Feeding Study On Roughage Forages Of Caragana, Salsola And Poplar Leaves

Three roughage forages of Caragana, Solsola and poplar leaves were used to study their feeding values for goat raising in none-grazing pen-feeding period. Feeding values (in terms of nutrient contents, animal intake and dynamic digestibility in rumen) of the three forages were evaluated before and after microbial treatments. Influences of feeds with different proportions of the three forages in maize straw on rumen internal pH, NH3-N concentration, VFA concentration, distribution of feed granules and apparent digestibility, Nitrogen metabolic balance of the mixed feeds were studied. The results are as follows.â‘ Poplar leaves has the highest nutritional value among the three forage, followed by Caragana and Salsola. Dry material intake of the three forages are 59.4, 62.5, 80.1g/kgw0.75, respectively. The three forages are all in deficiency for feeding goats in terms of availabilities of dry matter, crude protein and digestible energy supply.â‘¡The PED (Potential Effective Digestibility) of poplar leaves in goat rumen is significantly higher (p<0.01) than those of Caragana and Salsola; Apart from crude protein PED, PEDs of other fiber materials and total PED of Caragana is lower than (p<0.05) that of salsola.â‘¢DOMI (Digestible Organic Matter Intake) is a suitable index for assessing roughage forage feeding value. DOMI values of roughage forages can be obtained based on the contents of NDF and ADF through the following regression equations. OMI(g/kgw^0.75)=17.67+0.698×NDF (R²=0.954,p<0.01) OM(PED)=(82.39-1.201×ADF) /100 (R²=0.919,P<0.01) DOMI(g/kgw^0.75)=OMI×OM(PED) Where, NDF and ADF are expressed as % DM in the feed. The DOMI values of poplar leaves, Salaola and Caragana were 18.99g/gk w^0.75, 14.70 g/kgw^0.75and 8.47 g/kgw^0.75, respectively.â‘£Considering the availabilities of digestible dry matter and deposited nitrogen in the animal rumens, the suitable proportion of Caragana, Salsola and poplar leaves in the mixture with maize straws are 42～43%, 42～51% and 26～42% , respectively.⑤Digestibility, decomposition rate and utilization rate of roughage forages can be improved by microbial treatments. However, microbial treatments had negative effects on energy supply ability of the roughage forages due to the loss of fiber materials during the treatment.