The Effect of corn and sorghum silages particle size on feed intake, digestibility and rumen parameters in Kermani sheep

This research was conducted to investigate the effects of corn and sorghum silages particle size on feed intake, digestibility, rumen parameters and feed intake behavior in Kermani sheep. Around 1000 kg of fresh corn and sorghum forages were chopped into two coarse and fine particle sizes and ensiled for 45 days. Four male Kermani sheep, 34.0±0.8 kg average BW, were used in this experiment which was conducted in a completely randomized design, with a 2 × 2 factorial experiment. There were four experimental periods and each of which lasted 21d, with 14d adaptation, 7d of sample collection. The ratio of forage to concentrate was 60: 40. Experimental diets were: 1) coarse corn silage diet, 2) fine corn silage diet, 3) coarse sorghum silage diet and 4) fine sorghum silage diet. The NDF content was higher in the sorghum silages than corn silages (p<0.05). In diets containing fine silage, ruminal pH tended to decrease after two hours of intake. Population of Holotrich and Cellulolytic protozoa increased when coarse silages were fed to animals (P<0.05). The maximum microbial protein synthesis in the rumen was achieved in diets containing fine silage(P<0.05). Duration of feed intake, rumination and chewing activity were higher in coarse silage diets (P<0.05). The types of silage did not have significant effect on animals’ performance and dietary feed intake behavior. In conclusion, corn silage can be replaced by sorghum silage, without any negative effect on feed intake, digestibility, and rumen parameters in sheep.