The effect of two different protein and roughage feed sources on feedlot performance, digestibility of nutrient and fuminal fermantation in lambs

The aim of this study was to examine the differentiation in crude nutrient matter composition of barley- vetch hay according to baling time (at three hour periods between 6.00 -21. °° ) and the effects of two different protein sources (soybean meal and cottonseed meal) and roughage feed sources (straw and barley-vetch yield) on feedlot performance, digestibility of crude nutrient matter and ruminal fermentation in lambs. 28 Akkaraman lambs at average weight of 20 kg and age of 4 months were used in the study. The experiment was conducted according to 2x2 factorial arrangement. Experimental diets were consist of equal energy and crude nutrient matter levels as suggested by NRC standards. The study groups were determined according to the protein and roughage sources in the diets; I. group included soybean meal, n. group cottonseed meal, HI. group straw and IV. group included barley vetch hay in diet composition. The composition of diets was changed between 0-56 * days as the need of animals differed according to NRC-standards (I. Period) and between 56-1 12 * days as appropriate to the needs (II. period). Baling time effected crude protein and fiber levels, significantly (P<0.05). Thus, the highest crude protein level and the lowest crude fiber level were obtained between 6.00 -21. °° hours. Crude fiber level increased at following hours, while crude protein level decreased. Total dry matter intake was determined as 1762.58, 1820.23, 1655.49 and 1937.30 g DM/day in the groups, respectively. The highest daily feed intake was detected in barley- vetch hay group. Average daily live-weight gain in the groups was determined as 259.57, 233.74, 240.75 and 252.55 g/day, respectively. The effect of soybean meal and barley-vetch hay on daily live-weight gain was found to be statistically significant (P<0.05) in this experiment. However, this effect was not consistent in terms of feed conversion. The digestibility of dry matter, crude protein, crude fiber and nitrogen-free extract was increased by the addition of soybean meal to the diets (P<0.05). The digestibility of organic matter, ADF and NDF was increased by the addition of soybean meal and barley-vetch hay to the diets particularly at II. period of the experiment (P<0.05). The pH value of ruminal fluid did not different significantly between the groups. The ammonia value in ruminal fluid was increased significantly by the addition of soybean meal and barley- vetch hay to the diets at I. Period, whereas only soybean meal increased its value at II. period. Total volatile fatty acid concentration of ruminal fluid did not differ significantly by the addition of soybean meal55 and barley-vetch hay to the first diets. In contrast, total volatile fatty acid concentration was determined to increase significantly in samples taken 4 hours after feeding, by the addition of the above feeds at II. period (P<0.01).