Effect of Fennel by- Product on Performance of Growing Lambs and Gas Production Parameters of Their Diets

This research was conducted to investigate the effects of fennel by product (FBP) on productive performance of growing lamb and in vitro gas production parameters, using 20 Afshari×Chal male lambs (BW = 49 ± 0.24 kg) were used in a randomized complete block design. Experimental treatments consisted of diets including of 0, 3, 6 and 9% of FBP (dry matter basis). Dietary treatments had no effect on dry matter intake (DMI) (P>0.05). Daily weight gain was higher in lambs fed control and 6% FBP diets (P<0.05). Feed conversion ratio was higher in lambs with diet of 9% FBP compared to the others (P<0.05). Potential of gas production, fermentation rate, nutrient digestibility and partitioning factor were not affected by the experimental diets (P>0.05). The highest gas volume and microbial biomass were observed in the diet containing 6% of FBP and control diet after 24 h of incubation, respectively (P<0.05). According to the results of this experiment, addition of 6% of FBP to the diet improved feed conversion ratio and daily body weight gain of growing lambs although had no difference with control treatment.