The effect of fibre type in a diet containing fine maize to improve the performance and health of pigs during the final finisher phase

Abstract

The importance of maize grind size in commercial pig rations are oversighted, a substantial amount of nutrients is annually lost due to undigested maize. Pig production could benefit from an increased nutrient availability, without increasing the feed costs. The challenges producers are faced with when feeding a finer feed are firstly; fine feed tend to bridge in the feeding system and secondly; gastric ulcers often develop. In this study, the effects of using a finer maize (741 µm) particle in finisher pig rations in combination with sunflower meal were investigated to alleviate the risk of gastric ulceration. Finisher pigs of Topigs Norsvin genetics were fed in a commercial set-up, with industry standard rations, after which they were slaughtered at a commercial abattoir. A total of 288 pigs were used for the study, divided into six treatment groups with six replicates each. The trial was designed with six treatments in a 2 x 3 factorial arrangement, examining the main effects of fibre source (wheat bran and sunflower meal) and maize grind size (720 μm, 741 μm, and 774 μm). Statistical analysis was conducted by ANOVA using SAS software, while blocking was applied to minimise facility effect. The pigs were fed these treatment rations during the finisher phase, from 19 weeks-of-age until slaughter at 22 weeks-of-age, when pigs are most likely to develop gastric ulcers. Average daily feed intake (ADFI), feed conversion ratio (FCR), average daily gain (ADG), gastric ulceration scores and carcass characteristics were evaluated during this study. Total tract nutrient digestibility was evaluated using chromium dioxide as an indigestible marker. There was no significant difference (P > 0.05) in the performance parameters and carcass characteristics of the pigs during this study. Pigs administered sunflower meal as fibre had a significant difference (P < 0.05) in digestion of amino acids, crude fibre and starch during the trial. There was no increase in gastric ulcerations all through the study. It was concluded that a diet with medium maize particle sizes of 741 µm on average and with the inclusion of fibre from sunflower meal, enhanced digestibility and did not negatively impact the gastrointestinal tract (GIT) of finisher pigs during this study.