| Three experiments at present study were conducted to investigate the utilization/digestion and optimum concentration of fibers, crude protein (CP) and energy in growth emu dietary.Experiment 1. Comparative study on utilization/digestion of fibers, crude protein, ether extract and energy between in emus and in turkeys or cocks.5-month and 7-month old emus or turkeys, and adult cocks were used to investigate the differences of utilization/digestion/metabolism of fibers, CP, ether extract (EE) or energy between age or poultries The results showed that, 1) Intakes, excreta and utilizations/digestions in emu were higher (P<0.05) than in turkeys or cocks. 2) Digestible fibrous component (crude fiber (CF); acid detergent fiber (ADF) and neutral detergent fiber (NDF)) in emus are greater than in cock or turkey, and were significantly (P<0.05) enhanced from 5-month old to 7-month old, 3) Utilizable efficiency of EE and CP in emus were slightly lower than in cocks or turkeys, and no significant differences between 5-month-old emus and 7-month-old ones. 4) Utilization of DM and metabolism of energy in 7-month-old emus were significantly higher (P<0.05) than in turkeys or cocks, but this significant difference is not found between 5-month old emus and other poultry species. It is concluded that enhancement of DM utilizable or metabolic efficiency are attributed to the improvement of utilizable fibers.Experiment 2. Effects of dietary fiber levels on dietary fibers and protein utilizable efficiency of emus.15-month old emus were conducted to examine the effects of dietary fiber levels on fibers and CP utilization, to discover condign content of the fiber in emu diets. The results showed that digestible efficiency of ADF, NDF or CF are not influenced by the increasing dietary fiber levels when alfalfa meal contents in diets were 10% or less, and were decreased by further increasing of fiber contents in diets. Dietary CP utilizable efficiency was the highest when alfalfa meal content was 5%, and was significantly (P<0.05) decreased by the increasing dietary fiber levels when alfalfa meal contents exceeded 5%. When dietary CP utilizable efficiency was the highest, dietary fiber contents were ADF 7.4%, DNF 16.4% and CF 5.5%, which is condign dietary fiber levels in emu dietary.Experiment 3. Effects of dietary energy or crude protein levels on utilization of dietary energy and crude protein in emu.Twenty-four 7-month old emus were conducted to investigate the effects of dietary energy (trial 1) or CP (trial 2) levels on CP utilizable efficiency and apparent metabolic ratio, individually. The results indicated that dietary CP, ME and CP/ME concentration are individual 20%, 11.92 MJ.kg-1, 16.78g/MJ.ME and 18%, 11.08 MJ.kg'1 and 16.25i g/MJ.ME n trial lor 2, when utilizable efficiency of CP and metabolic ratio of energy reach peak. It is suggested that condign level of CP, ME amd CP/ME in 7-month old emu dietary is 18%, 11.08 MJ.kg-1 andl6.25~16.78g/MJ.ME.In conclusion, these results at present study showed that 7-month old emu has greater ability of utilization of fibrous content and can absorb less protein compared with cock or turkey because of different digestive tract structure, metabolism mechanism or genic factors. And the condign nutrient contents (ADF 7.4%, DNF 16.4% , CF 5.5%, CP 18% and ME 11.08 MJ.kg-1) in growth emu diets had been obtained by index of CP digestibility.
|
PDF Full Text Request