Effects of mixing on the growth performance of finishing pigs and factors affecting the response to mixing

Five studies were conducted to evaluate the effects of mixing finishing pigs on growth performance and morbidity and mortality. Study 1 evaluated the effect of gender and of time of mixing (at either wk 9, 11, 13, 15, or 17 post-weaning) from 33.4 to 130.0 kg BW. The results of this study suggested that pigs can be mixed as late as week 17 post-weaning without affecting overall growth performance, carcass characteristics, or morbidity and mortality levels. Study 2 evaluated the effect of gender and of frequency of mixing during the marketing phase of the finishing period on the growth rate, carcass characteristics, and morbidity and mortality levels. This study showed no effect of gender or frequency of mixing (i.e., Not-mixed vs. Mixed Once vs. Mixed Twice) on morbidity and mortality levels. However, overall ADG was lower for pigs mixed twice than for those not mixed or mixed once. Studies 3 and 4 evaluated the effect of gender and BW (i.e., Light vs. Medium vs. Heavy BW) at mixing at the start of the finishing phase on growth performance and morbidity and mortality. In both studies, mixing had no effect on the growth performance of Light pigs. Mixing reduced the growth performance of Medium pigs on Study 3 but not in Study 4. Moreover, Mixing reduced the growth performance of Heavy pigs in both studies. The results of Studies 3 and 4 suggested that Mixing can have a short-term effect on the growth performance pigs, and that this effect may be influenced by other factors such as BW of pigs, but that no major long-term effect of mixing should be expected for growth performance and morbidity and mortality levels. Study 5 evaluated the effect of mixing pigs twice during the finishing phase on growth performance, and behavior (feeding and activity patterns, and aggression). The results of this study suggest that mixing pigs in the finishing period can increase the level of aggression for a short period of time, with no impact on overall growth performance or feeding patterns.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Animal Sciences

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2014

Author dc:creator

• Ochoa Zaragoza, Luis Enrique

Contributors dc:contributor

• Ellis, Michael
• McKeith, Floyd K.
• Shipley, Clifford
• Ibargüengoytia, José Antonio Cuarón
• Peterson, Beau

• Pigs
• Mixing
• Growth Performance

Statement dc:rights

• Copyright 2013 Luis Enrique Ochoa Zaragoza

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/46731

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/46731