289
Evaluation of the growth performance, feeding and activity patterns, and aggressive behavior of barrows mixed twice during the finishing period

Wednesday, March 19, 2014
Grand Ballroom - Posters (Community Choice Credit Union Convention Center)
Luis E. Ochoa , The University of Illinois, Urbana, IL
Leah M Gesing , University of Illinois, Champaign-Urbana, IL
Beau Peterson , The Maschhoffs, Carlyle, IL
Michael Ellis , University of Illinois, Urbana, IL
Abstract Text:

The effect of mixing pigs twice during finishing on growth performance, feeding and activity patterns, and aggressive behavior was investigated in a study involving 48 barrows. The study was carried out over a 10-wk period (65.3 ± 4.4 kg to 136.5 ± 7.6 kg BW) as a generalized randomized block design (blocking factor day of start on test) with 2 treatments: 1) Control (Not-mixed); 2) Mixed (mixed at start and at wk 5 of the study). The study involved 4 pens of 12 pigs; pens were equipped with an electronic feed station that recorded the time and duration of visits and the weight of feed consumed/visit for each animal in the group. For the first mixing event, the 12 pigs in the 2 pens on the Mixed treatment were divided into 2 subgroups of 6 pigs with the same mean and variation in BW and one subgroup from each pen was exchanged with a subgroup from the other pen. For the second mixing event, the subgroups of 6 that were mixed had not previously been mixed together. Activity (numbers lying, standing, eating, and drinking) and aggressive interactions (number of bites and fights of greater than 3 seconds duration) were recorded on the d before and d of mixing, and d 1, 2, and 3 post-mixing. During the recording period, activity was recorded every 10 minutes and aggressive interactions were recorded continuously. There was no effect (P > 0.05) of mixing on growth performance or feeding patterns for the periods immediately after mixing or for the overall study period. Mixing increased (P ≤ 0.05) the percent of pigs standing (6.9 vs. 9.7% for Control and Mixed, respectively) and reduced (P ≤ 0.05) the percent of pigs lying (85 vs. 82%, respectively) for the 3 d following the first, but not the second (P > 0.05), mixing event. Mixing increased (P ≤ 0.05) the number of fights/pig (0.0 vs. 1.8, for Control and Mixed, respectively) on the d of mixing of the first mixing event, but not on the following days or for any day after the second mixing event (P > 0.05). These results suggest that mixing pigs in the finishing period can increase the level of aggression for a short period of time, with no impact on growth performance or feeding patterns.

Keywords: behavior,  Mixing, Pigs.