THE EFFECT OF GROUP SIZE AND HOUSING DENSITY UPON BOAR PERFORMANCE

Abstract

The effects of housing density and group size were examined for 1094 performance-tested Lacombe boars fed ad libitum, and housed in confinement on solid concrete floors in 1.2-m × 2.4-m (one or two boars per pen) or in 2.4-m × 2.4-m (three to six boars per pen) pens. There was no evidence to suggest that housing density (2.88 m2 to 0.96 m2 per boar) had any effect upon average backfat, average daily gain or feed conversion ratio. The number of boars per pen (two versus four) with constant housing density (1.44 m2 per boar) did not appear to influence the production traits. Single- and group-penned boars had no significant difference in their performance. Within the management practices typical of swine performance evaluation stations (i.e. small group size, low housing density, and feed rations for optimum growth) there was no supportive evidence that penning systems affected the performance traits. Thus, boar performance data from test stations need not be biased by group size nor housing density, and the generalities drawn from single- and, or, group-penned performance trials do not appear to be compromised. Key words: Swine, management, performance, housing density