mixed sows were moved to a new pen weekly; and Companion sows received a new pen mate weekly. High rank sows were dominant to both pen mates; middle ranked sows were dominant to 1 pen mate; and low ranked sows were subordinate to both pen mates. The analyses used 23 HCA, 26 Stable, 15 Mixed, and 35 Companion sows and 39 high, 40 middle, and 20 low ranked sows. See online version for figure in color.