Abstract:
In order to investigate the effects of millet straws on growth performance, slaughter performance and economic benefit of mutton sheep, a single factor design was adopted in this experiment. Seventy-five healthy six-months-old healthy crossbred rams with average initial weight were randomly divided into control group, trial group 1, trial group 2, trial group 3 and trial group 4, with five replicates in each group and three sheep in each replicate. The feeding trial included 15 d of pre-test period and 45 d of formal period. Animals in the control group were fed a basal diet containing a roughage corn stalk-alfalfa mixture. Animals in experimental groups 1, 2, 3 and 4 were fed diets containing 5%, 10%, 15% and 20% millet straw instead of roughage, respectively. At the end of the experiment, the growth performance index, slaughtering index and total revenue of experimental sheep were determined, and then the fattening effect of adding different levels of grain grass to diet was analyzed. The results showed that the daily gain, net meat gain and total revenue of fattening sheep in experimental groups were higher than those of fattening sheep in control group, but there was no significant difference in slaughter rate among all groups(P>0.05). The average daily gain in trial group 2 was significantly higher than control group(P<0.05), the net meat gain and net meat rate in trial groups 1, 2 and 3 were significantly higher than that in control group(P<0.05), and the total revenue and earnings in trial group 2 was the highest. The results indicated that add millet straw in the diet could improve average daily gain, net meat gain and economic benefit of mutton sheep. The suitable addition amount millet straw was 10%.