As the impact of upcoming climate change scenarios on livestock feeding security (quality, availability, and price), applying alternative feedstuffs is a must. Fattening calves considered as a most process related to traditional feeding system. In the present study we purposed new feedstuffs for fattened calves consisting citrus pulp silage, wheat germ, barley sprout and molasses. Within the above feedstuffs we using mechanical, chemical, and biological treatments. Moreover, the present study evaluates the production performance of 14 male cross Friesian calves (7 per each group) for adding 10ml/calve/day probiotic ZAD in treated group. Weight data where used to calculate Average Daily Gains ADG, nutrients digestibility, boneless meat percent, and feed conversion rate. From our results applying probiotics (ZAD) increased significantly (P<0.05) ADG in the hall fattened period by 1.011±0.107 kg/calve/day and 0.886±0.107kg/calve/day, also, increased the percent of boon less meat from 51.097±1.140 % and 44.410±1.518% in the treated control group respectively. Applying probiotic increasing significantly (P<0.05) digestibility of nutrient detergent fiber and acid detergent fiber by 42.853±7.092 and 54.010±3.774 in treated group compared with 25.180±7.902 and 37.679±3.774 respectively.
Based on the results of the present study concluded that the effect of probiotic treatment on feed conversion rate of intake nutrients showing significant different (P<0.05) in Total Intake of Digestible Nutrients TDNI was higher in control group (4.579) compared with treated group (3.305). However, Dry Matter Intake DMI and Crud Protein Intake CPI tended to be higher in control group compared with treated group.
In conclusion applying probiotics in agriculture byproduct silage in presence of sprout, molasses and wheat germ results in improving in nutrients digestibility, growth performance, and feed conversion rate of fattened calves. Based on our results we recommend such feeding system as a solution in calves' meat production to facing the upcoming climate change scenarios (i.e. direct and indirect effects on livestock sector.