Effects of cereal disintegration method, feeding method and straw as bedding on stomach characteristics including ulcers and performance in growing pigs

This report investigates the effects of disintegration method (grinding or rolling of the cereal part), feeding method (feeding twice a day or nd libi tum) and straw as bedding (with or without) on empty stomach weight, volume , content, and the prevalence of gastric lesions in the pars oesophagea as well as on the performance in growing pigs. Four hundred growing pigs were included in the experiment. The grinding of the cereal was performed on a h ammer-mill, mounted with a 3-mm screen or rolled on a roller mill. Performa nce was only slightly influenced by the disintegration method and the use o f straw as bedding material, Ad libitum fed pigs, however, had a 5.5% highe r (P < 0.001) daily weight gain and a 0.6 percentage unit lower (P < 0.01) lean meat percentage compared to pigs fed twice daily. Feed with rolled cer eals increased (P < 0.001) the empty stomach weight by 13%, but only in pig s not receiving straw bedding. Ad libitum feeding reduced (P < 0.001) the e mpty stomach weight and volume by 15% and 37%, respectively. Feed with roll ed cereals increased (P < 0.001) the dry matter content of the stomach by 2 3%. The general level of gastric lesions in the pars oesophagea was low in this experiment, which most likely was due to the high content of barley in the feed mixture. The pigs receiving straw bedding, but also the pigs rece iving rolled cereals but no straw bedding, had nearly no gastric lesions (a verage score = 0.1), contrary to the pigs receiving ground feed but no stra w bedding (average score = 1.0). This interaction in gastric lesions betwee n disintegration method and straw as bedding material indicates that feedin g rolled cereals has similar preventive effects on gastric lesions as straw eaten.