بررسي عملكرد سورگوم علوفه اي نسبت به ذرت علوفه اي سيلو شده در پرواربندي گوساله هاي نر

Comparative study of sorghum and corn silage performance on the diet of finishing calves

This experiment was conducted to compare performance of sorghum with corn forage in feedlot cattle nutrition, during 2003-2004. Sorghum and corn were planted each in three hectares and the forage was ensiled. In a completely randomized design, 32 yearling Holstein male calves with 229±1.2 Kg initial weight were fed with four finishing diets, contained 40% silage (DM basis) in which, corn silage was substituted by sorghum silage in amounts of 0.00 , 33 , 66 , and 100 percent respectively. The harvested forage was 80 and 85 tons/h for sorghum and corn respectively, but the seed used in sowing was 4 and 30 kg/h and irrigation was 8 and 11 times for sorghum and corn respectively. During the 120 days of feeding trial, average daily gain were 1038, 1069, 1010 and 1158 g for the diets 1, 2, 3 and 4 respectively which were not significantly different. The average dry matter intake was 7.50, 7.56, 7.74 and 8.06 kg/d respectively, which was not significantly difference among the diets. Feed conversion ratio was 7.23, 7.07, 7.66 and 6.59 respectively and no significant variation was observed among the treatments.