Comparative studies on the effects of feeding different types of oils at two levels on the performance and carcass characteristics of growing pigs in the tropics

Abstract

SUMMARYTwo feeding trials involving 105 pigs weighing approximately 14·5 kg were carried out to investigate the effects of palm oil, groundnut oil, locally produced lard, and beef tallow at 2·5% and 5% of the diet, on performance characteristics and carcass quality. The pigs were of the Yorkshire and Yorkshire × Landrace crosses, and of both sexes. The 23% protein basal diet had no oil added, and the other eight diets were made from the basal diet by the weight-for-weight substitution of the maize with the 2·5% or 5% levels of the four oil types. The results of the two trials were combined and considered as a 2 × 4 factorial experiment (2 levels and 4 types of oil) with the basal diet serving as the control. Only the pigs in the second trial were slaughtered and their carcasses graded at the average live weight of 57±1 kg. Correlation and regression analyses were made on some performance and carcass characteristics, on the average daily digestible energy intake. Results showed no significant treatment differences in the average daily gains, average daily feed intake, and average daily digestible energy intake, but there were highly significant treatment differences in feed consumed/kg of gain and average digestible energy (DE) consumed/kg of gain (P<0·01). None of the carcass quality parameters showed any significant treatment differences. Both the correlation and the regression coefficients for the average daily gain on DE intake were highly significant for all the oil types and levels, but the relationships were low and non-significant when the feed/gain ratio, average backfat thickness and the average percentage of lean cuts were regressed on the daily DE intake.