Abstract
This study was conducted to investigate the effects of different feeding regimen on the growth and nutrients excretion in finishing pigs. A total of 80 pigs (59.91 kg BW) and 6 pigs (85 kg BW) were employed in a growth trial and metabolic trial, respectively. Treatments were grower-grower (GG), grower-early finisher(GE), early finisher-early finisher (EE), and early finisher-late finisher (EL) diet feeding regimens for feeding trial and G, E, L diets for metabolic trial. Through whole experimental period, no significant difference was found in any of the criteria measured. Pigs fed on a GG regimen gained slightly faster than pigs fed on other feeding regimens, with no significant difference. Although there was a trend that pigs fed on a GG or GE regimen showed improved feed/gain over pigs fed on a EE or EL regimen, the difference also was not significant. In the metabolic trial, dry matter and phosphorus digestibility was not affected by diets, however, phosphorus digestibility tended to be decreased as nutrients contents was decreasing in the diets. Crude protein digestibility was significantly influenced by the nutrients contents in th diets. The data suggested that 11.7% crude protein seemed to be low for the 85 kg pigs. Though nutrients excretion was not significantly influenced by dietary treatment except phosphorus, there was a trend that pigs fed diets with low nutrient content excreted less amount of nitrogen and phosphorus than pigs fed diets with high nutrients content. There was a trend that GG or GE feeding regimen gad a favorable effect on carcass grade when only 10 lighter pigs of each treatment were subjected to statistical analysis. However, with 10 heavier pigs, EE and EL feeding regimen showed better carcass grade, though the difference was not significant. In summary, it seemed that producers generally oversupply the expensive nutrients for the finishing pigs. High nutrient diets do not always guarantee high growth rate of pigs. It rather seems that to meet nutrient requirements for the each growth phase is more important in economical pork production.