Jones, Robert M

Crump, Ronald E

Hermesch, Susanne

2011

Records from 9429 pigs raised in 353 grower groups in a commercial Australian piggery were analysed to determine whether grower-group characteristics affected daily gain and backfat of individual pigs. Individual and group effects as well as their interactions were tested for significance (P < 0.05) in a mixed model, with sire fitted as a random effect. Group characteristics affected average daily gain (ADG) more than backfat (BF). The proportion of males in a group influenced both traits significantly, as did the average number of full siblings. Groups with 10-30% of the opposite sex had the highest BF and a 21-30 g/day reduction in ADG compared with the highest-performing groups with less than 10% of males. Each additional full sibling per group increased ADG by 5.5 ± 1.60 g/day and BF by 0.12 ± 0.05 mm. Additionally, ADG increased by 9.8 ± 2.64 g/day per second of group mean flight time and by 4.5 g/day per 10% increase in the proportion of Duroc pigs per group. Group size affected ADG (linear and quadratic) and BF (linear); however, the effect on ADG was considerably larger during the warmer grower season. In commercial piggeries, it may be possible to optimise individual daily gain through the manipulation of grower-group characteristics. Advantages for growth rate arose from including a portion of a calmer line of pigs within groups, optimising the stocking density in warmer months and maximising the proportion of quieter, less fearful pigs in grower groups.

Animal Production Science, 51(3), p. 191-197

1836-5787

1836-0939

https://hdl.handle.net/1959.11/9813

CSIRO Publishing

Group characteristics influence growth rate and backfat of commercially raised grower pigs

Journal Article

Publication