EFFECT OF INCREASING DIETARY FAT, CALCIUM AND PHOSPHORUS LEVELS ON PERFORMANCE AND MINERAL METABOLISM OF WEANER PIGS

The influence of supplementing pig diets with 0, 5 or 10% fat, increasing dietary calcium and available phosphorus levels from 0.8 to 1.2% and from 0.53 to 0.8%, respectively, was investigated with 3-wk-old weaner pigs for a period of 6 wk. Average daily gain (P < 0.05) and feed intake (P < 0.01) were reduced with dietary fat supplementation. However, 10% supplemental fat in the diet caused an improvement (P < 0.05) in feed:gain ratio. Dietary calcium and phosphorus levels had no significant effect on daily weight gain, feed intake or feed:gain ratio. There was no significant effect of dietary fat or calcium and phosphorus treatment on digestibility of calcium, phosphorus or magnesium. There was also no significant difference in the pH of stomach and duodenal contents due to the dietary treatments. The rectal contents of pigs fed supplemental fat was found to be more acidic than those from the control group (P < 0.05). There was no significant effect of dietary fat, calcium and phosphorus treatments on bone or serum calcium, phosphorus or magnesium content. It is concluded that weaner pigs will tolerate high levels of fat without any detrimental effect on mineral digestibility and subsequent bone mineralization. Key words: Weaner pigs, fat, calcium, performance, bone and serum minerals