Effect of cereal type, disintegration method and pelleting on stomach content, weight and ulcers and performance in growing pigs

The purpose of this study was to investigate the effects of cereal type and feed processing on the prevalence of gastric lesions in pars oesophagea, s tomach size, stomach content and firmness and performance in growing pigs. Data from 320 pigs were included in a 2 x 2 x 2 factorial experiment. The f actors investigated were cereal type (barley or wheat), disintegration meth od (grinding or tolling) and feed form (pelleted or non-pelleted). Gastric lesions were investigated at slaughter and scored on a scale from 0 (normal ) to 10 (very severe changes). The ground feed was produced on a hammer-mil l, mounted with a 3-mm screen for barley and a 4.5-mm screen for wheat. Onl y 20% of the ground feed consisted of particles bigger than 1 mm in diamete r, whereas it was approximately 50% of the rolled feed. Disintegration meth od and pelleting did not influence performance significantly and the differ ences between wheat and barley were due to the higher energy content in whe at rather than wheat per se. Wheat, ground feed and pellets reduced the emp ty stomach weight. Non-pelleted rolled feed increased both the firmness and dry matter percentage of the stomach content compared to ground feed. Roll ed barley could be pelleted without a decrease in firmness of the stomach c ontent as opposed to wheat. Pigs receiving rolled barley or wheat in non-pe lleted form had nearly no gastric lesions (average score = 0.7) as opposed to pigs receiving ground barley or wheat (average score = 2.8). Rolled barl ey could be used as pellets without causing a high level of gastric lesions (average score = 1.3), while rolled pelleted wheat caused a high level of gastric lesions (average score = 4.3). The combination of ground wheat as p ellets resulted in the highest score of gastric lesions (average score = 4. 9). A high firmness of the stomach content coincided with a low score of ga stric lesions. (C) 2000 Elsevier Science B.V. All rights reserved.