Effects of physical conditions of feed such as form and hardness on feeding behavior and feed intake of pigs

The purpose of this study was to investigate the effect of physical condition of feed on the palatability of pigs. This study was designed to examine the influence of feed form and hardness upon feed intake and feeding behavior. Four pigs (cross-bred) weighting 40-50 kg were used to carry out the experiment with triplication under a Latin Square Design. As the test feed, four types were prepared from the commercial feed mash, pellet of diameter 3 mm, pellet of diameter 5 mm and tablet of diameter 13 mm. To make mash, the material was ground until it was put through a 1 mm screen. Other three types of feed were prepared after the addition of 1 % silicone powder. These feed types showed different value of hardness; pellet of diameter 3 mm, 1.15 kg/square cm ; pellet of diameter 5 mm, 0.34 kg/square cm ; tablet, 2.3 kg/square cm. The pigs were housed in individual cages in the environmentally controlled room at 25 =+- 20 deg C. Feed was provided twice a day at a daily rate of approximately 4% of body weight. Water was provided ad libitum. Feed intake and feeding behavior were observed for 20 minutes at each feeding. Feed intake in tablet group and pellet of diameter 3 mm group was significantly higher than in the other groups. Feed wastage in tablet group was significantly lower than that in mash and pellet of diameter 5 mm groups. As a result of feeding behavior for 20 minutes, the number of times the pigs in mash group drunk water showed the highest values, and mash and pellet of diameter 5 mm groups took long time for water drinking. The above-mentioned results suggested that the hard feed like a tablet or pellet of diameter 3 mm was easy for pigs to take feed. Oppositely soft feed was not their favorite. Therefore, the form of feed didn't affect the palatability of pigs, as long as it showed certain hardness.