The Effect of Using Different Levels Fodder Beet Silage on Performance and Carcass Characteristics of Gray Shirazi Fattening Lambs

In this study, the possibility of replacing fodder beet silage in proportions of zero, 25, 50 and 75% based on dry matter in the concentrated part of fattening ration of Grey Shirazi male lambs (forage: concentrates in the ration 60:40 percent) were evaluated. Experiment carried out in a completely randomized design with 4 treatments and 10 replications. Silage chemical composition and performance of lambs were evaluated. At the end of the period, the all lambs were slaughtered and carcass and meat characteristics were evaluated. The chemical composition of silage including dry matter, ash, crude protein, ether extract, neutral detergent fiber and acid detergent fiber Were 25, 16, 12.7, 1, 41 and 30% of DM, respectively. The average (kg) of initial weight, final weight, average daily gain and feed efficiency were not significantly different in the treatments (p>0.05). The mean of dry matter intake in the treatments (25, 50, 75 percent) that consumed fodder beet silage (1160.0, 1147.3, 1091.9 gr/d) was significantly reduced in compare to control treatment (1298.8) (p<0.05). The mean of feed conversion ratio in treatment with 50% replacement of fodder beet silage (4.8) showed a significant decrease in compare to control treatment (5.7) (p<0.05), but treatments of 25 and 75% replacement of fodder beet silage with control treatment and also with treatment of 50% fodder beet silage were not significantly different (p>0.05). Carcass and meat characteristics were not significantly affected by fodder beet silage feeding. The results of this study showed that the use of fodder beet silage in feeding fattening lambs up to 75% substitution of the concentrate part of the ration is possible without reduction in yield.