Abstract
The objective of the study is to know the influence of level of concentrate on performance of free-ranging fattening pigs, on the deteriorated pasture and also the effect of grazing on cleaning of vegetation in the pasture. Experimental paddocks mainly composed of Pennisetum alopecuroides and Pteridaceae aquilinum var. latiusculum. Ten fattening pigs (LDW) were allocated to one of three treatments and reared outdoor during fattening period. In the control treatment (C), pigs were offered concentrate at 120% level of Japanese Feeding Standards. In the middle level treatment (M), pigs were offered concentrate at 80% level of C treatment. In the low level treatment (L), pigs were offered at 60% level of C treatment. There was no significant difference in daily weight gain (about 600g/day) between C and M (p>0.05). Concentrate requirement was the lowest for pigs in the M treatment. There was no significant difference in carcass dressing percentage, backfat thickness and carcass grade (p>0.05). In all the treatments, vegetation coverage including Pennisetum alopecuroides and Pteridaceae aquilinum var. latiusculum were almost eliminated by grazing pigs at the 74^<th> day after beginning of grazing.
