The goal of this study was to identify practical enrichments for sows in partially or fully slatted pen systems. Four treatments were applied: (1) Constant: constant provision of wood on chain; (2) Rotate: rotation of rope, straw and wood enrichments; (3) Stimulus: rotation of enrichments (as in Rotate) with an associative stimulus (bell or whistle); and (4) Control: no enrichment, with each treatment lasting 12 days. Six groups of 20 ± 2 sows were studied from weeks 6 to 14 of gestation in pens with one electronic sow feeder. Each group received all treatments in random order. Six focal animals (3 dominant and 3 subordinate) were selected per pen using a feed competition test. Digital photos were collected at 10 min intervals for 8 h (between 8 a.m. and 4 p.m.) on 4 days/treatment (d 1, 8, 10 and 12) to record interactions with enrichment. Skin lesions were assessed on days 1 and 12, and saliva cortisol samples collected in weeks 6, 10 and 14 of gestation on focal pigs. Sows spent more time in contact with enrichments in Rotate and Stimulus treatments than Constant. Enrichment treatments did not influence lesion scores. Subordinate sows spent more time standing and near enrichments than dominants. Subordinate sows also received more skin lesions and had higher salivary cortisol concentrations than dominants. These results indicate that access to enrichment is valued by sows but can result in greater aggression directed towards subordinates.

The efficacy of analgesics such as meloxicam and ketoprofen to control pain in piglets when mixed with iron dextran (ID) before injection is unknown. The purpose of this study was to compare perceived pain in castrated piglets treated 1 h before castration with either of these drugs alone, or when mixed with ID, by observing the time it takes for piglets to navigate a chute. Piglets were divided into seven treatment groups (n = 25 piglets per treatment group) including castration with analgesia (meloxicam or ketoprofen), castration with analgesic plus ID, castration without analgesic or ID, sham handled and given ID, and sham handled alone. Piglets were placed in a short chute and their time to navigate the chute was recorded at four timepoints following castration. Piglets given meloxicam or ketoprofen, with or without ID did not differ from each other in their chute navigation times. Additionally, these piglets did not differ from treatment groups that were not castrated. Piglets castrated without analgesia had significantly longer navigation times. These results indicate that meloxicam or ketoprofen, whether mixed with ID prior to injection or not, provide similar analgesic efficacy.

Continuing with previous research by our group in an ESF system, four types of enrichment treatments were assessed in gestating sows housed in Free Access Stalls: (1) Constant: constant provision of wood on chain; (2) Rotate: rotation of rope, straw and wood; (3) Stimulus: rotation of enrichments with an acoustic cue; and (4) Control: no enrichment. Treatments had a 12 day-duration. Four groups (28 ± 2 sows) were studied from weeks 6 to 14 of gestation. Groups received all treatments in random order. Three dominant and 3 subordinates per pen were selected using a feed competition test. Digital photos were collected at 10 min intervals for 8 h on days 1, 8, 10 and 12 to record interactions with enrichment. Skin lesions were assessed on days 1 and 12, and salivary cortisol was assessed in weeks 6, 10 and 14 of gestation. More enrichment use was observed in Rotate and Stimulus treatments compared to Constant, and more sows contacted enrichment when straw was provided in the Rotate and Stimulus treatments. There was no difference in the amount of enrichment use by dominants and subordinates, no cortisol concentration elevation in subordinate sows nor any difference in lesion scores. In conclusion, social status had little impact and feeding system is important to reduce stress and aggression.