Date Full Report Received10/23/2005
Date Abstract Report Received12/20/2006
Funded ByNational Pork Board
Effects of allometric space allowance and weight group composition on grower-finisher pigs.
Can. J. Anim. Sci. (in press).
There was significant difference in ADG among pigs in various space allowance treatment groups, with lower ADG at SA0.64 compared to that at SA0.81 and SA0.88. Barring the initial period of growth lag, a difference in ADG between higher and lower ‘k’ values experienced was also evident. Pigs in the lowest space allowance treatment had to spend the longest period of time below a 0.037k with respect to ADG in the trial whereas pigs in the highest space allowance treatment had to spend only a few days under that space allowance. Though the performance and welfare of pigs in SA0.81 and SA0.88 were comparable, pigs in SA0.081 were compromised in space earlier than those in SA0.88 with respect to ADG suggesting that SA0.88 would be the ideal space allowance to be provided for a market weight of 116 kg. Comparing pen efficiency among all the space allowance treatments indicated that increasing space allowance may not necessarily take away economic benefit and that it rather minimizes variation in market weight. In addition, the results also suggested welfare benefits in terms of postural behavior, lower injuries and aggression associated with higher space allowance. Allotting grow-finishers according to uniformity or variation in body weight may not provide any differential benefit in ADG or overall welfare. Although a beneficial effect was observed in terms of ADG, injury scores, aggression and lying behavior by increasing space allowance, the difference in results by an increase in space allowance from 0.64 m2/pig to 0.74 m2/pig was not significant. Similarly reducing space allowance from 0.81 to 0.74 m2/pig also did not cause further disadvantages in terms of ADG, lying behavior, injuries and aggression. It may be concluded that in fully slatted floor, space allotted considering the final market weight of barrows, corresponding to ‘k’ values of 0.037 (0.88 m2/pig) and 0.034 (0.81 m2/pig) appear to be acceptable when compared to a ‘k’ value of 0.27 in production and welfare terms. A ‘k’ value of 0.031 (0.74 m2/pig) was intermediate to higher (0.037 and 0.34) and lower (0.027) ‘k’ values.